/* Graphing Calculator - Component Styles */
/* Design: Premium Violet with glassmorphic dark mode  */
/* UI/UX Pro Max: Modern Dark Cinema + Glassmorphism hybrid */

:root {
    --gc-tool: #8b5cf6;
    --gc-tool-dark: #7c3aed;
    --gc-gradient: linear-gradient(135deg, #8b5cf6 0%, #6366f1 50%, #7c3aed 100%);
    --gc-light: #f5f3ff;
    --gc-radius: 12px;
    --gc-radius-sm: 8px;
    --gc-radius-xs: 6px;
    --gc-shadow-card: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
    --gc-shadow-card-hover: 0 4px 12px rgba(139,92,246,0.1), 0 2px 4px rgba(0,0,0,0.06);
    --gc-shadow-elevated: 0 8px 24px rgba(139,92,246,0.12), 0 2px 8px rgba(0,0,0,0.08);
    --gc-transition: 200ms cubic-bezier(0.16, 1, 0.3, 1);
    --gc-glow: 0 0 0 1px rgba(139,92,246,0.06);
    --gc-surface: rgba(255,255,255,0.85);
}
[data-theme="dark"] {
    --gc-light: rgba(139, 92, 246, 0.12);
    --gc-input-bg: #0f0d1a;
    --gc-input-border: rgba(139,92,246,0.25);
    --gc-input-border-focus: #a78bfa;
    --gc-shadow-card: 0 1px 3px rgba(0,0,0,0.3), 0 0 0 1px rgba(255,255,255,0.04);
    --gc-shadow-card-hover: 0 4px 16px rgba(139,92,246,0.2), 0 0 0 1px rgba(139,92,246,0.15);
    --gc-shadow-elevated: 0 12px 32px rgba(0,0,0,0.4), 0 0 0 1px rgba(139,92,246,0.2);
    --gc-glow: 0 0 0 1px rgba(139,92,246,0.12);
    --gc-surface: rgba(15,13,26,0.75);
}

/* ===== Grid Override: Two-Column Layout (input + graph) ===== */
.gc-page-container.tool-page-container {
    grid-template-columns: minmax(260px, 320px) 1fr;
    gap: 1rem;
    max-width: 1400px;
    margin: 0 auto;
    padding: 1rem;
    align-items: start;
}
/* Remove any inherited padding/gap on the output column; make it the sticky element */
.gc-page-container .tool-output-column {
    gap: 0;
    padding: 0;
    margin: 0;
    position: sticky;
    top: 90px;
    height: fit-content;
}
@media (max-width: 900px) {
    .gc-page-container.tool-page-container {
        grid-template-columns: 1fr;
        display: flex;
        flex-direction: column;
        padding: 0.375rem;
        max-width: 100%;
    }
    .gc-page-container .tool-output-column {
        order: 1;
        position: relative;
        top: auto;
        width: 100%;
        max-width: 100%;
    }
    .gc-page-container .tool-input-column {
        order: 2;
        width: 100%;
        max-width: 100%;
        max-height: none;
        overflow-y: visible;
        position: relative;
        top: auto;
    }
}

/* ========================================
   GRAPH: Fill output, allow Plotly zoom/pan
   ======================================== */
.gc-graph-card {
    background: var(--bg-primary, #ffffff);
    border: 1px solid var(--border, #e2e8f0);
    border-radius: var(--gc-radius);
    /* DO NOT set overflow:hidden — it clips Plotly modebar & tooltips */
    overflow: visible;
    box-shadow: var(--gc-shadow-card);
    display: flex;
    flex-direction: column;
    height: calc(100vh - 200px);
    min-height: 480px;
    transition: box-shadow var(--gc-transition);
}
.gc-graph-card:hover {
    box-shadow: var(--gc-shadow-card-hover);
}
.gc-graph-card #graph {
    flex: 1;
    width: 100%;
    min-height: 0; /* allow shrink in flex */
}
/* Let Plotly toolbar float above card edge */
.gc-graph-card .modebar-container {
    z-index: 10;
}

/* Graph toolbar */
.gc-graph-toolbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.5rem 0.75rem;
    border-bottom: 1px solid var(--border, #e2e8f0);
    background: var(--bg-secondary, #f8fafc);
    border-radius: var(--gc-radius) var(--gc-radius) 0 0;
    flex-shrink: 0;
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
}
.gc-graph-toolbar-title {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--gc-tool);
}
.gc-graph-toolbar-title i { margin-right: 0.25rem; }
.gc-graph-toolbar-actions {
    display: flex;
    gap: 0.25rem;
}
.gc-toolbar-btn {
    width: 30px;
    height: 30px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--border, #e2e8f0);
    border-radius: var(--gc-radius-xs);
    background: var(--bg-primary, #ffffff);
    color: var(--text-secondary, #64748b);
    cursor: pointer;
    font-size: 0.6875rem;
    transition: all var(--gc-transition);
}
.gc-toolbar-btn:hover {
    border-color: var(--gc-tool);
    color: var(--gc-tool);
    background: var(--gc-light);
    transform: translateY(-1px);
    box-shadow: 0 2px 6px rgba(139,92,246,0.15);
}
.gc-toolbar-btn:active {
    transform: translateY(0) scale(0.96);
}
[data-theme="dark"] .gc-graph-toolbar {
    background: #111827;
    border-color: #2d3a4d;
}
[data-theme="dark"] .gc-toolbar-btn {
    background: var(--bg-secondary, #1e293b);
    border-color: var(--border, #475569);
    color: var(--text-secondary, #94a3b8);
}
[data-theme="dark"] .gc-toolbar-btn:hover {
    border-color: #a78bfa;
    color: #a78bfa;
}
/* ========================================
   MOBILE: Tablet (≤900px)
   ======================================== */
@media (max-width: 900px) {
    .gc-graph-card {
        height: 55vh;
        min-height: 300px;
        position: static;
    }
    .gc-page-container.tool-page-container {
        padding: 0.5rem;
        gap: 0.5rem;
        min-height: auto;
    }
    .gc-page-container .tool-card + .tool-card,
    .gc-page-container .tool-card[style*="margin-top"] {
        margin-top: 0.5rem !important;
    }
    /* Card internals */
    .gc-page-container .tool-card-body { padding: 0.625rem; }
    .gc-page-container .tool-card-header { padding: 0.5rem 0.75rem; font-size: 0.8125rem; }
    .gc-page-container .tool-section-content { padding: 0.5rem; }
    .gc-page-container .tool-section-header { padding: 0.5rem 0.625rem; font-size: 0.75rem; }
}

/* ========================================
   MOBILE: Phone (≤480px) — aggressive compaction
   ======================================== */
@media (max-width: 480px) {
    /* Graph */
    .gc-graph-card {
        height: 50vh;
        min-height: 250px;
        border-radius: 0.5rem;
    }
    .gc-graph-toolbar { padding: 0.25rem 0.5rem; }
    .gc-graph-toolbar-title { font-size: 0.6875rem; }
    .gc-toolbar-btn { width: 24px; height: 24px; font-size: 0.6rem; }

    /* Main container */
    .gc-page-container.tool-page-container {
        padding: 0.25rem;
        gap: 0.25rem;
        min-height: auto;
    }

    /* Card internals */
    .gc-page-container .tool-card-body { padding: 0.375rem; }
    .gc-page-container .tool-card-header { padding: 0.375rem 0.5rem; font-size: 0.75rem; }
    .gc-page-container .tool-section-content { padding: 0.375rem; }
    .gc-page-container .tool-section-header { padding: 0.375rem 0.5rem; font-size: 0.6875rem; }
    .gc-page-container .tool-card + .tool-card,
    .gc-page-container .tool-card[style*="margin-top"] {
        margin-top: 0.25rem !important;
    }

    /* Expression items */
    .gc-page-container .expression-item {
        margin-bottom: 0.25rem;
    }
    .gc-page-container .gc-expr-body {
        padding: 0.3rem 0.4rem;
    }
    .gc-page-container .expression-input {
        font-size: 0.9375rem;
        padding: 0.4rem 0.5rem;
        border-width: 1.5px;
        box-shadow: none;
    }
    .gc-page-container .gc-toggle-label { font-size: 0.7rem; }
    .gc-page-container .gc-calc-drawer-row { gap: 0.1rem 0.2rem; }
    .gc-page-container .gc-color-swatch { min-height: 24px; }
    .gc-page-container .gc-expr-left-rail { width: 18px; }
    .gc-page-container .gc-drag-handle { height: 12px; font-size: 0.4rem; }
    .gc-page-container .gc-delete-btn { padding: 0.2rem; font-size: 0.6rem; }
    .gc-page-container .gc-numeric-result { font-size: 0.7rem; }

    /* Preset chips */
    .gc-preset-chip { padding: 0.2rem 0.4rem; font-size: 0.6875rem; }
    .gc-preset-category { margin-bottom: 0.25rem; }
    .gc-preset-category-label { font-size: 0.6875rem; margin-bottom: 0.15rem; }

    /* Action buttons */
    .gc-sidebar-actions { gap: 0.25rem; }
    .gc-sidebar-actions .gc-action-btn { padding: 0.25rem 0.35rem; font-size: 0.6875rem; }
    .gc-btn-add { padding: 0.35rem; font-size: 0.75rem; margin-top: 0.25rem; }
}

/* ========================================
   EXPRESSION ITEMS: Desmos-style compact
   ======================================== */
.gc-page-container .expression-item {
    background: var(--bg-secondary, #f8f9fa);
    display: flex;
    flex-wrap: wrap;
    gap: 0;
    padding: 0;
    margin-bottom: 0.5rem;
    border-radius: var(--gc-radius-sm);
    /* NO overflow:hidden — clips MathQuill popups, same as gc-graph-card */
    position: relative;
    box-shadow: var(--gc-glow);
    transition: box-shadow var(--gc-transition), transform var(--gc-transition);
}
.gc-page-container .expression-item:hover {
    box-shadow: var(--gc-shadow-card);
}
.gc-page-container .expression-item:focus-within {
    box-shadow: var(--gc-shadow-card-hover);
}

/* Zone 1: Color rail (left strip) + drag handle */
.gc-page-container .gc-expr-left-rail {
    width: 24px;
    flex-shrink: 0;
    position: relative;
    cursor: pointer;
    border-radius: 0.375rem 0 0 0.375rem;
    display: flex;
    flex-direction: column;
    align-items: center;
}
.gc-page-container .gc-drag-handle {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
    height: 16px;
    cursor: grab;
    color: var(--text-muted, #94a3b8);
    font-size: 0.5rem;
    opacity: 0;
    transition: opacity 0.15s;
    flex-shrink: 0;
    background: rgba(0,0,0,0.03);
    border-radius: 0.375rem 0 0 0;
}
.gc-page-container .expression-item:hover .gc-drag-handle { opacity: 1; }
.gc-page-container .gc-drag-handle:active { cursor: grabbing; }
.gc-page-container .gc-color-swatch {
    display: block;
    width: 100%;
    flex: 1;
    min-height: 28px;
    border: none;
    padding: 0;
    cursor: pointer;
    border-radius: 0 0 0 0.375rem;
    transition: filter 0.15s;
}
.gc-page-container .gc-color-swatch:hover { filter: brightness(1.15); }
.gc-page-container .gc-color-swatch input[type="color"] {
    position: absolute;
    opacity: 0;
    width: 0;
    height: 0;
    pointer-events: none;
}

/* Drag states */
.gc-page-container .expression-item.gc-dragging {
    opacity: 0.4;
    box-shadow: 0 2px 12px rgba(139, 92, 246, 0.3);
}
.gc-page-container .gc-drag-placeholder {
    height: 4px;
    background: var(--gc-tool);
    border-radius: 2px;
    margin: 0.25rem 0;
    transition: height 0.15s;
}

/* Zone 2: Main body */
.gc-page-container .gc-expr-body {
    flex: 1 1 0;
    min-width: 0;
    padding: 0.4rem 0.5rem;
}
/* Top row: input + delete button side by side */
.gc-page-container .gc-expr-top-row {
    display: flex;
    align-items: flex-start;
    gap: 0.25rem;
}
.gc-page-container .gc-expr-input-wrap {
    flex: 1;
    min-width: 0;
}
/* Always-visible delete button */
.gc-page-container .gc-delete-btn {
    flex-shrink: 0;
    border: none;
    background: transparent;
    color: var(--text-muted, #c4c4c4);
    padding: 0.3rem;
    border-radius: 0.25rem;
    cursor: pointer;
    font-size: 0.7rem;
    line-height: 1;
    transition: color 0.15s, background 0.15s;
    margin-top: 0.15rem;
}
.gc-page-container .gc-delete-btn:hover {
    background: #fef2f2;
    color: #dc3545;
}

/* Numeric result (Desmos-style: "= 5") */
.gc-page-container .gc-numeric-result {
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--gc-tool);
    padding: 0.15rem 0;
    font-family: 'JetBrains Mono', monospace;
}

/* Expression input — MUST stand out as the primary interaction target */
.gc-page-container .expression-input {
    width: 100%;
    font-family: 'JetBrains Mono', 'Courier New', monospace;
    font-size: 1rem;
    padding: 0.5rem 0.75rem;
    border: 2px solid var(--gc-tool);
    border-radius: var(--gc-radius-xs);
    background: #faf8ff;
    color: var(--text-primary, #0f172a);
    transition: border-color var(--gc-transition), box-shadow var(--gc-transition), background var(--gc-transition);
    box-shadow: 0 0 0 3px rgba(139, 92, 246, 0.08);
    line-height: 1.4;
}
.gc-page-container .expression-input::placeholder {
    color: #a78bfa;
    font-style: italic;
    font-weight: 400;
    opacity: 0.7;
}
.gc-page-container .expression-input:focus {
    outline: none;
    border-color: var(--gc-tool-dark);
    background: #ffffff;
    box-shadow: 0 0 0 3px rgba(139, 92, 246, 0.18), 0 2px 8px rgba(139, 92, 246, 0.1);
}
/* Empty input — pulsing hint so user knows where to type */
.gc-page-container .expression-input:placeholder-shown:not(:focus) {
    animation: gc-input-hint 2.5s ease-in-out infinite;
}
@keyframes gc-input-hint {
    0%, 100% { box-shadow: 0 0 0 3px rgba(139, 92, 246, 0.08); }
    50% { box-shadow: 0 0 0 4px rgba(139, 92, 246, 0.18); }
}

/* ========================================
   MathQuill rich input field
   ======================================== */
.gc-page-container .gc-mq-wrapper {
    position: relative;
}
.gc-page-container .gc-mq-field {
    width: 100%;
    min-height: 2.25rem;
    font-size: 1.05rem;
    padding: 0.4rem 0.75rem;
    border: 2px solid var(--gc-tool);
    border-radius: 0.375rem;
    background: #faf8ff;
    color: var(--text-primary, #0f172a);
    transition: border-color 0.2s, box-shadow 0.2s, background 0.2s;
    box-shadow: 0 0 0 3px rgba(139, 92, 246, 0.08);
    cursor: text;
}
/* Override MathQuill internal border/padding */
.gc-page-container .gc-mq-field .mq-editable-field {
    border: none !important;
    box-shadow: none !important;
    padding: 0 !important;
    min-height: unset !important;
}
.gc-page-container .gc-mq-field .mq-editable-field .mq-root-block {
    padding: 0;
}
.gc-page-container .gc-mq-field:focus-within {
    outline: none;
    border-color: var(--gc-tool-dark);
    background: #ffffff;
    box-shadow: 0 0 0 3px rgba(139, 92, 246, 0.18), 0 2px 8px rgba(139, 92, 246, 0.1);
}
/* Placeholder text for empty MathQuill field */
.gc-page-container .gc-mq-field .mq-editable-field.mq-empty::after {
    content: attr(data-mq-placeholder);
    color: #a78bfa;
    font-style: italic;
    font-weight: 400;
    opacity: 0.7;
    pointer-events: none;
    font-family: 'Inter', sans-serif;
    font-size: 0.875rem;
}
/* Toggle between MathQuill and plain text */
.gc-page-container .gc-input-mode-toggle {
    position: absolute;
    top: 0.35rem;
    right: 0.4rem;
    font-size: 0.65rem;
    padding: 0.1rem 0.35rem;
    border: 1px solid #d4d4d8;
    border-radius: 0.25rem;
    background: #f4f4f5;
    color: #71717a;
    cursor: pointer;
    z-index: 2;
    line-height: 1.3;
    transition: background 0.15s, color 0.15s;
}
.gc-page-container .gc-input-mode-toggle:hover {
    background: #e4e4e7;
    color: #3f3f46;
}
/* Dark mode MathQuill */
[data-theme="dark"] .gc-page-container .gc-mq-field {
    background: #1a1432;
    border-color: #6d5ca0;
    color: var(--text-primary, #e5e7eb);
    box-shadow: 0 0 0 2px rgba(167, 139, 250, 0.1);
}
[data-theme="dark"] .gc-page-container .gc-mq-field:focus-within {
    border-color: #c4b5fd;
    background: #1e1538;
    box-shadow: 0 0 0 3px rgba(167, 139, 250, 0.2), 0 2px 8px rgba(167, 139, 250, 0.12);
}
[data-theme="dark"] .gc-page-container .gc-mq-field .mq-editable-field.mq-empty::after {
    color: #7c6cb0;
}
[data-theme="dark"] .gc-page-container .gc-input-mode-toggle {
    background: #2a2040;
    border-color: #4a3d6a;
    color: #a78bfa;
}
[data-theme="dark"] .gc-page-container .gc-input-mode-toggle:hover {
    background: #352960;
    color: #c4b5fd;
}
/* MathQuill cursor and selection colors */
.gc-page-container .gc-mq-field .mq-cursor {
    border-color: var(--gc-tool, #8b5cf6);
}
.gc-page-container .gc-mq-field .mq-selection .mq-matrixed {
    background: rgba(139, 92, 246, 0.2);
}
.gc-page-container .gc-mq-field .mq-selection .mq-matrixed-container {
    filter: none;
}
/* Dark mode: fraction bar, sqrt bar, and other borders visible */
[data-theme="dark"] .gc-page-container .gc-mq-field .mq-fraction .mq-fraction-inner {
    border-top-color: var(--text-primary, #e5e7eb);
}
[data-theme="dark"] .gc-page-container .gc-mq-field .mq-sqrt-prefix {
    color: var(--text-primary, #e5e7eb);
}
[data-theme="dark"] .gc-page-container .gc-mq-field .mq-sqrt-stem {
    border-color: var(--text-primary, #e5e7eb);
}

/* ========================================
   Sample chips: hidden by default, show on focus
   ======================================== */
.gc-page-container .gc-sample-chips {
    display: flex;
    flex-wrap: wrap;
    gap: 0.25rem;
    margin-top: 0.375rem;
}
.gc-page-container .gc-sample-chips .btn {
    padding: 0.2rem 0.4rem;
    font-size: 0.75rem;
    margin: 0 !important;
}
/* Hide samples until input is focused */
.gc-page-container .gc-on-focus {
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    margin: 0;
    transition: max-height 0.2s ease, opacity 0.15s ease, margin 0.15s ease;
}
.gc-page-container .expression-item:focus-within .gc-on-focus {
    max-height: 120px;
    opacity: 1;
    margin-top: 0.25rem;
}

/* ========================================
   Math preview: hide when empty, compact
   ======================================== */
.gc-page-container .math-preview:empty,
.gc-page-container .math-preview:not(:has(.katex)) {
    display: none;
}

/* ========================================
   Expression meta row: type badge, calc toggle, delete
   (hidden by default, revealed on focus or drawer open)
   ======================================== */
.gc-page-container .gc-expr-meta {
    display: flex;
    align-items: center;
    gap: 0.375rem;
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    margin: 0;
    transition: max-height 0.18s ease, opacity 0.15s ease, margin 0.12s ease;
}
.gc-page-container .expression-item:focus-within .gc-expr-meta,
.gc-page-container .expression-item.gc-calc-open .gc-expr-meta,
.gc-page-container .expression-item:hover .gc-expr-meta {
    max-height: 32px;
    opacity: 1;
    margin-top: 0.3rem;
}

/* Type badge */
.gc-page-container .gc-type-badge {
    font-size: 0.6rem;
    font-weight: 700;
    font-family: 'JetBrains Mono', monospace;
    padding: 0.1rem 0.3rem;
    border-radius: 0.2rem;
    border: 1px solid var(--border, #e2e8f0);
    background: transparent;
    color: var(--gc-tool);
    cursor: pointer;
    white-space: nowrap;
    text-transform: uppercase;
    letter-spacing: 0.02em;
    transition: all 0.15s;
}
.gc-page-container .gc-type-badge:hover {
    background: var(--gc-light);
    border-color: var(--gc-tool);
}

/* Type badge is a positioned parent for the hidden select overlay */
.gc-page-container .gc-type-badge {
    position: relative;
}
/* Hidden type select overlays the badge so showPicker/click work natively */
.gc-page-container .gc-type-select-hidden {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    cursor: pointer;
    border: 0;
    padding: 0;
    margin: 0;
}

/* Calculus drawer toggle button */
.gc-page-container .gc-calc-toggle-btn {
    font-size: 0.65rem;
    padding: 0.1rem 0.3rem;
    border: 1px solid var(--border, #e2e8f0);
    border-radius: 0.25rem;
    background: transparent;
    color: var(--text-secondary, #64748b);
    cursor: pointer;
    transition: all 0.15s;
}
.gc-page-container .gc-calc-toggle-btn:hover {
    color: var(--gc-tool);
    border-color: var(--gc-tool);
    background: var(--gc-light);
}
.gc-page-container .gc-calc-open .gc-calc-toggle-btn {
    color: var(--gc-tool);
    background: var(--gc-light);
    border-color: var(--gc-tool);
}

/* LaTeX copy btn in meta row */
.gc-page-container .gc-latex-copy-btn {
    font-size: 0.6rem;
    font-weight: 600;
    padding: 0.1rem 0.3rem;
    border: 1px solid var(--border, #e2e8f0);
    border-radius: 0.2rem;
    background: transparent;
    color: var(--text-muted, #94a3b8);
    cursor: pointer;
    transition: all 0.15s;
}
.gc-page-container .gc-latex-copy-btn:hover {
    color: var(--gc-tool);
    border-color: var(--gc-tool);
}

/* ========================================
   Calculus drawer: hidden by default
   ======================================== */
.gc-page-container .gc-calc-drawer {
    width: 100%;
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    transition: max-height 0.22s ease, opacity 0.18s ease, padding 0.18s ease;
    padding: 0 0.5rem;
}
.gc-page-container .gc-calc-open .gc-calc-drawer {
    max-height: 250px;
    opacity: 1;
    padding: 0.375rem 0.5rem;
    border-top: 1px solid var(--border, #e2e8f0);
}
.gc-page-container .gc-calc-drawer-row {
    display: flex;
    flex-wrap: wrap;
    gap: 0.125rem 0.3rem;
    padding: 0.15rem 0;
}

/* Toggle labels (shared by calc drawer rows) */
.gc-page-container .gc-toggle-label {
    display: inline-flex;
    align-items: center;
    gap: 0.2rem;
    font-size: 0.75rem;
    color: var(--text-secondary, #64748b);
    cursor: pointer;
    user-select: none;
    white-space: nowrap;
    padding: 0.1rem 0.2rem;
    border-radius: 0.25rem;
    transition: background 0.15s, color 0.15s;
}
.gc-page-container .gc-toggle-label:hover {
    background: var(--gc-light, #f5f3ff);
    color: var(--gc-tool);
}

/* ========================================
   Math preview: compact, no label
   ======================================== */
.gc-page-container .math-preview {
    background: var(--bg-primary, white);
    padding: 0.3rem 0.5rem;
    border-radius: 0.25rem;
    margin-top: 0.375rem;
    border: 1px solid var(--border, #e0e0e0);
    font-size: 0.875rem;
}
.gc-page-container .math-preview .katex { font-size: 0.9em; }
.gc-page-container .color-picker {
    width: 24px;
    height: 24px;
    border: none;
    border-radius: 0.25rem;
    cursor: pointer;
    padding: 0;
    flex-shrink: 0;
}
.gc-page-container .plot-type-select {
    font-size: 0.8125rem;
    padding: 0.25rem 1.75rem 0.25rem 0.5rem;
    border-radius: 0.25rem;
    border: 1px solid var(--border, #ddd);
    background: var(--bg-primary, white) url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16'%3e%3cpath fill='none' stroke='%23343a40' stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='m2 5 6 6 6-6'/%3e%3c/svg%3e") no-repeat right 0.5rem center/8px 8px;
    color: var(--text-primary, #0f172a);
    -webkit-appearance: none;
    appearance: none;
    cursor: pointer;
}

/* ========================================
   Compact form check inputs
   ======================================== */
.gc-page-container .form-check-input {
    width: 0.9375rem;
    height: 0.9375rem;
    accent-color: var(--gc-tool);
    margin: 0;
    cursor: pointer;
    flex-shrink: 0;
}

/* Integration & Riemann controls */
.gc-page-container [id^="integration-controls-"] {
    font-size: 0.8125rem;
    padding: 0.375rem 0;
}
.gc-page-container [id^="integration-controls-"] .text-muted {
    font-size: 0.75rem;
    color: var(--text-secondary, #64748b);
}
.gc-page-container [id^="integration-controls-"] .form-control-sm,
.gc-page-container [id^="integration-controls-"] .form-select-sm {
    font-size: 0.8125rem;
    padding: 0.25rem 0.375rem;
    border-radius: 0.25rem;
}

/* ========================================
   Sidebar: stats, table, range, sliders
   ======================================== */
.gc-page-container .stats-output {
    background: var(--gc-light);
    padding: 0.5rem;
    border-radius: 0.25rem;
    margin-top: 0.375rem;
    font-size: 0.75rem;
    font-family: 'Courier New', monospace;
    line-height: 1.5;
}
.gc-page-container .table-input {
    width: 100%;
    margin-top: 0.25rem;
    font-family: 'Courier New', monospace;
    font-size: 0.75rem;
}
.gc-page-container .range-input {
    width: 100%;
    font-size: 0.8125rem;
    padding: 0.25rem 0.375rem;
    margin-top: 0.25rem;
}
/* ========================================
   SLIDERS & ANIMATION CONTROLS
   Engine generates .form-range, .form-select,
   animation play/speed inside sliders-container-{id}
   ======================================== */
.gc-page-container [id^="sliders-container-"] {
    margin-top: 0.375rem;
}
/* Parameter sliders */
.gc-page-container .form-range,
.gc-page-container [id^="sliders-container-"] input[type="range"] {
    -webkit-appearance: none;
    appearance: none;
    width: 100%;
    height: 4px;
    background: var(--border, #e2e8f0);
    border-radius: 2px;
    outline: none;
    cursor: pointer;
    accent-color: var(--gc-tool);
}
.gc-page-container .form-range::-webkit-slider-thumb,
.gc-page-container [id^="sliders-container-"] input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 14px;
    height: 14px;
    border-radius: 50%;
    background: var(--gc-tool);
    border: 2px solid #fff;
    box-shadow: 0 1px 3px rgba(0,0,0,0.2);
    cursor: pointer;
}
.gc-page-container .form-range::-moz-range-thumb {
    width: 14px;
    height: 14px;
    border-radius: 50%;
    background: var(--gc-tool);
    border: 2px solid #fff;
    box-shadow: 0 1px 3px rgba(0,0,0,0.2);
    cursor: pointer;
}
/* Animation controls container (engine uses inline bg #f0f0f0) */
.gc-page-container [id^="sliders-container-"] > .mt-3.p-2 {
    background: var(--gc-light) !important;
    border: 1px solid var(--border, #e2e8f0);
    border-radius: 0.375rem;
    padding: 0.375rem 0.5rem !important;
}
.gc-page-container [id^="sliders-container-"] > .mt-3.p-2 > small {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.04em;
    color: var(--gc-tool);
}
/* Speed dropdown */
.gc-page-container .form-select,
.gc-page-container .form-select-sm {
    display: inline-block;
    padding: 0.25rem 1.75rem 0.25rem 0.5rem;
    font-size: 0.8125rem;
    font-weight: 500;
    border: 1px solid var(--border, #dee2e6);
    border-radius: 0.25rem;
    background: var(--bg-primary, #fff) url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16'%3e%3cpath fill='none' stroke='%23343a40' stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='m2 5 6 6 6-6'/%3e%3c/svg%3e") no-repeat right 0.5rem center/8px 8px;
    color: var(--text-primary, #212529);
    cursor: pointer;
    -webkit-appearance: none;
    appearance: none;
    transition: border-color 0.15s;
}
.gc-page-container .form-select:focus {
    border-color: var(--gc-tool);
    outline: 0;
    box-shadow: 0 0 0 2px rgba(139, 92, 246, 0.1);
}
/* Align-self utility */
.gc-page-container .align-self-center { align-self: center; }

/* ========================================
   Add Expression button
   ======================================== */
.gc-btn-add {
    width: 100%;
    margin-top: 0.375rem;
    padding: 0.375rem 0.5rem;
    font-weight: 600;
    font-size: 0.8rem;
    border: none;
    border-radius: var(--gc-radius-xs);
    cursor: pointer;
    background: var(--gc-gradient);
    color: white;
    transition: all var(--gc-transition);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.25rem;
    box-shadow: 0 1px 3px rgba(139,92,246,0.2);
}
.gc-btn-add:hover {
    box-shadow: 0 4px 12px rgba(139,92,246,0.3);
    transform: translateY(-1px);
}
.gc-btn-add:active {
    transform: translateY(0) scale(0.98);
    box-shadow: 0 1px 2px rgba(139,92,246,0.2);
}

/* ========================================
   Preset chips
   ======================================== */
.gc-preset-category {
    margin-bottom: 0.5rem;
    padding-bottom: 0.5rem;
    border-bottom: 1px solid var(--border, #e9ecef);
}
.gc-preset-category:last-child {
    border-bottom: none;
    margin-bottom: 0;
    padding-bottom: 0;
}
.gc-preset-category-label {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted, #64748b);
    margin-bottom: 0.25rem;
}
.gc-preset-chips {
    display: flex;
    flex-wrap: wrap;
    gap: 0.25rem;
}
.gc-preset-chip {
    padding: 0.25rem 0.5rem;
    font-size: 0.75rem;
    font-weight: 500;
    border-radius: 2rem;
    border: 1px solid var(--border, #e2e8f0);
    background: var(--bg-primary, #ffffff);
    color: var(--text-secondary, #475569);
    cursor: pointer;
    transition: all var(--gc-transition);
    white-space: nowrap;
    line-height: 1.3;
}
.gc-preset-chip:hover {
    background: var(--gc-light);
    color: var(--gc-tool);
    border-color: rgba(139,92,246,0.4);
    transform: translateY(-1px);
    box-shadow: 0 2px 8px rgba(139,92,246,0.12);
}
.gc-preset-chip:active {
    transform: translateY(0) scale(0.97);
    border-color: var(--gc-tool);
}

/* ========================================
   Sidebar action buttons (settings/export)
   ======================================== */
.gc-sidebar-actions {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.25rem;
}
.gc-sidebar-actions .gc-action-btn {
    padding: 0.35rem 0.5rem;
    font-size: 0.75rem;
    font-weight: 500;
    border: 1px solid var(--border, #e2e8f0);
    border-radius: 0.25rem;
    background: var(--bg-primary, #ffffff);
    color: var(--text-primary, #0f172a);
    cursor: pointer;
    transition: all 0.15s;
    display: flex;
    align-items: center;
    gap: 0.25rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}
.gc-sidebar-actions .gc-action-btn:hover {
    border-color: var(--gc-tool);
    color: var(--gc-tool);
}
.gc-sidebar-actions .gc-action-btn i {
    width: 12px;
    text-align: center;
    flex-shrink: 0;
}
/* Full width for single-row items */
.gc-sidebar-actions .gc-action-btn.gc-full { grid-column: 1 / -1; }

/* ========================================
   Quick guide
   ======================================== */
.gc-quick-guide {
    font-size: 0.8125rem;
    line-height: 1.6;
    color: var(--text-secondary, #475569);
    columns: 2;
    column-gap: 0.75rem;
}
.gc-quick-guide strong { color: var(--text-primary, #0f172a); }
@media (max-width: 900px) {
    .gc-quick-guide { columns: 1; }
}

/* ========================================
   BOOTSTRAP SHIM (scoped to .gc-page-container)
   Engine.js dynamically generates these classes
   ======================================== */

/* Form Controls */
.gc-page-container .form-control {
    display: block;
    width: 100%;
    padding: 0.3rem 0.4rem;
    font-size: 0.8125rem;
    border: 1px solid var(--border, #dee2e6);
    border-radius: 0.25rem;
    background: var(--bg-primary, #fff);
    color: var(--text-primary, #212529);
    transition: border-color 0.15s, box-shadow 0.15s;
}
.gc-page-container .form-control:focus {
    border-color: var(--gc-tool);
    outline: 0;
    box-shadow: 0 0 0 2px rgba(139, 92, 246, 0.1);
}
.gc-page-container .form-control-sm {
    padding: 0.3rem 0.4rem;
    font-size: 0.8125rem;
}

/* Buttons */
.gc-page-container .btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.25rem;
    padding: 0.35rem 0.625rem;
    font-size: 0.8125rem;
    font-weight: 500;
    border-radius: 0.25rem;
    cursor: pointer;
    transition: all 0.15s;
    border: 1px solid transparent;
    text-decoration: none;
}
.gc-page-container .btn-sm {
    padding: 0.2rem 0.4rem;
    font-size: 0.75rem;
}
.gc-page-container .btn-primary {
    background: var(--gc-tool); color: #fff; border-color: var(--gc-tool);
}
.gc-page-container .btn-primary:hover { opacity: 0.9; }
.gc-page-container .btn-secondary {
    background: var(--bg-secondary, #e2e8f0); color: var(--text-primary, #334155); border-color: var(--border, #cbd5e1);
}
.gc-page-container .btn-secondary:hover { background: var(--border, #cbd5e1); }
.gc-page-container .btn-success { background: #16a34a; color: #fff; border-color: #16a34a; }
.gc-page-container .btn-info { background: #0ea5e9; color: #fff; border-color: #0ea5e9; }
.gc-page-container .btn-warning { background: #f59e0b; color: #000; border-color: #f59e0b; }
.gc-page-container .btn-danger { background: #dc3545; color: #fff; border-color: #dc3545; }
.gc-page-container .btn-outline-secondary {
    background: transparent;
    color: var(--text-secondary, #64748b);
    border-color: var(--border, #cbd5e1);
}
.gc-page-container .btn-outline-secondary:hover {
    background: var(--bg-secondary, #f1f5f9);
    color: var(--gc-tool);
    border-color: var(--gc-tool);
}
.gc-page-container .btn-outline-primary {
    background: transparent;
    color: var(--gc-tool);
    border-color: var(--gc-tool);
}
.gc-page-container .btn-outline-primary:hover {
    background: var(--gc-tool);
    color: #fff;
}
.gc-page-container .btn-outline-light {
    background: transparent;
    color: var(--text-primary, #f8f9fa);
    border-color: var(--border, #f8f9fa);
}

/* Spacing */
.gc-page-container .ms-1 { margin-left: 0.25rem; }
.gc-page-container .ms-2 { margin-left: 0.5rem; }
.gc-page-container .mt-1 { margin-top: 0.25rem; }
.gc-page-container .mt-2 { margin-top: 0.5rem; }
.gc-page-container .mt-3 { margin-top: 1rem; }
.gc-page-container .mb-1 { margin-bottom: 0.25rem; }
.gc-page-container .mb-2 { margin-bottom: 0.5rem; }
.gc-page-container .mb-3 { margin-bottom: 1rem; }
.gc-page-container .me-1 { margin-right: 0.25rem; }
.gc-page-container .me-2 { margin-right: 0.5rem; }
.gc-page-container .p-2 { padding: 0.375rem; }

/* Flex */
.gc-page-container .d-flex { display: flex; }
.gc-page-container .d-grid { display: grid; }
.gc-page-container .d-none { display: none; }
.gc-page-container .d-block { display: block; }
.gc-page-container .d-inline { display: inline; }
.gc-page-container .flex-wrap { flex-wrap: wrap; }
.gc-page-container .align-items-center { align-items: center; }
.gc-page-container .justify-content-between { justify-content: space-between; }
.gc-page-container .gap-1 { gap: 0.25rem; }
.gc-page-container .gap-2 { gap: 0.5rem; }
.gc-page-container .gap-3 { gap: 1rem; }
.gc-page-container .w-100 { width: 100%; }
.gc-page-container .text-muted { color: var(--text-muted, #94a3b8); font-size: 0.75rem; }

/* Form Label */
.gc-page-container .form-label {
    display: block;
    font-weight: 500;
    margin-bottom: 0.25rem;
    color: var(--text-primary, #0f172a);
    font-size: 0.8125rem;
}

/* Alert */
.gc-page-container .alert {
    padding: 0.5rem 0.625rem;
    border-radius: 0.375rem;
    font-size: 0.8125rem;
    margin-bottom: 0.5rem;
}
.gc-page-container .alert-danger {
    background: #fef2f2; color: #991b1b; border: 1px solid #fecaca;
}

/* ========================================
   DARK MODE
   ======================================== */

/* --- Cards: slightly lighter than page, with visible border --- */
[data-theme="dark"] .gc-page-container .tool-card {
    background: #151d2b;
    border-color: #2d3a4d;
    box-shadow: 0 1px 4px rgba(0, 0, 0, 0.3);
}

/* --- Section headers: subtle bg so they stand out as clickable --- */
[data-theme="dark"] .gc-page-container .tool-section-header {
    background: #1a2436;
    border-bottom: 1px solid #2d3a4d;
}
[data-theme="dark"] .gc-page-container .tool-section-header:hover {
    background: rgba(139, 92, 246, 0.12);
}

/* --- Section content: darker inset look, visible top border --- */
[data-theme="dark"] .gc-page-container .tool-section-content {
    background: #111827;
    border-top: 1px solid #2d3a4d;
}

/* --- Card header (Expressions) keeps gradient, just refine border --- */
[data-theme="dark"] .gc-page-container .tool-card-header {
    border-bottom: 1px solid rgba(139, 92, 246, 0.3);
}

/* --- Card body: match card bg --- */
[data-theme="dark"] .gc-page-container .tool-card-body {
    background: #151d2b;
}

/* --- Preset categories: visible separator between groups --- */
[data-theme="dark"] .gc-page-container .gc-preset-category {
    padding-bottom: 0.5rem;
    margin-bottom: 0.5rem;
    border-bottom: 1px solid #1f2937;
}
[data-theme="dark"] .gc-page-container .gc-preset-category:last-child {
    border-bottom: none;
    margin-bottom: 0;
    padding-bottom: 0;
}

/* --- Expression items: inset darker than card-body --- */
[data-theme="dark"] .gc-page-container .expression-item {
    background: #0d1320;
    border: 1px solid #1f2937;
}
/* Dark: new layout elements */
[data-theme="dark"] .gc-page-container .gc-type-badge {
    border-color: #475569;
    color: #a78bfa;
}
[data-theme="dark"] .gc-page-container .gc-type-badge:hover {
    background: rgba(139, 92, 246, 0.12);
    border-color: #a78bfa;
}
[data-theme="dark"] .gc-page-container .gc-calc-toggle-btn {
    border-color: #475569;
    color: #94a3b8;
}
[data-theme="dark"] .gc-page-container .gc-calc-toggle-btn:hover,
[data-theme="dark"] .gc-page-container .gc-calc-open .gc-calc-toggle-btn {
    color: #c4b5fd;
    background: rgba(139, 92, 246, 0.15);
    border-color: #a78bfa;
}
[data-theme="dark"] .gc-page-container .gc-drag-handle {
    color: #64748b;
    background: rgba(255,255,255,0.03);
}
[data-theme="dark"] .gc-page-container .gc-delete-btn {
    color: #64748b;
}
[data-theme="dark"] .gc-page-container .gc-delete-btn:hover {
    background: rgba(239, 68, 68, 0.15);
    color: #fca5a5;
}
[data-theme="dark"] .gc-page-container .gc-numeric-result {
    color: #a78bfa;
}
[data-theme="dark"] .gc-page-container .gc-drag-placeholder {
    background: #a78bfa;
}
[data-theme="dark"] .gc-page-container .gc-latex-copy-btn {
    color: #94a3b8;
    border-color: #475569;
}
[data-theme="dark"] .gc-page-container .gc-latex-copy-btn:hover {
    color: #c4b5fd;
    border-color: #a78bfa;
}
[data-theme="dark"] .gc-page-container .gc-calc-open .gc-calc-drawer {
    border-top-color: #2d3a4d;
}
[data-theme="dark"] .gc-page-container .expression-input {
    background: #1a1432;
    border-color: #6d5ca0;
    color: var(--text-primary, #e5e7eb);
    box-shadow: 0 0 0 2px rgba(167, 139, 250, 0.1);
}
[data-theme="dark"] .gc-page-container .expression-input::placeholder {
    color: #7c6cb0;
}
[data-theme="dark"] .gc-page-container .expression-input:focus {
    border-color: #c4b5fd;
    background: #1e1538;
    box-shadow: 0 0 0 3px rgba(167, 139, 250, 0.2), 0 2px 8px rgba(167, 139, 250, 0.12);
}
[data-theme="dark"] .gc-page-container .expression-input:placeholder-shown:not(:focus) {
    animation: gc-input-hint-dark 2.5s ease-in-out infinite;
}
@keyframes gc-input-hint-dark {
    0%, 100% { box-shadow: 0 0 0 3px rgba(167, 139, 250, 0.1); }
    50% { box-shadow: 0 0 0 4px rgba(167, 139, 250, 0.22); }
}
[data-theme="dark"] .gc-graph-card {
    background: #151d2b;
    border-color: #2d3a4d;
}
[data-theme="dark"] .gc-page-container .form-check-label,
[data-theme="dark"] .gc-page-container label,
[data-theme="dark"] .gc-page-container .form-label {
    color: var(--text-secondary, #94a3b8);
}
[data-theme="dark"] .gc-page-container input,
[data-theme="dark"] .gc-page-container textarea {
    background: var(--gc-input-bg, #1a2332);
    color: var(--text-primary, #e5e7eb);
    border-color: var(--gc-input-border, #475569);
}
/* Selects: reset to plain bg, specific classes (.form-select, .plot-type-select) add their own arrow */
[data-theme="dark"] .gc-page-container select {
    background: var(--gc-input-bg, #1a2332);
    color: var(--text-primary, #e5e7eb);
    border-color: var(--gc-input-border, #475569);
}
[data-theme="dark"] .gc-page-container .form-control {
    background: var(--gc-input-bg, #1a2332);
    color: var(--text-primary, #e5e7eb);
    border-color: var(--gc-input-border, #475569);
}
[data-theme="dark"] .gc-page-container .form-control:focus {
    border-color: var(--gc-input-border-focus, #a78bfa);
    box-shadow: 0 0 0 2px rgba(167, 139, 250, 0.18);
}
[data-theme="dark"] .gc-page-container .btn-secondary {
    background: var(--gc-input-bg, #1a2332);
    color: var(--text-primary, #e2e8f0);
    border-color: var(--gc-input-border, #475569);
}
[data-theme="dark"] .gc-page-container .btn-outline-secondary {
    color: var(--text-secondary, #94a3b8);
    border-color: var(--border, #475569);
}
[data-theme="dark"] .gc-page-container .btn-outline-secondary:hover {
    background: rgba(139, 92, 246, 0.12);
    color: #c4b5fd;
    border-color: #a78bfa;
}
[data-theme="dark"] .gc-btn-add {
    box-shadow: 0 2px 10px rgba(139, 92, 246, 0.35);
    border: 1px solid rgba(139, 92, 246, 0.4);
}
[data-theme="dark"] .gc-preset-chip {
    background: #1e293b;
    border-color: #3b4a5e;
    color: #cbd5e1;
}
[data-theme="dark"] .gc-preset-chip:hover {
    background: var(--gc-tool);
    border-color: var(--gc-tool);
    color: white;
    box-shadow: 0 0 8px rgba(139, 92, 246, 0.3);
}
[data-theme="dark"] .gc-sidebar-actions .gc-action-btn {
    background: #1e293b;
    border-color: #3b4a5e;
    color: #cbd5e1;
}
[data-theme="dark"] .gc-sidebar-actions .gc-action-btn:hover {
    border-color: var(--gc-tool);
    color: var(--gc-tool);
    background: rgba(139, 92, 246, 0.08);
}
[data-theme="dark"] .gc-page-container .stats-output {
    background: rgba(139, 92, 246, 0.08);
    border: 1px solid #2d3a4d;
    color: #cbd5e1;
}
[data-theme="dark"] .gc-page-container .math-preview {
    background: #111827;
    border-color: #2d3a4d;
    color: #e5e7eb;
}
[data-theme="dark"] .gc-page-container .alert-danger {
    background: rgba(239, 68, 68, 0.15);
    color: #fca5a5;
    border-color: rgba(239, 68, 68, 0.3);
}
/* Animation controls dark mode */
[data-theme="dark"] .gc-page-container [id^="sliders-container-"] > .mt-3.p-2 {
    background: rgba(139, 92, 246, 0.1) !important;
    border-color: var(--gc-input-border, #475569);
}
[data-theme="dark"] .gc-page-container .form-range,
[data-theme="dark"] .gc-page-container [id^="sliders-container-"] input[type="range"] {
    background: var(--border, #334155);
}
[data-theme="dark"] .gc-page-container .form-range::-webkit-slider-thumb,
[data-theme="dark"] .gc-page-container [id^="sliders-container-"] input[type="range"]::-webkit-slider-thumb {
    background: #a78bfa;
    border-color: var(--bg-secondary, #1e293b);
}
[data-theme="dark"] .gc-page-container .form-select {
    background: #1a2332 url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16'%3e%3cpath fill='none' stroke='%2394a3b8' stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='m2 5 6 6 6-6'/%3e%3c/svg%3e") no-repeat right 0.5rem center/8px 8px;
    color: var(--text-primary, #e5e7eb);
    border-color: var(--gc-input-border, #475569);
}
[data-theme="dark"] .gc-page-container .form-select:focus {
    border-color: var(--gc-input-border-focus, #a78bfa);
    box-shadow: 0 0 0 2px rgba(167, 139, 250, 0.18);
}

/* Dark: toggle label hover */
[data-theme="dark"] .gc-page-container .gc-toggle-label {
    color: var(--text-secondary, #94a3b8);
}
[data-theme="dark"] .gc-page-container .gc-toggle-label:hover {
    background: rgba(139, 92, 246, 0.15);
    color: #c4b5fd;
}

/* Dark: plot type select */
[data-theme="dark"] .gc-page-container .plot-type-select {
    background: var(--gc-input-bg, #1a2332) url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16'%3e%3cpath fill='none' stroke='%2394a3b8' stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='m2 5 6 6 6-6'/%3e%3c/svg%3e") no-repeat right 0.5rem center/8px 8px;
    color: var(--text-primary, #e5e7eb);
    border-color: var(--gc-input-border, #475569);
}

/* Dark: preset category labels */
[data-theme="dark"] .gc-preset-category-label {
    color: var(--text-muted, #94a3b8);
}

/* Dark: quick guide */
[data-theme="dark"] .gc-quick-guide {
    color: var(--text-secondary, #94a3b8);
}
[data-theme="dark"] .gc-quick-guide strong {
    color: var(--text-primary, #e5e7eb);
}

/* Dark: integration controls text */
[data-theme="dark"] .gc-page-container [id^="integration-controls-"] .text-muted {
    color: var(--text-muted, #94a3b8);
}

/* Dark: sample chips */
[data-theme="dark"] .gc-page-container .gc-sample-chips .btn {
    background: #1e293b;
    color: #94a3b8;
    border-color: #3b4a5e;
}
[data-theme="dark"] .gc-page-container .gc-sample-chips .btn:hover {
    background: rgba(139, 92, 246, 0.15);
    color: #c4b5fd;
    border-color: #a78bfa;
}

/* ========================================
   Expression Error Feedback
   ======================================== */
.gc-page-container .gc-expr-error {
    font-size: 0.75rem;
    color: #ef4444;
    padding: 0.2rem 0.4rem;
    margin-top: 0.25rem;
    border-left: 2px solid #ef4444;
    background: rgba(239, 68, 68, 0.05);
    border-radius: 0 0.25rem 0.25rem 0;
}
[data-theme="dark"] .gc-page-container .gc-expr-error {
    color: #fca5a5;
    background: rgba(239, 68, 68, 0.1);
    border-left-color: #f87171;
}
.gc-page-container .gc-input-error {
    border-color: #ef4444 !important;
    box-shadow: 0 0 0 1px rgba(239, 68, 68, 0.25);
}
[data-theme="dark"] .gc-page-container .gc-input-error {
    border-color: #f87171 !important;
    box-shadow: 0 0 0 1px rgba(248, 113, 113, 0.25);
}

/* ========================================
   Calculus toggles: wrap nicely on mobile
   ======================================== */
.gc-page-container .gc-calculus-toggles {
    display: contents;
}

/* ========================================
   AI Assistant card
   ======================================== */
.gc-ai-card {
    border: 1px solid rgba(139,92,246,0.2);
    box-shadow: var(--gc-shadow-card), 0 0 0 1px rgba(139,92,246,0.06);
    border-radius: var(--gc-radius);
    position: relative;
    transition: box-shadow var(--gc-transition), border-color var(--gc-transition);
}
.gc-ai-card:hover {
    box-shadow: var(--gc-shadow-elevated);
    border-color: rgba(139,92,246,0.35);
}
[data-theme="dark"] .gc-ai-card {
    background: linear-gradient(180deg, rgba(139,92,246,0.06) 0%, transparent 40%);
    border-color: rgba(139,92,246,0.2);
}
[data-theme="dark"] .gc-ai-card:hover {
    border-color: rgba(139,92,246,0.4);
}
.gc-ai-card .gc-ai-header {
    background: linear-gradient(135deg, #8b5cf6 0%, #6366f1 50%, #7c3aed 100%);
    border-radius: calc(var(--gc-radius) - 1px) calc(var(--gc-radius) - 1px) 0 0;
    letter-spacing: 0.01em;
    position: relative;
    overflow: hidden;
}
/* Subtle shimmer effect on header */
.gc-ai-card .gc-ai-header::after {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 200%;
    height: 100%;
    background: linear-gradient(90deg, transparent 40%, rgba(255,255,255,0.08) 50%, transparent 60%);
    animation: gc-ai-shimmer 6s ease-in-out infinite;
}
@keyframes gc-ai-shimmer {
    0%, 100% { transform: translateX(-30%); }
    50% { transform: translateX(30%); }
}
@media (prefers-reduced-motion: reduce) {
    .gc-ai-card .gc-ai-header::after { animation: none; }
}
.gc-ai-sparkle { font-size: 1em; margin-right: 0.25rem; }
.gc-ai-divider {
    height: 1px;
    background: var(--border, #e2e8f0);
    margin: 0.75rem -1rem 0.625rem;
}
[data-theme="dark"] .gc-ai-divider { background: rgba(255,255,255,0.08); }
.gc-ai-explain-btn {
    width: 100%;
    padding: 0.5rem 0.75rem;
    font-size: 0.8125rem;
    font-weight: 600;
    color: #6366f1;
    background: rgba(99, 102, 241, 0.05);
    border: 1.5px dashed rgba(99, 102, 241, 0.3);
    border-radius: var(--gc-radius-sm);
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.375rem;
    transition: all var(--gc-transition);
}
.gc-ai-explain-btn:hover:not(:disabled) {
    background: rgba(99, 102, 241, 0.1);
    border-color: rgba(99, 102, 241, 0.5);
    border-style: solid;
    transform: translateY(-1px);
    box-shadow: 0 2px 8px rgba(99,102,241,0.1);
}
.gc-ai-explain-btn:active:not(:disabled) {
    transform: translateY(0) scale(0.98);
}
.gc-ai-explain-btn:disabled { opacity: 0.6; cursor: not-allowed; }
[data-theme="dark"] .gc-ai-explain-btn {
    color: #a78bfa;
    background: rgba(139, 92, 246, 0.06);
    border-color: rgba(139, 92, 246, 0.3);
}
[data-theme="dark"] .gc-ai-explain-btn:hover:not(:disabled) {
    background: rgba(139, 92, 246, 0.15);
    border-color: rgba(139, 92, 246, 0.5);
    border-style: solid;
}
.gc-ai-input {
    width: 100%;
    padding: 0.625rem 0.75rem;
    font-size: 0.8125rem;
    border: 1.5px solid var(--border, #e2e8f0);
    border-radius: var(--gc-radius-sm);
    resize: vertical;
    transition: border-color var(--gc-transition), box-shadow var(--gc-transition), background var(--gc-transition);
    background: var(--bg-primary, #fff);
}
.gc-ai-input:focus {
    outline: none;
    border-color: var(--gc-tool);
    box-shadow: 0 0 0 3px rgba(139,92,246,0.12), 0 2px 8px rgba(139,92,246,0.06);
    background: #fff;
}
[data-theme="dark"] .gc-ai-input {
    background: var(--gc-input-bg, #0f0d1a);
    border-color: var(--gc-input-border, rgba(139,92,246,0.25));
    color: var(--text-primary, #f1f5f9);
}
[data-theme="dark"] .gc-ai-input:focus {
    border-color: var(--gc-input-border-focus, #a78bfa);
    box-shadow: 0 0 0 3px rgba(167,139,250,0.15), 0 2px 8px rgba(139,92,246,0.1);
    background: #120f22;
}
.gc-ai-chip-row {
    display: flex;
    flex-wrap: wrap;
    gap: 0.25rem;
    margin-top: 0.375rem;
}
.gc-ai-chip {
    padding: 0.2rem 0.625rem;
    font-size: 0.6875rem;
    font-weight: 500;
    color: #6366f1;
    background: rgba(99, 102, 241, 0.06);
    border: 1px solid rgba(99, 102, 241, 0.2);
    border-radius: 2rem;
    cursor: pointer;
    transition: all var(--gc-transition);
}
.gc-ai-chip:hover {
    background: rgba(99, 102, 241, 0.14);
    border-color: rgba(99, 102, 241, 0.4);
    color: #4f46e5;
    transform: translateY(-1px);
    box-shadow: 0 2px 6px rgba(99,102,241,0.12);
}
.gc-ai-chip:active {
    transform: translateY(0) scale(0.97);
}
[data-theme="dark"] .gc-ai-chip {
    color: #a78bfa;
    background: rgba(139, 92, 246, 0.1);
    border-color: rgba(139, 92, 246, 0.25);
}
[data-theme="dark"] .gc-ai-chip:hover {
    background: rgba(139, 92, 246, 0.22);
    border-color: rgba(139, 92, 246, 0.5);
    color: #c4b5fd;
}
.gc-ai-actions {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-top: 0.5rem;
    justify-content: space-between;
    flex-wrap: wrap;
}
.gc-ai-check {
    display: inline-flex;
    align-items: center;
    gap: 0.25rem;
    font-size: 0.6875rem;
    color: var(--text-secondary, #64748b);
    margin: 0;
}
.gc-ai-check input { margin: 0; }
.gc-ai-go {
    padding: 0.5rem 1rem;
    font-size: 0.8125rem;
    font-weight: 600;
    color: #fff;
    background: linear-gradient(135deg, #8b5cf6 0%, #6366f1 50%, #7c3aed 100%);
    border: none;
    border-radius: var(--gc-radius-sm);
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 0.375rem;
    transition: all var(--gc-transition);
    box-shadow: 0 2px 8px rgba(139,92,246,0.25);
    letter-spacing: 0.01em;
}
.gc-ai-go:hover:not(:disabled) {
    box-shadow: 0 4px 16px rgba(139,92,246,0.4);
    transform: translateY(-1px);
}
.gc-ai-go:active:not(:disabled) {
    transform: translateY(0) scale(0.97);
    box-shadow: 0 2px 6px rgba(139,92,246,0.2);
}
.gc-ai-go:disabled { opacity: 0.6; cursor: not-allowed; }
.gc-ai-spinner {
    display: inline-block;
    width: 11px;
    height: 11px;
    border: 2px solid rgba(255, 255, 255, 0.4);
    border-top-color: #fff;
    border-radius: 50%;
    animation: gc-ai-spin 0.8s linear infinite;
}
@keyframes gc-ai-spin { to { transform: rotate(360deg); } }
.gc-ai-status {
    margin-top: 0.5rem;
    padding: 0.5rem 0.625rem;
    font-size: 0.75rem;
    border-radius: 0.375rem;
}
.gc-ai-status.error {
    background: rgba(239, 68, 68, 0.1);
    color: #dc2626;
    border: 1px solid rgba(239, 68, 68, 0.25);
}
.gc-ai-status.info {
    background: rgba(99, 102, 241, 0.08);
    color: #6366f1;
    border: 1px solid rgba(99, 102, 241, 0.2);
}
[data-theme="dark"] .gc-ai-status.error { color: #fca5a5; }
[data-theme="dark"] .gc-ai-status.info { color: #a78bfa; }
.gc-ai-preview {
    margin-top: 0.5rem;
    padding: 0.75rem;
    background: var(--bg-primary, #fff);
    border: 1.5px solid rgba(16, 185, 129, 0.3);
    border-radius: var(--gc-radius-sm);
    box-shadow: 0 2px 8px rgba(16,185,129,0.08);
    animation: gc-ai-preview-in 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}
@keyframes gc-ai-preview-in {
    from { opacity: 0; transform: translateY(4px); }
    to { opacity: 1; transform: translateY(0); }
}
[data-theme="dark"] .gc-ai-preview {
    background: rgba(16,185,129,0.04);
    border-color: rgba(16, 185, 129, 0.3);
    box-shadow: 0 2px 12px rgba(16,185,129,0.1);
}
.gc-ai-preview-title {
    font-size: 0.75rem;
    color: var(--text-secondary, #64748b);
    margin-bottom: 0.375rem;
}
.gc-ai-preview-list {
    list-style: none;
    padding: 0;
    margin: 0;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.75rem;
}
.gc-ai-preview-list li {
    padding: 0.25rem 0;
    border-bottom: 1px dashed var(--border-light, #f1f5f9);
}
.gc-ai-preview-list li:last-child { border-bottom: none; }
.gc-ai-preview-list .gc-ai-type {
    display: inline-block;
    padding: 1px 6px;
    margin-right: 0.375rem;
    font-family: var(--font-sans, sans-serif);
    font-size: 0.625rem;
    font-weight: 600;
    background: rgba(99, 102, 241, 0.15);
    color: #6366f1;
    border-radius: 3px;
}
.gc-ai-preview-list .gc-ai-calc-badge {
    display: inline-block;
    margin-left: 0.375rem;
    padding: 1px 6px;
    font-family: var(--font-sans, sans-serif);
    font-size: 0.625rem;
    font-weight: 600;
    background: rgba(16, 185, 129, 0.15);
    color: #059669;
    border-radius: 3px;
}
[data-theme="dark"] .gc-ai-preview-list .gc-ai-calc-badge {
    background: rgba(16, 185, 129, 0.2);
    color: #34d399;
}
.gc-ai-preview-notes {
    margin-top: 0.375rem;
    font-size: 0.6875rem;
    color: var(--text-muted, #94a3b8);
    font-style: italic;
}
.gc-ai-preview-actions {
    display: flex;
    gap: 0.375rem;
    margin-top: 0.5rem;
}
.gc-ai-confirm {
    padding: 0.375rem 0.875rem;
    font-size: 0.75rem;
    font-weight: 600;
    color: #fff;
    background: linear-gradient(135deg, #10b981, #059669);
    border: none;
    border-radius: var(--gc-radius-xs);
    cursor: pointer;
    transition: all var(--gc-transition);
    box-shadow: 0 2px 6px rgba(16,185,129,0.2);
}
.gc-ai-confirm:hover {
    box-shadow: 0 4px 12px rgba(16,185,129,0.3);
    transform: translateY(-1px);
}
.gc-ai-confirm:active {
    transform: translateY(0) scale(0.97);
}
.gc-ai-cancel {
    padding: 0.375rem 0.875rem;
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-secondary, #64748b);
    background: transparent;
    border: 1px solid var(--border, #e2e8f0);
    border-radius: var(--gc-radius-xs);
    cursor: pointer;
    transition: all var(--gc-transition);
}
.gc-ai-cancel:hover {
    background: var(--bg-hover, #f8fafc);
    border-color: var(--border-dark, #cbd5e1);
}
.gc-ai-panel {
    margin-top: 0.5rem;
    background: rgba(99, 102, 241, 0.03);
    border: 1px solid rgba(99, 102, 241, 0.2);
    animation: gc-ai-preview-in 0.25s cubic-bezier(0.16, 1, 0.3, 1);
    border-radius: 0.5rem;
    overflow: hidden;
}
.gc-ai-panel-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.375rem 0.625rem;
    background: rgba(99, 102, 241, 0.08);
    border-bottom: 1px solid rgba(99, 102, 241, 0.2);
    font-size: 0.75rem;
    font-weight: 600;
    color: #6366f1;
}
.gc-ai-panel-close {
    background: transparent;
    border: none;
    color: var(--text-muted, #94a3b8);
    font-size: 1.125rem;
    line-height: 1;
    cursor: pointer;
    padding: 0 0.25rem;
}
.gc-ai-panel-close:hover { color: #ef4444; }
.gc-ai-panel-body {
    padding: 0.625rem 0.75rem;
    font-size: 0.8125rem;
    line-height: 1.55;
    color: var(--text-primary, #0f172a);
    max-height: 280px;
    overflow-y: auto;
    white-space: pre-wrap;
    word-break: break-word;
}
[data-theme="dark"] .gc-ai-panel-body { color: var(--text-primary, #f1f5f9); }
.gc-ai-panel-body code {
    background: rgba(0,0,0,0.07);
    padding: 1px 5px;
    border-radius: 3px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.85em;
}
[data-theme="dark"] .gc-ai-panel-body code { background: rgba(255,255,255,0.1); }
.gc-ai-explain-hint {
    font-size: 0.6875rem;
    color: var(--text-muted, #94a3b8);
    margin: 0 0 0.375rem 0;
    line-height: 1.4;
}
.gc-ai-firewall {
    margin: 0.5rem 0 0 0;
    font-size: 0.625rem;
    color: var(--text-muted, #94a3b8);
    font-style: italic;
    line-height: 1.3;
}

/* ========================================
   Premium Dark Mode: layered surfaces
   Following Modern Dark Cinema / glassmorphism
   ======================================== */
[data-theme="dark"] .gc-page-container .tool-card {
    background: #0f0d1a;
    border-color: rgba(255,255,255,0.06);
    box-shadow: var(--gc-shadow-card);
}
[data-theme="dark"] .gc-page-container .tool-card-header {
    background: linear-gradient(135deg, rgba(139,92,246,0.3) 0%, rgba(99,102,241,0.2) 100%);
    border-bottom-color: rgba(255,255,255,0.06);
}
[data-theme="dark"] .gc-page-container .tool-card-body {
    background: transparent;
}
[data-theme="dark"] .gc-page-container .expression-item {
    background: rgba(255,255,255,0.03);
    border: 1px solid rgba(255,255,255,0.06);
}
[data-theme="dark"] .gc-page-container .expression-item:hover {
    background: rgba(255,255,255,0.05);
    border-color: rgba(139,92,246,0.2);
}
[data-theme="dark"] .gc-page-container .expression-item:focus-within {
    border-color: rgba(139,92,246,0.35);
    box-shadow: 0 0 0 1px rgba(139,92,246,0.15), 0 4px 12px rgba(139,92,246,0.1);
}
[data-theme="dark"] .gc-graph-card {
    background: #0a0812;
    border-color: rgba(255,255,255,0.06);
}
[data-theme="dark"] .gc-graph-toolbar {
    background: rgba(15,13,26,0.9);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-color: rgba(255,255,255,0.06);
}
[data-theme="dark"] .gc-preset-chip {
    background: rgba(255,255,255,0.04);
    border-color: rgba(255,255,255,0.1);
    color: var(--text-secondary, #94a3b8);
}
[data-theme="dark"] .gc-preset-chip:hover {
    background: rgba(139,92,246,0.15);
    border-color: rgba(139,92,246,0.4);
    color: #c4b5fd;
    box-shadow: 0 2px 8px rgba(139,92,246,0.2);
}
[data-theme="dark"] .gc-btn-add {
    box-shadow: 0 2px 8px rgba(139,92,246,0.3);
}
[data-theme="dark"] .gc-btn-add:hover {
    box-shadow: 0 4px 16px rgba(139,92,246,0.4);
}
[data-theme="dark"] .gc-sidebar-actions .gc-action-btn {
    background: rgba(255,255,255,0.04);
    border-color: rgba(255,255,255,0.08);
    color: var(--text-secondary, #cbd5e1);
}
[data-theme="dark"] .gc-sidebar-actions .gc-action-btn:hover {
    background: rgba(139,92,246,0.12);
    border-color: rgba(139,92,246,0.3);
    color: #c4b5fd;
}
[data-theme="dark"] .gc-page-container .tool-section-header {
    border-color: rgba(255,255,255,0.06);
    color: #cbd5e1;
}
[data-theme="dark"] .gc-page-container .tool-section-content {
    border-color: rgba(255,255,255,0.04);
}
/* AI card dark mode elevation */
[data-theme="dark"] .gc-ai-card .gc-ai-header {
    background: linear-gradient(135deg, rgba(139,92,246,0.4) 0%, rgba(99,102,241,0.3) 50%, rgba(124,58,237,0.35) 100%);
}
[data-theme="dark"] .gc-ai-go {
    box-shadow: 0 2px 12px rgba(139,92,246,0.35);
}
[data-theme="dark"] .gc-ai-go:hover:not(:disabled) {
    box-shadow: 0 4px 20px rgba(139,92,246,0.5);
}
[data-theme="dark"] .gc-ai-confirm {
    box-shadow: 0 2px 8px rgba(16,185,129,0.25);
}
/* Smooth focus ring on all interactive elements */
.gc-page-container :focus-visible {
    outline: 2px solid var(--gc-tool);
    outline-offset: 2px;
    border-radius: 2px;
}
/* Reduced motion: disable all transforms and animations */
@media (prefers-reduced-motion: reduce) {
    .gc-page-container *,
    .gc-page-container *::before,
    .gc-page-container *::after {
        animation-duration: 0.01ms !important;
        transition-duration: 0.01ms !important;
    }
}