/**
 * Z-Transform Calculator - page-specific styles
 * Loaded by z-transform-calculator.jsp
 * Shared styles (nav, grid, cards, form, result, empty state) come from
 * design-system.css, navigation.css, three-column-tool.css
 */

/* ===== Tool color tokens ===== */
:root {
    --tool-primary: #059669;
    --tool-primary-dark: #047857;
    --tool-gradient: linear-gradient(135deg, #059669 0%, #10b981 100%);
    --tool-light: #ecfdf5;
}
[data-theme="dark"] {
    --tool-light: rgba(5, 150, 105, 0.15);
}

/* ===== Mode toggle (2 buttons: Forward | Inverse) ===== */
.zt-mode-toggle {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    border: 1.5px solid var(--border, #e2e8f0);
    border-radius: var(--radius-md, 0.5rem);
    overflow: hidden;
    margin-bottom: 0.875rem;
}
.zt-mode-btn {
    padding: 0.5rem;
    font-weight: 600;
    font-size: 0.8125rem;
    border: none;
    cursor: pointer;
    background: var(--bg-secondary);
    color: var(--text-secondary);
    transition: all 0.15s;
    font-family: var(--font-sans);
    text-align: center;
}
.zt-mode-btn.active {
    background: var(--tool-gradient);
    color: #fff;
}
.zt-mode-btn:hover:not(.active) {
    background: var(--bg-tertiary);
}
[data-theme="dark"] .zt-mode-btn { background: var(--bg-tertiary); }
[data-theme="dark"] .zt-mode-btn.active { background: var(--tool-gradient); color: #fff; }
[data-theme="dark"] .zt-mode-btn:hover:not(.active) { background: rgba(255, 255, 255, 0.08); }

/* ===== Live preview ===== */
.zt-preview {
    background: var(--bg-secondary, #f8fafc);
    border: 1px solid var(--border, #e2e8f0);
    border-radius: var(--radius-md, 0.5rem);
    padding: 0.75rem 1rem;
    min-height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow-x: auto;
    font-size: 1.1rem;
}
.zt-preview .katex-display { margin: 0; }
[data-theme="dark"] .zt-preview {
    background: var(--bg-tertiary);
    border-color: var(--border);
}

/* ===== Quick examples ===== */
.zt-examples {
    display: flex;
    flex-wrap: wrap;
    gap: 0.375rem;
}
.zt-example-chip {
    padding: 0.3rem 0.625rem;
    font-size: 0.75rem;
    font-family: var(--font-mono);
    background: var(--bg-secondary, #f8fafc);
    border: 1px solid var(--border, #e2e8f0);
    border-radius: var(--radius-full, 9999px);
    cursor: pointer;
    transition: all 0.15s;
    color: var(--text-secondary);
    white-space: nowrap;
}
.zt-example-chip:hover {
    background: var(--tool-primary);
    color: #fff;
    border-color: var(--tool-primary);
}
[data-theme="dark"] .zt-example-chip {
    background: var(--bg-tertiary);
    border-color: var(--border);
    color: var(--text-secondary);
}
[data-theme="dark"] .zt-example-chip:hover {
    background: var(--tool-primary);
    color: #fff;
}

/* ===== Z-Transform Pairs Table ===== */
.zt-pairs-toggle {
    display: flex;
    align-items: center;
    justify-content: space-between;
    cursor: pointer;
    padding: 0.5rem 0;
    font-size: 0.8125rem;
    font-weight: 600;
    color: var(--text-secondary);
    border: none;
    background: none;
    width: 100%;
    font-family: var(--font-sans);
}
.zt-pairs-content {
    display: none;
    padding-bottom: 0.5rem;
}
.zt-pairs-content.open { display: block; }
.zt-pairs-chevron {
    transition: transform 0.2s;
    width: 14px;
    height: 14px;
    flex-shrink: 0;
}
.zt-pairs-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.8125rem;
    margin-top: 0.5rem;
}
.zt-pairs-table th {
    background: var(--tool-light);
    color: var(--tool-primary);
    font-weight: 600;
    padding: 0.5rem 0.625rem;
    text-align: left;
    border-bottom: 1.5px solid var(--border);
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.03em;
}
.zt-pairs-table td {
    padding: 0.4375rem 0.625rem;
    border-bottom: 1px solid var(--border-light, #f1f5f9);
    color: var(--text-secondary);
    vertical-align: middle;
}
.zt-pairs-table tr:last-child td { border-bottom: none; }
[data-theme="dark"] .zt-pairs-table th { background: var(--tool-light); }
[data-theme="dark"] .zt-pairs-table td { border-bottom-color: var(--border); }

/* ===== Syntax help ===== */
.zt-syntax-toggle {
    display: flex;
    align-items: center;
    justify-content: space-between;
    cursor: pointer;
    padding: 0.5rem 0;
    font-size: 0.8125rem;
    font-weight: 600;
    color: var(--text-secondary);
    border: none;
    background: none;
    width: 100%;
    font-family: var(--font-sans);
}
.zt-syntax-content {
    display: none;
    font-size: 0.75rem;
    font-family: var(--font-mono);
    color: var(--text-secondary);
    line-height: 1.8;
    padding-bottom: 0.5rem;
}
.zt-syntax-content.open { display: block; }
.zt-syntax-chevron {
    transition: transform 0.2s;
    width: 14px;
    height: 14px;
    flex-shrink: 0;
}

/* ===== Output tabs ===== */
.zt-output-tabs {
    display: flex;
    border: 1.5px solid var(--border, #e2e8f0);
    border-radius: var(--radius-md, 0.5rem);
    overflow: hidden;
}
.zt-output-tab {
    flex: 1;
    padding: 0.5rem;
    font-weight: 600;
    font-size: 0.8125rem;
    border: none;
    cursor: pointer;
    background: var(--bg-secondary);
    color: var(--text-secondary);
    transition: all 0.15s;
    font-family: var(--font-sans);
    text-align: center;
}
.zt-output-tab.active {
    background: var(--tool-gradient);
    color: #fff;
}
.zt-output-tab:hover:not(.active) {
    background: var(--bg-tertiary);
}
[data-theme="dark"] .zt-output-tab { background: var(--bg-tertiary); }
[data-theme="dark"] .zt-output-tab.active { background: var(--tool-gradient); color: #fff; }
[data-theme="dark"] .zt-output-tab:hover:not(.active) { background: rgba(255, 255, 255, 0.08); }

/* ===== Panels ===== */
.zt-panel { display: none; flex: 1; min-height: 0; }
.zt-panel.active { display: flex; flex-direction: column; }
#zt-panel-result .tool-result-card { flex: 1; }

/* ===== Result display ===== */
.zt-result-math {
    padding: 1.5rem;
    overflow-x: auto;
    max-width: 100%;
    text-align: center;
}
.zt-result-math .katex-display {
    margin: 0.5rem 0;
    overflow-x: auto;
    overflow-y: hidden;
}
.zt-result-label {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted);
    margin-bottom: 0.25rem;
}
.zt-result-main {
    font-size: 1.3rem;
    padding: 1rem 0;
}

/* ===== Convergence badge ===== */
.zt-convergence-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.375rem;
    padding: 0.3rem 0.75rem;
    background: var(--tool-light);
    color: var(--tool-primary);
    border-radius: 9999px;
    font-size: 0.75rem;
    font-weight: 600;
    margin-top: 0.5rem;
}

/* ===== Result detail ===== */
.zt-result-detail {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    padding: 0.75rem 1rem;
    margin-top: 0.75rem;
    font-size: 0.8125rem;
    color: var(--text-secondary);
}
[data-theme="dark"] .zt-result-detail {
    background: var(--bg-tertiary);
    border-color: var(--border);
}

/* ===== Method badge ===== */
.zt-method-badge {
    display: inline-block;
    background: var(--tool-light);
    color: var(--tool-primary);
    padding: 0.2rem 0.625rem;
    border-radius: 9999px;
    font-size: 0.6875rem;
    font-weight: 600;
}

/* ===== Error state ===== */
.zt-error {
    background: #fef3c7;
    border: 1px solid #fbbf24;
    border-radius: var(--radius-md);
    padding: 1.25rem;
    color: #92400e;
}
.zt-error h4 {
    margin: 0 0 0.5rem;
    font-size: 0.9375rem;
    font-weight: 700;
}
.zt-error ul {
    margin: 0.5rem 0 0;
    padding-left: 1.25rem;
    font-size: 0.8125rem;
    line-height: 1.7;
}
[data-theme="dark"] .zt-error {
    background: rgba(251, 191, 36, 0.15);
    border-color: rgba(251, 191, 36, 0.3);
    color: #fbbf24;
}

/* ===== Steps ===== */
.zt-steps-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.375rem;
    padding: 0.5rem 1rem;
    font-size: 0.8125rem;
    font-weight: 600;
    font-family: var(--font-sans);
    border: 1.5px solid var(--tool-primary);
    border-radius: var(--radius-full);
    background: transparent;
    color: var(--tool-primary);
    cursor: pointer;
    transition: all 0.15s;
    margin-top: 0.75rem;
}
.zt-steps-btn:hover {
    background: var(--tool-primary);
    color: #fff;
}
.zt-steps-container {
    margin-top: 1rem;
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    overflow: hidden;
}
.zt-steps-header {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.625rem 1rem;
    background: var(--tool-light);
    border-bottom: 1px solid var(--border);
    font-size: 0.8125rem;
    font-weight: 600;
    color: var(--tool-primary);
}
.zt-step {
    padding: 0.75rem 1rem;
    border-bottom: 1px solid var(--border-light);
    display: flex;
    gap: 0.75rem;
    align-items: flex-start;
}
.zt-step:last-child { border-bottom: none; }
.zt-step-num {
    flex-shrink: 0;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: var(--tool-gradient);
    color: #fff;
    font-size: 0.6875rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    justify-content: center;
}
.zt-step-body { flex: 1; min-width: 0; }
.zt-step-title {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 0.25rem;
}
.zt-step-math {
    font-size: 1rem;
    overflow-x: auto;
    overflow-y: hidden;
}
.zt-step-math .katex-display {
    margin: 0;
    overflow-x: auto;
    overflow-y: hidden;
    white-space: nowrap;
    display: inline-block;
    min-width: min-content;
}
.zt-steps-sympy-badge {
    font-size: 0.625rem;
    font-weight: 500;
    padding: 0.125rem 0.5rem;
    border-radius: 9999px;
    background: var(--bg-secondary);
    color: var(--text-muted);
    margin-left: auto;
}
[data-theme="dark"] .zt-steps-container { border-color: var(--border); }
[data-theme="dark"] .zt-steps-header { background: var(--tool-light); border-bottom-color: var(--border); }
[data-theme="dark"] .zt-step { border-bottom-color: var(--border); }

/* ===== Graph ===== */
#zt-graph-container {
    width: 100%;
    min-height: 440px;
    border-radius: var(--radius-md);
}
#zt-panel-graph { min-height: 480px; }
#zt-panel-python { min-height: 540px; }
#zt-panel-result .tool-result-card { flex: 1; }

/* ===== Action row (Compute + Random) ===== */
.zt-action-row {
    display: flex;
    gap: 0.5rem;
    margin-top: 1rem;
}
.zt-action-row .zt-compute-btn {
    flex: 1;
    margin-top: 0;
}
.zt-random-btn {
    flex: 0 0 auto;
    padding: 0.75rem 1rem;
    font-weight: 600;
    font-size: 0.8125rem;
    font-family: var(--font-sans);
    border: 1.5px solid var(--tool-primary);
    border-radius: var(--radius-md, 0.5rem);
    background: var(--bg-primary);
    color: var(--tool-primary);
    cursor: pointer;
    transition: all 0.15s;
    display: inline-flex;
    align-items: center;
    gap: 0.375rem;
}
.zt-random-btn:hover {
    background: var(--tool-primary);
    color: #fff;
}
.zt-random-btn:active {
    transform: scale(0.96);
}
[data-theme="dark"] .zt-random-btn {
    background: var(--bg-tertiary);
    border-color: var(--tool-primary);
    color: #34d399;
}
[data-theme="dark"] .zt-random-btn:hover {
    background: var(--tool-primary);
    color: #fff;
}

/* ===== Separator ===== */
.zt-sep {
    border: none;
    border-top: 1px solid var(--border, #e2e8f0);
    margin: 0.75rem 0;
}

/* ===== Spinner ===== */
@keyframes zt-spin {
    to { transform: rotate(360deg); }
}
.zt-spinner {
    width: 14px;
    height: 14px;
    border: 2px solid var(--border);
    border-top-color: var(--tool-primary);
    border-radius: 50%;
    animation: zt-spin 0.6s linear infinite;
}

/* ===== AI Describe Section ===== */
.zt-ai-group {
    margin-bottom: 0.75rem;
    padding: 0.75rem;
    background: linear-gradient(135deg, rgba(99,102,241,0.06), rgba(139,92,246,0.04));
    border: 1px solid rgba(99,102,241,0.15);
    border-radius: 0.5rem;
}
.zt-ai-label { color: #6366f1 !important; font-weight: 600 !important; }
.zt-ai-row { display: flex; gap: 0.4rem; margin-top: 0.4rem; }
.zt-ai-row .tool-input { flex: 1; font-size: 0.85rem; }
.zt-ai-btn {
    padding: 0.45rem 0.9rem;
    background: linear-gradient(135deg, #6366f1, #8b5cf6);
    color: #fff; border: none; border-radius: 0.375rem;
    font-size: 0.8rem; font-weight: 600; cursor: pointer;
    white-space: nowrap; transition: transform 0.12s, box-shadow 0.12s;
}
.zt-ai-btn:hover { transform: translateY(-1px); box-shadow: 0 3px 10px rgba(99,102,241,0.3); }
.zt-ai-btn:disabled { opacity: 0.6; cursor: wait; transform: none; box-shadow: none; }
.zt-ai-status { margin-top: 0.4rem; padding: 0.35rem 0.5rem; border-radius: 0.25rem; font-size: 0.78rem; }
.zt-ai-status.loading { color: #6366f1; background: rgba(99,102,241,0.08); }
.zt-ai-status.success { color: #16a34a; background: rgba(22,163,74,0.08); }
.zt-ai-status.error { color: #dc2626; background: rgba(220,38,38,0.08); }
.zt-ai-examples { display: flex; flex-wrap: wrap; gap: 0.3rem; margin-top: 0.5rem; }
.zt-ai-chip {
    padding: 0.2rem 0.5rem; background: rgba(99,102,241,0.08);
    border: 1px solid rgba(99,102,241,0.15); border-radius: 12px;
    font-size: 0.7rem; color: #6366f1; font-weight: 500; cursor: pointer;
    transition: background 0.12s;
}
.zt-ai-chip:hover { background: rgba(99,102,241,0.15); }
[data-theme="dark"] .zt-ai-group { background: linear-gradient(135deg, rgba(99,102,241,0.08), rgba(139,92,246,0.05)); border-color: rgba(99,102,241,0.2); }
[data-theme="dark"] .zt-ai-label { color: #818cf8 !important; }
[data-theme="dark"] .zt-ai-chip { background: rgba(99,102,241,0.12); border-color: rgba(99,102,241,0.2); color: #a5b4fc; }
[data-theme="dark"] .zt-ai-chip:hover { background: rgba(99,102,241,0.2); }