/**
 * ODE Solver Calculator - page-specific styles
 * Loaded by ode-solver-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: #db2777;
    --tool-primary-dark: #be185d;
    --tool-gradient: linear-gradient(135deg, #db2777 0%, #f472b6 100%);
    --tool-light: #fdf2f8;
}
[data-theme="dark"] {
    --tool-light: rgba(219, 39, 119, 0.15);
}

/* ===== Mode toggle (3 buttons: First-Order | Second-Order | Direction Field) ===== */
.ode-mode-toggle {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    border: 1.5px solid var(--border, #e2e8f0);
    border-radius: var(--radius-md, 0.5rem);
    overflow: hidden;
    margin-bottom: 0.875rem;
}
.ode-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;
}
.ode-mode-btn.active {
    background: var(--tool-gradient);
    color: #fff;
}
.ode-mode-btn:hover:not(.active) {
    background: var(--bg-tertiary);
}
[data-theme="dark"] .ode-mode-btn { background: var(--bg-tertiary); }
[data-theme="dark"] .ode-mode-btn.active { background: var(--tool-gradient); color: #fff; }
[data-theme="dark"] .ode-mode-btn:hover:not(.active) { background: rgba(255, 255, 255, 0.08); }

/* ===== Live preview ===== */
.ode-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;
}
.ode-preview .katex-display { margin: 0; }
[data-theme="dark"] .ode-preview {
    background: var(--bg-tertiary);
    border-color: var(--border);
}

/* ===== Quick examples ===== */
.ode-examples {
    display: flex;
    flex-wrap: wrap;
    gap: 0.375rem;
}
.ode-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;
}
.ode-example-chip:hover {
    background: var(--tool-primary);
    color: #fff;
    border-color: var(--tool-primary);
}
[data-theme="dark"] .ode-example-chip {
    background: var(--bg-tertiary);
    border-color: var(--border);
    color: var(--text-secondary);
}
[data-theme="dark"] .ode-example-chip:hover {
    background: var(--tool-primary);
    color: #fff;
}

/* ===== Reference Table ===== */
.ode-formulas-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);
}
.ode-formulas-content {
    display: none;
    padding-bottom: 0.5rem;
}
.ode-formulas-content.open { display: block; }
.ode-formulas-chevron {
    transition: transform 0.2s;
    width: 14px;
    height: 14px;
    flex-shrink: 0;
}
.ode-formulas-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.8125rem;
    margin-top: 0.5rem;
}
.ode-formulas-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;
}
.ode-formulas-table td {
    padding: 0.4375rem 0.625rem;
    border-bottom: 1px solid var(--border-light, #f1f5f9);
    color: var(--text-secondary);
    vertical-align: middle;
}
.ode-formulas-table tr:last-child td { border-bottom: none; }
[data-theme="dark"] .ode-formulas-table th { background: var(--tool-light); }
[data-theme="dark"] .ode-formulas-table td { border-bottom-color: var(--border); }

/* ===== Syntax help ===== */
.ode-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);
}
.ode-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;
}
.ode-syntax-content.open { display: block; }
.ode-syntax-chevron {
    transition: transform 0.2s;
    width: 14px;
    height: 14px;
    flex-shrink: 0;
}

/* ===== Output tabs ===== */
.ode-output-tabs {
    display: flex;
    border: 1.5px solid var(--border, #e2e8f0);
    border-radius: var(--radius-md, 0.5rem);
    overflow: hidden;
}
.ode-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;
}
.ode-output-tab.active {
    background: var(--tool-gradient);
    color: #fff;
}
.ode-output-tab:hover:not(.active) {
    background: var(--bg-tertiary);
}
[data-theme="dark"] .ode-output-tab { background: var(--bg-tertiary); }
[data-theme="dark"] .ode-output-tab.active { background: var(--tool-gradient); color: #fff; }
[data-theme="dark"] .ode-output-tab:hover:not(.active) { background: rgba(255, 255, 255, 0.08); }

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

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

/* ===== Result detail ===== */
.ode-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);
    overflow-x: auto;
    display: flex;
    flex-wrap: wrap;
    gap: 0.375rem;
    align-items: center;
}
[data-theme="dark"] .ode-result-detail {
    background: var(--bg-tertiary);
    border-color: var(--border);
}

/* ===== Method badge ===== */
.ode-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;
}

/* ===== Classification badge ===== */
.ode-classify-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;
    margin-left: 0.375rem;
}

/* ===== Verified badge ===== */
.ode-verified-badge {
    display: inline-block;
    background: #dcfce7;
    color: #16a34a;
    padding: 0.2rem 0.625rem;
    border-radius: 9999px;
    font-size: 0.6875rem;
    font-weight: 600;
    margin-left: 0.375rem;
}
[data-theme="dark"] .ode-verified-badge {
    background: rgba(22, 163, 74, 0.15);
    color: #4ade80;
}

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

/* ===== Steps ===== */
.ode-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;
}
.ode-steps-btn:hover {
    background: var(--tool-primary);
    color: #fff;
}
.ode-steps-container {
    margin-top: 1rem;
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    overflow: hidden;
    min-width: 0;
}
.ode-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);
}
.ode-step {
    padding: 0.75rem 1rem;
    border-bottom: 1px solid var(--border-light);
    display: flex;
    gap: 0.75rem;
    align-items: flex-start;
}
.ode-step:last-child { border-bottom: none; }
.ode-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;
}
.ode-step-body { flex: 1; min-width: 0; }
.ode-step-title {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 0.25rem;
}
.ode-step-math {
    font-size: 1rem;
    overflow-x: auto;
    overflow-y: hidden;
}
.ode-step-math .katex-display {
    margin: 0;
    overflow-x: auto;
    overflow-y: hidden;
    white-space: nowrap;
    display: inline-block;
    min-width: min-content;
}
.ode-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"] .ode-steps-container { border-color: var(--border); }
[data-theme="dark"] .ode-steps-header { background: var(--tool-light); border-bottom-color: var(--border); }
[data-theme="dark"] .ode-step { border-bottom-color: var(--border); }

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

/* ===== Action row (Compute + Random) ===== */
.ode-action-row {
    display: flex;
    gap: 0.5rem;
    margin-top: 1rem;
}
.ode-action-row .ode-compute-btn {
    flex: 1;
    margin-top: 0;
}
.ode-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;
}
.ode-random-btn:hover {
    background: var(--tool-primary);
    color: #fff;
}
.ode-random-btn:active {
    transform: scale(0.96);
}
[data-theme="dark"] .ode-random-btn {
    background: var(--bg-tertiary);
    border-color: var(--tool-primary);
    color: #f9a8d4;
}
[data-theme="dark"] .ode-random-btn:hover {
    background: var(--tool-primary);
    color: #fff;
}

/* ===== IC checkbox row ===== */
.ode-ic-row {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-top: 0.5rem;
    font-size: 0.8125rem;
    color: var(--text-secondary);
}
.ode-ic-row input[type="checkbox"] {
    accent-color: var(--tool-primary);
}
.ode-ic-fields {
    display: none;
    gap: 0.5rem;
    margin-top: 0.5rem;
}
.ode-ic-fields.open {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
}

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

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

/* ===== Order selector (Higher-Order sub-buttons) ===== */
.ode-order-selector {
    display: inline-flex;
    gap: 0.375rem;
    margin-bottom: 0.75rem;
}
.ode-order-btn {
    padding: 0.3rem 0.75rem;
    font-size: 0.75rem;
    font-weight: 600;
    font-family: var(--font-sans);
    border: 1.5px solid var(--border, #e2e8f0);
    border-radius: 9999px;
    background: var(--bg-secondary);
    color: var(--text-secondary);
    cursor: pointer;
    transition: all 0.15s;
}
.ode-order-btn.active {
    background: var(--tool-primary);
    color: #fff;
    border-color: var(--tool-primary);
}
.ode-order-btn:hover:not(.active) {
    background: var(--bg-tertiary);
    border-color: var(--tool-primary);
    color: var(--tool-primary);
}
[data-theme="dark"] .ode-order-btn {
    background: var(--bg-tertiary);
    border-color: var(--border);
}
[data-theme="dark"] .ode-order-btn.active {
    background: var(--tool-primary);
    color: #fff;
    border-color: var(--tool-primary);
}
[data-theme="dark"] .ode-order-btn:hover:not(.active) {
    background: rgba(255, 255, 255, 0.08);
    border-color: var(--tool-primary);
    color: #f9a8d4;
}

/* ===== Scrollable result containment ===== */
.ode-result-scroll-hint {
    text-align: center;
    font-size: 0.6875rem;
    color: var(--text-muted);
    padding: 0.25rem 0 0;
    opacity: 0.7;
}

/* ===== Extra IC fields (dynamic) ===== */
#ode-extra-ic-fields {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
    gap: 0.5rem;
}
#ode-extra-ic-fields:empty {
    display: none;
}

/* ===== Mobile responsive for order selector ===== */
@media (max-width: 480px) {
    .ode-order-selector {
        flex-wrap: wrap;
    }
    .ode-order-btn {
        padding: 0.25rem 0.625rem;
        font-size: 0.6875rem;
    }
}