/* System font stack for performance */
:root {
    --font-sans: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    --font-mono: ui-monospace, "Cascadia Code", "Source Code Pro", Menlo, Consolas, monospace;

    /* Colors - accessible contrast ratios */
    --color-bg: #fafafa;
    --color-surface: #ffffff;
    --color-text: #1a1a2e;
    --color-text-muted: #555555;
    --color-primary: #0066cc;
    --color-primary-hover: #0052a3;
    --color-success: #0a7c42;
    --color-warning: #b45309;
    --color-error: #c41e3a;
    --color-border: #e0e0e0;

    /* Spacing */
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-2xl: 3rem;

    /* Touch target minimum */
    --touch-target: 48px;
}

/* Dark mode */
@media (prefers-color-scheme: dark) {
    :root {
        --color-bg: #1a1a2e;
        --color-surface: #242438;
        --color-text: #f0f0f0;
        --color-text-muted: #a0a0a0;
        --color-primary: #4d9fff;
        --color-primary-hover: #6eb0ff;
        --color-border: #3a3a4e;
    }
}

/* Reset */
*, *::before, *::after {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: var(--font-sans);
    font-size: 1rem;
    line-height: 1.6;
    color: var(--color-text);
    background-color: var(--color-bg);
}

/* Skip link for accessibility */
.skip-link {
    position: absolute;
    top: -100%;
    left: 0;
    padding: var(--space-sm) var(--space-md);
    background: var(--color-primary);
    color: white;
    z-index: 1000;
    text-decoration: none;
}

.skip-link:focus {
    top: 0;
}

/* Visually hidden (screen reader only) */
.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* Header */
header {
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    padding: var(--space-md) var(--space-lg);
}

header nav {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: var(--space-md);
}

.logo {
    font-size: 1.25rem;
    color: var(--color-text);
    text-decoration: none;
}

header ul {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    gap: var(--space-lg);
}

header a {
    color: var(--color-text);
    text-decoration: none;
    padding: var(--space-sm) var(--space-md);
    min-height: var(--touch-target);
    display: inline-flex;
    align-items: center;
    border-radius: 4px;
}

header a:hover,
header a:focus {
    background: var(--color-bg);
}

header a[aria-current="page"] {
    font-weight: 600;
    color: var(--color-primary);
}

/* Info button in header */
.btn-info {
    display: inline-flex;
    align-items: center;
    gap: var(--space-xs);
    padding: var(--space-sm) var(--space-md);
    min-height: var(--touch-target);
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-text);
    background: transparent;
    border: 1px solid var(--color-border);
    border-radius: 6px;
    cursor: pointer;
    transition: background-color 0.15s, border-color 0.15s;
}

.btn-info:hover,
.btn-info:focus {
    background: var(--color-bg);
    border-color: var(--color-primary);
}

.btn-info-label {
    display: none;
}

@media (min-width: 600px) {
    .btn-info-label {
        display: inline;
    }
}

/* Info Panel Backdrop */
.info-panel-backdrop {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    z-index: 100;
    opacity: 0;
    visibility: hidden;
    transition: opacity 200ms ease-out, visibility 200ms;
}

.info-panel-backdrop[aria-hidden="false"] {
    opacity: 1;
    visibility: visible;
}

/* Info Panel */
.info-panel {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    width: min(420px, 100vw);
    background: var(--color-surface);
    box-shadow: -4px 0 24px rgba(0, 0, 0, 0.15);
    z-index: 101;
    transform: translateX(100%);
    transition: transform 200ms ease-out;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.info-panel[aria-hidden="false"] {
    transform: translateX(0);
}

.info-panel-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-lg);
    border-bottom: 1px solid var(--color-border);
    flex-shrink: 0;
}

.info-panel-header h2 {
    margin: 0;
    font-size: 1.25rem;
}

.info-panel-close {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    font-size: 1.5rem;
    color: var(--color-text-muted);
    background: transparent;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    transition: background-color 0.15s, color 0.15s;
}

.info-panel-close:hover,
.info-panel-close:focus {
    background: var(--color-bg);
    color: var(--color-text);
}

.info-panel-content {
    flex: 1;
    overflow-y: auto;
    padding: var(--space-lg);
}

.info-intro {
    margin: 0 0 var(--space-xl);
    color: var(--color-text-muted);
    line-height: 1.7;
}

/* Algorithm Cards */
.algo-card {
    background: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: 8px;
    padding: var(--space-lg);
    margin-bottom: var(--space-md);
}

.algo-card-primary {
    border-color: var(--color-primary);
    border-width: 2px;
}

.algo-title {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    margin: 0 0 var(--space-sm);
    font-size: 1rem;
}

.algo-icon {
    font-size: 1.25rem;
}

.algo-summary {
    margin: 0 0 var(--space-md);
    color: var(--color-text-muted);
    font-size: 0.9375rem;
    line-height: 1.6;
}

.algo-details {
    border-top: 1px solid var(--color-border);
    padding-top: var(--space-md);
    margin-top: var(--space-md);
}

.algo-details summary {
    cursor: pointer;
    font-weight: 500;
    color: var(--color-primary);
    padding: var(--space-xs) 0;
    min-height: var(--touch-target);
    display: flex;
    align-items: center;
}

.algo-details summary:hover {
    text-decoration: underline;
}

.algo-details[open] summary {
    margin-bottom: var(--space-md);
}

.algo-technical {
    font-size: 0.875rem;
    line-height: 1.6;
}

.algo-technical p {
    margin: 0 0 var(--space-sm);
}

.algo-technical code {
    background: var(--color-surface);
    padding: var(--space-xs) var(--space-sm);
    border-radius: 4px;
    font-family: var(--font-mono);
    font-size: 0.8125rem;
}

.synonym-list {
    margin: var(--space-xs) 0 var(--space-md);
    padding-left: var(--space-lg);
}

.synonym-list li {
    font-family: var(--font-mono);
    font-size: 0.8125rem;
    color: var(--color-text-muted);
    margin-bottom: var(--space-xs);
}

/* Body scroll lock when panel is open */
body.panel-open {
    overflow: hidden;
}

/* Main content */
main {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--space-xl) var(--space-lg);
}

/* Footer */
footer {
    text-align: center;
    padding: var(--space-xl) var(--space-lg);
    color: var(--color-text-muted);
    border-top: 1px solid var(--color-border);
    margin-top: var(--space-2xl);
}

footer a {
    color: var(--color-primary);
}

/* Hero section */
.hero {
    text-align: center;
    padding: var(--space-2xl) 0;
}

.hero h1 {
    font-size: clamp(1.75rem, 4vw, 2.5rem);
    margin: 0 0 var(--space-md);
}

.lead {
    font-size: 1.125rem;
    color: var(--color-text-muted);
    max-width: 600px;
    margin: 0 auto var(--space-xl);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: var(--touch-target);
    min-width: var(--touch-target);
    padding: var(--space-sm) var(--space-lg);
    font-size: 1rem;
    font-weight: 500;
    text-decoration: none;
    border: 2px solid transparent;
    border-radius: 6px;
    cursor: pointer;
    transition: background-color 0.15s, border-color 0.15s;
}

.btn-primary {
    background: var(--color-primary);
    color: white;
}

.btn-primary:hover,
.btn-primary:focus {
    background: var(--color-primary-hover);
}

.btn-secondary {
    background: transparent;
    color: var(--color-primary);
    border-color: var(--color-primary);
}

.btn-secondary:hover,
.btn-secondary:focus {
    background: var(--color-primary);
    color: white;
}

/* Focus styles */
:focus {
    outline: 3px solid var(--color-primary);
    outline-offset: 2px;
}

:focus:not(:focus-visible) {
    outline: none;
}

:focus-visible {
    outline: 3px solid var(--color-primary);
    outline-offset: 2px;
}

/* Features */
.features, .performance, .examples {
    margin-top: var(--space-2xl);
}

.features h2, .performance h2, .examples h2 {
    text-align: center;
    margin-bottom: var(--space-xl);
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--space-lg);
    padding: 0;
    margin: 0;
}

.feature-card {
    background: var(--color-surface);
    padding: var(--space-lg);
    border-radius: 8px;
    border: 1px solid var(--color-border);
}

.feature-card h3 {
    margin: 0 0 var(--space-sm);
    color: var(--color-primary);
}

.feature-card p {
    margin: 0;
    color: var(--color-text-muted);
}

/* Stats */
.stats {
    display: flex;
    justify-content: center;
    gap: var(--space-2xl);
    flex-wrap: wrap;
    margin: 0;
}

.stat {
    text-align: center;
}

.stat dt {
    font-size: 0.875rem;
    color: var(--color-text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.stat dd {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--color-primary);
    margin: var(--space-xs) 0 0;
}

/* Compare section */
.compare-section {
    max-width: 100%;
}

.compare-header {
    margin-bottom: var(--space-xl);
}

.compare-header h1 {
    margin: 0 0 var(--space-sm);
}

.compare-header p {
    color: var(--color-text-muted);
    margin: 0;
}

/* Editor panels - side by side */
.editor-panels {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-lg);
    margin-bottom: var(--space-md);
}

@media (max-width: 800px) {
    .editor-panels {
        grid-template-columns: 1fr;
    }
}

.editor-panel {
    display: flex;
    flex-direction: column;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: 8px;
    overflow: hidden;
}

.panel-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-sm) var(--space-md);
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
}

.panel-label {
    font-weight: 600;
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-muted);
}

.panel-actions {
    display: flex;
    gap: var(--space-xs);
}

.btn-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    padding: 0;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--color-text-muted);
    background: transparent;
    border: 1px solid var(--color-border);
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.15s, color 0.15s;
}

.btn-icon:hover,
.btn-icon:focus {
    background: var(--color-surface);
    color: var(--color-primary);
}

.editor-wrapper {
    flex: 1;
    display: flex;
    flex-direction: column;
}

.editor-textarea {
    flex: 1;
    font-family: var(--font-mono);
    font-size: 0.8125rem;
    line-height: 1.5;
    padding: var(--space-md);
    border: none;
    background: var(--color-surface);
    color: var(--color-text);
    resize: none;
    min-height: 280px;
    tab-size: 2;
}

.editor-textarea:focus {
    outline: none;
    box-shadow: inset 0 0 0 2px var(--color-primary);
}

.editor-textarea.editor-valid {
    box-shadow: inset 0 0 0 2px var(--color-success);
}

.editor-textarea.editor-error {
    box-shadow: inset 0 0 0 2px var(--color-error);
}

.editor-textarea.loading {
    opacity: 0.7;
}

.editor-textarea::placeholder {
    color: var(--color-text-muted);
    opacity: 0.7;
}

.editor-status {
    padding: var(--space-xs) var(--space-md);
    font-size: 0.75rem;
    min-height: 1.5rem;
    border-top: 1px solid var(--color-border);
}

.editor-status.status-valid {
    color: var(--color-success);
    background: rgba(10, 124, 66, 0.05);
}

.editor-status.status-error {
    color: var(--color-error);
    background: rgba(196, 30, 58, 0.05);
}

/* Form options */
.form-options {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-lg) var(--space-xl);
    margin-bottom: var(--space-lg);
}

.option-group {
    display: flex;
    flex-direction: column;
    gap: var(--space-xs);
}

.toggle-label {
    display: inline-flex;
    align-items: center;
    gap: var(--space-sm);
    cursor: pointer;
    font-size: 0.875rem;
    color: var(--color-text-muted);
}

.toggle-label input[type="checkbox"] {
    width: 18px;
    height: 18px;
    accent-color: var(--color-primary);
}

.toggle-text {
    user-select: none;
}

/* Form actions */
.form-actions {
    display: flex;
    align-items: center;
    gap: var(--space-md);
}

/* Empty state */
.empty-state {
    text-align: center;
    padding: var(--space-2xl);
    color: var(--color-text-muted);
    border: 2px dashed var(--color-border);
    border-radius: 8px;
    margin-top: var(--space-xl);
}

.empty-state p {
    margin: 0;
}

/* HTMX indicator */
.htmx-indicator {
    display: none;
    color: var(--color-text-muted);
}

.htmx-request .htmx-indicator {
    display: inline;
}

/* Results */
.result-card {
    margin-top: var(--space-xl);
    padding: var(--space-xl);
    border-radius: 8px;
    background: var(--color-surface);
    border: 2px solid var(--color-border);
}

.result-similar {
    border-color: var(--color-success);
}

.result-different {
    border-color: var(--color-warning);
}

.result-error {
    border-color: var(--color-error);
}

.result-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: var(--space-md);
    margin-bottom: var(--space-lg);
}

.result-header h2 {
    margin: 0;
}

.result-similar h2 {
    color: var(--color-success);
}

.result-different h2 {
    color: var(--color-warning);
}

.result-error h2 {
    color: var(--color-error);
}

/* Confidence Badge */
.confidence-badge {
    display: inline-flex;
    align-items: center;
    gap: var(--space-xs);
    padding: var(--space-xs) var(--space-sm);
    font-size: 0.8125rem;
    font-weight: 500;
    border-radius: 16px;
}

.confidence-high {
    background: rgba(10, 124, 66, 0.1);
    color: var(--color-success);
}

.confidence-medium {
    background: rgba(180, 83, 9, 0.1);
    color: var(--color-warning);
}

.confidence-low {
    background: rgba(196, 30, 58, 0.1);
    color: var(--color-error);
}

.confidence-icon {
    font-weight: 700;
}

/* Breakdown subtitle */
.breakdown-subtitle {
    color: var(--color-text-muted);
    font-size: 0.875rem;
    margin: 0 0 var(--space-md);
}

/* Weight badges */
.breakdown-item dt {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    min-width: 180px;
}

.algo-name {
    font-weight: 500;
}

.weight-badge {
    font-size: 0.6875rem;
    font-weight: 600;
    color: var(--color-text-muted);
    background: var(--color-bg);
    padding: 2px 6px;
    border-radius: 4px;
    border: 1px solid var(--color-border);
}

/* Confidence explanation */
.confidence-explanation {
    display: flex;
    align-items: flex-start;
    gap: var(--space-sm);
    padding: var(--space-md);
    margin-top: var(--space-lg);
    background: var(--color-bg);
    border-radius: 6px;
    font-size: 0.875rem;
    color: var(--color-text-muted);
}

.confidence-icon-small {
    flex-shrink: 0;
}

.score-display {
    text-align: center;
    margin-bottom: var(--space-xl);
}

.score-main {
    display: flex;
    flex-direction: column;
    gap: var(--space-xs);
}

.score-value {
    font-size: 3rem;
    font-weight: 700;
    color: var(--color-primary);
}

.score-label {
    font-size: 0.875rem;
    color: var(--color-text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.format-badges {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-xs);
    margin-top: var(--space-sm);
}

.format-badge {
    display: inline-block;
    font-size: 0.625rem;
    font-weight: 600;
    padding: 2px 8px;
    border-radius: 4px;
    text-transform: uppercase;
}

.format-json {
    background: rgba(245, 158, 11, 0.15);
    color: #b45309;
}

.format-xml {
    background: rgba(16, 185, 129, 0.15);
    color: #047857;
}

.format-html {
    background: rgba(139, 92, 246, 0.15);
    color: #6d28d9;
}

.format-separator {
    font-size: 0.75rem;
    color: var(--color-text-muted);
}

.mode-badge {
    display: inline-block;
    font-size: 0.625rem;
    font-weight: 600;
    padding: 2px 6px;
    border-radius: 4px;
    background: rgba(0, 102, 204, 0.1);
    color: var(--color-primary);
    text-transform: uppercase;
}

.result-card h3 {
    margin: 0 0 var(--space-md);
    font-size: 1rem;
}

.score-breakdown {
    margin: 0;
}

.breakdown-item {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    padding: var(--space-sm) 0;
}

.breakdown-item dt {
    min-width: 140px;
    font-weight: 500;
}

.breakdown-item dd {
    flex: 1;
    display: flex;
    align-items: center;
    gap: var(--space-md);
    margin: 0;
}

.progress-bar {
    flex: 1;
    height: 8px;
    background: var(--color-border);
    border-radius: 4px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: var(--color-primary);
    border-radius: 4px;
    transition: width 0.3s ease;
}

.score-percent {
    min-width: 50px;
    text-align: right;
    font-weight: 500;
}

/* Visual Diff */
.diff-section {
    margin-top: var(--space-xl);
    border-top: 1px solid var(--color-border);
    padding-top: var(--space-xl);
}

.diff-legend {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-md);
    margin-bottom: var(--space-lg);
    padding: var(--space-sm) var(--space-md);
    background: var(--color-bg);
    border-radius: 6px;
    font-size: 0.875rem;
}

.legend-item {
    display: inline-flex;
    align-items: center;
    gap: var(--space-xs);
}

.legend-exact .diff-icon { color: var(--color-success); }
.legend-synonym .diff-icon { color: #0066cc; }
.legend-partial .diff-icon { color: var(--color-warning); }
.legend-unmatched .diff-icon { color: var(--color-text-muted); }

@media (prefers-color-scheme: dark) {
    .legend-synonym .diff-icon { color: #4d9fff; }
}

.diff-table {
    border: 1px solid var(--color-border);
    border-radius: 8px;
    overflow: hidden;
}

.diff-header {
    display: grid;
    grid-template-columns: 60px 1fr 50px 1fr;
    background: var(--color-bg);
    font-weight: 600;
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-muted);
}

.diff-row {
    display: grid;
    grid-template-columns: 60px 1fr 50px 1fr;
    border-top: 1px solid var(--color-border);
    position: relative;
}

.diff-row:first-of-type {
    border-top: none;
}

.diff-cell {
    padding: var(--space-sm) var(--space-md);
    min-height: 48px;
    display: flex;
    align-items: center;
}

.diff-cell-type {
    justify-content: center;
    font-size: 1.25rem;
}

.diff-cell-connector {
    justify-content: center;
    font-family: var(--font-mono);
    color: var(--color-text-muted);
    font-size: 0.875rem;
}

.diff-cell-field {
    flex-direction: column;
    align-items: flex-start;
    justify-content: center;
}

.field-content {
    display: flex;
    flex-direction: column;
    gap: 2px;
    width: 100%;
}

.field-name {
    font-family: var(--font-mono);
    font-size: 0.8125rem;
    font-weight: 600;
    color: var(--color-text);
}

.field-value {
    font-family: var(--font-mono);
    font-size: 0.75rem;
    color: var(--color-text-muted);
    word-break: break-word;
}

.field-empty {
    color: var(--color-text-muted);
    font-style: italic;
}

/* Match type row colors */
.diff-exact {
    background: rgba(10, 124, 66, 0.05);
}
.diff-exact .diff-icon { color: var(--color-success); }
.diff-exact .connector { color: var(--color-success); }

.diff-synonym {
    background: rgba(0, 102, 204, 0.05);
}
.diff-synonym .diff-icon { color: #0066cc; }
.diff-synonym .connector { color: #0066cc; }

.diff-partial {
    background: rgba(180, 83, 9, 0.05);
}
.diff-partial .diff-icon { color: var(--color-warning); }
.diff-partial .connector { color: var(--color-warning); }

.diff-unmatched {
    background: rgba(128, 128, 128, 0.03);
}
.diff-unmatched .diff-icon { color: var(--color-text-muted); }

@media (prefers-color-scheme: dark) {
    .diff-exact { background: rgba(10, 124, 66, 0.1); }
    .diff-synonym { background: rgba(77, 159, 255, 0.1); }
    .diff-synonym .diff-icon { color: #4d9fff; }
    .diff-synonym .connector { color: #4d9fff; }
    .diff-partial { background: rgba(180, 83, 9, 0.1); }
    .diff-unmatched { background: rgba(128, 128, 128, 0.05); }
}

/* Row focus and hover states */
.diff-row:hover,
.diff-row:focus {
    outline: none;
    box-shadow: inset 0 0 0 2px var(--color-primary);
}

.diff-row:focus .field-name {
    text-decoration: underline;
}

/* Tooltip for synonym info */
.diff-tooltip {
    position: absolute;
    left: 60px;
    bottom: 100%;
    margin-bottom: 4px;
    padding: var(--space-xs) var(--space-sm);
    background: var(--color-text);
    color: var(--color-bg);
    border-radius: 4px;
    font-size: 0.75rem;
    white-space: nowrap;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.15s, visibility 0.15s;
    z-index: 10;
}

.diff-row:hover .diff-tooltip,
.diff-row:focus .diff-tooltip {
    opacity: 1;
    visibility: visible;
}

.tooltip-label {
    color: var(--color-text-muted);
}

.tooltip-value {
    font-family: var(--font-mono);
    font-weight: 600;
}

/* Accessibility patterns */
@media (forced-colors: active) {
    .diff-exact { border-left: 4px solid CanvasText; }
    .diff-synonym { border-left: 4px dashed CanvasText; }
    .diff-partial { border-left: 4px dotted CanvasText; }
    .diff-unmatched { border-left: 4px double CanvasText; }
}

/* Responsive diff table */
@media (max-width: 600px) {
    .diff-header {
        display: none;
    }

    .diff-row {
        display: flex;
        flex-direction: column;
        padding: var(--space-md);
        gap: var(--space-sm);
    }

    .diff-cell {
        padding: 0;
        min-height: auto;
    }

    .diff-cell-type {
        position: absolute;
        top: var(--space-md);
        right: var(--space-md);
    }

    .diff-cell-connector {
        display: none;
    }

    .diff-cell-field::before {
        content: attr(data-label);
        font-size: 0.75rem;
        text-transform: uppercase;
        color: var(--color-text-muted);
        margin-bottom: 2px;
    }
}

/* Example categories */
.example-category {
    margin: var(--space-xl) 0 var(--space-xs);
    padding-bottom: var(--space-sm);
    border-bottom: 2px solid var(--color-border);
    font-size: 1rem;
    font-weight: 600;
    color: var(--color-text-muted);
}

.example-category:first-of-type {
    margin-top: var(--space-lg);
}

.category-desc {
    margin: 0 0 var(--space-md);
    font-size: 0.875rem;
    color: var(--color-text-muted);
}

/* Example cards */
.example-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: var(--space-lg);
}

.example-card {
    background: var(--color-surface);
    padding: var(--space-lg);
    border-radius: 8px;
    border: 1px solid var(--color-border);
    display: flex;
    flex-direction: column;
}

.example-card h4 {
    margin: 0 0 var(--space-sm);
    font-size: 1rem;
}

.example-card p {
    color: var(--color-text-muted);
    font-size: 0.875rem;
    margin: 0 0 var(--space-sm);
    flex: 1;
}

.expected-score {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 600;
    font-family: var(--font-mono);
    padding: var(--space-xs) var(--space-sm);
    border-radius: 4px;
    margin-bottom: var(--space-md);
}

.score-high {
    background: rgba(10, 124, 66, 0.1);
    color: var(--color-success);
}

.score-medium {
    background: rgba(180, 83, 9, 0.1);
    color: var(--color-warning);
}

.score-low {
    background: rgba(196, 30, 58, 0.1);
    color: var(--color-error);
}

.score-note {
    font-size: 0.6875rem;
    font-weight: 500;
    color: var(--color-success);
}

@media (prefers-color-scheme: dark) {
    .score-high { background: rgba(10, 124, 66, 0.15); }
    .score-medium { background: rgba(180, 83, 9, 0.15); }
    .score-low { background: rgba(196, 30, 58, 0.15); }
}

/* Responsive */
@media (max-width: 600px) {
    main {
        padding: var(--space-lg) var(--space-md);
    }

    .stats {
        flex-direction: column;
        gap: var(--space-lg);
    }

    .breakdown-item {
        flex-direction: column;
        align-items: flex-start;
    }

    .breakdown-item dd {
        width: 100%;
    }
}

/* ========================================
   ANIMATIONS - GPU-accelerated only
   Using transform and opacity for 60fps
   ======================================== */

/* Slide in from bottom */
@keyframes slide-in {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.animate-slide-in {
    animation: slide-in 200ms ease-out forwards;
}

/* Fade in with delay support */
@keyframes fade-in {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

.animate-fade-in {
    opacity: 0;
    animation: fade-in 200ms ease-out forwards;
    animation-delay: var(--delay, 0ms);
}

/* Progress bar fill animation */
@keyframes progress-fill {
    from {
        width: 0;
    }
    to {
        width: var(--progress, 0%);
    }
}

.animate-progress {
    width: 0;
    animation: progress-fill 400ms ease-out forwards;
    animation-delay: 100ms;
}

/* Diff row staggered animation */
@keyframes diff-row-in {
    from {
        opacity: 0;
        transform: translateX(-10px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.animate-diff-row {
    opacity: 0;
    animation: diff-row-in 200ms ease-out forwards;
    animation-delay: calc(350ms + var(--row-delay, 0ms));
}

/* Button interactive feedback */
.btn {
    transform: translateZ(0);
    will-change: transform;
}

.btn:hover {
    transform: translateY(-1px);
}

.btn:active {
    transform: translateY(0) scale(0.98);
}

.btn-primary:hover {
    box-shadow: 0 4px 12px rgba(0, 102, 204, 0.25);
}

.btn-secondary:hover {
    box-shadow: 0 4px 12px rgba(0, 102, 204, 0.15);
}

/* Icon button feedback */
.btn-icon {
    transform: translateZ(0);
    will-change: transform;
}

.btn-icon:hover {
    transform: scale(1.1);
}

.btn-icon:active {
    transform: scale(0.95);
}

/* Example card hover */
.example-card {
    transform: translateZ(0);
    transition: transform 150ms ease-out, box-shadow 150ms ease-out;
}

.example-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.1);
}

/* Diff row hover pulse */
.diff-row {
    transform: translateZ(0);
    transition: transform 100ms ease-out;
}

.diff-row:hover {
    transform: scale(1.005);
}

/* Loading state pulse */
@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.5;
    }
}

.htmx-request .htmx-indicator {
    animation: pulse 1s ease-in-out infinite;
}

/* Score value emphasis on load */
.score-value {
    transform: translateZ(0);
}

/* ========================================
   API PAGE
   ======================================== */

.api-section {
    max-width: 900px;
}

.api-header {
    margin-bottom: var(--space-xl);
}

.api-header h1 {
    margin: 0 0 var(--space-sm);
}

.api-header p {
    color: var(--color-text-muted);
    margin: 0;
}

/* API Info */
.api-info {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: 8px;
    padding: var(--space-lg);
    margin-bottom: var(--space-xl);
}

.api-meta {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-xl);
    margin: 0;
}

.meta-item {
    display: flex;
    flex-direction: column;
    gap: var(--space-xs);
}

.meta-item dt {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-muted);
}

.meta-item dd {
    margin: 0;
    font-weight: 500;
}

.meta-item code {
    font-family: var(--font-mono);
    font-size: 0.875rem;
    background: var(--color-bg);
    padding: var(--space-xs) var(--space-sm);
    border-radius: 4px;
}

/* Endpoint Card */
.endpoint-card {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: 8px;
    overflow: hidden;
    margin-bottom: var(--space-xl);
}

.endpoint-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: var(--space-md);
    padding: var(--space-lg);
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
}

.endpoint-method-path {
    display: flex;
    align-items: center;
    gap: var(--space-md);
}

.method-badge {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    padding: var(--space-xs) var(--space-sm);
    border-radius: 4px;
}

.method-post {
    background: rgba(16, 185, 129, 0.15);
    color: #047857;
}

.method-get {
    background: rgba(59, 130, 246, 0.15);
    color: #1d4ed8;
}

@media (prefers-color-scheme: dark) {
    .method-post {
        background: rgba(16, 185, 129, 0.2);
        color: #34d399;
    }
    .method-get {
        background: rgba(59, 130, 246, 0.2);
        color: #60a5fa;
    }
}

.endpoint-path {
    font-family: var(--font-mono);
    font-size: 1rem;
    font-weight: 600;
}

.btn-try-it {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: var(--touch-target);
    padding: var(--space-sm) var(--space-lg);
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--color-primary);
    background: transparent;
    border: 2px solid var(--color-primary);
    border-radius: 6px;
    cursor: pointer;
    transition: background-color 0.15s, color 0.15s;
}

.btn-try-it:hover,
.btn-try-it:focus {
    background: var(--color-primary);
    color: white;
}

.btn-try-it[aria-expanded="true"] {
    background: var(--color-primary);
    color: white;
}

.endpoint-description {
    padding: var(--space-lg);
    border-bottom: 1px solid var(--color-border);
}

.endpoint-description p {
    margin: 0;
    color: var(--color-text-muted);
}

.endpoint-details {
    padding: var(--space-lg);
}

.endpoint-details h3 {
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-muted);
    margin: 0 0 var(--space-md);
}

.endpoint-details h3:not(:first-child) {
    margin-top: var(--space-xl);
}

/* Parameters Table */
.params-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.875rem;
}

.params-table th {
    text-align: left;
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-muted);
    padding: var(--space-sm) var(--space-md);
    border-bottom: 2px solid var(--color-border);
}

.params-table td {
    padding: var(--space-md);
    border-bottom: 1px solid var(--color-border);
    vertical-align: top;
}

.params-table code {
    font-family: var(--font-mono);
    font-size: 0.8125rem;
    font-weight: 600;
}

.type-badge {
    display: inline-block;
    font-size: 0.6875rem;
    font-weight: 600;
    padding: 2px 6px;
    border-radius: 4px;
    background: rgba(139, 92, 246, 0.1);
    color: #6d28d9;
}

.required-badge {
    display: inline-block;
    font-size: 0.6875rem;
    font-weight: 600;
    padding: 2px 6px;
    border-radius: 4px;
    background: rgba(239, 68, 68, 0.1);
    color: #dc2626;
}

.optional-badge {
    display: inline-block;
    font-size: 0.6875rem;
    font-weight: 600;
    padding: 2px 6px;
    border-radius: 4px;
    background: rgba(156, 163, 175, 0.2);
    color: var(--color-text-muted);
}

@media (prefers-color-scheme: dark) {
    .type-badge {
        background: rgba(139, 92, 246, 0.2);
        color: #a78bfa;
    }
    .required-badge {
        background: rgba(239, 68, 68, 0.2);
        color: #f87171;
    }
}

/* Response Schema */
.response-schema {
    background: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: 6px;
    overflow: hidden;
}

.schema-preview {
    margin: 0;
    padding: var(--space-md);
    overflow-x: auto;
}

.schema-preview code {
    font-family: var(--font-mono);
    font-size: 0.8125rem;
    line-height: 1.5;
}

.response-fields {
    margin-top: var(--space-lg);
}

.response-fields summary {
    cursor: pointer;
    font-weight: 500;
    color: var(--color-primary);
    padding: var(--space-sm) 0;
}

.response-fields summary:hover {
    text-decoration: underline;
}

.response-fields[open] summary {
    margin-bottom: var(--space-md);
}

/* API Playground */
.api-playground {
    border-top: 1px solid var(--color-border);
    padding: var(--space-lg);
    background: var(--color-bg);
    display: none;
}

.api-playground[aria-hidden="false"] {
    display: block;
}

.playground-title {
    font-size: 1rem;
    margin: 0 0 var(--space-lg);
}

.playground-form {
    display: flex;
    flex-direction: column;
    gap: var(--space-lg);
}

.playground-params {
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
}

.param-group {
    display: flex;
    flex-direction: column;
    gap: var(--space-xs);
}

.param-group-inline {
    flex-direction: row;
    align-items: center;
}

.param-label {
    font-size: 0.875rem;
    font-weight: 500;
}

.param-label code {
    font-family: var(--font-mono);
    background: var(--color-surface);
    padding: 2px 6px;
    border-radius: 4px;
}

.required-indicator {
    color: var(--color-error);
    margin-left: var(--space-xs);
}

.param-textarea {
    font-family: var(--font-mono);
    font-size: 0.8125rem;
    line-height: 1.5;
    padding: var(--space-md);
    border: 1px solid var(--color-border);
    border-radius: 6px;
    background: var(--color-surface);
    color: var(--color-text);
    resize: vertical;
    min-height: 100px;
}

.param-textarea:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(0, 102, 204, 0.1);
}

.playground-actions {
    display: flex;
    gap: var(--space-md);
}

.btn-execute {
    min-width: 120px;
}

.example-select {
    padding: var(--space-sm) var(--space-md);
    font-size: 0.875rem;
    font-family: var(--font-sans);
    color: var(--color-text);
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: 6px;
    cursor: pointer;
    min-height: var(--touch-target);
}

.example-select:hover,
.example-select:focus {
    border-color: var(--color-primary);
    outline: none;
}

.example-select option {
    padding: var(--space-sm);
}

/* Rich API Response */
.rich-response {
    margin-bottom: var(--space-md);
}

.empty-response,
.loading-state,
.error-state {
    padding: var(--space-xl);
    text-align: center;
    color: var(--color-text-muted);
    background: var(--color-bg);
    border-radius: 6px;
}

.error-state {
    color: var(--color-error);
    background: rgba(196, 30, 58, 0.05);
}

.raw-json-toggle {
    margin-top: var(--space-md);
}

.raw-json-toggle summary {
    cursor: pointer;
    font-size: 0.875rem;
    color: var(--color-text-muted);
    padding: var(--space-sm) 0;
}

.raw-json-toggle summary:hover {
    color: var(--color-primary);
}

.api-result-card {
    background: var(--color-bg);
    border-radius: 8px;
    padding: var(--space-lg);
    border: 2px solid var(--color-border);
}

.api-result-card.similar {
    border-color: var(--color-success);
}

.api-result-card.different {
    border-color: var(--color-warning);
}

.api-score-section {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: var(--space-md);
    margin-bottom: var(--space-lg);
    padding-bottom: var(--space-lg);
    border-bottom: 1px solid var(--color-border);
}

.api-score-main {
    display: flex;
    flex-direction: column;
    gap: var(--space-xs);
}

.api-score-value {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--color-primary);
    line-height: 1;
}

.api-score-label {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-muted);
}

.api-score-badges {
    display: flex;
    gap: var(--space-sm);
    flex-wrap: wrap;
}

.api-badge {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 600;
    padding: var(--space-xs) var(--space-sm);
    border-radius: 16px;
    text-transform: capitalize;
}

.api-badge-similar {
    background: rgba(10, 124, 66, 0.15);
    color: var(--color-success);
}

.api-badge-different {
    background: rgba(180, 83, 9, 0.15);
    color: var(--color-warning);
}

.api-badge-confidence-high {
    background: rgba(10, 124, 66, 0.1);
    color: var(--color-success);
}

.api-badge-confidence-medium {
    background: rgba(180, 83, 9, 0.1);
    color: var(--color-warning);
}

.api-badge-confidence-low {
    background: rgba(196, 30, 58, 0.1);
    color: var(--color-error);
}

.api-breakdown h4 {
    font-size: 0.875rem;
    font-weight: 600;
    margin: 0 0 var(--space-md);
    color: var(--color-text-muted);
}

.api-breakdown-items {
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
}

.api-breakdown-item {
    display: grid;
    grid-template-columns: 140px 1fr 60px;
    align-items: center;
    gap: var(--space-md);
}

.api-breakdown-header {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.api-algo-name {
    font-weight: 500;
    font-size: 0.875rem;
}

.api-algo-weight {
    font-size: 0.6875rem;
    color: var(--color-text-muted);
    background: var(--color-surface);
    padding: 2px 6px;
    border-radius: 4px;
}

.api-progress {
    height: 8px;
    background: var(--color-border);
    border-radius: 4px;
    overflow: hidden;
}

.api-progress-bar {
    height: 100%;
    background: var(--color-primary);
    border-radius: 4px;
    transition: width 0.4s ease-out;
}

.api-algo-score {
    font-weight: 600;
    font-size: 0.875rem;
    text-align: right;
}

@media (max-width: 500px) {
    .api-breakdown-item {
        grid-template-columns: 1fr;
        gap: var(--space-xs);
    }

    .api-algo-score {
        text-align: left;
    }
}

/* Playground Result */
.playground-result {
    margin-top: var(--space-xl);
    border: 1px solid var(--color-border);
    border-radius: 6px;
    overflow: hidden;
    background: var(--color-surface);
}

.result-tabs {
    display: flex;
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
}

.result-tab {
    padding: var(--space-sm) var(--space-lg);
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-text-muted);
    background: transparent;
    border: none;
    border-bottom: 2px solid transparent;
    cursor: pointer;
    transition: color 0.15s, border-color 0.15s;
}

.result-tab:hover {
    color: var(--color-text);
}

.result-tab.active {
    color: var(--color-primary);
    border-bottom-color: var(--color-primary);
}

.result-panel {
    padding: var(--space-md);
}

.result-panel[hidden] {
    display: none;
}

.response-status {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    margin-bottom: var(--space-md);
    min-height: 24px;
}

.status-code {
    font-size: 0.875rem;
    font-weight: 600;
    padding: var(--space-xs) var(--space-sm);
    border-radius: 4px;
}

.status-success {
    background: rgba(16, 185, 129, 0.15);
    color: #047857;
}

.status-error {
    background: rgba(239, 68, 68, 0.15);
    color: #dc2626;
}

.status-pending {
    color: var(--color-text-muted);
}

.status-time {
    font-size: 0.75rem;
    color: var(--color-text-muted);
}

.response-body {
    margin: 0;
    padding: var(--space-md);
    background: var(--color-bg);
    border-radius: 6px;
    overflow-x: auto;
    max-height: 400px;
    overflow-y: auto;
}

.response-body code {
    font-family: var(--font-mono);
    font-size: 0.8125rem;
    line-height: 1.5;
}

.error-text {
    color: var(--color-error);
}

/* Code Snippets */
.code-snippet {
    margin: 0;
    padding: var(--space-md);
    background: var(--color-bg);
    border-radius: 6px;
    overflow-x: auto;
}

.code-snippet code {
    font-family: var(--font-mono);
    font-size: 0.8125rem;
    line-height: 1.5;
}

.btn-copy {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    margin-top: var(--space-sm);
    padding: var(--space-xs) var(--space-md);
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--color-text-muted);
    background: transparent;
    border: 1px solid var(--color-border);
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.15s, color 0.15s;
}

.btn-copy:hover {
    background: var(--color-bg);
    color: var(--color-text);
}

.btn-copy.copied {
    background: var(--color-success);
    color: white;
    border-color: var(--color-success);
}

/* JSON Syntax Highlighting */
.json-key {
    color: #0066cc;
}

.json-string {
    color: #0a7c42;
}

.json-number {
    color: #b45309;
}

.json-boolean {
    color: #6d28d9;
}

.json-null {
    color: var(--color-text-muted);
}

@media (prefers-color-scheme: dark) {
    .json-key { color: #4d9fff; }
    .json-string { color: #34d399; }
    .json-number { color: #fbbf24; }
    .json-boolean { color: #a78bfa; }
}

/* API Notes */
.api-notes {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: 8px;
    padding: var(--space-lg);
}

.api-notes h2 {
    font-size: 1rem;
    margin: 0 0 var(--space-md);
}

.notes-list {
    margin: 0;
    padding-left: var(--space-lg);
}

.notes-list li {
    margin-bottom: var(--space-sm);
    color: var(--color-text-muted);
}

.notes-list li:last-child {
    margin-bottom: 0;
}

.notes-list strong {
    color: var(--color-text);
}

.notes-list code {
    font-family: var(--font-mono);
    font-size: 0.8125rem;
    background: var(--color-bg);
    padding: 2px 6px;
    border-radius: 4px;
}

/* ========================================
   REDUCED MOTION - Accessibility
   ======================================== */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }

    .animate-slide-in,
    .animate-fade-in,
    .animate-progress,
    .animate-diff-row {
        opacity: 1;
        transform: none;
        animation: none;
    }

    .animate-progress {
        width: var(--progress, 0%);
    }

    .btn:hover,
    .btn:active,
    .btn-icon:hover,
    .btn-icon:active,
    .example-card:hover,
    .diff-row:hover {
        transform: none;
    }
}