/* ============================================================
   SUBTEMPLATES.CSS — Shared styles for all subpages
   Includes: variables, layout, nav, filter panels, and all
   common UI components (selects, checkboxes, sliders, charts…)
   ============================================================ */

/* --- CSS Variables — Dark by default --- */
:root {
    --bg-primary: #0a0a0a;
    --bg-secondary: #141414;
    --bg-card: #1a1a1a;
    --bg-card-hover: #222222;
    --text-primary: #f0f0f0;
    --text-secondary: #a0a0a0;
    --text-muted: #666666;
    --accent-red: #c41e3a;
    --accent-red-hover: #e52a4a;
    --accent-gold: #d4af37;
    --accent-silver: #c0c0c0;
    --accent-blue: #4a9eff;
    --border-subtle: rgba(255, 255, 255, 0.08);
    --border-medium: rgba(255, 255, 255, 0.12);
    --shadow-card: 0 4px 20px rgba(0, 0, 0, 0.4);
    --warning-bg: rgba(212, 175, 55, 0.1);
    --warning-border: var(--accent-gold);
}

[data-theme="light"] {
    --bg-primary: #f5f5f5;
    --bg-secondary: #e8e8e8;
    --bg-card: #ffffff;
    --bg-card-hover: #fafafa;
    --text-primary: #1a1a1a;
    --text-secondary: #555555;
    --text-muted: #888888;
    --accent-red: #b01830;
    --accent-red-hover: #d01e3a;
    --accent-blue: #2980b9;
    --border-subtle: rgba(0, 0, 0, 0.08);
    --border-medium: rgba(0, 0, 0, 0.12);
    --shadow-card: 0 4px 20px rgba(0, 0, 0, 0.1);
    --warning-bg: #fff8e6;
    --warning-border: #d4a500;
}

/* --- Reset & Base --- */

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Source Sans 3', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--bg-primary);
    transition: background-color 0.3s, color 0.3s;
    min-height: 100vh;
}

/* Subtle texture overlay */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)' opacity='0.03'/%3E%3C/svg%3E");
    pointer-events: none;
    z-index: 0;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 20px;
    position: relative;
    z-index: 1;
}

/* --- Header / Disclosure Banner --- */

.header-banner {
    display: block;
    background: var(--warning-bg);
    padding: 14px 18px;
    margin-bottom: 24px;
    border-left: 3px solid var(--warning-border);
    border-radius: 4px;
    font-size: 0.9em;
    color: var(--text-secondary);
}

.header-banner a {
    color: var(--accent-gold);
    text-decoration: none;
    font-weight: 600;
}

.header-banner a:hover {
    text-decoration: underline;
}

/* --- Navigation --- */

.nav-links {
    margin-top: 12px;
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
    align-items: center;
}

.nav-button {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 16px;
    border-radius: 4px;
    font-size: 0.9em;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.2s ease;
    border: none;
    cursor: pointer;
    font-family: inherit;
}

.nav-button.home {
    background: var(--bg-card);
    color: var(--text-primary);
    border: 1px solid var(--border-subtle);
}

.nav-button.home:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-medium);
}

.nav-button.support {
    background: var(--accent-red);
    color: white;
}

.nav-button.support:hover {
    background: var(--accent-red-hover);
}

.nav-button.theme-toggle {
    background: var(--bg-card);
    color: var(--text-primary);
    border: 1px solid var(--border-subtle);
}

.nav-button.theme-toggle:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-medium);
}

/* --- Page Layout --- */

.main-layout {
    display: flex;
    gap: 24px;
    align-items: stretch;
}

.sidebar {
    width: 260px;
    flex-shrink: 0;
}

/* Single-panel sidebar: stretch to match content height */
.sidebar:has(.filter-panel:only-child) .filter-panel {
    height: 100%;
    display: flex;
    flex-direction: column;
}

.sidebar:has(.filter-panel:only-child) .filter-panel .filter-content.show {
    flex-grow: 1;
    max-height: none;
    overflow-y: auto;
}

.content {
    flex-grow: 1;
    min-width: 0;
}

/* --- Filter Panels --- */

.filter-panel {
    background: var(--bg-card);
    border-radius: 8px;
    border: 1px solid var(--border-subtle);
    box-shadow: var(--shadow-card);
    margin-bottom: 16px;
    overflow: hidden;
}

.filter-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 16px;
    cursor: pointer;
    user-select: none;
    border-bottom: 1px solid var(--border-subtle);
    transition: background 0.2s ease;
}

.filter-header:hover {
    background: var(--bg-card-hover);
}

.filter-header h3 {
    font-family: 'Bebas Neue', sans-serif;
    font-size: 1rem;
    font-weight: 400;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--text-primary);
    margin: 0;
}

.filter-header .toggle-icon {
    font-size: 0.8em;
    color: var(--text-muted);
    transition: transform 0.2s ease;
}

.filter-header.expanded .toggle-icon {
    transform: rotate(180deg);
}

.filter-content {
    padding: 12px 16px;
    display: none;
    max-height: 300px;
    overflow-y: auto;
}

.filter-content.show {
    display: block;
}

/* --- Filter Content: Radio Labels --- */

.filter-content label {
    display: flex;
    align-items: center;
    padding: 8px 10px;
    margin: 2px 0;
    cursor: pointer;
    font-size: 0.9em;
    color: var(--text-secondary);
    border-radius: 4px;
    transition: all 0.15s ease;
}

.filter-content label:hover {
    background: var(--bg-card-hover);
    color: var(--text-primary);
}

.filter-content label.selected {
    background: rgba(196, 30, 58, 0.15);
    color: var(--accent-red);
}

.filter-content input[type="radio"] {
    appearance: none;
    width: 16px;
    height: 16px;
    border: 2px solid var(--border-medium);
    border-radius: 50%;
    margin-right: 10px;
    position: relative;
    cursor: pointer;
    transition: all 0.15s ease;
}

.filter-content input[type="radio"]:checked {
    border-color: var(--accent-red);
    background: var(--accent-red);
}

.filter-content input[type="radio"]:checked::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 6px;
    height: 6px;
    background: white;
    border-radius: 50%;
}

/* --- Filter Content: Select Dropdowns --- */

.filter-content select {
    width: 100%;
    padding: 10px 12px;
    margin-top: 6px;
    border: 1px solid var(--border-medium);
    border-radius: 4px;
    background: var(--bg-secondary);
    color: var(--text-primary);
    font-size: 0.9em;
    font-family: inherit;
    cursor: pointer;
    transition: border-color 0.2s ease;
}

.filter-content select:hover,
.filter-content select:focus {
    border-color: var(--accent-red);
    outline: none;
}

.filter-content select option {
    background: var(--bg-card);
    color: var(--text-primary);
}

.filter-content select optgroup {
    background: var(--bg-secondary);
    color: var(--text-muted);
    font-style: normal;
    font-weight: 600;
}

/* --- Select Labels --- */

.select-label {
    display: block;
    font-size: 0.85em;
    color: var(--text-secondary);
    margin-bottom: 4px;
    margin-top: 12px;
}

.select-label:first-child {
    margin-top: 0;
}

/* --- Year Slider --- */

.year-slider-container {
    margin-top: 16px;
    padding-top: 12px;
    border-top: 1px solid var(--border-subtle);
}

.year-slider-container label,
.year-slider-container > span,
.year-slider-container .slider-label {
    display: block;
    font-size: 0.85em;
    color: var(--text-secondary);
    margin-bottom: 8px;
    padding: 0;
}

.year-display {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 8px;
}

.year-display span,
.year-display .year-bound,
.year-display .year-min,
.year-display .year-max {
    font-size: 0.8em;
    color: var(--text-muted);
}

.year-value {
    font-family: 'Bebas Neue', sans-serif;
    font-size: 1.5rem !important;
    color: var(--accent-red) !important;
    letter-spacing: 0.04em;
}

input[type="range"],
.filter-content input[type="range"] {
    width: 100%;
    height: 6px;
    -webkit-appearance: none;
    appearance: none;
    background: var(--bg-secondary);
    border-radius: 3px;
    outline: none;
    cursor: pointer;
}

input[type="range"]::-webkit-slider-thumb,
.filter-content input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--accent-red);
    cursor: pointer;
    border: 2px solid var(--bg-card);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
    transition: transform 0.15s ease;
}

input[type="range"]::-webkit-slider-thumb:hover,
.filter-content input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.15);
}

input[type="range"]::-moz-range-thumb,
.filter-content input[type="range"]::-moz-range-thumb {
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--accent-red);
    cursor: pointer;
    border: 2px solid var(--bg-card);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
}

/* --- Toggle Button --- */

.toggle-container {
    margin-top: 16px;
    padding-top: 12px;
    border-top: 1px solid var(--border-subtle);
}

.toggle-button {
    width: 100%;
    padding: 10px 14px;
    font-size: 0.85em;
    font-family: inherit;
    font-weight: 600;
    background: var(--bg-secondary);
    color: var(--text-secondary);
    border: 1px solid var(--border-medium);
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.2s ease;
}

.toggle-button:hover {
    background: var(--bg-card-hover);
    color: var(--text-primary);
    border-color: var(--accent-red);
}

.toggle-button.active {
    background: rgba(196, 30, 58, 0.15);
    color: var(--accent-red);
    border-color: var(--accent-red);
}

/* --- Compare Button --- */

.compare-btn {
    display: block;
    width: 100%;
    margin-top: 16px;
    padding: 10px 16px;
    font-size: 0.9em;
    font-weight: 600;
    font-family: inherit;
    background: var(--accent-red);
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.2s ease;
}

.compare-btn:hover:not(:disabled) {
    background: var(--accent-red-hover);
}

.compare-btn:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

/* --- Genre / Section Labels --- */

.genre-section-label,
.section-label {
    display: block;
    font-size: 0.85em;
    color: var(--text-secondary);
    margin-top: 16px;
    margin-bottom: 8px;
    padding-top: 12px;
    border-top: 1px solid var(--border-subtle);
}

/* --- Genre / Decade Filter Buttons (All/None) --- */

.genre-filter-buttons,
.decade-filter-buttons {
    display: flex;
    gap: 8px;
    margin-bottom: 10px;
}

.genre-filter-buttons button,
.decade-filter-buttons button {
    flex: 1;
    padding: 6px 10px;
    font-size: 0.8em;
    font-family: inherit;
    background: var(--bg-secondary);
    color: var(--text-secondary);
    border: 1px solid var(--border-medium);
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.15s ease;
}

.genre-filter-buttons button:hover,
.decade-filter-buttons button:hover {
    background: var(--bg-card-hover);
    color: var(--text-primary);
    border-color: var(--accent-red);
}

/* --- Checkbox Filters Container (scrollable list) --- */

.checkbox-filters {
    max-height: 320px;
    overflow-y: auto;
    padding-right: 4px;
}

.checkbox-filters::-webkit-scrollbar {
    width: 6px;
}

.checkbox-filters::-webkit-scrollbar-track {
    background: var(--bg-secondary);
    border-radius: 3px;
}

.checkbox-filters::-webkit-scrollbar-thumb {
    background: var(--border-medium);
    border-radius: 3px;
}

.checkbox-filters::-webkit-scrollbar-thumb:hover {
    background: var(--text-muted);
}

/* --- Genre / Decade Checkbox Items --- */

.genre-checkbox,
.decade-checkbox {
    display: flex;
    align-items: center;
    padding: 7px 8px;
    border-radius: 4px;
    margin-bottom: 2px;
    transition: background 0.15s ease;
}

.genre-checkbox:hover,
.decade-checkbox:hover {
    background: var(--bg-card-hover);
}

.genre-checkbox input[type="checkbox"],
.decade-checkbox input[type="checkbox"] {
    appearance: none;
    width: 16px;
    height: 16px;
    border: 2px solid var(--border-medium);
    border-radius: 3px;
    margin-right: 8px;
    cursor: pointer;
    position: relative;
    flex-shrink: 0;
    transition: all 0.15s ease;
}

.genre-checkbox input[type="checkbox"]:checked,
.decade-checkbox input[type="checkbox"]:checked {
    background: var(--accent-red);
    border-color: var(--accent-red);
}

.genre-checkbox input[type="checkbox"]:checked::after,
.decade-checkbox input[type="checkbox"]:checked::after {
    content: '✔';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: white;
    font-size: 11px;
    font-weight: bold;
}

.genre-checkbox label,
.decade-checkbox label {
    display: flex;
    align-items: center;
    cursor: pointer;
    font-size: 0.85em;
    color: var(--text-secondary);
    padding: 0;
    margin: 0;
    flex-grow: 1;
}

.genre-checkbox:hover label,
.decade-checkbox:hover label {
    color: var(--text-primary);
}

.genre-checkbox label:hover,
.decade-checkbox label:hover {
    background: transparent;
}

/* --- Color Indicator Boxes --- */

.genre-color-box,
.decade-color-box {
    width: 14px;
    height: 14px;
    border-radius: 3px;
    margin-right: 8px;
    flex-shrink: 0;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

/* --- Standalone Checkbox Filter (genre_leaders) --- */

.checkbox-filter {
    margin-top: 16px;
    padding: 12px;
    background: var(--bg-secondary);
    border-radius: 4px;
}

.checkbox-filter label {
    display: flex;
    align-items: center;
    cursor: pointer;
    font-size: 0.9em;
    color: var(--text-primary);
    padding: 0;
    margin: 0;
}

.checkbox-filter label:hover {
    background: transparent;
}

.checkbox-filter input[type="checkbox"] {
    appearance: none;
    width: 18px;
    height: 18px;
    border: 2px solid var(--border-medium);
    border-radius: 4px;
    margin-right: 10px;
    cursor: pointer;
    position: relative;
    transition: all 0.15s ease;
}

.checkbox-filter input[type="checkbox"]:checked {
    background: var(--accent-red);
    border-color: var(--accent-red);
}

.checkbox-filter input[type="checkbox"]:checked::after {
    content: '✔';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: white;
    font-size: 12px;
    font-weight: bold;
}

.checkbox-filter .hint {
    font-size: 0.75em;
    color: var(--text-muted);
    margin-top: 6px;
    margin-left: 28px;
}

/* --- Info Box --- */

.info-box {
    margin-top: 16px;
    padding: 12px;
    background: rgba(74, 158, 255, 0.1);
    border-left: 3px solid var(--accent-blue);
    border-radius: 4px;
    font-size: 0.85em;
    color: var(--text-secondary);
}

.info-box strong {
    display: block;
    color: var(--accent-blue);
    margin-bottom: 4px;
}

/* --- Warning Box --- */

.warning-box {
    padding: 12px 16px;
    background: rgba(212, 175, 55, 0.15);
    border-left: 3px solid var(--accent-gold);
    border-radius: 4px;
    margin-bottom: 20px;
    font-size: 0.9em;
    color: var(--text-secondary);
}

.warning-box strong {
    color: var(--accent-gold);
}

/* --- Chart Header --- */

.chart-header {
    margin-bottom: 16px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--border-subtle);
}

.chart-header h2 {
    font-family: 'Bebas Neue', sans-serif;
    font-size: 1.5rem;
    font-weight: 400;
    letter-spacing: 0.04em;
    color: var(--text-primary);
    margin: 0;
}

.chart-subtitle {
    font-size: 0.9em;
    color: var(--text-secondary);
    margin-top: 4px;
}

/* --- Chart Panel & Container --- */

.chart-panel {
    background: var(--bg-card);
    border-radius: 8px;
    border: 1px solid var(--border-subtle);
    box-shadow: var(--shadow-card);
    padding: 24px;
    min-height: 600px;
}

.chart-title {
    font-family: 'Bebas Neue', sans-serif;
    font-size: 1.5rem;
    font-weight: 400;
    letter-spacing: 0.04em;
    color: var(--text-primary);
    margin-bottom: 20px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--border-subtle);
}

#chartContainer {
    position: relative;
    height: 550px;
    min-height: 550px;
}

#chartContainer canvas {
    max-width: 100%;
}

#chartCanvas {
    position: relative;
    width: 100%;
    min-height: 400px;
}

/* --- Stats Row (continent comparison) --- */

.stats-row {
    display: flex;
    gap: 12px;
    margin-bottom: 20px;
    flex-wrap: wrap;
}

.stat-card {
    flex: 1;
    min-width: 120px;
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: 8px;
    padding: 14px 16px;
    text-align: center;
    box-shadow: var(--shadow-card);
}

.stat-card .stat-label {
    font-size: 0.8em;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.stat-card .stat-value {
    font-family: 'Bebas Neue', sans-serif;
    font-size: 1.6rem;
    color: var(--text-primary);
    margin: 4px 0;
    letter-spacing: 0.02em;
}

/* --- Decade Charts Grid (continent comparison) --- */

.decade-charts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 20px;
    margin-top: 20px;
}

.decade-chart-card {
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: 8px;
    padding: 16px;
    box-shadow: var(--shadow-card);
}

.decade-chart-card canvas {
    max-width: 100%;
}

/* --- Selected Countries Tags (multi-country comparison) --- */

.selected-countries {
    margin-top: 12px;
}

.selected-countries h4 {
    font-size: 0.85em;
    color: var(--text-secondary);
    margin-bottom: 8px;
    font-weight: 400;
}

.country-tag {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 5px 10px;
    margin: 3px 4px 3px 0;
    background: rgba(196, 30, 58, 0.15);
    color: var(--accent-red);
    border-radius: 4px;
    font-size: 0.82em;
    font-weight: 600;
}

.country-tag .color-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    flex-shrink: 0;
}

.country-tag .remove {
    cursor: pointer;
    font-size: 1.1em;
    line-height: 1;
    opacity: 0.7;
    transition: opacity 0.15s ease;
}

.country-tag .remove:hover {
    opacity: 1;
}

/* --- View Mode Toggle Buttons --- */

.view-mode-toggle,
.view-mode-buttons {
    display: flex;
    gap: 6px;
}

.view-mode-toggle {
    margin-top: 14px;
    padding-top: 12px;
    border-top: 1px solid var(--border-subtle);
}

.view-mode-section {
    margin-top: 16px;
    padding-top: 12px;
    border-top: 1px solid var(--border-subtle);
}

.view-mode-label {
    display: block;
    font-size: 0.85em;
    color: var(--text-secondary);
    margin-bottom: 8px;
}

.view-mode-toggle button,
.view-mode-buttons button {
    flex: 1;
    padding: 8px 10px;
    font-size: 0.8em;
    font-family: inherit;
    background: var(--bg-secondary);
    color: var(--text-secondary);
    border: 1px solid var(--border-medium);
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.15s ease;
}

.view-mode-toggle button:hover,
.view-mode-buttons button:hover {
    background: var(--bg-card-hover);
    color: var(--text-primary);
    border-color: var(--accent-red);
}

.view-mode-toggle button.active,
.view-mode-buttons button.active {
    background: rgba(196, 30, 58, 0.15);
    color: var(--accent-red);
    border-color: var(--accent-red);
}

/* --- Region Info Box (regions page) --- */

.region-info {
    margin-top: 14px;
    padding: 10px 12px;
    background: rgba(74, 158, 255, 0.08);
    border-left: 3px solid var(--accent-blue);
    border-radius: 4px;
    font-size: 0.8em;
    color: var(--text-secondary);
    line-height: 1.5;
    display: none;
}

.region-info strong {
    display: block;
    color: var(--accent-blue);
    margin-bottom: 4px;
    font-size: 0.95em;
}

/* --- Loading State --- */

.loading {
    display: flex;
    align-items: center;
    justify-content: center;
    height: 300px;
    color: var(--text-muted);
    font-size: 1rem;
}

/* --- Explanation Button --- */

.nav-button.explanation {
    background: var(--bg-card);
    color: var(--text-primary);
    border: 1px solid var(--border-subtle);
}

.nav-button.explanation:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-medium);
}

.nav-button.explanation.active {
    background: rgba(196, 30, 58, 0.15);
    border-color: var(--accent-red);
    color: var(--accent-red);
}

/* --- Explanation Overlay --- */

.explanation-backdrop {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 99;
}

.explanation-backdrop.show {
    display: block;
}

.explanation-overlay {
    display: none;
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 60%;
    max-width: 720px;
    max-height: 70vh;
    overflow-y: auto;
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: 8px;
    box-shadow: 0 8px 40px rgba(0, 0, 0, 0.5);
    padding: 32px;
    z-index: 100;
    color: var(--text-secondary);
    font-size: 0.95em;
    line-height: 1.8;
}

.explanation-overlay.show {
    display: block;
}

.explanation-overlay h3 {
    font-family: 'Bebas Neue', sans-serif;
    font-size: 1.4rem;
    font-weight: 400;
    letter-spacing: 0.06em;
    color: var(--text-primary);
    margin-bottom: 16px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--border-subtle);
}

.explanation-overlay p {
    margin-bottom: 12px;
}

.explanation-overlay .close-btn {
    position: absolute;
    top: 12px;
    right: 16px;
    background: none;
    border: none;
    color: var(--text-muted);
    font-size: 1.4em;
    cursor: pointer;
    padding: 4px 8px;
    border-radius: 4px;
    transition: all 0.15s ease;
}

.explanation-overlay .close-btn:hover {
    color: var(--text-primary);
    background: var(--bg-card-hover);
}

.explanation-overlay::-webkit-scrollbar {
    width: 6px;
}

.explanation-overlay::-webkit-scrollbar-track {
    background: var(--bg-secondary);
    border-radius: 3px;
}

.explanation-overlay::-webkit-scrollbar-thumb {
    background: var(--border-medium);
    border-radius: 3px;
}

.explanation-overlay::-webkit-scrollbar-thumb:hover {
    background: var(--text-muted);
}

/* --- Scrollbar styling for filter content --- */

.filter-content::-webkit-scrollbar {
    width: 6px;
}

.filter-content::-webkit-scrollbar-track {
    background: var(--bg-secondary);
    border-radius: 3px;
}

.filter-content::-webkit-scrollbar-thumb {
    background: var(--border-medium);
    border-radius: 3px;
}

.filter-content::-webkit-scrollbar-thumb:hover {
    background: var(--text-muted);
}

/* --- Responsive --- */

@media (max-width: 900px) {
    .main-layout {
        flex-direction: column;
    }

    .sidebar {
        width: 100%;
        display: flex;
        flex-wrap: wrap;
        gap: 12px;
    }

    .filter-panel {
        flex: 1;
        min-width: 200px;
        margin-bottom: 0;
    }

    .chart-panel {
        min-height: 500px;
    }

    #chartContainer {
        height: 450px;
        min-height: 450px;
    }

    .decade-charts-grid {
        grid-template-columns: 1fr;
    }

    .explanation-overlay {
        width: 85%;
        padding: 24px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 12px;
    }

    .header-banner {
        padding: 12px 14px;
        font-size: 0.85em;
    }

    .nav-button {
        padding: 6px 12px;
        font-size: 0.85em;
    }

    .sidebar {
        flex-direction: column;
    }

    .filter-panel {
        min-width: 100%;
    }

    .chart-panel {
        padding: 16px;
    }

    .chart-title {
        font-size: 1.25rem;
    }

    .explanation-overlay {
        width: 92%;
        padding: 20px 16px;
    }
}