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

:root {
    --primary-color: #2c3e50;
    --secondary-color: #34495e;
    --accent-color: #3498db;
    --background: #f8f9fa;
    --surface: #ffffff;
    --text-primary: #2c3e50;
    --text-secondary: #7f8c8d;
    --border-color: #e0e0e0;
    --hover-color: #2980b9;
    --selected-color: #16a085;
    --shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    --shadow-hover: 0 4px 12px rgba(0, 0, 0, 0.15);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--background);
    color: var(--text-primary);
    line-height: 1.6;
}

header {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
    padding: 2rem;
    text-align: center;
    box-shadow: var(--shadow);
}

header h1 {
    font-size: 2rem;
    margin-bottom: 0.5rem;
    font-weight: 600;
}

.subtitle {
    font-size: 1rem;
    opacity: 0.9;
}

.top-nav {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    margin-top: 1.5rem;
    flex-wrap: wrap;
}

.nav-btn-wrapper {
    position: relative;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.nav-btn {
    padding: 0.6rem 1.2rem;
    font-size: 0.9rem;
    background: rgba(255, 255, 255, 0.2);
    color: white;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
    font-weight: 500;
    white-space: nowrap;
}

.nav-btn:hover {
    background: rgba(255, 255, 255, 0.3);
    border-color: rgba(255, 255, 255, 0.5);
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

.nav-btn:active {
    transform: translateY(0);
}

.nav-description {
    position: absolute;
    top: calc(100% + 8px);
    left: 50%;
    transform: translateX(-50%);
    padding: 0.75rem 1rem;
    background: rgba(0, 0, 0, 0.95);
    color: white;
    border-radius: 6px;
    font-size: 0.85rem;
    line-height: 1.5;
    white-space: normal;
    width: 320px;
    max-width: 90vw;
    z-index: 1000;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.4);
    pointer-events: none;
    text-align: left;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.2s ease, visibility 0.2s ease, transform 0.2s ease;
    transform: translateX(-50%) translateY(-5px);
}

.nav-btn-wrapper:hover .nav-description {
    opacity: 1;
    visibility: visible;
    transform: translateX(-50%) translateY(0);
}

.nav-description::before {
    content: '';
    position: absolute;
    bottom: 100%;
    left: 50%;
    transform: translateX(-50%);
    border: 6px solid transparent;
    border-bottom-color: rgba(0, 0, 0, 0.9);
    pointer-events: none;
}

.container {
    display: grid;
    grid-template-columns: 280px 1fr;
    gap: 2rem;
    padding: 2rem;
    max-width: 1600px;
    margin: 0 auto;
}

.controls-panel {
    background: var(--surface);
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: var(--shadow);
    height: fit-content;
    position: sticky;
    top: 2rem;
}

.controls-panel h2 {
    font-size: 1.25rem;
    margin-bottom: 1.5rem;
    color: var(--primary-color);
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 0.5rem;
}

.control-group {
    margin-bottom: 1.5rem;
}

.control-group label {
    display: block;
    font-weight: 500;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
    font-size: 0.9rem;
}

#year-slider {
    width: 100%;
    margin-top: 0.5rem;
    cursor: pointer;
}

#year-display {
    font-weight: 600;
    color: var(--accent-color);
}

.toggle-buttons {
    display: flex;
    gap: 0.5rem;
    margin-top: 0.5rem;
}

.toggle-btn {
    flex: 1;
    padding: 0.6rem 1rem;
    border: 2px solid var(--border-color);
    background: var(--surface);
    color: var(--text-primary);
    border-radius: 6px;
    cursor: pointer;
    font-size: 0.85rem;
    transition: all 0.3s ease;
    font-weight: 500;
}

.toggle-btn:hover {
    border-color: var(--accent-color);
    background: #f0f8ff;
}

.toggle-btn.active {
    background: var(--accent-color);
    color: white;
    border-color: var(--accent-color);
}

.state-filter-controls {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
}

.state-filter-controls button {
    flex: 1;
    padding: 0.5rem;
    border: 1px solid var(--border-color);
    background: var(--surface);
    color: var(--text-primary);
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.8rem;
    transition: all 0.2s ease;
}

.state-filter-controls button:hover {
    background: var(--accent-color);
    color: white;
    border-color: var(--accent-color);
}

#state-filter {
    width: 100%;
    border: 2px solid var(--border-color);
    border-radius: 6px;
    padding: 0.5rem;
    font-size: 0.85rem;
    background: var(--surface);
    color: var(--text-primary);
}

#state-filter option {
    padding: 0.3rem;
}

#state-filter option:checked {
    background: var(--accent-color);
    color: white;
}

.visualization-area {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.viz-section {
    background: var(--surface);
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: var(--shadow);
}

.viz-section h2 {
    font-size: 1.25rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 0.5rem;
}

#map-container {
    position: relative;
    width: 100%;
    min-height: 500px;
}

#map-loading {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    z-index: 10;
}

#map-svg {
    width: 100%;
    height: auto;
    display: block;
}

.state-path {
    stroke: white;
    stroke-width: 1;
    cursor: pointer;
    transition: all 0.2s ease;
}

.state-path:hover {
    stroke-width: 2;
    stroke: var(--primary-color);
    filter: brightness(1.1);
}

.state-path.selected {
    stroke: var(--selected-color);
    stroke-width: 2.5;
}

#map-legend {
    position: absolute;
    bottom: 20px;
    right: 20px;
    background: rgba(255, 255, 255, 0.95);
    padding: 1rem;
    border-radius: 6px;
    box-shadow: var(--shadow);
    font-size: 0.85rem;
}

.legend-title {
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

.legend-scale {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.legend-gradient {
    width: 200px;
    height: 20px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
}

.legend-labels {
    display: flex;
    justify-content: space-between;
    margin-top: 0.3rem;
    font-size: 0.75rem;
    color: var(--text-secondary);
}

.charts-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}

#time-series-container,
#bar-chart-container {
    width: 100%;
    min-height: 300px;
}

#time-series-svg,
#bar-chart-svg {
    width: 100%;
    height: 100%;
    display: block;
}

.axis {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.axis-label {
    font-size: 0.9rem;
    font-weight: 500;
    fill: var(--text-primary);
}

.line {
    fill: none;
    stroke-width: 2.5;
    cursor: pointer;
    transition: stroke-width 0.2s ease;
}

.line:hover {
    stroke-width: 3.5;
}

.line-point {
    cursor: pointer;
    transition: r 0.2s ease;
}

.line-point:hover {
    r: 6;
}

.bar {
    cursor: pointer;
    transition: opacity 0.2s ease;
}

.bar:hover {
    opacity: 0.8;
}

.grid-line {
    stroke: var(--border-color);
    stroke-width: 1;
    stroke-dasharray: 3,3;
    opacity: 0.5;
}

.tooltip {
    position: absolute;
    background: rgba(0, 0, 0, 0.9);
    color: white;
    padding: 0.75rem 1rem;
    border-radius: 6px;
    font-size: 0.85rem;
    pointer-events: none;
    opacity: 0;
    transition: opacity 0.2s ease;
    z-index: 1000;
    box-shadow: var(--shadow-hover);
    max-width: 250px;
}

.tooltip.visible {
    opacity: 1;
}

.tooltip-title {
    font-weight: 600;
    margin-bottom: 0.3rem;
    font-size: 0.95rem;
}

.tooltip-item {
    margin: 0.2rem 0;
}

/* Responsive Design */
@media (max-width: 1200px) {
    .charts-container {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .container {
        grid-template-columns: 1fr;
        padding: 1rem;
    }

    .controls-panel {
        position: static;
    }

    header h1 {
        font-size: 1.5rem;
    }

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

    #map-container {
        min-height: 400px;
    }
}

/* Loading state */
.loading {
    text-align: center;
    padding: 3rem;
    color: var(--text-secondary);
}

.loading::after {
    content: '...';
    animation: dots 1.5s steps(4, end) infinite;
}

@keyframes dots {
    0%, 20% { content: '.'; }
    40% { content: '..'; }
    60%, 100% { content: '...'; }
}

/* Accessibility */
button:focus,
input:focus,
select:focus {
    outline: 2px solid var(--accent-color);
    outline-offset: 2px;
}

/* Smooth transitions */
* {
    transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

/* Bar Chart Race visualization */
.bar-race-section {
    margin-top: 3rem;
}

.scroll-viz-controls {
    margin-bottom: 1.5rem;
    display: flex;
    justify-content: center;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
}

.race-controls {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

#speed-slider {
    width: 100px;
    margin: 0 0.5rem;
    cursor: pointer;
}

#bar-race-container {
    position: sticky;
    top: 2rem;
    background: var(--surface);
    padding: 2rem;
    border-radius: 8px;
    box-shadow: var(--shadow);
    min-height: 600px;
}

#bar-race-chart {
    width: 100%;
    min-height: 500px;
}

#bar-race-svg {
    width: 100%;
    height: 100%;
    display: block;
}

.race-bar {
    cursor: pointer;
    transition: opacity 0.2s ease;
}

.race-bar:hover {
    opacity: 0.8;
}

.state-label {
    pointer-events: none;
}

.value-label {
    pointer-events: none;
}

#race-year-indicator {
    text-align: center;
    margin-top: 2rem;
    padding-top: 1.5rem;
    border-top: 2px solid var(--border-color);
}

#current-year-display {
    font-size: 3rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
    line-height: 1;
}

#year-progress {
    font-size: 1rem;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

#total-value-display {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--accent-color);
}