:root {
    --font-heading: 'Merriweather', serif;
    --font-body: 'Inter', sans-serif;
    --font-mono: 'Roboto Mono', monospace;
    
    --color-bg: #F8F9FA;
    --color-surface: #FFFFFF;
    --color-text-primary: #1A202C;
    --color-text-secondary: #4A5568;
    --color-text-muted: #718096;
    --color-border: #E2E8F0;
    --color-accent: #2B6CB0;
    --color-accent-hover: #2C5282;
    --radius: 6px;
    --header-height: 60px;
    --footer-height: 30px;
}

* {
    box-sizing: border-box;
}

body {
    background-color: var(--color-bg);
    color: var(--color-text-primary);
    font-family: var(--font-body);
    font-size: 14px;
    margin: 0;
    padding: 0;
    height: 100vh;
    overflow: hidden; /* Prevent body scroll */
}

.app-container {
    display: flex;
    flex-direction: column;
    height: 100vh;
    width: 100vw;
}

/* --- Header --- */
.app-header {
    height: var(--header-height);
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 20px;
    flex-shrink: 0;
    position: relative; /* For absolute centering of nav */
}

.header-left {
    display: flex;
    align-items: center;
    gap: 20px;
}

.app-title {
    font-family: var(--font-heading);
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--color-text-primary);
    margin: 0;
    white-space: nowrap;
}

/* Tabs - Centered Segmented Control */
.tab-navigation {
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    background: var(--color-surface);
    border: 2px solid var(--color-accent); /* Stark outline */
    border-radius: 6px;
    overflow: hidden;
}

.tab-btn {
    font-family: var(--font-body);
    font-size: 0.85rem;
    padding: 6px 16px;
    background: transparent;
    border: none;
    border-right: 1px solid var(--color-accent); /* Divider */
    border-radius: 0;
    color: var(--color-accent);
    cursor: pointer;
    transition: all 0.2s;
    font-weight: 500;
}

.tab-btn:last-child {
    border-right: none;
}

.tab-btn:hover {
    background-color: rgba(43, 108, 176, 0.1);
}

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

.tab-home {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 6px 10px;
    text-decoration: none;
}

.tab-home svg {
    display: block;
}

/* Header Controls */
.header-controls {
    display: flex;
    align-items: center;
}

.control-group.hidden {
    display: none;
}

.control-wrapper {
    display: flex;
    align-items: center;
    gap: 0;
    background: var(--color-bg);
    border: 2px solid var(--color-accent); /* Stark outline */
    border-radius: 6px;
    padding: 0;
    overflow: hidden;
}

.control-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 6px 8px;
    background: rgba(43, 108, 176, 0.1);
    color: var(--color-accent);
    border-right: 1px solid var(--color-accent);
    height: 100%;
}

.playback-inner {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 4px 10px;
}

.component-select-clean {
    padding: 6px 10px;
    border: none;
    font-family: var(--font-body);
    font-size: 0.85rem;
    color: var(--color-text-primary);
    background-color: transparent;
    min-width: 200px;
    outline: none;
}

.icon-btn {
    background: none;
    border: none;
    cursor: pointer;
    font-size: 0.9rem;
    color: var(--color-accent);
    padding: 0;
    display: flex;
    align-items: center;
}

.icon-btn:hover {
    color: var(--color-accent-hover);
}

#year-slider {
    width: 120px;
    accent-color: var(--color-accent);
}

.year-badge {
    font-family: var(--font-mono);
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--color-text-primary);
    min-width: 40px;
    text-align: right;
}

/* --- Main Content --- */
.app-content {
    flex: 1;
    overflow: hidden; /* Content fits exactly */
    position: relative;
    padding: 16px;
}

.tab-pane {
    display: none;
    height: 100%;
    width: 100%;
}

.tab-pane.active {
    display: block;
}

/* Layouts */
.pane-layout {
    display: grid;
    grid-template-columns: 1fr 280px; /* Sidebar fixed width */
    gap: 16px;
    height: 100%;
}

.pane-layout.full {
    grid-template-columns: 1fr;
}

/* Charts */
.chart-container {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 16px;
    height: 100%;
    display: flex;
    flex-direction: column;
}

.chart-wrapper {
    flex: 1;
    width: 100%;
    min-height: 0; /* Important for flex child to shrink */
    position: relative;
}

.chart-header-inline {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 10px;
    padding-bottom: 10px;
    border-bottom: 1px solid var(--color-border);
}

.chart-header-inline h2 {
    font-size: 1rem;
    margin: 0;
    font-family: var(--font-heading);
}

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

/* Sidebar */
.sidebar {
    display: flex;
    flex-direction: column;
    gap: 16px;
    height: 100%;
    min-height: 0;
}

.card {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 12px;
}

.summary-card {
    flex-shrink: 0;
}

.summary-card h3, .legend-card h3 {
    font-size: 0.75rem;
    text-transform: uppercase;
    color: var(--color-text-muted);
    margin: 0 0 10px 0;
    border-bottom: 1px solid var(--color-border);
    padding-bottom: 5px;
}

.stat-compact {
    display: flex;
    justify-content: space-between;
    margin-bottom: 6px;
    font-size: 0.85rem;
}

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

.stat-compact .highlight {
    color: var(--color-accent);
}

.legend-card {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-height: 0;
}

.scrollable-legend {
    overflow-y: auto;
    flex: 1;
    padding-right: 4px;
}

/* Legend Items */
.legend-item {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.8rem;
    padding: 4px 6px;
    border-radius: 4px;
    cursor: pointer;
    transition: background 0.1s;
    margin-bottom: 2px;
}

.legend-item:hover {
    background-color: var(--color-bg);
}

.legend-item.disabled {
    opacity: 0.5;
    text-decoration: line-through;
}

.legend-color {
    width: 12px;
    height: 12px;
    border-radius: 2px;
    flex-shrink: 0;
}

/* Tooltip */
.tooltip {
    position: absolute;
    background: rgba(26, 32, 44, 0.95);
    backdrop-filter: blur(4px);
    color: white;
    padding: 8px 12px;
    border-radius: 4px;
    font-family: var(--font-body);
    font-size: 0.8rem;
    pointer-events: none;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    z-index: 1000;
    border: 1px solid rgba(255,255,255,0.1);
}

.tooltip h4 {
    margin: 0 0 4px 0;
    font-size: 0.85rem;
    border-bottom: 1px solid rgba(255,255,255,0.2);
    padding-bottom: 2px;
}

/* --- Footer --- */
.app-footer {
    height: var(--footer-height);
    background: var(--color-surface);
    border-top: 1px solid var(--color-border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 20px;
    font-size: 0.7rem;
    color: var(--color-text-muted);
    flex-shrink: 0;
}

.app-footer a {
    color: var(--color-accent);
    text-decoration: none;
    font-weight: 600;
    transition: color 0.2s;
}

.app-footer a:hover {
    color: var(--color-accent-hover);
}

/* Mobile Toggles */
.mobile-only {
    display: none;
}

.icon-btn-box {
    background: var(--color-bg);
    border: 2px solid var(--color-accent);
    border-radius: 6px;
    color: var(--color-accent);
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    padding: 0;
    margin-right: 8px; /* Space between toggles */
    transition: all 0.2s;
}

.icon-btn-box:hover, .icon-btn-box.active {
    background: var(--color-accent);
    color: white;
}

/* Close Button (Hidden by default) */
.close-card-btn {
    display: none;
    position: absolute;
    top: 8px;
    right: 8px;
    background: none;
    border: none;
    color: var(--color-text-muted);
    cursor: pointer;
    padding: 4px;
    z-index: 10;
}

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

/* Tab Text Visibility */
.desktop-text { display: inline; }
.mobile-text { display: none; }

/* Responsive */
@media (max-width: 1024px) {
    .app-header {
        height: auto;
        flex-wrap: wrap;
        padding: 10px 20px;
        gap: 10px;
        justify-content: center; /* Center items when wrapped */
    }

    .header-left {
        order: 1;
        margin-right: auto; /* Push others to right if space permits */
    }

    .tab-navigation {
        position: static;
        transform: none;
        order: 3; /* Move to new line if needed, or middle */
        margin: 5px auto; /* Center it */
        width: auto; /* Let it shrink/grow naturally */
        max-width: 100%;
    }

    .header-controls {
        order: 2;
        margin-left: auto;
    }

    /* Force new line for tabs if screen is too narrow but not yet mobile */
    .header-left, .header-controls {
        flex-shrink: 0;
    }

    .pane-layout {
        grid-template-columns: 1fr;
        grid-template-rows: 1fr auto;
    }
    .sidebar {
        height: auto;
        flex-direction: row;
        justify-content: space-between; /* Add spacing */
    }
    .summary-card {
        min-width: 200px; /* Ensure reasonable width */
    }
    .scrollable-legend {
        max-height: 150px; /* Slightly larger on tablet */
    }
}

@media (max-width: 768px) {
    /* Header Stacked Layout */
    .app-header {
        flex-direction: column;
        height: auto;
        padding: 10px 16px;
        gap: 10px;
        align-items: stretch; /* Stretch items to full width */
    }

    /* Tab Text Switching */
    .desktop-text { display: none; }
    .mobile-text { display: inline; }

    .header-left {
        width: 100%;
        justify-content: center;
        margin-bottom: 5px;
        margin-right: 0; /* Reset from tablet override */
        padding-top: 10px; /* Add space from top of screen */
    }

    .app-title {
        white-space: nowrap; /* Prevent text wrapping */
        text-align: center;
        line-height: 1.2;
        font-size: 0.9rem; /* Reduce font size to fit */
        overflow: hidden;
        text-overflow: ellipsis; /* Add ellipsis if it still overflows */
        width: 100%;
        display: block;
    }

    .tab-navigation {
        position: static;
        transform: none;
        width: 100%;
        margin: 5px 0;
        order: 2; /* Reset order for mobile stack */
        display: flex; /* Ensure flex context */
    }
    
    .tab-btn {
        flex: 1 1 0px; /* Force even distribution with 0 basis */
        text-align: center;
        padding: 8px 4px;
        font-size: 0.8rem;
        white-space: nowrap; /* Prevent tab text wrap */
        width: 100%; /* Ensure width is respected in flex */
        min-width: 0; /* Allow shrinking below content size if needed */
    }

    .tab-home {
        flex: 0 0 auto;
        width: auto;
        padding: 8px 12px;
    }
    
    .header-controls {
        width: 100%;
        flex-wrap: nowrap;
        gap: 8px;
    }

    /* Mobile Toggles */
    .mobile-only {
        display: flex;
        align-items: center;
        flex: 0 0 auto; /* Don't grow */
    }
    
    #mobile-toggles {
        gap: 8px;
    }

    #play-year-btn {
        margin-right: 0 !important;
        flex: 0 0 auto;
    }

    /* Adjust control wrapper to take remaining space or full row */
    .control-group:not(.mobile-only) {
        flex: 1 1 auto;
        min-width: 0;
    }

    /* Timeline Controls (Filter) - Allow to flow naturally */
    #timeline-controls {
        flex: 1 1 auto;
        min-width: 0;
    }
    
    .control-wrapper {
        width: 100%;
        flex: 1 1 auto;
        min-width: 0;
    }
    
    .component-select-clean, #year-select {
        width: 100%;
        flex: 1 1 auto;
        min-width: 0;
    }

    .icon-btn-box {
        margin-right: 0;
    }

    .component-select-clean {
        -webkit-appearance: none;
        appearance: none;
        background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='18' height='18' viewBox='0 0 24 24' fill='none' stroke='%234A5568' stroke-width='2.5' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'/%3E%3C/svg%3E");
        background-repeat: no-repeat;
        background-position: right 14px center;
        background-size: 16px 16px;
        padding-right: 44px;
    }

    /* Content Padding Reset for Mobile */
    .app-content {
        padding: 10px 0 0 0; /* Remove side padding */
    }

    .chart-container {
        border-left: none;
        border-right: none;
        border-radius: 0;
        padding: 10px 0; /* Vertical padding only */
    }

    .chart-header-inline {
        padding: 0 16px 10px 16px; /* Restore padding for text */
        flex-direction: column;
        align-items: flex-start;
        gap: 4px;
    }

    /* Sidebar Stacked Layout for Mobile */
    .sidebar {
        display: block; /* Restore block to allow fixed children */
        height: 0;
        overflow: visible; /* Allow popups to overflow */
        padding: 0;
        margin: 0;
        width: 0; /* Remove width influence */
        position: relative; /* Context for children if needed */
        flex-direction: column; /* Reset flex */
        gap: 0; /* Reset gap */
    }
    
    /* Hide Cards by default */
    .summary-card, .legend-card {
        display: none;
        width: auto;
    }
    
    /* Popup State */
    .card.popup-active {
        display: block;
        position: fixed;
        top: 50%;
        left: 50%;
        transform: translate(-50%, -50%);
        z-index: 2000;
        width: 90vw;
        max-width: 350px;
        box-shadow: 0 10px 25px rgba(0,0,0,0.2);
        border: 1px solid var(--color-accent);
        max-height: 80vh;
        overflow-y: auto;
        background: var(--color-surface);
    }
    
    .close-card-btn {
        display: block;
    }
    
    /* Backdrop for popup */
    .popup-backdrop {
        position: fixed;
        top: 0;
        left: 0;
        width: 100vw;
        height: 100vh;
        background: rgba(0,0,0,0.5);
        z-index: 1999;
        display: none;
    }
    
    .popup-backdrop.active {
        display: block;
    }

    /* Footer Stacked Layout */
    .app-footer {
        height: auto;
        flex-direction: column;
        gap: 2px; /* Reduce gap from 8px */
        padding: 8px 16px; /* Slightly tighter padding */
        text-align: center;
    }
    
    .footer-right {
        order: 1; /* Right text on top */
        margin-bottom: 0; /* Remove bottom margin */
    }
    
    .footer-left {
        order: 2; /* Left text below */
    }
}