:root {
    /* Color Palette */
    --bg-dark: #0f172a;
    --bg-panel: #1e293b;
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --accent: #3b82f6;
    --accent-hover: #60a5fa;
    --border-color: #334155;
    
    /* Terrain Colors (Islands) */
    --terrain-water: #0ea5e9;
    --terrain-water-hover: #38bdf8;
    --terrain-sand: #fcd34d;
    --terrain-sand-hover: #fbbf24;
    --terrain-grass: #22c55e;
    --terrain-grass-hover: #4ade80;
    --terrain-mountain: #64748b;
    --terrain-mountain-hover: #94a3b8;

    /* Terrain Colors (Floor Plan) */
    --terrain-floor: #d1d5db;
    --terrain-floor-hover: #e5e7eb;
    --terrain-wall: #475569;
    --terrain-wall-hover: #64748b;
    --terrain-empty: #1e293b;
    --terrain-empty-hover: #334155;

    /* Uncollapsed background */
    --terrain-uncollapsed: #0f172a;
    --terrain-uncollapsed-hover: #1e293b;

    --font-heading: 'Outfit', sans-serif;
    --font-body: 'Outfit', sans-serif;
}

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

body {
    background-color: var(--bg-dark);
    color: var(--text-main);
    font-family: var(--font-body);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: flex-start;
    overflow-x: hidden;
}

.app-container {
    max-width: 1400px;
    width: 100%;
    padding: 2rem;
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

/* Navbar */
.navbar {
    width: 100%;
    background-color: var(--bg-panel);
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: flex-end; /* Align elements to the bottom */
    padding: 0.5rem 2rem; /* Slimmer padding */
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

.nav-brand {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--accent);
}

.nav-links {
    list-style: none;
    display: flex;
    gap: 2rem;
}

.nav-links a {
    color: var(--text-muted);
    text-decoration: none;
    font-weight: 400;
    transition: color 0.2s;
}

.nav-links a:hover {
    color: var(--text-main);
}

.nav-links a.active {
    color: var(--accent);
    font-weight: 600;
}

header {
    text-align: center;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--border-color);
}

h1 {
    font-size: 3rem;
    font-weight: 600;
    letter-spacing: -0.05em;
    margin-bottom: 0.5rem;
}

.highlight {
    color: var(--accent);
    background: linear-gradient(135deg, #60a5fa, #3b82f6);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

header p {
    color: var(--text-muted);
    font-size: 1.1rem;
    font-weight: 300;
}

.main-content {
    display: flex;
    gap: 2rem;
    align-items: flex-start;
}

/* Sidebar Styling */
.sidebar {
    flex: 0 0 320px;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.panel {
    background-color: var(--bg-panel);
    border-radius: 12px;
    padding: 1.5rem;
    border: 1px solid var(--border-color);
    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.3);
}

.panel h2 {
    font-size: 1.25rem;
    margin-bottom: 0.5rem;
    font-weight: 600;
}

.panel-desc {
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-bottom: 1.5rem;
    line-height: 1.4;
}

/* Buttons */
.btn {
    width: 100%;
    padding: 0.8rem 1rem;
    border-radius: 8px;
    border: none;
    font-family: inherit;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    margin-bottom: 1rem;
    position: relative;
    overflow: hidden;
}

.primary-btn {
    background-color: var(--accent);
    color: white;
    box-shadow: 0 4px 14px 0 rgba(59, 130, 246, 0.39);
}

.primary-btn:hover {
    background-color: var(--accent-hover);
    transform: translateY(-1px);
}

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

.secondary-btn {
    background-color: transparent;
    color: var(--text-main);
    border: 1px solid var(--border-color);
}

.secondary-btn:hover {
    background-color: rgba(255, 255, 255, 0.05);
}

.status-indicator {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding-top: 1rem;
    border-top: 1px solid var(--border-color);
    font-size: 0.9rem;
    color: var(--text-muted);
}

.status-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background-color: var(--terrain-grass);
    box-shadow: 0 0 8px var(--terrain-grass);
    transition: background-color 0.3s ease;
}

.status-dot.processing {
    background-color: var(--terrain-sand);
    box-shadow: 0 0 8px var(--terrain-sand);
}

/* Terrain Options */
.terrain-options {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.terrain-btn {
    display: flex;
    align-items: center;
    gap: 1rem;
    background: transparent;
    border: 1px solid transparent;
    padding: 0.75rem 1rem;
    border-radius: 8px;
    cursor: pointer;
    color: var(--text-main);
    font-family: inherit;
    font-size: 0.95rem;
    transition: all 0.2s;
}

.terrain-btn:hover {
    background-color: rgba(255, 255, 255, 0.03);
}

.terrain-btn.selected {
    background-color: rgba(255, 255, 255, 0.05);
    border-color: var(--border-color);
    box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.1);
}

.color-swatch {
    width: 20px;
    height: 20px;
    border-radius: 4px;
}

.color-swatch.water { background-color: var(--terrain-water); }
.color-swatch.sand { background-color: var(--terrain-sand); }
.color-swatch.grass { background-color: var(--terrain-grass); }
.color-swatch.mountain { background-color: var(--terrain-mountain); }

.color-swatch.floor { background-color: var(--terrain-floor); }
.color-swatch.wall { background-color: var(--terrain-wall); }
.color-swatch.empty { background-color: var(--terrain-empty); border: 1px solid var(--border-color); }

.color-swatch.erase { 
    background-color: transparent;
    border: 2px dashed var(--text-muted);
}

/* Weight Controls */
.weight-controls {
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
}

.weight-label {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.95rem;
    color: var(--text-main);
}

.weight-name {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.weight-input {
    width: 70px;
    background-color: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    color: var(--text-main);
    padding: 0.4rem 0.5rem;
    border-radius: 6px;
    font-family: inherit;
    font-size: 0.9rem;
    text-align: right;
    transition: border-color 0.2s;
}

.weight-input:focus {
    outline: none;
    border-color: var(--accent);
}

/* Strategy Controls */
.strategy-controls {
    display: flex;
    flex-direction: column;
}

.strategy-select {
    width: 100%;
    background-color: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    color: var(--text-main);
    padding: 0.6rem;
    border-radius: 6px;
    font-family: inherit;
    font-size: 0.95rem;
    cursor: pointer;
    transition: border-color 0.2s;
    appearance: none;
    background-image: url("data:image/svg+xml;charset=UTF-8,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%2394a3b8' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3e%3cpolyline points='6 9 12 15 18 9'%3e%3c/polyline%3e%3c/svg%3e");
    background-repeat: no-repeat;
    background-position: right 0.5rem center;
    background-size: 1em;
}

.strategy-select:focus {
    outline: none;
    border-color: var(--accent);
}

.strategy-select option {
    background-color: var(--bg-panel);
    color: var(--text-main);
}

/* Grid Section */
.grid-section {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: var(--bg-panel);
    border-radius: 12px;
    padding: 2rem;
    border: 1px solid var(--border-color);
    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.3);
}

.grid-wrapper {
    width: 100%;
    aspect-ratio: 1/1;
    max-width: 800px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.grid-container {
    display: grid;
    /* We will use JS to define columns/rows based on sizing, but default 32x32 */
    grid-template-columns: repeat(32, 1fr);
    grid-template-rows: repeat(32, 1fr);
    width: 100%;
    height: 100%;
    background-color: var(--border-color);
    gap: 1px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    overflow: hidden;
}

.tile {
    width: 100%;
    height: 100%;
    background-color: var(--terrain-uncollapsed);
    cursor: pointer;
    transition: background-color 0.15s ease, transform 0.1s ease;
}

.tile:hover {
    background-color: var(--terrain-uncollapsed-hover);
}

/* Rendered Tile States (Islands) */
.tile.water {
    background-color: var(--terrain-water);
}
.tile.water:hover {
    background-color: var(--terrain-water-hover);
}

.tile.sand {
    background-color: var(--terrain-sand);
}
.tile.sand:hover {
    background-color: var(--terrain-sand-hover);
}

.tile.grass {
    background-color: var(--terrain-grass);
}
.tile.grass:hover {
    background-color: var(--terrain-grass-hover);
}

.tile.mountain {
    background-color: var(--terrain-mountain);
}
.tile.mountain:hover {
    background-color: var(--terrain-mountain-hover);
}

/* Rendered Tile States (Floor Plan) */
.tile.floor {
    background-color: var(--terrain-floor);
}
.tile.floor:hover {
    background-color: var(--terrain-floor-hover);
}

.tile.wall {
    background-color: var(--terrain-wall);
}
.tile.wall:hover {
    background-color: var(--terrain-wall-hover);
}

.tile.empty {
    background-color: var(--terrain-empty);
}
.tile.empty:hover {
    background-color: var(--terrain-empty-hover);
}

/* Responsive */
@media (max-width: 1024px) {
    .main-content {
        flex-direction: column;
    }

    .grid-section {
        order: 1;
        width: 100%;
        padding: 1.5rem;
    }
    
    .sidebar {
        order: 2;
        flex: none;
        width: 100%;
        flex-direction: row;
        flex-wrap: wrap;
    }
    
    .panel {
        flex: 1 1 250px;
    }
}

@media (max-width: 768px) {
    .app-container {
        padding: 1rem;
        gap: 1rem;
    }
    
    header h1 {
        font-size: 2.2rem;
    }

    .sidebar {
        flex-direction: column;
        gap: 1rem;
    }

    .terrain-options {
        flex-direction: row;
        flex-wrap: wrap;
    }

    .terrain-btn {
        flex: 1 1 calc(50% - 0.5rem);
        justify-content: center;
    }

    .grid-section {
        padding: 0.5rem;
    }
}