:root {
    --primary-color: #6366f1;
    --secondary-color: #8b5cf6;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --danger-color: #ef4444;
    --dark-bg: #1e1e2e;
    --card-bg: #2a2a3e;
    --text-primary: #e0e0e0;
    --text-secondary: #a0a0b0;
    --border-color: #3a3a4e;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #1e1e2e 0%, #2d1b4e 100%);
    color: var(--text-primary);
    min-height: 100vh;
    line-height: 1.6;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 2rem;
}

header {
    text-align: center;
    margin-bottom: 3rem;
    padding: 2rem 0;
}

header h1 {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
    color: #e0e0e0; /* Bright visible color */
}

.subtitle {
    font-size: 1.2rem;
    color: var(--text-secondary);
}

.grid-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

.card {
    background: var(--card-bg);
    border: 2px solid var(--border-color);
    border-radius: 16px;
    padding: 2rem;
    cursor: pointer;
    transition: all 0.3s ease;
    text-align: center;
}

.card:hover {
    transform: translateY(-8px);
    border-color: var(--primary-color);
    box-shadow: 0 12px 24px rgba(99, 102, 241, 0.3);
}

.card-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
}

.card h2 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.card p {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

.explore-btn {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
    border: none;
    padding: 0.75rem 2rem;
    border-radius: 8px;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
}

.explore-btn:hover {
    transform: scale(1.05);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.5);
}

footer {
    text-align: center;
    padding: 2rem 0;
    color: var(--text-secondary);
    border-top: 1px solid var(--border-color);
}

/* Subpage Styles */
.subpage-container {
    max-width: 1600px;
    margin: 0 auto;
    padding: 2rem;
}

.back-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background: var(--card-bg);
    color: var(--text-primary);
    border: 2px solid var(--border-color);
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    text-decoration: none;
    margin-bottom: 2rem;
    transition: all 0.3s ease;
}

.back-btn:hover {
    border-color: var(--primary-color);
    transform: translateX(-4px);
}

.content-wrapper {
    display: grid;
    grid-template-columns: 1fr 400px;
    gap: 2rem;
    margin-bottom: 2rem;
}

.main-content {
    background: var(--card-bg);
    border: 2px solid var(--border-color);
    border-radius: 16px;
    padding: 2rem;
}

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

.info-panel {
    background: var(--card-bg);
    border: 2px solid var(--border-color);
    border-radius: 16px;
    padding: 1.5rem;
}

.info-panel h3 {
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.canvas-container {
    background: #1a1a2e;
    border-radius: 8px;
    padding: 1rem;
    margin-bottom: 1rem;
    display: flex;
    justify-content: center;
    align-items: center;
}

#environment-canvas {
    border: 2px solid var(--border-color);
    border-radius: 4px;
}

.algorithm-tabs {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
}

.tab-btn {
    flex: 1;
    min-width: 120px;
    padding: 0.75rem 1rem;
    background: var(--dark-bg);
    color: var(--text-secondary);
    border: 2px solid var(--border-color);
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 0.9rem;
}

.tab-btn:hover {
    border-color: var(--primary-color);
}

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

.tab-content {
    display: none;
}

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

.controls {
    display: flex;
    gap: 1rem;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
}

.control-btn {
    padding: 0.75rem 1.5rem;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 1rem;
}

.control-btn:hover {
    background: var(--secondary-color);
    transform: scale(1.05);
}

.control-btn:disabled {
    background: var(--border-color);
    cursor: not-allowed;
    transform: none;
}

.control-btn.reset {
    background: var(--warning-color);
}

.control-btn.stop {
    background: var(--danger-color);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1rem;
    margin-top: 1rem;
}

.stat-item {
    background: var(--dark-bg);
    padding: 1rem;
    border-radius: 8px;
    border: 1px solid var(--border-color);
}

.stat-label {
    color: var(--text-secondary);
    font-size: 0.85rem;
    margin-bottom: 0.25rem;
}

.stat-value {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
}

.chart-container {
    background: var(--dark-bg);
    border-radius: 8px;
    padding: 1rem;
    margin-top: 1rem;
    height: 300px;
}

.algorithm-description {
    background: var(--dark-bg);
    padding: 1.5rem;
    border-radius: 8px;
    margin-top: 1rem;
    border-left: 4px solid var(--primary-color);
}

.algorithm-description h4 {
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.slider-control {
    margin-bottom: 1rem;
}

.slider-control label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
}

.slider-control input[type="range"] {
    width: 100%;
    height: 6px;
    border-radius: 3px;
    background: var(--dark-bg);
    outline: none;
}

.slider-control input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
}

.slider-control input[type="range"]::-moz-range-thumb {
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
    border: none;
}

@media (max-width: 1200px) {
    .content-wrapper {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    header h1 {
        font-size: 1.8rem;
    }

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

    .algorithm-tabs {
        flex-direction: column;
    }

    .tab-btn {
        min-width: 100%;
    }
}