/* CSS Variables */
:root {
    --bg-primary: #0a0a0f;
    --bg-secondary: #12121a;
    --bg-tertiary: #1a1a25;
    --text-primary: #e8e8f0;
    --text-secondary: #a0a0b0;
    --accent-primary: #10b981;
    --accent-secondary: #34d399;
    --accent-tertiary: #6ee7b7;
    --cell-alive: #10b981;
    --cell-dead: #1a1a25;
    --grid-line: #252535;
    --border-radius: 12px;
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.4);
}

/* Reset & Base */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
    line-height: 1.6;
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 20px;
}

/* Header */
.header {
    text-align: center;
    padding: 30px 0;
}

.logo-container {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
    margin-bottom: 10px;
}

.logo {
    width: 60px;
    height: 60px;
    border-radius: var(--border-radius);
}

.header h1 {
    font-size: 2.2rem;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-tertiary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.subtitle {
    color: var(--text-secondary);
    font-size: 1.1rem;
    margin-top: 8px;
}

/* Sections */
section {
    background: var(--bg-secondary);
    border-radius: var(--border-radius);
    padding: 25px;
    margin-bottom: 25px;
    box-shadow: var(--shadow);
}

/* Controls */
.controls {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    align-items: flex-end;
    margin-bottom: 20px;
}

.control-group {
    display: flex;
    align-items: center;
    gap: 10px;
}

.control-group.playback {
    gap: 8px;
}

.control-group label {
    font-size: 0.9rem;
    color: var(--text-secondary);
    font-weight: 500;
}

select, input[type="range"] {
    background: var(--bg-tertiary);
    border: 1px solid var(--grid-line);
    color: var(--text-primary);
    padding: 10px 15px;
    border-radius: 8px;
    font-size: 0.95rem;
    cursor: pointer;
    transition: border-color 0.2s;
}

select:hover, select:focus {
    border-color: var(--accent-primary);
    outline: none;
}

input[type="range"] {
    width: 100px;
    padding: 5px;
    -webkit-appearance: none;
    appearance: none;
    height: 8px;
    border-radius: 4px;
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--accent-primary);
    cursor: pointer;
    transition: transform 0.2s;
}

input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.1);
}

#speed-label {
    font-size: 0.85rem;
    color: var(--text-secondary);
    min-width: 65px;
}

/* Buttons */
.btn {
    padding: 10px 18px;
    border: none;
    border-radius: 8px;
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
}

.btn-primary {
    background: linear-gradient(135deg, var(--accent-primary), #059669);
    color: white;
    min-width: 50px;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(16, 185, 129, 0.4);
}

.btn-secondary {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--grid-line);
}

.btn-secondary:hover {
    background: var(--grid-line);
}

/* Stats */
.stats {
    display: flex;
    gap: 30px;
    margin-bottom: 15px;
}

.stat {
    display: flex;
    align-items: center;
    gap: 8px;
}

.stat-label {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.stat-value {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--accent-secondary);
    min-width: 50px;
}

/* Status Indicator */
.status-indicator {
    display: none;
}

.status-indicator.visible {
    display: flex;
}

.status-badge {
    padding: 6px 14px;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 600;
    animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
    from { opacity: 0; transform: scale(0.9); }
    to { opacity: 1; transform: scale(1); }
}

.status-badge.stable {
    background: rgba(16, 185, 129, 0.2);
    color: #10b981;
    border: 1px solid rgba(16, 185, 129, 0.4);
}

.status-badge.oscillating {
    background: rgba(251, 191, 36, 0.2);
    color: #fbbf24;
    border: 1px solid rgba(251, 191, 36, 0.4);
}

.status-badge.extinct {
    background: rgba(239, 68, 68, 0.2);
    color: #ef4444;
    border: 1px solid rgba(239, 68, 68, 0.4);
}

/* Canvas Container */
.canvas-container {
    position: relative;
    background: var(--bg-primary);
    border-radius: var(--border-radius);
    overflow: hidden;
    display: flex;
    justify-content: center;
    align-items: center;
}

canvas {
    display: block;
    cursor: crosshair;
}

.hint {
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.85rem;
    margin-top: 15px;
}

/* Explanation Section */
.explanation-section {
    background: var(--bg-secondary);
}

.explanation-section h2 {
    font-size: 1.8rem;
    margin-bottom: 25px;
    color: var(--accent-secondary);
    text-align: center;
}

.explanation-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
}

.explanation-card {
    background: var(--bg-tertiary);
    padding: 20px;
    border-radius: var(--border-radius);
    border-left: 3px solid var(--accent-primary);
}

.explanation-card h3 {
    font-size: 1.1rem;
    margin-bottom: 12px;
    color: var(--accent-tertiary);
}

.explanation-card p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: 10px;
}

.explanation-card p:last-child {
    margin-bottom: 0;
}

/* Rules List */
.explanation-card.rules ul {
    list-style: none;
}

.explanation-card.rules li {
    display: flex;
    align-items: flex-start;
    gap: 10px;
    margin-bottom: 10px;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.rule-icon {
    font-size: 1rem;
    min-width: 20px;
    text-align: center;
}

.rule-icon.death {
    color: #ef4444;
}

.rule-icon.life {
    color: var(--accent-primary);
}

.rule-icon.birth {
    color: #fbbf24;
}

/* Pattern Types */
.pattern-types {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.pattern-type {
    display: flex;
    align-items: center;
    gap: 10px;
    flex-wrap: wrap;
}

.pattern-icon {
    font-size: 1.2rem;
    color: var(--accent-primary);
    min-width: 25px;
}

.pattern-type strong {
    color: var(--text-primary);
    margin-right: 5px;
}

.pattern-type p {
    color: var(--text-secondary);
    font-size: 0.85rem;
    margin: 0;
    flex-basis: 100%;
    padding-left: 35px;
}

.creator {
    font-style: italic;
    color: var(--text-secondary);
    margin-top: 15px;
    padding-top: 10px;
    border-top: 1px solid var(--grid-line);
}

/* Footer */
.footer {
    text-align: center;
    padding: 20px;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Responsive */
@media (max-width: 768px) {
    .header h1 {
        font-size: 1.6rem;
    }

    .logo-container {
        flex-direction: column;
        gap: 10px;
    }

    .controls {
        flex-direction: column;
        align-items: stretch;
    }

    .control-group {
        justify-content: space-between;
    }

    .control-group.playback {
        justify-content: center;
    }

    select {
        flex: 1;
    }

    input[type="range"] {
        flex: 1;
    }

    .stats {
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 10px;
    }

    section {
        padding: 15px;
    }

    .btn {
        padding: 10px 14px;
        font-size: 0.9rem;
    }
}