:root {
    --bg-primary: #0a0e1a;
    --bg-secondary: #111827;
    --bg-tertiary: #1f2937;
    --bg-card: #1a2236;
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    --accent-cyan: #06b6d4;
    --accent-magenta: #d946ef;
    --accent-blue: #3b82f6;
    --accent-green: #10b981;
    --accent-yellow: #f59e0b;
    --accent-red: #ef4444;
    --gradient-start: #06b6d4;
    --gradient-end: #d946ef;
    --border: #1e3a5f;
    --border-light: #2d4a6f;
    --glow-cyan: rgba(6, 182, 212, 0.4);
    --glow-magenta: rgba(217, 70, 239, 0.4);
    --shadow: rgba(0, 0, 0, 0.4);
}

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

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

.container {
    max-width: 1800px;
    margin: 0 auto;
    padding: 16px;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

header {
    text-align: center;
    padding: 24px 0 16px;
    border-bottom: 1px solid var(--border);
    margin-bottom: 16px;
}

header h1 {
    font-size: 2.4rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 8px;
    letter-spacing: -0.5px;
}

.subtitle {
    color: var(--text-secondary);
    font-size: 1.05rem;
    max-width: 600px;
    margin: 0 auto;
}

.main-content {
    display: grid;
    grid-template-columns: 300px 1fr;
    gap: 16px;
    flex: 1;
}

/* ========== Controls Panel ========== */
.controls-panel {
    background: var(--bg-secondary);
    border-radius: 12px;
    padding: 16px;
    height: fit-content;
    position: sticky;
    top: 16px;
    overflow-y: auto;
    max-height: calc(100vh - 32px);
    border: 1px solid var(--border);
}

.controls-panel::-webkit-scrollbar {
    width: 6px;
}

.controls-panel::-webkit-scrollbar-track {
    background: transparent;
}

.controls-panel::-webkit-scrollbar-thumb {
    background: var(--border-light);
    border-radius: 3px;
}

.control-section {
    margin-bottom: 16px;
    padding-bottom: 16px;
    border-bottom: 1px solid var(--border);
}

.control-section:last-child {
    border-bottom: none;
    margin-bottom: 0;
    padding-bottom: 0;
}

.control-section h2 {
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 1.2px;
    color: var(--text-secondary);
    margin-bottom: 12px;
    font-weight: 600;
}

.control-group {
    margin-bottom: 10px;
}

.control-group label {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.88rem;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.value-display {
    font-family: 'SF Mono', 'Fira Code', 'Consolas', monospace;
    color: var(--accent-cyan);
    font-size: 0.85rem;
    font-weight: 600;
    min-width: 60px;
    text-align: right;
}

input[type="range"] {
    width: 100%;
    height: 6px;
    -webkit-appearance: none;
    appearance: none;
    background: var(--bg-tertiary);
    border-radius: 3px;
    outline: none;
    cursor: pointer;
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: var(--accent-cyan);
    cursor: pointer;
    box-shadow: 0 0 6px var(--glow-cyan);
    transition: transform 0.15s;
}

input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.2);
}

input[type="range"]::-moz-range-thumb {
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: var(--accent-cyan);
    cursor: pointer;
    border: none;
    box-shadow: 0 0 6px var(--glow-cyan);
}

input[type="number"] {
    width: 80px;
    padding: 4px 8px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    border-radius: 6px;
    color: var(--text-primary);
    font-size: 0.85rem;
    font-family: 'SF Mono', 'Fira Code', monospace;
    outline: none;
    transition: border-color 0.2s;
}

input[type="number"]:focus {
    border-color: var(--accent-cyan);
}

/* ========== Buttons ========== */
.view-buttons {
    display: flex;
    gap: 4px;
    flex-wrap: wrap;
}

.view-btn,
.proj-btn {
    flex: 1;
    min-width: 60px;
    padding: 6px 8px;
    font-size: 0.78rem;
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    border-radius: 6px;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all 0.2s;
    white-space: nowrap;
}

.view-btn:hover,
.proj-btn:hover {
    border-color: var(--accent-cyan);
    color: var(--text-primary);
}

.view-btn.active,
.proj-btn.active {
    background: linear-gradient(135deg, rgba(6, 182, 212, 0.15), rgba(217, 70, 239, 0.15));
    border-color: var(--accent-cyan);
    color: var(--text-primary);
    box-shadow: 0 0 8px rgba(6, 182, 212, 0.2);
}

.action-buttons {
    display: flex;
    gap: 6px;
}

.primary-btn,
.secondary-btn,
.accent-btn {
    flex: 1;
    padding: 8px 12px;
    font-size: 0.85rem;
    border-radius: 8px;
    cursor: pointer;
    border: none;
    font-weight: 600;
    transition: all 0.2s;
}

.primary-btn {
    background: linear-gradient(135deg, var(--accent-cyan), var(--accent-blue));
    color: #fff;
    box-shadow: 0 2px 8px rgba(6, 182, 212, 0.3);
}

.primary-btn:hover {
    box-shadow: 0 4px 16px rgba(6, 182, 212, 0.5);
    transform: translateY(-1px);
}

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

.secondary-btn:hover {
    border-color: var(--accent-cyan);
}

.accent-btn {
    width: 100%;
    margin-top: 8px;
    background: linear-gradient(135deg, var(--accent-magenta), var(--accent-cyan));
    color: #fff;
    font-size: 0.82rem;
    padding: 7px 10px;
}

.accent-btn:hover {
    box-shadow: 0 2px 12px rgba(217, 70, 239, 0.4);
    transform: translateY(-1px);
}

.preset-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: 4px;
}

.preset-btn {
    flex: 1;
    min-width: 120px;
    padding: 6px 8px;
    font-size: 0.78rem;
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    border-radius: 6px;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all 0.2s;
}

.preset-btn:hover {
    border-color: var(--accent-magenta);
    color: var(--text-primary);
    background: rgba(217, 70, 239, 0.1);
}

/* Initial Conditions */
.ic-row {
    margin-bottom: 6px;
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.ic-row label {
    display: flex;
    align-items: center;
    gap: 8px;
}

/* ========== Metrics ========== */
.metrics .metric-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 5px 0;
    font-size: 0.85rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.04);
}

.metrics .metric-item:last-child {
    border-bottom: none;
}

.metrics .metric-item span:first-child {
    color: var(--text-secondary);
}

.metrics .metric-item span:last-child {
    font-family: 'SF Mono', 'Fira Code', monospace;
    color: var(--accent-cyan);
    font-weight: 600;
}

#state-value.chaotic {
    color: var(--accent-red) !important;
    text-shadow: 0 0 8px rgba(239, 68, 68, 0.5);
}

#state-value.periodic {
    color: var(--accent-green) !important;
}

#state-value.transient {
    color: var(--accent-yellow) !important;
}

#lyapunov-value.positive {
    color: var(--accent-red) !important;
    text-shadow: 0 0 8px rgba(239, 68, 68, 0.4);
}

#lyapunov-value.negative {
    color: var(--accent-green) !important;
}

/* ========== Main Canvas ========== */
.visualization-panel {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.canvas-container {
    position: relative;
    background: var(--bg-primary);
    border-radius: 12px;
    border: 1px solid var(--border);
    overflow: hidden;
    aspect-ratio: 4 / 3;
    box-shadow:
        0 0 30px rgba(6, 182, 212, 0.05),
        0 0 60px rgba(217, 70, 239, 0.03),
        inset 0 0 60px rgba(0, 0, 0, 0.3);
}

.canvas-container canvas {
    width: 100%;
    height: 100%;
    display: block;
    cursor: grab;
}

.canvas-container canvas:active {
    cursor: grabbing;
}

.canvas-hint {
    position: absolute;
    bottom: 12px;
    right: 12px;
    font-size: 0.75rem;
    color: var(--text-muted);
    background: rgba(0, 0, 0, 0.5);
    padding: 4px 10px;
    border-radius: 4px;
    pointer-events: none;
    opacity: 0.7;
}

/* ========== Education Section ========== */
.education-section {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 12px;
}

.edu-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 16px;
    transition: border-color 0.3s;
}

.edu-card:hover {
    border-color: var(--border-light);
}

.edu-card h3 {
    font-size: 0.95rem;
    color: var(--accent-cyan);
    margin-bottom: 8px;
    font-weight: 600;
}

.edu-card p {
    font-size: 0.85rem;
    color: var(--text-secondary);
    line-height: 1.65;
}

/* ========== Formulas Section ========== */
.formulas-section {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 20px;
}

.formulas-section h3 {
    font-size: 1.1rem;
    color: var(--accent-magenta);
    margin-bottom: 16px;
    font-weight: 600;
}

.formula-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 12px;
}

.formula-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 14px;
}

.formula-card h4 {
    font-size: 0.82rem;
    text-transform: uppercase;
    letter-spacing: 0.8px;
    color: var(--text-secondary);
    margin-bottom: 8px;
    font-weight: 600;
}

.formula {
    font-family: 'SF Mono', 'Fira Code', 'Consolas', monospace;
    font-size: 0.9rem;
    color: var(--accent-cyan);
    padding: 3px 0;
    line-height: 1.8;
}

/* ========== Footer ========== */
footer {
    text-align: center;
    padding: 20px 0 12px;
    border-top: 1px solid var(--border);
    margin-top: 16px;
    color: var(--text-muted);
    font-size: 0.85rem;
}

/* ========== Responsive ========== */
@media (max-width: 1024px) {
    .main-content {
        grid-template-columns: 280px 1fr;
    }

    header h1 {
        font-size: 2rem;
    }
}

@media (max-width: 860px) {
    .main-content {
        grid-template-columns: 1fr;
    }

    .controls-panel {
        position: static;
        max-height: none;
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
        gap: 0 16px;
    }

    .control-section {
        border-bottom: none;
        padding-bottom: 0;
    }

    .canvas-container {
        aspect-ratio: 16 / 10;
    }
}

@media (max-width: 640px) {
    .container {
        padding: 10px;
    }

    header h1 {
        font-size: 1.6rem;
    }

    .subtitle {
        font-size: 0.9rem;
    }

    .controls-panel {
        display: flex;
        flex-direction: column;
        gap: 0;
    }

    .education-section {
        grid-template-columns: 1fr;
    }

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

    .action-buttons {
        flex-wrap: wrap;
    }

    .view-buttons {
        flex-wrap: wrap;
    }

    .canvas-container {
        aspect-ratio: 1 / 1;
    }
}