:root {
    /* Core Palette - Dark (Default) */
    --bg-color: #050510;
    --text-color: #e0e0e0;
    --text-muted: #a0a0b0;

    --accent-primary: #00f0ff;
    /* Cyan */
    --accent-secondary: #7000ff;
    /* Purple */
    --accent-tertiary: #ff0055;
    /* Pink/Red */

    --glass-bg: rgba(20, 20, 35, 0.6);
    --glass-border: rgba(255, 255, 255, 0.1);
    --glass-highlight: rgba(255, 255, 255, 0.05);

    --panel-bg: rgba(30, 30, 45, 0.7);

    --canvas-bg: #050510;
    --grid-line: rgba(255, 255, 255, 0.1);
    --grid-axis: rgba(255, 255, 255, 0.4);

    /* Spacing & Sizing */
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;

    --border-radius: 12px;
    --font-family: 'Inter', system-ui, -apple-system, sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
}

[data-theme="light"] {
    --bg-color: #f0f2f5;
    --text-color: #1a1a2e;
    --text-muted: #666677;

    --accent-primary: #0088cc;
    /* Darker Cyan for readability */
    --accent-secondary: #6200ea;
    /* Deep Purple */
    --accent-tertiary: #d50000;
    /* Red */

    --glass-bg: rgba(255, 255, 255, 0.7);
    --glass-border: rgba(0, 0, 0, 0.08);
    --glass-highlight: rgba(255, 255, 255, 0.4);

    --panel-bg: rgba(255, 255, 255, 0.85);

    --canvas-bg: #f8f9fa;
    --grid-line: rgba(0, 0, 0, 0.1);
    --grid-axis: rgba(0, 0, 0, 0.4);
}

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

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: var(--font-family);
    line-height: 1.6;
    height: 100vh;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    transition: background-color 0.3s, color 0.3s;
}

/* Background Gradient - subtle change for light mode could be nice but let's keep it simple or use opacity */
body::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image:
        radial-gradient(circle at 10% 20%, var(--accent-secondary) 0%, transparent 20%),
        radial-gradient(circle at 90% 80%, var(--accent-primary) 0%, transparent 20%);
    opacity: 0.1;
    z-index: -1;
    pointer-events: none;
}

/* Glassmorphism Utilities */
.glass-panel {
    background: var(--glass-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--glass-border);
    border-radius: var(--border-radius);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
    /* Lighter shadow for light mode appropriateness */
}

/* Layout */
.app-container {
    display: flex;
    flex: 1;
    overflow: hidden;
    padding: var(--spacing-md);
    gap: var(--spacing-md);
    max-width: 1600px;
    margin: 0 auto;
    width: 100%;
}

.sidebar {
    width: 320px;
    /* Slightly wider for buttons */
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    overflow-y: auto;
    z-index: 10;
    padding: var(--spacing-md);
    flex-shrink: 0;
}

.main-content {
    flex: 1;
    position: relative;
    border-radius: var(--border-radius);
    overflow: hidden;
    background: var(--canvas-bg);
    display: flex;
    justify-content: center;
    align-items: center;
    border: 1px solid var(--glass-border);
}

canvas {
    display: block;
    width: 100%;
    height: 100%;
}

/* Controls */
h1,
h2,
h3 {
    font-weight: 600;
    letter-spacing: -0.5px;
    color: var(--text-color);
}

h1 {
    font-size: 1.5rem;
    margin-bottom: var(--spacing-sm);
}

h2 {
    font-size: 1.2rem;
    margin-bottom: var(--spacing-sm);
    color: var(--accent-primary);
}

h3 {
    font-size: 0.9rem;
    color: var(--text-color);
    opacity: 0.8;
}

.control-group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
    padding-bottom: var(--spacing-md);
    border-bottom: 1px solid var(--glass-border);
}

.control-group:last-child {
    border-bottom: none;
}

label {
    font-size: 0.85rem;
    color: var(--text-muted);
    display: flex;
    justify-content: space-between;
}

input[type="range"] {
    width: 100%;
    background: transparent;
    -webkit-appearance: none;
    margin: 8px 0;
}

input[type="range"]::-webkit-slider-runnable-track {
    width: 100%;
    height: 4px;
    background: var(--text-muted);
    opacity: 0.3;
    border-radius: 2px;
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    height: 16px;
    width: 16px;
    border-radius: 50%;
    background: var(--accent-primary);
    margin-top: -6px;
    cursor: pointer;
    box-shadow: 0 0 10px var(--accent-primary);
    transition: transform 0.1s;
}

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

button {
    background: rgba(128, 128, 128, 0.1);
    border: 1px solid var(--glass-border);
    color: var(--text-color);
    padding: 8px 16px;
    border-radius: 6px;
    cursor: pointer;
    font-family: var(--font-family);
    font-weight: 500;
    transition: all 0.2s;
    font-size: 0.9rem;
}

button:hover {
    background: rgba(128, 128, 128, 0.2);
    border-color: var(--accent-primary);
}

button.primary {
    background: var(--accent-primary);
    color: var(--bg-color);
    /* Contrast text logic needed, usually black/white depending on accent */
    border: none;
    font-weight: 600;
}

[data-theme="dark"] button.primary {
    color: #000;
}

[data-theme="light"] button.primary {
    color: #fff;
}

button.primary:hover {
    opacity: 0.9;
    box-shadow: 0 0 15px var(--accent-primary);
}

button.active {
    background: var(--accent-secondary);
    color: #fff;
    border-color: var(--accent-secondary);
}

.metrics {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--accent-secondary);
    margin-top: var(--spacing-xs);
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 6px;
}

::-webkit-scrollbar-track {
    background: transparent;
}

::-webkit-scrollbar-thumb {
    background: var(--text-muted);
    opacity: 0.2;
    border-radius: 3px;
}

/* Utility */
.flex-row {
    display: flex;
    gap: var(--spacing-sm);
    align-items: center;
}

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

.hidden {
    display: none !important;
}

/* Navigation Back Link */
.nav-back {
    display: inline-flex;
    align-items: center;
    margin-bottom: var(--spacing-md);
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.9rem;
    transition: color 0.2s;
}

.nav-back:hover {
    color: var(--accent-primary);
}

/* Value Display */
.value-display {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--accent-primary);
}

select {
    width: 100%;
    background: var(--glass-bg);
    color: var(--text-color);
    border: 1px solid var(--glass-border);
    padding: 8px;
    border-radius: 6px;
    outline: none;
}

select option {
    background: var(--bg-color);
    color: var(--text-color);
}

/* Global Settings Area in Sidebar */
#global-settings {
    margin-top: auto;
    /* Push to bottom */
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--glass-border);
    display: flex;
    justify-content: space-between;
}