:root {
    --primary: #6366F1;
    --bg-main: #0F1219;

    --glass-bg: rgba(20, 25, 35, 0.4);
    --glass-border: rgba(255, 255, 255, 0.08);

    --text-main: #F8FAFC;
    --text-muted: #94A3B8;

    --font-sans: 'Inter', system-ui, sans-serif;
    --radius: 12px;
    --radius-sm: 8px;
}

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

body {
    font-family: var(--font-sans);
    background: var(--bg-main);
    color: var(--text-main);
    height: 100vh;
    overflow: hidden;
    user-select: none;
}

/* Canvas Layer */
#viz-canvas {
    position: absolute;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: 1;
    /* Add subtle grain for premium aesthetics */
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noiseFilter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noiseFilter)' opacity='0.03'/%3E%3C/svg%3E");
}

/* UI Layer overlay */
.ui-layer {
    position: relative;
    z-index: 10;
    height: 100vh;
    display: flex;
    flex-direction: column;
    pointer-events: none;
    /* Let clicks pass through empty areas */
}

.glass {
    background: var(--glass-bg);
    backdrop-filter: blur(24px);
    -webkit-backdrop-filter: blur(24px);
    border: 1px solid var(--glass-border);
}

/* Header */
.top-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 2rem;
    pointer-events: auto;
    border-bottom: 1px solid var(--glass-border);
}

.brand {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.logo {
    color: var(--primary);
    display: flex;
    align-items: center;
    justify-content: center;
}

.logo svg {
    width: 24px;
    height: 24px;
}

.brand h1 {
    font-size: 1.125rem;
    font-weight: 600;
    letter-spacing: -0.02em;
}

.actions {
    display: flex;
    gap: 0.5rem;
}

/* Dashboard Panel */
.dashboard-wrapper {
    flex: 1;
    display: flex;
    align-items: center;
    padding: 2rem;
    max-width: 400px;
}

.dashboard-panel {
    width: 100%;
    border-radius: var(--radius);
    padding: 1.5rem;
    pointer-events: auto;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    transition: opacity 0.3s;
}

/* When canvas beats intensely, we could pulse the panel, or let user hide it. For now, we fade it out if cursor is idle */
body.idle .dashboard-panel,
body.idle .top-bar {
    opacity: 0;
    pointer-events: none;
}

.control-group {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.control-group h3 {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted);
    font-weight: 600;
}

.source-toggles,
.filter-toggles {
    display: flex;
    gap: 0.5rem;
}

.btn {
    font-family: var(--font-sans);
    font-size: 0.875rem;
    font-weight: 500;
    border-radius: var(--radius-sm);
    padding: 0.6rem 1rem;
    cursor: pointer;
    border: 1px solid transparent;
    transition: all 0.2s;
    display: inline-flex;
    justify-content: center;
    align-items: center;
}

.btn.primary {
    background: var(--primary);
    color: #fff;
}

.btn.primary:hover {
    filter: brightness(1.1);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

.btn.secondary {
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-main);
    border-color: var(--glass-border);
}

.btn.secondary:hover {
    background: rgba(255, 255, 255, 0.1);
}

.btn.ghost {
    background: transparent;
    color: var(--text-muted);
    padding: 0.5rem;
}

.btn.ghost:hover {
    color: var(--text-main);
    background: rgba(255, 255, 255, 0.1);
}

.btn.icon-btn svg {
    width: 18px;
    height: 18px;
}

.btn.icon-btn.huge svg {
    width: 32px;
    height: 32px;
}

.btn.full {
    flex: 1;
}

.track-info {
    font-size: 0.75rem;
    color: var(--primary);
    font-weight: 500;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    text-align: center;
}

/* Modes Grid */
.modes-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.5rem;
}

.mode-btn,
.filter-btn {
    background: rgba(0, 0, 0, 0.3);
    border: 1px solid var(--glass-border);
    color: var(--text-muted);
    font-size: 0.8125rem;
    padding: 0.5rem;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all 0.2s;
}

.mode-btn:hover,
.filter-btn:hover {
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-main);
}

.mode-btn.active,
.filter-btn.active {
    background: rgba(99, 102, 241, 0.15);
    border-color: var(--primary);
    color: var(--text-main);
    box-shadow: inset 0 0 12px rgba(99, 102, 241, 0.1);
}

/* Colors flex */
.colors-flex {
    display: flex;
    gap: 0.75rem;
}

.color-swatch {
    width: 24px;
    height: 24px;
    border-radius: 50%;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
    border: 2px solid transparent;
}

.color-swatch:hover {
    transform: scale(1.1);
}

.color-swatch.active {
    border-color: #fff;
    transform: scale(1.1);
    box-shadow: 0 0 10px rgba(255, 255, 255, 0.3);
}

/* Range Sliders */
.flex-between {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.value-display {
    font-size: 0.7rem;
    color: var(--text-muted);
    font-variant-numeric: tabular-nums;
}

.mt-3 {
    margin-top: 0.75rem;
}

input[type=range] {
    -webkit-appearance: none;
    width: 100%;
    background: transparent;
}

input[type=range]::-webkit-slider-thumb {
    -webkit-appearance: none;
    height: 14px;
    width: 14px;
    border-radius: 50%;
    background: var(--primary);
    cursor: pointer;
    margin-top: -5px;
    box-shadow: 0 0 10px rgba(99, 102, 241, 0.5);
}

input[type=range]::-webkit-slider-runnable-track {
    width: 100%;
    height: 4px;
    cursor: pointer;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 2px;
}

input[type=range]:focus {
    outline: none;
}

/* Playback */
.playback-controls {
    display: flex;
    justify-content: center;
    margin-top: 0.5rem;
}