/* ============================================================
   WebMix Studio — Design System & Styles
   Professional DAW UI with dark theme, glassmorphism, neon glow
   ============================================================ */

/* ---------- Google Fonts ---------- */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&family=JetBrains+Mono:wght@400;500;600&display=swap');

/* ---------- CSS Custom Properties (Design Tokens) ---------- */
:root {
    /* Surface Colors */
    --bg-primary: #0a0a0f;
    --bg-secondary: #111118;
    --bg-tertiary: #1a1a24;
    --bg-surface: #16161f;
    --bg-elevated: #1e1e2a;
    --bg-track: #13131c;
    --bg-track-hover: #1a1a26;
    --bg-clip: rgba(99, 102, 241, 0.25);
    --bg-clip-selected: rgba(139, 92, 246, 0.35);
    --bg-glass: rgba(20, 20, 30, 0.7);
    --bg-glass-hover: rgba(30, 30, 45, 0.8);
    --bg-input: rgba(255, 255, 255, 0.04);

    /* Accent Colors */
    --accent-primary: #6366f1;
    --accent-primary-hover: #818cf8;
    --accent-secondary: #8b5cf6;
    --accent-tertiary: #a78bfa;
    --accent-cyan: #22d3ee;
    --accent-pink: #ec4899;
    --accent-green: #10b981;
    --accent-orange: #f59e0b;
    --accent-red: #ef4444;
    --accent-blue: #3b82f6;

    /* Text Colors */
    --text-primary: #f0f0f5;
    --text-secondary: #9ca3af;
    --text-tertiary: #6b7280;
    --text-muted: #4b5563;

    /* Border Colors */
    --border-subtle: rgba(255, 255, 255, 0.06);
    --border-default: rgba(255, 255, 255, 0.1);
    --border-active: rgba(99, 102, 241, 0.4);
    --border-glow: rgba(99, 102, 241, 0.6);

    /* Neon Glow */
    --glow-primary: 0 0 20px rgba(99, 102, 241, 0.3), 0 0 40px rgba(99, 102, 241, 0.1);
    --glow-accent: 0 0 15px rgba(139, 92, 246, 0.3);
    --glow-cyan: 0 0 15px rgba(34, 211, 238, 0.3);
    --glow-green: 0 0 12px rgba(16, 185, 129, 0.3);
    --glow-red: 0 0 12px rgba(239, 68, 68, 0.3);
    --glow-playhead: 0 0 8px rgba(239, 68, 68, 0.6), 0 0 20px rgba(239, 68, 68, 0.2);

    /* Spacing */
    --sp-xs: 4px;
    --sp-sm: 8px;
    --sp-md: 12px;
    --sp-lg: 16px;
    --sp-xl: 24px;
    --sp-2xl: 32px;
    --sp-3xl: 48px;

    /* Track Layout */
    --track-header-width: 240px;
    --track-height: 80px;
    --timeline-ruler-height: 36px;
    --toolbar-height: 56px;
    --transport-height: 64px;

    /* Radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    --radius-full: 9999px;

    /* Transitions */
    --transition-fast: 120ms ease;
    --transition-normal: 200ms ease;
    --transition-smooth: 300ms cubic-bezier(0.4, 0, 0.2, 1);

    /* Typography */
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'JetBrains Mono', 'SF Mono', monospace;

    /* Z-index layers */
    --z-base: 1;
    --z-tracks: 10;
    --z-clips: 20;
    --z-playhead: 50;
    --z-toolbar: 100;
    --z-modal: 200;
    --z-tooltip: 300;
    --z-context-menu: 400;
}

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

html,
body {
    width: 100%;
    height: 100%;
    overflow: hidden;
    font-family: var(--font-sans);
    font-size: 13px;
    color: var(--text-primary);
    background: var(--bg-primary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    user-select: none;
}

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

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

::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.12);
    border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
    background: rgba(255, 255, 255, 0.2);
}

/* Selection */
::selection {
    background: rgba(99, 102, 241, 0.3);
    color: #fff;
}

/* ---------- App Layout ---------- */
#app {
    display: flex;
    flex-direction: column;
    width: 100%;
    height: 100vh;
    background: var(--bg-primary);
    border: 1px solid rgba(99, 102, 241, 0.15);
    box-shadow: inset 0 0 80px rgba(99, 102, 241, 0.03), 0 0 60px rgba(99, 102, 241, 0.06);
}

/* ---------- Top Toolbar ---------- */
#toolbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: var(--toolbar-height);
    padding: 0 var(--sp-md);
    background: var(--bg-glass);
    backdrop-filter: blur(20px) saturate(1.2);
    -webkit-backdrop-filter: blur(20px) saturate(1.2);
    border-bottom: 1px solid var(--border-subtle);
    z-index: var(--z-toolbar);
    flex-shrink: 0;
    gap: var(--sp-sm);
    overflow-x: auto;
    overflow-y: hidden;
}

.toolbar-left {
    display: flex;
    align-items: center;
    gap: var(--sp-sm);
    flex-shrink: 0;
}

.toolbar-center {
    display: flex;
    align-items: center;
    gap: var(--sp-xs);
    flex-shrink: 0;
}

.toolbar-right {
    display: flex;
    align-items: center;
    gap: var(--sp-md);
    flex-shrink: 0;
}

/* Logo */
.logo {
    display: flex;
    align-items: center;
    gap: var(--sp-sm);
    font-size: 16px;
    font-weight: 700;
    letter-spacing: -0.5px;
    color: var(--text-primary);
}

.logo-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    border-radius: var(--radius-md);
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    box-shadow: var(--glow-primary);
    font-size: 16px;
}

.logo-text span {
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-cyan));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Toolbar Buttons */
.toolbar-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--sp-xs);
    height: 34px;
    padding: 0 var(--sp-md);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    background: var(--bg-input);
    color: var(--text-secondary);
    font-family: var(--font-sans);
    font-size: 12px;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-normal);
    white-space: nowrap;
}

.toolbar-btn:hover {
    background: var(--bg-glass-hover);
    color: var(--text-primary);
    border-color: var(--border-default);
}

.toolbar-btn.active {
    background: rgba(99, 102, 241, 0.15);
    color: var(--accent-primary-hover);
    border-color: var(--border-active);
}

.toolbar-btn.danger:hover {
    background: rgba(239, 68, 68, 0.12);
    color: var(--accent-red);
    border-color: rgba(239, 68, 68, 0.3);
}

.toolbar-btn svg {
    width: 16px;
    height: 16px;
    flex-shrink: 0;
}

.toolbar-divider {
    width: 1px;
    height: 24px;
    background: var(--border-subtle);
    margin: 0 var(--sp-xs);
}

/* ---------- Transport Bar ---------- */
#transport {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--sp-xl);
    height: var(--transport-height);
    padding: 0 var(--sp-xl);
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-subtle);
    flex-shrink: 0;
}

.transport-controls {
    display: flex;
    align-items: center;
    gap: var(--sp-sm);
}

.transport-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border: none;
    border-radius: var(--radius-full);
    background: var(--bg-glass);
    color: var(--text-secondary);
    cursor: pointer;
    transition: all var(--transition-normal);
    font-size: 18px;
}

.transport-btn:hover {
    background: var(--bg-glass-hover);
    color: var(--text-primary);
    transform: scale(1.05);
}

.transport-btn.play-btn {
    width: 48px;
    height: 48px;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    color: #fff;
    box-shadow: var(--glow-primary);
    font-size: 20px;
}

.transport-btn.play-btn:hover {
    transform: scale(1.1);
    box-shadow: 0 0 30px rgba(99, 102, 241, 0.5), 0 0 60px rgba(99, 102, 241, 0.2);
}

.transport-btn.play-btn.playing {
    background: linear-gradient(135deg, var(--accent-green), #059669);
    box-shadow: var(--glow-green);
    animation: pulse-glow 2s ease-in-out infinite;
}

.transport-btn.stop-btn:hover {
    background: rgba(239, 68, 68, 0.15);
    color: var(--accent-red);
}

.transport-btn.record-btn.active {
    background: var(--accent-red);
    color: #fff;
    box-shadow: var(--glow-red);
    animation: pulse-glow-red 1s ease-in-out infinite;
}

@keyframes pulse-glow {

    0%,
    100% {
        box-shadow: var(--glow-green);
    }

    50% {
        box-shadow: 0 0 25px rgba(16, 185, 129, 0.5), 0 0 50px rgba(16, 185, 129, 0.2);
    }
}

@keyframes pulse-glow-red {

    0%,
    100% {
        box-shadow: var(--glow-red);
    }

    50% {
        box-shadow: 0 0 20px rgba(239, 68, 68, 0.6), 0 0 40px rgba(239, 68, 68, 0.3);
    }
}

/* Time Display */
.time-display {
    display: flex;
    align-items: center;
    gap: var(--sp-md);
    padding: var(--sp-sm) var(--sp-lg);
    background: var(--bg-glass);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
}

.time-value {
    font-family: var(--font-mono);
    font-size: 22px;
    font-weight: 600;
    color: var(--text-primary);
    letter-spacing: 1px;
    min-width: 140px;
    text-align: center;
}

.time-label {
    font-size: 10px;
    font-weight: 500;
    color: var(--text-tertiary);
    text-transform: uppercase;
    letter-spacing: 1px;
}

/* BPM / Tempo */
.tempo-control {
    display: flex;
    align-items: center;
    gap: var(--sp-sm);
    padding: var(--sp-sm) var(--sp-md);
    background: var(--bg-glass);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
}

.tempo-input {
    width: 50px;
    background: transparent;
    border: none;
    outline: none;
    color: var(--text-primary);
    font-family: var(--font-mono);
    font-size: 15px;
    font-weight: 600;
    text-align: center;
}

.tempo-label {
    font-size: 10px;
    font-weight: 500;
    color: var(--text-tertiary);
    text-transform: uppercase;
    letter-spacing: 1px;
}

/* Snap, Loop toggles */
.toggle-group {
    display: flex;
    align-items: center;
    gap: var(--sp-xs);
}

.toggle-btn {
    display: flex;
    align-items: center;
    gap: var(--sp-xs);
    height: 30px;
    padding: 0 var(--sp-md);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    background: transparent;
    color: var(--text-tertiary);
    font-family: var(--font-sans);
    font-size: 11px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.toggle-btn:hover {
    color: var(--text-secondary);
    border-color: var(--border-default);
}

.toggle-btn.active {
    color: var(--accent-cyan);
    border-color: rgba(34, 211, 238, 0.3);
    background: rgba(34, 211, 238, 0.08);
    box-shadow: var(--glow-cyan);
}

/* ---------- Main Workspace ---------- */
#workspace {
    display: flex;
    flex-direction: column;
    flex: 1;
    overflow: hidden;
    position: relative;
}

/* ---------- Timeline Ruler ---------- */
#timeline-ruler {
    display: flex;
    height: var(--timeline-ruler-height);
    background: var(--bg-tertiary);
    border-bottom: 1px solid var(--border-default);
    flex-shrink: 0;
    position: relative;
    z-index: var(--z-playhead);
}

.ruler-header-spacer {
    width: var(--track-header-width);
    flex-shrink: 0;
    background: var(--bg-secondary);
    border-right: 1px solid var(--border-subtle);
    border-bottom: 1px solid var(--border-default);
    display: flex;
    align-items: center;
    justify-content: center;
}

.ruler-header-spacer span {
    font-size: 10px;
    font-weight: 600;
    color: var(--text-tertiary);
    text-transform: uppercase;
    letter-spacing: 1px;
}

#ruler-canvas-wrapper {
    flex: 1;
    overflow: hidden;
    position: relative;
}

#ruler-canvas {
    display: block;
    cursor: pointer;
}

/* ---------- Tracks Container ---------- */
#tracks-container {
    display: flex;
    flex: 1;
    overflow: hidden;
    position: relative;
}

/* Track Headers (left panel) */
#track-headers {
    width: var(--track-header-width);
    flex-shrink: 0;
    overflow-y: auto;
    overflow-x: hidden;
    background: var(--bg-secondary);
    border-right: 1px solid var(--border-subtle);
    z-index: var(--z-tracks);
}

.track-header {
    display: flex;
    flex-direction: column;
    justify-content: center;
    height: var(--track-height);
    padding: var(--sp-sm) var(--sp-md);
    border-bottom: 1px solid var(--border-subtle);
    transition: background var(--transition-fast);
    position: relative;
    cursor: default;
}

.track-header:hover {
    background: var(--bg-track-hover);
}

.track-header.selected {
    background: rgba(99, 102, 241, 0.06);
    border-left: 3px solid var(--accent-primary);
    padding-left: calc(var(--sp-md) - 3px);
}

.track-header-top {
    display: flex;
    align-items: center;
    gap: var(--sp-sm);
    margin-bottom: var(--sp-xs);
}

.track-color-dot {
    width: 10px;
    height: 10px;
    border-radius: var(--radius-full);
    flex-shrink: 0;
    cursor: pointer;
    transition: transform var(--transition-fast);
}

.track-color-dot:hover {
    transform: scale(1.3);
}

.track-name {
    flex: 1;
    background: transparent;
    border: none;
    outline: none;
    color: var(--text-primary);
    font-family: var(--font-sans);
    font-size: 12px;
    font-weight: 600;
    padding: 2px 4px;
    border-radius: var(--radius-sm);
    transition: background var(--transition-fast);
    min-width: 0;
}

.track-name:hover {
    background: var(--bg-input);
}

.track-name:focus {
    background: var(--bg-input);
    box-shadow: 0 0 0 1px var(--accent-primary);
}

.track-remove-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 18px;
    height: 18px;
    border: none;
    border-radius: var(--radius-sm);
    background: transparent;
    color: var(--text-muted);
    cursor: pointer;
    font-size: 12px;
    opacity: 0;
    transition: all var(--transition-fast);
}

.track-header:hover .track-remove-btn {
    opacity: 1;
}

.track-remove-btn:hover {
    background: rgba(239, 68, 68, 0.15);
    color: var(--accent-red);
}

.track-header-controls {
    display: flex;
    align-items: center;
    gap: var(--sp-xs);
}

.track-ctrl-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 26px;
    height: 22px;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-sm);
    background: transparent;
    color: var(--text-tertiary);
    font-family: var(--font-sans);
    font-size: 10px;
    font-weight: 700;
    cursor: pointer;
    transition: all var(--transition-fast);
    text-transform: uppercase;
}

.track-ctrl-btn:hover {
    border-color: var(--border-default);
    color: var(--text-secondary);
}

.track-ctrl-btn.mute-btn.active {
    background: rgba(245, 158, 11, 0.15);
    color: var(--accent-orange);
    border-color: rgba(245, 158, 11, 0.3);
}

.track-ctrl-btn.solo-btn.active {
    background: rgba(34, 211, 238, 0.15);
    color: var(--accent-cyan);
    border-color: rgba(34, 211, 238, 0.3);
}

/* Volume Slider */
.track-volume-wrapper {
    display: flex;
    align-items: center;
    gap: var(--sp-xs);
    flex: 1;
}

.track-volume-label {
    font-family: var(--font-mono);
    font-size: 9px;
    color: var(--text-muted);
    min-width: 22px;
    text-align: right;
}

.track-volume {
    -webkit-appearance: none;
    appearance: none;
    flex: 1;
    height: 3px;
    background: var(--bg-tertiary);
    border-radius: 2px;
    outline: none;
    cursor: pointer;
}

.track-volume::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--accent-primary);
    cursor: pointer;
    transition: transform var(--transition-fast);
    box-shadow: 0 0 6px rgba(99, 102, 241, 0.4);
}

.track-volume::-webkit-slider-thumb:hover {
    transform: scale(1.3);
    box-shadow: 0 0 10px rgba(99, 102, 241, 0.6);
}

/* Pan knob */
.track-pan-wrapper {
    display: flex;
    align-items: center;
    gap: 2px;
}

.track-pan-label {
    font-family: var(--font-mono);
    font-size: 8px;
    color: var(--text-muted);
    width: 14px;
    text-align: center;
}

.track-pan {
    -webkit-appearance: none;
    appearance: none;
    width: 40px;
    height: 3px;
    background: linear-gradient(to right, var(--accent-cyan), var(--bg-tertiary) 50%, var(--accent-pink));
    border-radius: 2px;
    outline: none;
    cursor: pointer;
}

.track-pan::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: #fff;
    cursor: pointer;
    box-shadow: 0 0 4px rgba(255, 255, 255, 0.3);
}

/* ---------- Track Lanes (Canvas Area) ---------- */
#track-lanes {
    flex: 1;
    overflow: auto;
    position: relative;
    background: var(--bg-primary);
}

#track-lanes-canvas {
    display: block;
    cursor: crosshair;
}

/* Playhead line (drawn on canvas but CSS for overlay) */
.playhead-line {
    position: absolute;
    top: 0;
    width: 2px;
    height: 100%;
    background: var(--accent-red);
    box-shadow: var(--glow-playhead);
    z-index: var(--z-playhead);
    pointer-events: none;
    transition: none;
}

.playhead-head {
    position: absolute;
    top: -2px;
    left: -5px;
    width: 12px;
    height: 12px;
    background: var(--accent-red);
    clip-path: polygon(0 0, 100% 0, 50% 100%);
    filter: drop-shadow(0 0 4px rgba(239, 68, 68, 0.5));
}

/* ---------- Clip Styles (rendered on canvas, but context menu) ---------- */

/* ---------- Context Menu ---------- */
.context-menu {
    position: fixed;
    min-width: 180px;
    padding: var(--sp-xs) 0;
    background: var(--bg-glass);
    backdrop-filter: blur(20px) saturate(1.5);
    -webkit-backdrop-filter: blur(20px) saturate(1.5);
    border: 1px solid var(--border-default);
    border-radius: var(--radius-lg);
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5), 0 0 1px rgba(255, 255, 255, 0.1);
    z-index: var(--z-context-menu);
    animation: ctx-appear 150ms cubic-bezier(0.16, 1, 0.3, 1);
    overflow: hidden;
}

@keyframes ctx-appear {
    from {
        opacity: 0;
        transform: scale(0.95) translateY(-4px);
    }

    to {
        opacity: 1;
        transform: scale(1) translateY(0);
    }
}

.context-menu-item {
    display: flex;
    align-items: center;
    gap: var(--sp-sm);
    padding: var(--sp-sm) var(--sp-lg);
    color: var(--text-secondary);
    font-size: 12px;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.context-menu-item:hover {
    background: rgba(99, 102, 241, 0.1);
    color: var(--text-primary);
}

.context-menu-item.danger:hover {
    background: rgba(239, 68, 68, 0.1);
    color: var(--accent-red);
}

.context-menu-item .shortcut {
    margin-left: auto;
    font-family: var(--font-mono);
    font-size: 10px;
    color: var(--text-muted);
}

.context-menu-divider {
    height: 1px;
    margin: var(--sp-xs) 0;
    background: var(--border-subtle);
}

/* ---------- Drop Zone / Empty State ---------- */
.empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: var(--sp-lg);
    padding: var(--sp-3xl);
    color: var(--text-tertiary);
    text-align: center;
}

.empty-state-icon {
    font-size: 48px;
    opacity: 0.5;
}

.empty-state-title {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-secondary);
}

.empty-state-text {
    font-size: 13px;
    max-width: 400px;
    line-height: 1.6;
}

/* Drop zone overlay */
.drop-overlay {
    position: fixed;
    inset: 0;
    background: rgba(10, 10, 15, 0.85);
    backdrop-filter: blur(8px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: var(--z-modal);
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition-smooth);
}

.drop-overlay.active {
    opacity: 1;
    pointer-events: all;
}

.drop-zone {
    width: 420px;
    height: 280px;
    border: 2px dashed var(--accent-primary);
    border-radius: var(--radius-xl);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: var(--sp-md);
    color: var(--accent-primary-hover);
    animation: drop-pulse 2s ease-in-out infinite;
}

@keyframes drop-pulse {

    0%,
    100% {
        border-color: var(--accent-primary);
        box-shadow: var(--glow-primary);
    }

    50% {
        border-color: var(--accent-secondary);
        box-shadow: var(--glow-accent);
    }
}

.drop-zone-icon {
    font-size: 48px;
}

.drop-zone-text {
    font-size: 16px;
    font-weight: 600;
}

.drop-zone-hint {
    font-size: 12px;
    color: var(--text-tertiary);
}

/* ---------- Loop Region ---------- */
.loop-region {
    position: absolute;
    top: 0;
    height: 100%;
    background: rgba(34, 211, 238, 0.06);
    border-left: 2px solid rgba(34, 211, 238, 0.4);
    border-right: 2px solid rgba(34, 211, 238, 0.4);
    pointer-events: none;
    z-index: calc(var(--z-clips) - 1);
}

/* ---------- Status Bar ---------- */
#status-bar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 28px;
    padding: 0 var(--sp-md);
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-subtle);
    flex-shrink: 0;
    font-size: 11px;
    color: var(--text-tertiary);
}

.status-left,
.status-right {
    display: flex;
    align-items: center;
    gap: var(--sp-md);
}

.status-indicator {
    display: flex;
    align-items: center;
    gap: 4px;
}

.status-dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--accent-green);
    box-shadow: 0 0 4px rgba(16, 185, 129, 0.4);
}

/* ---------- Modal ---------- */
.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(4px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: var(--z-modal);
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition-smooth);
}

.modal-overlay.active {
    opacity: 1;
    pointer-events: all;
}

.modal {
    width: 90%;
    max-width: 480px;
    padding: var(--sp-xl);
    background: var(--bg-glass);
    backdrop-filter: blur(20px) saturate(1.4);
    border: 1px solid var(--border-default);
    border-radius: var(--radius-xl);
    box-shadow: 0 30px 80px rgba(0, 0, 0, 0.5);
    transform: translateY(20px) scale(0.95);
    transition: transform var(--transition-smooth);
}

.modal-overlay.active .modal {
    transform: translateY(0) scale(1);
}

.modal-title {
    font-size: 16px;
    font-weight: 700;
    margin-bottom: var(--sp-lg);
    color: var(--text-primary);
}

.modal-body {
    color: var(--text-secondary);
    font-size: 13px;
    line-height: 1.6;
}

.modal-actions {
    display: flex;
    justify-content: flex-end;
    gap: var(--sp-sm);
    margin-top: var(--sp-xl);
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--sp-xs);
    padding: var(--sp-sm) var(--sp-lg);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    background: var(--bg-input);
    color: var(--text-secondary);
    font-family: var(--font-sans);
    font-size: 12px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
}

.btn:hover {
    background: var(--bg-glass-hover);
    color: var(--text-primary);
}

.btn-primary {
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    color: #fff;
    border: none;
    box-shadow: var(--glow-primary);
}

.btn-primary:hover {
    box-shadow: 0 0 25px rgba(99, 102, 241, 0.4);
    transform: translateY(-1px);
}

/* ---------- Tooltip ---------- */
.tooltip {
    position: fixed;
    padding: 4px 8px;
    background: var(--bg-elevated);
    border: 1px solid var(--border-default);
    border-radius: var(--radius-sm);
    font-size: 11px;
    color: var(--text-primary);
    z-index: var(--z-tooltip);
    pointer-events: none;
    white-space: nowrap;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

/* ---------- Add Track Button ---------- */
.add-track-area {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--sp-lg);
    border-bottom: 1px solid var(--border-subtle);
}

.add-track-btn {
    display: flex;
    align-items: center;
    gap: var(--sp-sm);
    padding: var(--sp-sm) var(--sp-lg);
    border: 1px dashed var(--border-default);
    border-radius: var(--radius-md);
    background: transparent;
    color: var(--text-tertiary);
    font-family: var(--font-sans);
    font-size: 12px;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-normal);
    width: 100%;
    justify-content: center;
}

.add-track-btn:hover {
    border-color: var(--accent-primary);
    color: var(--accent-primary-hover);
    background: rgba(99, 102, 241, 0.05);
}

/* ---------- Loading Indicator ---------- */
.loading-spinner {
    display: inline-block;
    width: 16px;
    height: 16px;
    border: 2px solid var(--border-subtle);
    border-top-color: var(--accent-primary);
    border-radius: 50%;
    animation: spin 0.7s linear infinite;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

/* ---------- Waveform clip color variants ---------- */
.clip-color-0 {
    --clip-hue: 240;
}

.clip-color-1 {
    --clip-hue: 270;
}

.clip-color-2 {
    --clip-hue: 170;
}

.clip-color-3 {
    --clip-hue: 330;
}

.clip-color-4 {
    --clip-hue: 30;
}

.clip-color-5 {
    --clip-hue: 200;
}

.clip-color-6 {
    --clip-hue: 120;
}

.clip-color-7 {
    --clip-hue: 0;
}

.clip-color-8 {
    --clip-hue: 60;
}

.clip-color-9 {
    --clip-hue: 290;
}

/* ---------- Color Picker Popup ---------- */
.color-picker-popup {
    position: absolute;
    top: calc(100% + 4px);
    left: var(--sp-md);
    display: flex;
    gap: 4px;
    padding: var(--sp-sm);
    background: var(--bg-glass);
    backdrop-filter: blur(20px);
    border: 1px solid var(--border-default);
    border-radius: var(--radius-md);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.4);
    z-index: var(--z-context-menu);
    animation: ctx-appear 120ms ease;
}

.color-picker-swatch {
    width: 18px;
    height: 18px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    border: 2px solid transparent;
    transition: all var(--transition-fast);
}

.color-picker-swatch:hover {
    transform: scale(1.2);
    border-color: rgba(255, 255, 255, 0.3);
}

.color-picker-swatch.active {
    border-color: #fff;
    box-shadow: 0 0 8px rgba(255, 255, 255, 0.3);
}

/* ---------- Zoom Controls ---------- */
.zoom-controls {
    display: flex;
    align-items: center;
    gap: var(--sp-xs);
}

.zoom-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 26px;
    height: 26px;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-sm);
    background: transparent;
    color: var(--text-tertiary);
    cursor: pointer;
    font-size: 14px;
    font-weight: 700;
    transition: all var(--transition-fast);
}

.zoom-btn:hover {
    background: var(--bg-glass-hover);
    color: var(--text-primary);
    border-color: var(--border-default);
}

.zoom-level {
    font-family: var(--font-mono);
    font-size: 10px;
    color: var(--text-tertiary);
    min-width: 36px;
    text-align: center;
}

/* ---------- Responsive ---------- */
@media (max-width: 768px) {
    :root {
        --track-header-width: 160px;
        --track-height: 64px;
        --toolbar-height: 48px;
        --transport-height: 52px;
    }

    .toolbar-btn span {
        display: none;
    }

    .time-value {
        font-size: 16px;
        min-width: 100px;
    }

    .tempo-control {
        display: none;
    }
}

/* ---------- Utility ---------- */
.hidden {
    display: none !important;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    border: 0;
}