/* ============================================
   Vocal Check Note - Design System & Styles
   ============================================ */

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

/* --- Custom Scrollbar --- */
::-webkit-scrollbar {
    width: 10px;
    height: 10px;
}

::-webkit-scrollbar-track {
    background: var(--surface-active);
}

::-webkit-scrollbar-thumb {
    background: var(--primary);
    /* High visibility */
    border-radius: 5px;
    border: 2px solid var(--surface-active);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--primary-hover);
}

/* For Firefox */
* {
    scrollbar-width: thin;
    scrollbar-color: var(--primary) var(--surface-active);
}

/* ============================================
   CSS Custom Properties (Theme Tokens)
   ============================================ */

:root {
    /* Typography */
    --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-mono: 'JetBrains Mono', 'Consolas', monospace;

    /* Spacing */
    --sp-2: 2px;
    --sp-4: 4px;
    --sp-6: 6px;
    --sp-8: 8px;
    --sp-10: 10px;
    --sp-12: 12px;
    --sp-16: 16px;
    --sp-20: 20px;
    --sp-24: 24px;

    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 6px;
    --radius-lg: 8px;
    --radius-xl: 12px;

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-normal: 250ms ease;
    --transition-slow: 400ms cubic-bezier(0.4, 0, 0.2, 1);

    /* Shadows (defined per theme) */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.1);

    /* Z-index layers */
    --z-base: 1;
    --z-dropdown: 10;
    --z-modal: 100;
    --z-tooltip: 200;
}

/* ============================================
   Day Mode (Studio Light) - Default
   ============================================ */
[data-theme="day"] {
    --bg: #F8FAFC;
    --surface: #FFFFFF;
    --surface-hover: #F1F5F9;
    --surface-active: #E2E8F0;
    --text-primary: #1E293B;
    --text-secondary: #64748B;
    --text-tertiary: #94A3B8;
    --primary: #3B82F6;
    --primary-hover: #2563EB;
    --primary-light: rgba(59, 130, 246, 0.1);
    --primary-border: rgba(59, 130, 246, 0.3);
    --border: #E2E8F0;
    --border-light: #F1F5F9;
    --waveform-base: #93C5FD;
    --waveform-progress: #2563EB;
    --danger: #EF4444;
    --danger-light: rgba(239, 68, 68, 0.1);
    --success: #22C55E;
    --success-light: rgba(34, 197, 94, 0.1);
    --warning: #F59E0B;
    --warning-light: rgba(245, 158, 11, 0.1);
    --scrollbar-track: #F1F5F9;
    --scrollbar-thumb: #CBD5E1;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.1);
    --input-bg: #FFFFFF;
    --input-border: #D1D5DB;
    --badge-bg: #EFF6FF;
    --badge-text: #3B82F6;
    --overlay: rgba(0, 0, 0, 0.3);
    --timestamp-bg: #DBEAFE;
    --timestamp-text: #1D4ED8;
    --lyrics-active-bg: rgba(59, 130, 246, 0.08);
    --lyrics-hover-bg: rgba(59, 130, 246, 0.04);
    --drop-zone-bg: rgba(59, 130, 246, 0.05);
    --drop-zone-border: rgba(59, 130, 246, 0.3);
    --memo-highlight: #EFF6FF;
    /* cool light blue */
}

/* ============================================
   Night Mode (Midnight Stage)
   ============================================ */
[data-theme="night"] {
    --bg: #0F172A;
    --surface: #1E293B;
    --surface-hover: #273548;
    --surface-active: #334155;
    --text-primary: #E2E8F0;
    --text-secondary: #94A3B8;
    --text-tertiary: #64748B;
    --primary: #818CF8;
    --primary-hover: #A855F7;
    --primary-light: rgba(129, 140, 248, 0.1);
    --primary-border: rgba(129, 140, 248, 0.3);
    --border: #334155;
    --border-light: #1E293B;
    --waveform-base: #4F46E5;
    --waveform-progress: #A855F7;
    --danger: #F87171;
    --danger-light: rgba(248, 113, 113, 0.1);
    --success: #4ADE80;
    --success-light: rgba(74, 222, 128, 0.1);
    --warning: #FBBF24;
    --warning-light: rgba(251, 191, 36, 0.1);
    --scrollbar-track: #1E293B;
    --scrollbar-thumb: #475569;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 8px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.5);
    --input-bg: #0F172A;
    --input-border: #475569;
    --badge-bg: rgba(129, 140, 248, 0.15);
    --badge-text: #A5B4FC;
    --overlay: rgba(0, 0, 0, 0.6);
    --timestamp-bg: rgba(79, 70, 229, 0.2);
    --timestamp-text: #A5B4FC;
    --lyrics-active-bg: rgba(129, 140, 248, 0.1);
    --lyrics-hover-bg: rgba(129, 140, 248, 0.05);
    --drop-zone-bg: rgba(129, 140, 248, 0.05);
    --drop-zone-border: rgba(129, 140, 248, 0.3);
    --memo-highlight: rgba(251, 191, 36, 0.1);
}

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

html {
    font-size: 14px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-primary);
    background: var(--bg);
    color: var(--text-primary);
    line-height: 1.5;
    overflow: hidden;
    height: 100vh;
    width: 100vw;
    transition: background var(--transition-normal), color var(--transition-normal);
}

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

::-webkit-scrollbar-track {
    background: var(--scrollbar-track);
    border-radius: 3px;
}

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

::-webkit-scrollbar-thumb:hover {
    background: var(--text-tertiary);
}

/* ============================================
   App Shell
   ============================================ */
#app {
    display: flex;
    flex-direction: column;
    height: 100vh;
    padding: var(--sp-8);
    gap: var(--sp-8);
}

/* ============================================
   Header Bar
   ============================================ */
.header-bar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--sp-6) var(--sp-12);
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    flex-shrink: 0;
    min-height: 40px;
    box-shadow: var(--shadow-sm);
}

.header-left {
    display: flex;
    align-items: center;
    gap: var(--sp-10);
}

.app-logo {
    display: flex;
    align-items: center;
    gap: var(--sp-8);
}

.app-logo-icon {
    width: 28px;
    height: 28px;
    background: linear-gradient(135deg, var(--primary), var(--primary-hover));
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    box-shadow: 0 2px 8px rgba(59, 130, 246, 0.3);
}

.app-logo h1 {
    font-size: 1rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    background: linear-gradient(135deg, var(--primary), var(--primary-hover));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.header-right {
    display: flex;
    align-items: center;
    gap: var(--sp-8);
}

.header-status {
    font-size: 0.75rem;
    color: var(--text-tertiary);
    font-family: var(--font-mono);
}

/* ============================================
   Theme Toggle
   ============================================ */
.theme-toggle {
    position: relative;
    width: 52px;
    height: 26px;
    border-radius: 13px;
    cursor: pointer;
    transition: background var(--transition-normal), border-color var(--transition-normal);
    flex-shrink: 0;
    overflow: hidden;
}

.theme-toggle::after {
    content: '';
    position: absolute;
    top: 2px;
    left: 2px;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    transition: transform var(--transition-normal), background var(--transition-normal), box-shadow var(--transition-normal);
    z-index: 2;
}

[data-theme="day"] .theme-toggle {
    background: #87CEEB;
    border: 1px solid #7BC0DF;
}

[data-theme="day"] .theme-toggle::after {
    background: #FFD700;
    box-shadow: 0 0 6px rgba(255, 215, 0, 0.8);
}

[data-theme="night"] .theme-toggle {
    background: #1E293B;
    border: 1px solid #334155;
}

[data-theme="night"] .theme-toggle::after {
    transform: translateX(26px);
    background: #E2E8F0;
    box-shadow: 0 0 4px rgba(226, 232, 240, 0.8);
}

.theme-toggle-label {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    font-size: 12px;
    line-height: 1;
    pointer-events: none;
}

.theme-toggle-label.sun {
    right: 6px;
}

.theme-toggle-label.moon {
    left: 6px;
}

/* ============================================
   Main Content Area (3 Pane)
   ============================================ */
.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: var(--sp-8);
    min-height: 0;
    overflow: hidden;
}

/* --- Top: Media Area --- */
.media-area {
    display: flex;
    gap: var(--sp-8);
    flex-shrink: 0;
    height: 158px;
    /* Height matches single track perfectly */
    flex: 0 0 158px;
    min-height: 120px;
    overflow: hidden;
}

/* Waveform Panel */
.waveform-panel {
    flex: 1;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    display: flex;
    flex-direction: column;
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    min-width: 0;
    min-height: 0;
    /* CRITICAL: prevents panel from growing with content */
    max-height: 100%;
}

.waveform-panel .panel-header {
    padding: var(--sp-6) var(--sp-10);
    border-bottom: 1px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--text-secondary);
}

.waveform-header-left {
    display: flex;
    align-items: center;
    gap: var(--sp-6);
}

.waveform-header-right {
    display: flex;
    align-items: center;
    gap: var(--sp-8);
}

.offset-control,
.zoom-control {
    display: flex;
    align-items: center;
    gap: var(--sp-4);
    font-size: 0.75rem;
    color: var(--text-tertiary);
}

.zoom-control input[type="range"] {
    width: 80px;
    accent-color: var(--primary);
}

.offset-control label {
    font-family: var(--font-mono);
}

.offset-control input[type="number"] {
    width: 72px;
    padding: var(--sp-2) var(--sp-4);
    border: 1px solid var(--input-border);
    border-radius: var(--radius-sm);
    background: var(--input-bg);
    color: var(--text-primary);
    font-family: var(--font-mono);
    font-size: 0.75rem;
    text-align: center;
    outline: none;
}

.offset-control input[type="number"]:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 2px var(--primary-light);
}

.waveform-tracks {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    background: var(--bg);
}

.tracks-scroll-container {
    flex: 1;
    overflow-x: auto;
    overflow-y: auto;
    /* Essential for many tracks */
    min-height: 0;
    position: relative;
    background: var(--bg);
}

.tracks-inner {
    width: max-content;
    /* Ensure it grows exactly to children's width */
    min-width: 100%;
    display: flex;
    flex-direction: column;
    min-height: 100%;
}

.waveform-track {
    flex: 0 0 130px;
    /* Adjusted to fit waveform + timeline better */
    height: 130px;
    position: relative;
    border-bottom: 1px solid var(--border);
    display: flex;
    width: 100%;
}

.track-sidebar {
    position: sticky;
    left: 0;
    width: 140px;
    background: var(--surface-active);
    border-right: 1px solid var(--border);
    padding: var(--sp-2) var(--sp-4);
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: var(--sp-4);
    flex-shrink: 0;
    z-index: 10;
}

.waveform-timeline {
    position: sticky;
    top: 0;
    z-index: 20;
    height: 24px;
    /* Slightly taller for better readability */
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    font-size: 10px;
    font-family: var(--font-mono);
    color: var(--text-tertiary);
    width: 100%;
}

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

.track-volume-wrap {
    display: flex;
    align-items: center;
    gap: var(--sp-2);
}

.track-volume-wrap span {
    font-size: 0.7rem;
    color: var(--text-tertiary);
}

.track-volume-wrap input[type="range"] {
    flex: 1;
    min-width: 0;
    accent-color: var(--primary);
}

.waveform-drop-zone {
    display: flex;
    align-items: center;
    justify-content: center;
    flex: 1;
    min-height: 0;
    box-sizing: border-box;
    border: 2px dashed var(--drop-zone-border);
    border-radius: var(--radius-md);
    margin: var(--sp-4);
    background: var(--drop-zone-bg);
    cursor: pointer;
    transition: all var(--transition-fast);
    gap: var(--sp-8);
    color: var(--text-tertiary);
    font-size: 0.78rem;
}

.waveform-drop-zone:hover {
    border-color: var(--primary);
    background: var(--primary-light);
    color: var(--text-secondary);
}

.waveform-drop-zone.drag-over {
    border-color: var(--primary);
    background: var(--primary-light);
    transform: scale(1.01);
}

.waveform-drop-zone-icon {
    font-size: 1.2rem;
}

.waveform-container {
    height: 100%;
    width: 100%;
    padding: var(--sp-2) 0;
}

/* --- Middle: Work Area --- */
.work-area {
    flex: 1;
    display: flex;
    gap: var(--sp-8);
    min-height: 0;
    overflow: hidden;
}

/* Lyrics Panel */
.lyrics-panel {
    flex: 1;
    min-width: 0;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    display: flex;
    flex-direction: column;
    overflow: hidden;
    box-shadow: var(--shadow-sm);
}

.lyrics-panel .panel-header {
    padding: var(--sp-6) var(--sp-10);
    border-bottom: 1px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--text-secondary);
    flex-shrink: 0;
}

.lyrics-header-left {
    display: flex;
    align-items: center;
    gap: var(--sp-6);
}

.lyrics-header-right {
    display: flex;
    align-items: center;
    gap: var(--sp-6);
}

.lyrics-count {
    font-size: 0.7rem;
    font-family: var(--font-mono);
    color: var(--text-tertiary);
    padding: var(--sp-2) var(--sp-6);
    background: var(--badge-bg);
    color: var(--badge-text);
    border-radius: var(--radius-sm);
}

/* Lyrics Import Area */
.lyrics-import-area {
    display: flex;
    flex-direction: column;
    flex: 1;
    overflow: hidden;
    background-color: var(--surface);
    background-image: none !important;
}

.lyrics-import-textarea {
    flex: 1;
    width: 100%;
    padding: var(--sp-10);
    border: none;
    background-color: var(--input-bg);
    background-image: none !important;
    color: var(--text-primary);
    font-family: var(--font-primary);
    font-size: 0.85rem;
    resize: none;
    outline: none;
    line-height: 1.8;
}

.lyrics-import-textarea::placeholder {
    color: var(--text-tertiary);
}

.lyrics-import-actions {
    padding: var(--sp-6) var(--sp-10);
    border-top: 1px solid var(--border);
    display: flex;
    gap: var(--sp-6);
    justify-content: flex-end;
}

/* Lyrics List */
.lyrics-list-container {
    flex: 1;
    display: none;
    min-height: 0;
    background-color: var(--bg);
    background-image: none !important;
    overflow: hidden;
}

.lyrics-list-container.active {
    display: flex;
    flex-direction: column;
}

.list-headers {
    flex-shrink: 0;
}

#lyrics-list {
    padding-bottom: 80px;
    /* Buffer for last items */
    flex: 1;
    overflow-y: scroll;
    /* Force vertical scrollbar show */
    overflow-x: hidden;
    min-height: 0;
}

/* Timeline */
.waveform-timeline {
    height: 18px;
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    font-size: 10px;
    font-family: var(--font-mono);
    color: var(--text-tertiary);
}

.lyrics-list {
    list-style: none;
}

.lyrics-item {
    display: flex;
    border-bottom: 1px solid var(--border-light);
    cursor: pointer;
    transition: background var(--transition-fast);
    min-height: 48px;
    padding: 0;
    align-items: stretch;
}

.lyrics-item .col-lyric {
    display: flex;
    align-items: center;
    gap: var(--sp-4);
    border-right: 1px solid var(--border-light);
    padding: var(--sp-2) var(--sp-8);
}

.lyrics-item .col-memo {
    display: flex;
    flex-direction: row;
    padding: var(--sp-2) var(--sp-4);
    align-items: center;
    position: relative;
}

.clear-memo-btn {
    opacity: 0;
    pointer-events: none;
    transition: all var(--transition-fast);
    font-size: 0.65rem !important;
    width: 20px !important;
    height: 20px !important;
    padding: 0 !important;
    background: var(--surface-active) !important;
    border: 1px solid var(--border) !important;
    border-radius: 50% !important;
    color: var(--text-tertiary) !important;
    display: flex !important;
    align-items: center;
    justify-content: center;
    order: -1;
    margin-right: 4px;
    flex-shrink: 0;
}

.lyrics-item:hover .clear-memo-btn,
.lyrics-item.active .clear-memo-btn {
    opacity: 0.4;
    pointer-events: auto;
}

.clear-memo-btn:hover {
    opacity: 1 !important;
    color: var(--danger) !important;
    border-color: var(--danger-light) !important;
}

.lyrics-item:hover {
    background: var(--lyrics-hover-bg);
}

.lyrics-item.active {
    background: var(--lyrics-active-bg);
    border-left: 3px solid var(--primary);
    padding-left: calc(var(--sp-10) - 3px);
}

.lyrics-item.has-memo {
    border-right: 3px solid var(--warning);
    padding-right: calc(var(--sp-10) - 3px);
}

.lyrics-item-index {
    font-size: 0.65rem;
    font-family: var(--font-mono);
    color: var(--text-tertiary);
    min-width: 20px;
    text-align: right;
    flex-shrink: 0;
}

.lyrics-item-timestamp {
    font-size: 0.72rem;
    font-family: var(--font-mono);
    font-weight: 500;
    color: var(--timestamp-text);
    background: var(--timestamp-bg);
    padding: var(--sp-2) var(--sp-6);
    border-radius: var(--radius-sm);
    min-width: 48px;
    text-align: center;
    flex-shrink: 0;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.lyrics-item-timestamp:hover {
    filter: brightness(1.1);
    transform: scale(1.05);
}

.lyrics-item-timestamp.empty {
    background: transparent;
    border: 1px dashed var(--border);
    color: var(--text-tertiary);
}

.lyrics-item-text {
    flex: 1;
    font-size: 0.85rem;
    color: var(--text-primary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.lyrics-item-actions {
    display: flex;
    gap: var(--sp-4);
    opacity: 0;
    transition: opacity var(--transition-fast);
}

.lyrics-item:hover .lyrics-item-actions,
.lyrics-item.active .lyrics-item-actions {
    opacity: 1;
}

.lyrics-item-action-btn {
    background: transparent;
    border: none;
    color: var(--text-tertiary);
    cursor: pointer;
    font-size: 1.15rem;
    padding: var(--sp-2) var(--sp-4);
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
}

.lyrics-item-action-btn:hover {
    background: var(--border);
    color: var(--text-primary);
}

.lyrics-item-memo-indicator {
    font-size: 0.7rem;
    color: var(--warning);
    flex-shrink: 0;
}

.resizer {
    width: 8px;
    cursor: col-resize;
    flex-shrink: 0;
    transition: background var(--transition-fast);
    border-radius: var(--radius-sm);
    display: flex;
    justify-content: center;
    align-items: center;
    margin: 0 calc(var(--sp-2) * -1);
    /* subtle visual overlap */
    z-index: var(--z-dropdown);
}

.resizer::after {
    content: '';
    width: 3px;
    height: 40px;
    background: var(--border);
    border-radius: 2px;
    transition: background var(--transition-fast);
}

.resizer:hover,
.resizer.resizing {
    background: var(--primary-light);
}

.resizer:hover::after,
.resizer.resizing::after {
    background: var(--primary);
}

/* Unified List & Memo Layout */
.unified-list {
    display: flex;
    flex-direction: column;
    flex: 1;
    overflow: hidden;
    --lyric-width: 50%;
}

.list-headers {
    display: flex;
    border-bottom: 2px solid var(--border);
    background: var(--surface);
    font-size: 0.8rem;
    font-weight: bold;
    color: var(--text-secondary);
    align-items: center;
}

.col-lyric {
    width: var(--lyric-width);
    padding: var(--sp-4) var(--sp-8);
    flex-shrink: 0;
    box-sizing: border-box;
}

.col-memo {
    flex: 1;
    padding: var(--sp-4) var(--sp-8);
    box-sizing: border-box;
}

.unified-memo-input {
    flex: 1;
    width: 100%;
    background: transparent;
    border: 1px dashed transparent;
    color: var(--text-primary);
    font-size: 0.85rem;
    resize: vertical;
    padding: var(--sp-2);
    border-radius: var(--radius-sm);
    font-family: inherit;
    line-height: 1.4;
    transition: all var(--transition-fast);
}

.unified-memo-input:focus {
    border-color: var(--primary);
    outline: none;
    background: var(--input-bg);
}

.unified-memo-input:not(:placeholder-shown) {
    border: 1px dashed transparent;
    background: var(--memo-highlight);
}

/* ============================================
   Bottom: Control Bar
   ============================================ */
.control-bar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--sp-6) var(--sp-12);
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    flex-shrink: 0;
    min-height: 44px;
    box-shadow: var(--shadow-sm);
}

.control-left {
    display: flex;
    align-items: center;
    gap: var(--sp-6);
}

.control-center {
    display: flex;
    align-items: center;
    gap: var(--sp-10);
}

.control-right {
    display: flex;
    align-items: center;
    gap: var(--sp-8);
}

/* Time Display */
.time-display {
    font-family: var(--font-mono);
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-primary);
    padding: var(--sp-4) var(--sp-8);
    background: var(--input-bg);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    min-width: 100px;
    text-align: center;
}

/* Volume Controls */
.volume-controls {
    display: flex;
    align-items: center;
    gap: var(--sp-8);
}

.volume-group {
    display: flex;
    align-items: center;
    gap: var(--sp-4);
    font-size: 0.72rem;
    color: var(--text-tertiary);
}

.volume-group label {
    min-width: 32px;
}

.volume-slider {
    -webkit-appearance: none;
    appearance: none;
    width: 60px;
    height: 4px;
    background: var(--surface-active);
    border-radius: 2px;
    outline: none;
    cursor: pointer;
}

.volume-slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--primary);
    cursor: pointer;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.2);
}

/* ============================================
   Buttons
   ============================================ */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--sp-4);
    padding: var(--sp-4) var(--sp-10);
    border: 1px solid transparent;
    border-radius: var(--radius-md);
    font-family: var(--font-primary);
    font-size: 0.78rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
    white-space: nowrap;
    outline: none;
}

.btn:active {
    transform: scale(0.97);
}

.btn-primary {
    background: var(--primary);
    color: #FFFFFF;
    box-shadow: 0 2px 4px rgba(59, 130, 246, 0.3);
}

.btn-primary:hover {
    background: var(--primary-hover);
    box-shadow: 0 4px 8px rgba(59, 130, 246, 0.4);
    transform: translateY(-1px);
}

.btn-secondary {
    background: var(--surface);
    color: var(--text-primary);
    border-color: var(--border);
}

.btn-secondary:hover {
    background: var(--surface-hover);
    border-color: var(--primary-border);
}

.btn-ghost {
    background: transparent;
    color: var(--text-secondary);
}

.btn-ghost:hover {
    background: var(--surface-hover);
    color: var(--text-primary);
}

.btn-danger {
    background: var(--danger-light);
    color: var(--danger);
    border-color: transparent;
}

.btn-danger:hover {
    background: var(--danger);
    color: #FFFFFF;
}

.btn-icon {
    width: 32px;
    height: 32px;
    padding: 0;
    border-radius: var(--radius-md);
}

.btn-play {
    width: 36px;
    height: 36px;
    padding: 0;
    border-radius: 50%;
    background: var(--primary);
    color: #FFFFFF;
    font-size: 1rem;
    box-shadow: 0 2px 8px rgba(59, 130, 246, 0.4);
}

.btn-play:hover {
    background: var(--primary-hover);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.5);
    transform: scale(1.08);
}

.btn-stamp {
    background: var(--success-light);
    color: var(--success);
    border-color: transparent;
    font-weight: 600;
}

.btn-stamp:hover {
    background: var(--success);
    color: #FFFFFF;
}

.btn-copy {
    background: linear-gradient(135deg, var(--primary), var(--primary-hover));
    color: #FFFFFF;
    font-weight: 600;
    box-shadow: 0 2px 8px rgba(59, 130, 246, 0.3);
}

.btn-copy:hover {
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.5);
    transform: translateY(-1px);
}

.btn-copy.copied {
    background: var(--success);
    box-shadow: 0 2px 8px rgba(34, 197, 94, 0.3);
}

/* Small button variant */
.btn-sm {
    padding: var(--sp-2) var(--sp-6);
    font-size: 0.72rem;
}

/* ============================================
   Toast / Notification
   ============================================ */
.toast-container {
    position: fixed;
    bottom: 60px;
    right: 16px;
    z-index: var(--z-tooltip);
    display: flex;
    flex-direction: column;
    gap: var(--sp-6);
}

.toast {
    padding: var(--sp-8) var(--sp-16);
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    font-size: 0.8rem;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: var(--sp-8);
    animation: toast-in 0.3s ease forwards;
    max-width: 320px;
}

.toast.toast-success {
    border-left: 3px solid var(--success);
}

.toast.toast-error {
    border-left: 3px solid var(--danger);
}

.toast.toast-info {
    border-left: 3px solid var(--primary);
}

.toast.toast-out {
    animation: toast-out 0.3s ease forwards;
}

@keyframes toast-in {
    from {
        opacity: 0;
        transform: translateX(20px);
    }

    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes toast-out {
    from {
        opacity: 1;
        transform: translateX(0);
    }

    to {
        opacity: 0;
        transform: translateX(20px);
    }
}

/* ============================================
   Modal / Restore Dialog
   ============================================ */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--overlay);
    z-index: var(--z-modal);
    display: flex;
    align-items: center;
    justify-content: center;
    animation: fade-in 0.2s ease;
}

.modal {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-lg);
    padding: var(--sp-24);
    max-width: 400px;
    width: 90%;
    animation: modal-in 0.3s ease;
}

.modal h2 {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: var(--sp-8);
}

.modal p {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-bottom: var(--sp-16);
    line-height: 1.6;
}

.modal-actions {
    display: flex;
    gap: var(--sp-8);
    justify-content: flex-end;
}

@keyframes fade-in {
    from {
        opacity: 0;
    }

    to {
        opacity: 1;
    }
}

@keyframes modal-in {
    from {
        opacity: 0;
        transform: scale(0.95) translateY(10px);
    }

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

/* ============================================
   Keyboard Shortcut Badge
   ============================================ */
.kbd {
    display: inline-flex;
    align-items: center;
    padding: 1px 5px;
    font-family: var(--font-mono);
    font-size: 0.65rem;
    background: var(--surface-active);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    color: var(--text-tertiary);
    box-shadow: 0 1px 0 var(--border);
}

/* ============================================
   Utilities
   ============================================ */
.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip: rect(0 0 0 0);
    white-space: nowrap;
}

.text-mono {
    font-family: var(--font-mono);
}

.text-muted {
    color: var(--text-tertiary);
}

/* ============================================
   Responsive / Density Adjustments
   ============================================ */
@media (max-height: 768px) {
    html {
        font-size: 13px;
    }

    #app {
        padding: var(--sp-4);
        gap: var(--sp-4);
    }

    .media-area {
        gap: var(--sp-4);
    }

    .work-area {
        gap: var(--sp-4);
    }


    .memo-panel {
        width: 320px;
    }

    .waveform-track {
        min-height: 50px;
    }
}

@media (max-height: 650px) {
    html {
        font-size: 12px;
    }

    .header-bar,
    .control-bar {
        min-height: 34px;
        padding: var(--sp-4) var(--sp-10);
    }
}

/* File name displayed on tracks */
.track-file-info {
    position: absolute;
    top: var(--sp-4);
    right: var(--sp-8);
    font-size: 0.65rem;
    color: var(--text-tertiary);
    font-family: var(--font-mono);
    z-index: var(--z-base);
    background: var(--surface);
    padding: var(--sp-2) var(--sp-6);
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
    pointer-events: none;
    max-width: 150px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

/* Remove track button */
.track-remove-btn {
    position: absolute;
    top: var(--sp-4);
    right: var(--sp-8);
    z-index: var(--z-dropdown);
    width: 20px;
    height: 20px;
    padding: 0;
    font-size: 0.65rem;
    border-radius: 50%;
    background: var(--danger-light);
    color: var(--danger);
    border: none;
    cursor: pointer;
    display: none;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
}

.waveform-track:hover .track-remove-btn {
    display: flex;
}

.track-remove-btn:hover {
    background: var(--danger);
    color: #fff;
}

/* Lyrics edit mode toggle */
.lyrics-mode-tabs {
    display: inline-flex;
    background: var(--surface-active);
    border-radius: var(--radius-lg);
    padding: 3px;
    border: 1px solid var(--border);
    box-shadow: inset 0 1px 2px rgba(0, 0, 0, 0.05);
}

.lyrics-mode-tab {
    padding: 6px 14px;
    font-size: 0.78rem;
    font-weight: 600;
    color: var(--text-secondary);
    background: transparent;
    border: none;
    border-radius: calc(var(--radius-lg) - 2px);
    cursor: pointer;
    transition: all var(--transition-normal);
    font-family: var(--font-primary);
    white-space: nowrap;
    line-height: 1;
}

.lyrics-mode-tab.active {
    background: var(--surface);
    color: var(--primary);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.lyrics-mode-tab:hover:not(.active) {
    color: var(--text-primary);
    background: rgba(0, 0, 0, 0.02);
}

/* Separator in controls */
.control-separator {
    width: 1px;
    height: 20px;
    background: var(--border);
}

/* Header Project Actions */
.header-project-actions {
    position: relative;
    z-index: var(--z-modal);
    /* Ensure it's above any other header elements */
}

.header-project-actions .btn {
    border: 1px solid var(--border);
    background: var(--surface);
    transition: all var(--transition-fast);
    cursor: pointer !important;
}

.header-project-actions .btn:hover {
    background: var(--surface-active);
    border-color: var(--primary-border);
    color: var(--primary);
    transform: translateY(-1px);
}

/* Autosave indicator */
.autosave-indicator {
    display: flex;
    align-items: center;
    gap: var(--sp-4);
    font-size: 0.7rem;
    color: var(--text-tertiary);
}

.autosave-dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--success);
    animation: pulse-dot 2s ease-in-out infinite;
}

@keyframes pulse-dot {

    0%,
    100% {
        opacity: 1;
    }

    50% {
        opacity: 0.4;
    }
}

/* Tooltip */
[data-tooltip]::after {
    content: attr(data-tooltip);
    position: absolute;
    bottom: 100%;
    left: 50%;
    transform: translateX(-50%);
    padding: var(--sp-4) var(--sp-8);
    background: var(--text-primary);
    color: var(--bg);
    font-size: 0.7rem;
    border-radius: var(--radius-sm);
    white-space: nowrap;
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition-fast), transform var(--transition-fast);
    margin-bottom: 6px;
    z-index: var(--z-tooltip);
    box-shadow: var(--shadow-md);
}

[data-tooltip]:hover::after {
    opacity: 1;
    transform: translateX(-50%) translateY(-2px);
}

/* Tooltips in Header should go BELOW to avoid being cut off */
.header-bar [data-tooltip]::after {
    bottom: auto;
    top: 100%;
    margin-bottom: 0;
    margin-top: 6px;
}

.header-bar [data-tooltip]:hover::after {
    transform: translateX(-50%) translateY(2px);
}

/* Creator Section */
.creator-section {
    display: flex;
    align-items: center;
    gap: var(--sp-8);
    position: relative;
    cursor: pointer;
}

.creator-icon-wrap {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    border: 2px solid var(--primary);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: transform 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275), box-shadow 0.4s ease;
}

.creator-section:hover .creator-icon-wrap {
    transform: scale(1.8) translateY(-4px);
    box-shadow: 0 6px 16px rgba(0, 0, 0, 0.25);
}

.creator-icon {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.creator-bubble {
    position: absolute;
    left: 40px;
    background: var(--surface);
    border: 1px solid var(--border);
    padding: var(--sp-4) var(--sp-12);
    border-radius: var(--radius-lg);
    font-size: 0.75rem;
    white-space: nowrap;
    opacity: 0;
    transform: translateX(-10px);
    transition: all var(--transition-normal);
    pointer-events: none;
    box-shadow: var(--shadow-md);
    color: var(--text-primary);
}

.creator-bubble::before {
    content: '';
    position: absolute;
    left: -6px;
    top: 50%;
    transform: translateY(-50%) rotate(45deg);
    width: 10px;
    height: 10px;
    background: var(--surface);
    border-left: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
}

.creator-section:hover .creator-bubble {
    opacity: 1;
    transform: translateX(0);
}

.creator-name {
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--text-secondary);
}

.footer-bubble {
    left: 0 !important;
    bottom: 120% !important;
    top: auto !important;
    transform: translateY(10px) !important;
}

.creator-section:hover .footer-bubble {
    transform: translateY(0) !important;
}

.footer-bubble::before {
    left: 10px !important;
    top: 100% !important;
    transform: translateY(-5px) rotate(45deg) !important;
    border-left: none !important;
    border-bottom: 1px solid var(--border) !important;
    border-right: 1px solid var(--border) !important;
}

/* Lyric Selection List */
#selection-list {
    margin: 0;
    list-style: none;
    padding: 0;
}

#selection-list li {
    padding: var(--sp-4) var(--sp-6);
    border-bottom: 1px solid var(--border);
    cursor: pointer;
    transition: background 0.2s;
    display: flex;
    flex-direction: column;
    gap: 2px;
}

#selection-list li:last-child {
    border-bottom: none;
}

#selection-list li:hover {
    background: var(--surface-active);
}

#selection-list li .item-title {
    font-weight: bold;
    color: var(--primary);
}

#selection-list li .item-artist {
    font-size: 0.8rem;
    color: var(--text-secondary);
}