/* ============================================
   CSS Reset & Base Styles
   ============================================ */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Color Palette */
    --bg-primary: #0f0f1e;
    --bg-secondary: #1a1a2e;
    --bg-tertiary: #16213e;
    --accent-primary: #e94560;
    --accent-secondary: #ff6b6b;
    --accent-glow: rgba(233, 69, 96, 0.4);
    --text-primary: #ffffff;
    --text-secondary: #b8b8b8;
    --text-muted: #6c757d;
    --border-color: #2d3748;
    --pad-default: #2a2d3a;
    --pad-hover: #363945;
    --pad-active: #e94560;
    --step-active: #4a4e69;
    --step-playing: #00ff88;
    --success: #00ff88;
    --warning: #ffd93d;

    /* Typography */
    --font-primary: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue', sans-serif;
    --font-mono: 'SF Mono', 'Monaco', 'Inconsolata', 'Fira Code', 'Fira Mono', 'Roboto Mono', monospace;

    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-xxl: 3rem;

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

    /* Shadows */
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.5);
    --shadow-glow: 0 0 20px var(--accent-glow);

    /* Transitions */
    --transition-fast: 0.15s ease;
    --transition-medium: 0.3s ease;
}

/* ============================================
   Base Typography & Layout
   ============================================ */
html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-primary);
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* ============================================
   Header
   ============================================ */
.header {
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    padding: var(--spacing-md) 0;
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(10px);
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--accent-primary);
    letter-spacing: -0.5px;
}

.nav {
    display: flex;
    gap: var(--spacing-lg);
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.95rem;
    transition: color var(--transition-fast);
}

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

/* ============================================
   Main Content
   ============================================ */
.main {
    padding: var(--spacing-xl) 0;
    min-height: calc(100vh - 200px);
}

/* ============================================
   Hero Section
   ============================================ */
.hero {
    text-align: center;
    margin-bottom: var(--spacing-xl);
    padding: var(--spacing-lg) 0;
}

.hero-title {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: var(--spacing-md);
    background: linear-gradient(135deg, var(--accent-primary) 0%, var(--accent-secondary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.15rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* ============================================
   Drum Machine Interface
   ============================================ */
.drum-machine {
    background: var(--bg-secondary);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    box-shadow: var(--shadow-lg);
    margin-bottom: var(--spacing-xxl);
    border: 1px solid var(--border-color);
}

/* ============================================
   Transport Controls
   ============================================ */
.controls-section {
    margin-bottom: var(--spacing-xl);
}

.transport-controls {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: var(--spacing-md);
}

.pattern-controls {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    flex-wrap: wrap;
}

/* ============================================
   Buttons
   ============================================ */
.btn {
    font-family: var(--font-primary);
    font-weight: 600;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
    outline: none;
    position: relative;
    overflow: hidden;
}

.btn:active {
    transform: scale(0.95);
}

.btn-primary {
    background: linear-gradient(135deg, var(--accent-primary) 0%, var(--accent-secondary) 100%);
    color: var(--text-primary);
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    box-shadow: var(--shadow-glow);
    transform: translateY(-2px);
}

.btn-primary:active {
    transform: translateY(0);
}

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

.btn-secondary:hover:not(:disabled) {
    background: var(--pad-hover);
    border-color: var(--accent-primary);
}

.btn-secondary:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

.btn-large {
    padding: var(--spacing-md) var(--spacing-xxl);
    font-size: 1.15rem;
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.btn-small {
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: 1.25rem;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.btn-icon {
    font-size: 1rem;
}

/* Stop and Clear buttons */
#stopBtn,
#clearBtn {
    padding: var(--spacing-md) var(--spacing-lg);
    font-size: 1rem;
}

/* Save, Load, and Share Pattern buttons */
.btn-save,
.btn-load,
.btn-share {
    padding: var(--spacing-sm) var(--spacing-lg);
    font-size: 0.95rem;
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border: 2px solid var(--border-color);
    transition: all var(--transition-fast);
}

.btn-save:hover {
    border-color: var(--success);
    background: rgba(0, 255, 136, 0.1);
    transform: translateY(-2px);
}

.btn-load:hover {
    border-color: #4a9eff;
    background: rgba(74, 158, 255, 0.1);
    transform: translateY(-2px);
}

.btn-share:hover {
    border-color: #ff9d00;
    background: rgba(255, 157, 0, 0.1);
    transform: translateY(-2px);
}

.btn-save:active,
.btn-load:active,
.btn-share:active {
    transform: scale(0.95);
}

/* ============================================
   Genre Beat Generator
   ============================================ */
.genre-generator {
    margin-bottom: var(--spacing-xl);
    padding: var(--spacing-lg);
    background: linear-gradient(135deg, var(--bg-tertiary) 0%, var(--bg-secondary) 100%);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
}

.genre-header {
    text-align: center;
    margin-bottom: var(--spacing-md);
}

.genre-title {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
}

.genre-subtitle {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin: 0;
}

.genre-controls {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    align-items: center;
    flex-wrap: wrap;
}

.genre-select {
    flex: 1;
    min-width: 200px;
    max-width: 300px;
    padding: var(--spacing-md) var(--spacing-lg);
    font-size: 1rem;
    font-family: var(--font-primary);
    font-weight: 600;
    background: var(--bg-primary);
    color: var(--text-primary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
    outline: none;
}

.genre-select:hover {
    border-color: var(--accent-primary);
    background: var(--bg-tertiary);
}

.genre-select:focus {
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px var(--accent-glow);
}

.genre-select option {
    background: var(--bg-secondary);
    color: var(--text-primary);
    padding: var(--spacing-sm);
}

.btn-generate {
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: 1rem;
    font-weight: 700;
    background: linear-gradient(135deg, #9d50bb 0%, #6e48aa 100%);
    color: var(--text-primary);
    border: none;
    box-shadow: var(--shadow-md);
    transition: all var(--transition-fast);
}

.btn-generate:hover {
    background: linear-gradient(135deg, #b060d1 0%, #8458ba 100%);
    transform: translateY(-2px);
    box-shadow: 0 0 20px rgba(157, 80, 187, 0.4);
}

.btn-generate:active {
    transform: scale(0.95);
}

.btn-generate.generating {
    animation: pulse-generate 0.8s ease infinite;
}

@keyframes pulse-generate {
    0%, 100% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.05);
    }
}

/* ============================================
   Preset Patterns Library
   ============================================ */
.preset-patterns {
    margin-bottom: var(--spacing-xl);
    padding: var(--spacing-lg);
    background: linear-gradient(135deg, var(--bg-tertiary) 0%, var(--bg-secondary) 100%);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
}

.preset-header {
    text-align: center;
    margin-bottom: var(--spacing-md);
}

.preset-title {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
}

.preset-subtitle {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin: 0;
}

.preset-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: var(--spacing-md);
}

.preset-card {
    padding: var(--spacing-md);
    background: var(--bg-primary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-xs);
    text-align: center;
}

.preset-card:hover {
    border-color: var(--warning);
    background: var(--bg-tertiary);
    transform: translateY(-3px);
    box-shadow: 0 0 15px rgba(255, 217, 61, 0.3);
}

.preset-card:active {
    transform: scale(0.95);
}

.preset-name {
    font-size: 1rem;
    font-weight: 700;
    color: var(--text-primary);
}

.preset-desc {
    font-size: 0.75rem;
    color: var(--text-secondary);
    line-height: 1.3;
}

/* ============================================
   BPM Controls
   ============================================ */
.bpm-section {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
    padding: var(--spacing-lg);
    background: var(--bg-tertiary);
    border-radius: var(--radius-lg);
}

.bpm-display-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-sm);
}

.bpm-label {
    font-size: 0.9rem;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 1px;
    font-weight: 600;
}

.bpm-display {
    display: flex;
    align-items: baseline;
    gap: var(--spacing-sm);
    font-family: var(--font-mono);
}

#bpmValue {
    font-size: 3rem;
    font-weight: 700;
    color: var(--accent-primary);
    line-height: 1;
}

.bpm-unit {
    font-size: 1rem;
    color: var(--text-secondary);
    font-weight: 600;
}

.bpm-controls {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    width: 100%;
    max-width: 500px;
}

.bpm-slider {
    flex: 1;
    height: 6px;
    border-radius: 3px;
    background: var(--bg-primary);
    outline: none;
    -webkit-appearance: none;
    appearance: none;
}

.bpm-slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--accent-primary);
    cursor: pointer;
    box-shadow: var(--shadow-md);
    transition: transform var(--transition-fast);
}

.bpm-slider::-webkit-slider-thumb:hover {
    transform: scale(1.2);
}

.bpm-slider::-moz-range-thumb {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--accent-primary);
    cursor: pointer;
    border: none;
    box-shadow: var(--shadow-md);
    transition: transform var(--transition-fast);
}

.bpm-slider::-moz-range-thumb:hover {
    transform: scale(1.2);
}

.btn-tap {
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: 1rem;
    background: var(--bg-primary);
    color: var(--text-primary);
    border: 2px solid var(--border-color);
    position: relative;
    transition: all var(--transition-fast);
    min-width: 150px;
}

.btn-tap:hover {
    border-color: var(--accent-primary);
    background: var(--bg-tertiary);
    transform: translateY(-2px);
}

.btn-tap.tapping {
    border-color: var(--success);
    background: var(--accent-primary);
    color: var(--text-primary);
    transform: scale(0.95);
    box-shadow: 0 0 20px rgba(0, 255, 136, 0.4);
}

.btn-tap::after {
    content: attr(data-taps);
    position: absolute;
    bottom: -24px;
    left: 50%;
    transform: translateX(-50%);
    font-size: 0.75rem;
    color: var(--success);
    white-space: nowrap;
    opacity: 0;
    transition: opacity var(--transition-fast);
}

.btn-tap[data-taps]::after {
    opacity: 1;
}

/* ============================================
   Step Sequencer
   ============================================ */
.sequencer {
    margin-bottom: var(--spacing-xl);
    background: var(--bg-tertiary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    overflow-x: auto;
}

.sequencer-header {
    margin-bottom: var(--spacing-md);
}

.step-numbers {
    display: flex;
    align-items: center;
    margin-bottom: var(--spacing-sm);
}

.step-label {
    width: 100px;
    font-size: 0.85rem;
    color: var(--text-secondary);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.step-number-row {
    display: grid;
    grid-template-columns: repeat(16, 1fr);
    gap: 4px;
    flex: 1;
}

.step-number-row span {
    text-align: center;
    font-size: 0.75rem;
    color: var(--text-muted);
    font-family: var(--font-mono);
}

.sequencer-grid {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.sequencer-row {
    display: flex;
    align-items: center;
    gap: 6px;
}

.sequencer-label {
    width: 100px;
    font-size: 0.85rem;
    color: var(--text-secondary);
    font-weight: 600;
    display: flex;
    flex-direction: column;
    gap: 2px;
    justify-content: center;
}

.drum-name {
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.drum-key-indicator {
    display: inline-block;
    padding: 2px 6px;
    background: var(--bg-primary);
    color: var(--text-muted);
    font-size: 0.65rem;
    font-family: var(--font-mono);
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-color);
    text-align: center;
    min-width: 20px;
    font-weight: 700;
    transition: all var(--transition-fast);
}

.sequencer-row.key-pressed .drum-key-indicator {
    background: var(--accent-primary);
    color: var(--text-primary);
    border-color: var(--accent-primary);
    box-shadow: 0 0 8px var(--accent-glow);
    transform: scale(1.1);
}

.sequencer-row.key-pressed .drum-name {
    color: var(--accent-primary);
}

.sequencer-steps {
    display: grid;
    grid-template-columns: repeat(16, 1fr);
    gap: 4px;
    flex: 1;
}

.step {
    aspect-ratio: 1;
    min-width: 30px;
    background: var(--bg-primary);
    border: 2px solid transparent;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.step:hover {
    background: var(--pad-hover);
    border-color: var(--accent-primary);
}

.step.active {
    background: var(--accent-primary);
    border-color: var(--accent-primary);
    box-shadow: 0 0 10px var(--accent-glow);
}

.step.playing {
    box-shadow: 0 0 15px var(--step-playing), inset 0 0 10px rgba(255, 255, 255, 0.3);
    border-color: var(--step-playing);
}

.step.active.playing {
    background: var(--accent-secondary);
    box-shadow: 0 0 20px var(--accent-glow), inset 0 0 10px rgba(255, 255, 255, 0.3);
}

/* Highlight every 4th step */
.step:nth-child(4n+1) {
    border-left: 2px solid var(--border-color);
}

/* Painting animation for drag-to-paint */
.step.painting {
    animation: paint-flash 0.1s ease;
}

@keyframes paint-flash {
    0%, 100% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.15);
        box-shadow: 0 0 15px var(--accent-primary);
    }
}

/* Quick action buttons */
.quick-actions {
    display: flex;
    gap: 2px;
    margin-top: 4px;
    flex-wrap: wrap;
}

.quick-action-btn {
    padding: 2px 6px;
    font-size: 0.65rem;
    font-family: var(--font-mono);
    font-weight: 700;
    background: var(--bg-primary);
    color: var(--text-muted);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
    min-width: 20px;
    text-align: center;
}

.quick-action-btn:hover {
    background: var(--pad-hover);
    color: var(--text-primary);
    border-color: var(--accent-primary);
    transform: translateY(-1px);
}

.quick-action-btn:active {
    transform: scale(0.9);
}

.quick-action-btn:last-child {
    color: var(--accent-primary);
}

/* ============================================
   Collapsible Sections
   ============================================ */
.collapsible-section {
    position: relative;
}

.section-toggle {
    width: 100%;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-md);
    background: transparent;
    border: none;
    cursor: pointer;
    transition: background var(--transition-fast);
    text-align: left;
}

.section-toggle:hover {
    background: rgba(255, 255, 255, 0.05);
}

.section-toggle h3 {
    margin: 0;
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
}

.toggle-icon {
    font-size: 1.2rem;
    transition: transform var(--transition-medium);
    color: var(--accent-primary);
    font-weight: bold;
}

.section-toggle[aria-expanded="false"] .toggle-icon {
    transform: rotate(-90deg);
}

.section-content {
    overflow: hidden;
    transition: max-height var(--transition-medium), opacity var(--transition-medium);
    max-height: 2000px;
    opacity: 1;
}

.section-content.collapsed {
    max-height: 0;
    opacity: 0;
}

/* ============================================
   Drum Pads
   ============================================ */
.drum-pads {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-md);
}

.drum-pad {
    aspect-ratio: 1;
    background: var(--pad-default);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    cursor: pointer;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    font-weight: 600;
    color: var(--text-primary);
    transition: all var(--transition-fast);
    position: relative;
    overflow: hidden;
    min-height: 100px;
}

.drum-pad::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, var(--accent-primary) 0%, var(--accent-secondary) 100%);
    opacity: 0;
    transition: opacity var(--transition-fast);
}

.drum-pad:hover {
    border-color: var(--accent-primary);
    transform: translateY(-4px);
    box-shadow: var(--shadow-glow);
}

.drum-pad:active,
.drum-pad.hitting {
    transform: scale(0.95);
    border-color: var(--accent-primary);
}

.drum-pad.hitting::before {
    opacity: 0.3;
}

.pad-name,
.pad-key {
    position: relative;
    z-index: 1;
}

.pad-name {
    font-size: 1rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.pad-key {
    font-size: 0.75rem;
    color: var(--text-muted);
    background: var(--bg-primary);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-sm);
    font-family: var(--font-mono);
}

/* Custom Sample Pads */
.custom-pad {
    border: 2px dashed var(--border-color);
}

.custom-pad.has-sample {
    border-style: solid;
    border-color: var(--success);
}

.custom-pad.selected {
    border-color: var(--warning);
    border-width: 3px;
}

.record-indicator {
    position: absolute;
    top: 8px;
    right: 8px;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--success);
    opacity: 0;
    z-index: 2;
}

.custom-pad.has-sample .record-indicator {
    opacity: 1;
}

/* ============================================
   Sample Recording Controls
   ============================================ */
.recording-controls {
    margin-top: var(--spacing-xl);
    padding: var(--spacing-lg);
    background: var(--bg-tertiary);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
}

.recording-info {
    text-align: center;
    margin-bottom: var(--spacing-md);
}

.recording-title {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
}

.recording-subtitle {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin: 0;
}

.recording-buttons {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: var(--spacing-md);
}

.btn-small-rec {
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: 0.9rem;
}

.btn-small-rec.selected {
    background: var(--warning);
    border-color: var(--warning);
    color: var(--bg-primary);
}

.btn-record {
    padding: var(--spacing-md) var(--spacing-lg);
    font-size: 1rem;
    background: var(--bg-primary);
    color: var(--text-primary);
    border: 2px solid var(--border-color);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.btn-record:hover:not(:disabled) {
    border-color: var(--accent-primary);
    background: var(--bg-tertiary);
}

.btn-record:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.btn-record.recording {
    border-color: var(--accent-primary);
    background: var(--accent-primary);
    animation: pulse-record 1s ease infinite;
}

#recordIcon {
    font-size: 1.2rem;
}

.btn-record.recording #recordIcon {
    color: var(--text-primary);
}

@keyframes pulse-record {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.7;
    }
}

.recording-status {
    text-align: center;
    min-height: 24px;
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.recording-status.recording {
    color: var(--accent-primary);
    font-weight: 600;
}

.recording-status.success {
    color: var(--success);
    font-weight: 600;
}

.recording-status.error {
    color: var(--accent-primary);
    font-weight: 600;
}

/* ============================================
   Info Section
   ============================================ */
.info-section {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-xxl);
}

.info-card {
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    border: 1px solid var(--border-color);
}

.info-card h2 {
    font-size: 1.75rem;
    margin-bottom: var(--spacing-md);
    color: var(--accent-primary);
}

.info-card h3 {
    font-size: 1.25rem;
    margin-top: var(--spacing-lg);
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
}

.info-card p {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
    line-height: 1.7;
}

.info-card ul {
    list-style: none;
    padding-left: 0;
}

.info-card ul li {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-sm);
    padding-left: var(--spacing-lg);
    position: relative;
    line-height: 1.7;
}

.info-card ul li::before {
    content: '▸';
    position: absolute;
    left: 0;
    color: var(--accent-primary);
    font-weight: bold;
}

.feature-list li strong {
    color: var(--text-primary);
}

.text-link {
    color: var(--accent-primary);
    text-decoration: none;
    font-weight: 600;
    transition: color var(--transition-fast);
}

.text-link:hover {
    color: var(--accent-secondary);
    text-decoration: underline;
}

/* ============================================
   Footer
   ============================================ */
.footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    padding: var(--spacing-xxl) 0 var(--spacing-lg);
    margin-top: auto;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
}

.footer-section h3 {
    font-size: 1.1rem;
    margin-bottom: var(--spacing-md);
    color: var(--accent-primary);
}

.footer-section p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.6;
}

.footer-links {
    list-style: none;
}

.footer-links li {
    margin-bottom: var(--spacing-sm);
}

.footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: color var(--transition-fast);
    font-size: 0.95rem;
}

.footer-links a:hover {
    color: var(--accent-primary);
}

.footer-bottom {
    text-align: center;
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--border-color);
}

.footer-bottom p {
    color: var(--text-muted);
    font-size: 0.9rem;
}

/* ============================================
   Responsive Design
   ============================================ */

/* Tablets */
@media (max-width: 768px) {
    :root {
        --spacing-xl: 1.5rem;
        --spacing-xxl: 2rem;
    }

    .hero-title {
        font-size: 2rem;
    }

    .hero-subtitle {
        font-size: 1rem;
    }

    .drum-machine {
        padding: var(--spacing-lg);
    }

    .drum-pads {
        grid-template-columns: repeat(2, 1fr);
    }

    .step-label,
    .sequencer-label {
        width: 100px;
        font-size: 0.75rem;
    }

    .drum-key-indicator {
        font-size: 0.6rem;
        padding: 1px 4px;
        min-width: 18px;
    }

    /* Smaller quick-fill buttons on tablet */
    .quick-action-btn {
        font-size: 0.6rem;
        padding: 2px 4px;
        min-width: 18px;
    }

    .step {
        min-width: 28px;
    }

    /* Allow horizontal scrolling on tablet */
    .sequencer {
        overflow-x: auto;
    }

    .footer-content {
        grid-template-columns: 1fr;
    }

    #bpmValue {
        font-size: 2.5rem;
    }
}

/* Mobile Phones */
@media (max-width: 480px) {
    .container {
        padding: 0 var(--spacing-sm);
    }

    .logo {
        font-size: 1.25rem;
    }

    /* Sticky transport controls on mobile */
    .controls-section {
        position: sticky;
        top: 60px;
        z-index: 90;
        background: var(--bg-secondary);
        padding: var(--spacing-sm) 0;
        margin-bottom: var(--spacing-md);
        border-bottom: 1px solid var(--border-color);
    }

    .hero-title {
        font-size: 1.75rem;
    }

    .hero-subtitle {
        font-size: 0.95rem;
    }

    .drum-machine {
        padding: var(--spacing-md);
    }

    .transport-controls {
        width: 100%;
    }

    .pattern-controls {
        gap: var(--spacing-sm);
    }

    .btn-large {
        flex: 1;
        justify-content: center;
    }

    #stopBtn,
    #clearBtn {
        flex: 1;
    }

    /* Smaller buttons on mobile */
    #undoBtn,
    #redoBtn {
        padding: var(--spacing-sm) var(--spacing-md);
        font-size: 0.85rem;
    }

    .btn-save,
    .btn-load,
    .btn-share {
        padding: var(--spacing-sm) var(--spacing-md);
        font-size: 0.85rem;
    }

    .drum-pads {
        gap: var(--spacing-sm);
    }

    .drum-pad {
        min-height: 80px;
    }

    .pad-name {
        font-size: 0.85rem;
    }

    .step-label,
    .sequencer-label {
        width: 60px;
        font-size: 0.7rem;
    }

    /* Hide quick-fill buttons on mobile */
    .quick-actions {
        display: none;
    }

    /* Collapsible sections on mobile */
    .section-toggle {
        padding: var(--spacing-sm) var(--spacing-md);
    }

    .section-toggle h3 {
        font-size: 1rem;
    }

    .toggle-icon {
        font-size: 1rem;
    }

    /* Hide keyboard indicators on mobile (not useful on touch devices) */
    .drum-key-indicator {
        display: none;
    }

    /* Also hide keyboard hints in drum pads */
    .pad-key {
        display: none;
    }

    .step {
        min-width: 24px;
        gap: 2px;
        min-height: 40px;
    }

    /* Better sequencer scrolling on mobile */
    .sequencer {
        overflow-x: scroll;
        -webkit-overflow-scrolling: touch;
    }

    .sequencer-grid {
        min-width: 600px;
    }

    .sequencer-row {
        gap: 3px;
    }

    .sequencer-steps {
        gap: 2px;
    }

    .step-number-row {
        gap: 2px;
    }

    .step-number-row span {
        font-size: 0.65rem;
    }

    #bpmValue {
        font-size: 2rem;
    }

    .info-card {
        padding: var(--spacing-lg);
    }

    .info-card h2 {
        font-size: 1.5rem;
    }

    .info-card h3 {
        font-size: 1.1rem;
    }
}

/* ============================================
   Animations & Effects
   ============================================ */
@keyframes pulse {
    0%, 100% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.05);
    }
}

.drum-pad.hitting {
    animation: pulse 0.2s ease;
}

@keyframes glow {
    0%, 100% {
        box-shadow: 0 0 10px var(--accent-glow);
    }
    50% {
        box-shadow: 0 0 20px var(--accent-glow);
    }
}

/* ============================================
   Pattern Notification
   ============================================ */
.pattern-notification {
    position: fixed;
    top: 80px;
    left: 50%;
    transform: translateX(-50%) translateY(-100px);
    background: var(--bg-secondary);
    color: var(--text-primary);
    padding: var(--spacing-md) var(--spacing-xl);
    border-radius: var(--radius-lg);
    border: 2px solid var(--success);
    box-shadow: var(--shadow-lg);
    font-size: 1rem;
    font-weight: 600;
    opacity: 0;
    transition: all var(--transition-medium);
    z-index: 1000;
    pointer-events: none;
}

.pattern-notification.show {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
}

.pattern-notification.error {
    border-color: var(--accent-primary);
    background: var(--bg-tertiary);
}

.pattern-notification.info {
    border-color: var(--warning);
    background: var(--bg-tertiary);
}

/* ============================================
   Accessibility
   ============================================ */
.btn:focus-visible,
.drum-pad:focus-visible,
.step:focus-visible {
    outline: 2px solid var(--accent-primary);
    outline-offset: 2px;
}

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* ============================================
   Print Styles
   ============================================ */
@media print {
    .header,
    .drum-machine,
    .footer {
        display: none;
    }

    .info-section {
        display: block;
    }
}

/* ============================================
   Mobile Bottom Navigation & View Management
   ============================================ */

/* Hide bottom nav on desktop */
.mobile-bottom-nav {
    display: none;
}

/* Hide large pads container by default */
.large-pads-container {
    display: none;
}

/* Mobile view title */
.mobile-view-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--accent-primary);
    margin-bottom: var(--spacing-lg);
    text-align: center;
}

/* Large drum pads for mobile */
.large-drum-pads {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-lg);
    padding: var(--spacing-md) 0;
}

.large-drum-pads .drum-pad {
    min-height: 100px;
    font-size: 1.1rem;
}

/* Mobile-specific styles (< 480px) */
@media (max-width: 480px) {
    /* Show bottom nav on mobile */
    .mobile-bottom-nav {
        display: flex;
        position: fixed;
        bottom: 0;
        left: 0;
        right: 0;
        background: var(--bg-secondary);
        border-top: 1px solid var(--border-color);
        z-index: 100;
        padding: env(safe-area-inset-bottom, 0) 0 0 0;
        padding-bottom: env(safe-area-inset-bottom, 8px);
        box-shadow: 0 -4px 12px rgba(0, 0, 0, 0.3);
    }

    /* Nav tabs */
    .nav-tab {
        flex: 1;
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        gap: var(--spacing-xs);
        padding: var(--spacing-sm) 0;
        background: transparent;
        border: none;
        color: var(--text-secondary);
        cursor: pointer;
        transition: all var(--transition-fast);
        position: relative;
    }

    .nav-tab::before {
        content: '';
        position: absolute;
        top: 0;
        left: 10%;
        right: 10%;
        height: 3px;
        background: var(--accent-primary);
        opacity: 0;
        transition: opacity var(--transition-fast);
        border-radius: 0 0 3px 3px;
    }

    .nav-tab.active::before {
        opacity: 1;
    }

    .nav-tab.active {
        color: var(--accent-primary);
    }

    .nav-icon {
        font-size: 1.5rem;
        line-height: 1;
    }

    .nav-label {
        font-size: 0.7rem;
        font-weight: 600;
        text-transform: uppercase;
        letter-spacing: 0.5px;
    }

    /* Add bottom padding to drum-machine to account for fixed bottom nav */
    .drum-machine {
        padding-bottom: calc(70px + var(--spacing-xl));
        margin-bottom: var(--spacing-md);
    }

    /* View-specific hiding logic */
    /* When on Sequencer view (default) */
    body.mobile-view-sequencer .genre-generator,
    body.mobile-view-sequencer .preset-patterns,
    body.mobile-view-sequencer .recording-controls,
    body.mobile-view-sequencer .drum-pads,
    body.mobile-view-sequencer .pattern-controls .btn-save,
    body.mobile-view-sequencer .pattern-controls .btn-load,
    body.mobile-view-sequencer .pattern-controls .btn-share {
        display: none;
    }

    /* When on Pads view */
    body.mobile-view-pads .controls-section,
    body.mobile-view-pads .genre-generator,
    body.mobile-view-pads .preset-patterns,
    body.mobile-view-pads .bpm-section,
    body.mobile-view-pads .sequencer,
    body.mobile-view-pads .drum-pads,
    body.mobile-view-pads .recording-controls {
        display: none;
    }

    body.mobile-view-pads .large-pads-container {
        display: block;
    }

    /* When on Tools view */
    body.mobile-view-tools .controls-section,
    body.mobile-view-tools .bpm-section,
    body.mobile-view-tools .sequencer,
    body.mobile-view-tools .drum-pads {
        display: none !important;
    }

    body.mobile-view-tools .genre-generator,
    body.mobile-view-tools .preset-patterns,
    body.mobile-view-tools .recording-controls {
        display: block;
    }

    /* When on Save view */
    body.mobile-view-save .controls-section,
    body.mobile-view-save .genre-generator,
    body.mobile-view-save .preset-patterns,
    body.mobile-view-save .bpm-section,
    body.mobile-view-save .sequencer,
    body.mobile-view-save .drum-pads,
    body.mobile-view-save .recording-controls {
        display: none;
    }

    body.mobile-view-save .save-view-container {
        display: block;
    }

    /* Save view content */
    .save-view-container {
        display: none;
        padding: var(--spacing-lg);
    }

    .save-view-content {
        text-align: center;
    }

    .save-actions {
        display: flex;
        flex-direction: column;
        gap: var(--spacing-md);
        margin-bottom: var(--spacing-lg);
    }

    .save-info {
        padding: var(--spacing-md);
        background: var(--bg-tertiary);
        border-radius: var(--radius-md);
        border-left: 4px solid var(--warning);
    }

    .save-info-text {
        font-size: 0.9rem;
        color: var(--text-secondary);
        line-height: 1.6;
        margin: 0;
    }

    /* Large pads styling */
    .large-drum-pads {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-md);
    }

    .large-drum-pads .drum-pad {
        min-height: 120px;
        font-size: 1.15rem;
    }
}