/* ===========================================
   MUSIC PRODUCTION COURSE STYLES
   =========================================== */

/* Lesson Structure */
.lesson-section {
    margin-bottom: 3rem;
}

.lesson-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 2rem;
}

.lesson-number {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 2.5rem;
    height: 2.5rem;
    background: rgba(167, 139, 250, 0.1);
    border: 1px solid rgba(167, 139, 250, 0.3);
    border-radius: 50%;
    color: #A78BFA;
    font-weight: 600;
    font-size: 0.875rem;
    flex-shrink: 0;
}

.lesson-title {
    font-family: 'Nunito', sans-serif;
    font-size: 1.75rem;
    font-weight: 700;
    color: #f5f5f5;
    margin: 0;
}

/* Prose Content */
.prose-content {
    color: #a3a3a3;
    line-height: 1.75;
}

.prose-content .lead {
    font-size: 1.25rem;
    color: #d4d4d4;
    margin-bottom: 1.5rem;
}

.prose-content h3 {
    font-family: 'Nunito', sans-serif;
    font-size: 1.25rem;
    font-weight: 700;
    color: #f5f5f5;
    margin-top: 2rem;
    margin-bottom: 1rem;
}

.prose-content p {
    margin-bottom: 1rem;
}

.prose-content ul, .prose-content ol {
    margin-bottom: 1.5rem;
    padding-left: 1.5rem;
}

.prose-content li {
    margin-bottom: 0.5rem;
}

.prose-content li strong {
    color: #f5f5f5;
}

.prose-content a {
    color: #A78BFA;
    text-decoration: underline;
    text-underline-offset: 2px;
}

.prose-content a:hover {
    color: #c4b5fd;
}

/* Info Grid */
.info-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
    margin: 1.5rem 0;
}

.info-card {
    padding: 1.25rem;
    background: #141414;
    border: 1px solid #2a2a2a;
    border-radius: 12px;
}

.info-card h4 {
    font-family: 'Nunito', sans-serif;
    font-size: 1rem;
    font-weight: 700;
    color: #f5f5f5;
    margin: 0 0 0.5rem 0;
}

.info-card p {
    font-size: 0.875rem;
    color: #a3a3a3;
    margin: 0;
}

/* Comparison Grid */
.comparison-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1rem;
    margin: 1.5rem 0;
}

.comparison-card {
    padding: 1.5rem;
    background: #141414;
    border: 1px solid #2a2a2a;
    border-radius: 12px;
}

.comparison-card h4 {
    font-family: 'Nunito', sans-serif;
    font-size: 1.125rem;
    font-weight: 700;
    color: #A78BFA;
    margin: 0 0 0.75rem 0;
}

.comparison-card p {
    font-size: 0.9375rem;
    margin: 0 0 0.75rem 0;
}

.comparison-card .example {
    font-size: 0.8125rem;
    color: #6b7280;
    font-style: italic;
    margin: 0;
}

/* Callout Boxes */
.callout {
    padding: 1.25rem;
    background: rgba(167, 139, 250, 0.05);
    border-left: 3px solid #A78BFA;
    border-radius: 0 8px 8px 0;
    margin: 1.5rem 0;
}

.callout p {
    margin: 0;
    font-size: 0.9375rem;
}

.callout-link {
    background: rgba(167, 139, 250, 0.08);
}

.callout-celebration {
    background: rgba(34, 197, 94, 0.08);
    border-color: #22c55e;
}

.callout-final {
    background: rgba(167, 139, 250, 0.1);
    border-width: 4px;
    padding: 1.5rem;
}

/* Mistakes Grid */
.mistakes-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1rem;
    margin: 1.5rem 0;
}

.mistake-card {
    padding: 1.25rem;
    background: rgba(239, 68, 68, 0.05);
    border: 1px solid rgba(239, 68, 68, 0.2);
    border-radius: 12px;
}

.mistake-card h4 {
    font-family: 'Nunito', sans-serif;
    font-size: 1rem;
    font-weight: 700;
    color: #f87171;
    margin: 0 0 0.5rem 0;
}

.mistake-card p {
    font-size: 0.875rem;
    margin: 0;
}

/* Progression Grid */
.progression-grid, .tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
    margin: 1.5rem 0;
}

.progression-card, .tools-card {
    padding: 1.25rem;
    background: #141414;
    border: 1px solid #2a2a2a;
    border-radius: 12px;
}

.progression-card h4, .tools-card h4 {
    font-family: 'Nunito', sans-serif;
    font-size: 1rem;
    font-weight: 700;
    color: #A78BFA;
    margin: 0 0 1rem 0;
}

.progression-card ul, .tools-card ul {
    margin: 0;
    padding-left: 1.25rem;
}

.progression-card li, .tools-card li {
    font-size: 0.875rem;
    margin-bottom: 0.375rem;
}

/* Course Links */
.course-links {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin: 1.5rem 0;
}

.course-link-card {
    display: block;
    padding: 1.25rem;
    background: #141414;
    border: 1px solid #2a2a2a;
    border-radius: 12px;
    text-decoration: none;
    transition: all 0.2s;
}

.course-link-card:hover {
    border-color: #A78BFA;
    transform: translateX(4px);
}

.course-link-card h4 {
    font-family: 'Nunito', sans-serif;
    font-size: 1rem;
    font-weight: 700;
    color: #f5f5f5;
    margin: 0 0 0.25rem 0;
}

.course-link-card p {
    font-size: 0.875rem;
    color: #a3a3a3;
    margin: 0;
}

/* ===========================================
   INTERACTIVE CONTAINERS
   =========================================== */

.interactive-container {
    background: #141414;
    border: 1px solid #2a2a2a;
    border-radius: 16px;
    overflow: hidden;
    margin: 2rem 0;
}

.interactive-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.75rem 1.25rem;
    background: #0a0a0a;
    border-bottom: 1px solid #2a2a2a;
}

.interactive-status {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.status-dot {
    width: 8px;
    height: 8px;
    background: #A78BFA;
    border-radius: 50%;
}

.status-text {
    font-size: 0.875rem;
    font-weight: 500;
    color: #f5f5f5;
}

.interactive-label {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: #6b7280;
}

.interactive-body {
    padding: 1.5rem;
}

.interactive-tip {
    padding: 1rem 1.25rem;
    background: rgba(167, 139, 250, 0.05);
    border-top: 1px solid #2a2a2a;
    font-size: 0.875rem;
    color: #a3a3a3;
}

.tip-label {
    color: #A78BFA;
    font-weight: 600;
    margin-right: 0.5rem;
}

/* ===========================================
   SHARED CONTROLS
   =========================================== */

/* Play Button */
.play-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 3.5rem;
    height: 3.5rem;
    background: linear-gradient(135deg, #A78BFA 0%, #8b5cf6 100%);
    border: none;
    border-radius: 50%;
    color: #0a0a0a;
    cursor: pointer;
    transition: all 0.2s;
}

.play-btn:hover {
    transform: scale(1.05);
    box-shadow: 0 0 20px rgba(167, 139, 250, 0.4);
}

.play-btn svg {
    width: 24px;
    height: 24px;
}

.play-btn .stop-icon {
    display: none;
}

.play-btn.playing .play-icon {
    display: none;
}

.play-btn.playing .stop-icon {
    display: block;
}

/* Secondary Button */
.secondary-btn {
    padding: 0.5rem 1rem;
    background: transparent;
    border: 1px solid #2a2a2a;
    border-radius: 8px;
    color: #a3a3a3;
    font-size: 0.875rem;
    cursor: pointer;
    transition: all 0.2s;
}

.secondary-btn:hover {
    border-color: #A78BFA;
    color: #A78BFA;
}

/* Tempo Control */
.tempo-control {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.tempo-control label {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: #6b7280;
}

.tempo-control input[type="range"] {
    width: 100px;
    height: 6px;
    background: #2a2a2a;
    border-radius: 3px;
    -webkit-appearance: none;
    appearance: none;
}

.tempo-control input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 14px;
    height: 14px;
    background: #A78BFA;
    border-radius: 50%;
    cursor: pointer;
}

.tempo-control span {
    font-size: 0.875rem;
    font-weight: 600;
    color: #f5f5f5;
    min-width: 2.5rem;
}

/* ===========================================
   DRUM GRID BUILDER
   =========================================== */

.drum-grid-wrapper {
    display: flex;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.drum-labels {
    display: flex;
    flex-direction: column;
    gap: 4px;
    padding-top: 2px;
}

.drum-label {
    height: 36px;
    display: flex;
    align-items: center;
    font-size: 0.75rem;
    font-weight: 500;
    color: #a3a3a3;
    text-transform: uppercase;
    letter-spacing: 0.03em;
}

.drum-grid {
    display: grid;
    grid-template-columns: repeat(16, 1fr);
    grid-template-rows: repeat(4, 36px);
    gap: 4px;
    flex: 1;
}

.drum-cell {
    background: #0a0a0a;
    border: 1px solid #2a2a2a;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.1s;
}

.drum-cell:hover {
    border-color: #A78BFA;
}

.drum-cell.active {
    background: #A78BFA;
    border-color: #A78BFA;
}

.drum-cell.current {
    box-shadow: inset 0 0 0 2px rgba(255, 255, 255, 0.5);
}

/* Beat markers */
.drum-cell:nth-child(16n+1),
.drum-cell:nth-child(16n+5),
.drum-cell:nth-child(16n+9),
.drum-cell:nth-child(16n+13) {
    border-left-width: 2px;
}

.drum-controls {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.transport-controls {
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

.preset-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.preset-btn {
    padding: 0.5rem 1rem;
    background: transparent;
    border: 1px solid #2a2a2a;
    border-radius: 9999px;
    color: #a3a3a3;
    font-size: 0.8125rem;
    cursor: pointer;
    transition: all 0.2s;
}

.preset-btn:hover {
    border-color: #A78BFA;
    color: #A78BFA;
}

.preset-btn[data-preset="clear"] {
    border-color: #3a3a3a;
}

/* ===========================================
   TEMPO EXPLORER
   =========================================== */

#tempo-explorer-tool {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
}

.tempo-display {
    text-align: center;
}

.tempo-bpm {
    display: flex;
    align-items: baseline;
    justify-content: center;
    gap: 0.5rem;
}

#tempo-value {
    font-family: 'Nunito', sans-serif;
    font-size: 4rem;
    font-weight: 700;
    color: #f5f5f5;
    line-height: 1;
}

.tempo-unit {
    font-size: 1.25rem;
    color: #6b7280;
    text-transform: uppercase;
}

.tempo-genre {
    font-size: 1.125rem;
    color: #A78BFA;
    font-weight: 500;
    margin-top: 0.5rem;
}

.tempo-slider {
    width: 100%;
    max-width: 400px;
    height: 8px;
    background: #2a2a2a;
    border-radius: 4px;
    -webkit-appearance: none;
    appearance: none;
}

.tempo-slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 24px;
    height: 24px;
    background: linear-gradient(135deg, #A78BFA 0%, #8b5cf6 100%);
    border-radius: 50%;
    cursor: pointer;
    box-shadow: 0 0 10px rgba(167, 139, 250, 0.4);
}

.tempo-range-labels {
    display: flex;
    justify-content: space-between;
    width: 100%;
    max-width: 400px;
    font-size: 0.75rem;
    color: #6b7280;
}

.tempo-transport {
    margin-top: 0.5rem;
}

/* ===========================================
   PRESET EXPLORER
   =========================================== */

#preset-explorer-tool {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
}

.preset-display {
    text-align: center;
}

.current-preset {
    font-family: 'Nunito', sans-serif;
    font-size: 2rem;
    font-weight: 700;
    color: #f5f5f5;
}

.preset-description {
    font-size: 0.875rem;
    color: #6b7280;
    margin-top: 0.25rem;
}

.preset-selector {
    display: flex;
    gap: 0.5rem;
}

.preset-type-btn {
    padding: 0.75rem 1.5rem;
    background: transparent;
    border: 1px solid #2a2a2a;
    border-radius: 9999px;
    color: #a3a3a3;
    font-size: 0.9375rem;
    cursor: pointer;
    transition: all 0.2s;
}

.preset-type-btn:hover {
    border-color: #A78BFA;
    color: #A78BFA;
}

.preset-type-btn.active {
    background: #A78BFA;
    border-color: #A78BFA;
    color: #0a0a0a;
}

.preset-transport {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.75rem;
}

.transport-label {
    font-size: 0.75rem;
    color: #6b7280;
}

/* ===========================================
   CHORD PROGRESSION PLAYER
   =========================================== */

.chord-slots {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.chord-slot {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.chord-slot label {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: #6b7280;
}

.chord-select {
    padding: 0.75rem 1rem;
    background: #0a0a0a;
    border: 1px solid #2a2a2a;
    border-radius: 8px;
    color: #f5f5f5;
    font-size: 0.9375rem;
    cursor: pointer;
    transition: border-color 0.2s;
}

.chord-select:hover, .chord-select:focus {
    border-color: #A78BFA;
    outline: none;
}

.chord-slot.playing .chord-select {
    border-color: #A78BFA;
    box-shadow: 0 0 10px rgba(167, 139, 250, 0.3);
}

.chord-keyboard {
    height: 80px;
    background: #0a0a0a;
    border: 1px solid #2a2a2a;
    border-radius: 8px;
    margin-bottom: 1.5rem;
    display: flex;
    align-items: flex-end;
    padding: 0.5rem;
    position: relative;
    overflow: hidden;
}

.piano-key {
    flex: 1;
    height: 100%;
    background: #f5f5f5;
    border-radius: 0 0 4px 4px;
    margin: 0 1px;
    transition: all 0.1s;
}

.piano-key.black {
    position: absolute;
    width: 6%;
    height: 60%;
    background: #1a1a1a;
    z-index: 1;
    margin: 0;
    border-radius: 0 0 3px 3px;
}

.piano-key.active {
    background: #A78BFA;
}

.piano-key.black.active {
    background: #8b5cf6;
}

.chord-presets {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
}

.chord-preset-btn {
    padding: 0.5rem 1rem;
    background: transparent;
    border: 1px solid #2a2a2a;
    border-radius: 9999px;
    color: #a3a3a3;
    font-size: 0.8125rem;
    cursor: pointer;
    transition: all 0.2s;
}

.chord-preset-btn:hover {
    border-color: #A78BFA;
    color: #A78BFA;
}

.chord-transport {
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

/* ===========================================
   BASS PATTERN BUILDER
   =========================================== */

.bass-chord-display {
    text-align: center;
    margin-bottom: 1.5rem;
}

.current-chord-label {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: #6b7280;
}

.current-chords {
    display: block;
    font-family: 'Nunito', sans-serif;
    font-size: 1.5rem;
    font-weight: 700;
    color: #f5f5f5;
    margin-top: 0.25rem;
}

.bass-pattern-options, .bass-sound-options {
    margin-bottom: 1.5rem;
}

.bass-pattern-options label, .bass-sound-options label {
    display: block;
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: #6b7280;
    margin-bottom: 0.75rem;
}

.bass-pattern-buttons, .bass-sound-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.bass-pattern-btn, .bass-sound-btn {
    padding: 0.5rem 1rem;
    background: transparent;
    border: 1px solid #2a2a2a;
    border-radius: 9999px;
    color: #a3a3a3;
    font-size: 0.8125rem;
    cursor: pointer;
    transition: all 0.2s;
}

.bass-pattern-btn:hover, .bass-sound-btn:hover {
    border-color: #A78BFA;
    color: #A78BFA;
}

.bass-pattern-btn.active, .bass-sound-btn.active {
    background: #A78BFA;
    border-color: #A78BFA;
    color: #0a0a0a;
}

.bass-transport {
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

.bass-toggle {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.875rem;
    color: #a3a3a3;
    cursor: pointer;
}

.bass-toggle input[type="checkbox"] {
    width: 16px;
    height: 16px;
    accent-color: #A78BFA;
}

/* ===========================================
   MELODY SKETCH PAD
   =========================================== */

.melody-display {
    min-height: 60px;
    background: #0a0a0a;
    border: 1px solid #2a2a2a;
    border-radius: 8px;
    padding: 1rem;
    margin-bottom: 1rem;
}

.melody-notes {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.melody-placeholder {
    color: #6b7280;
    font-size: 0.875rem;
}

.melody-note {
    padding: 0.25rem 0.75rem;
    background: #A78BFA;
    border-radius: 4px;
    color: #0a0a0a;
    font-size: 0.875rem;
    font-weight: 500;
}

.melody-keyboard {
    display: flex;
    height: 100px;
    margin-bottom: 1rem;
    position: relative;
}

.melody-key {
    flex: 1;
    background: #f5f5f5;
    border: 1px solid #d4d4d4;
    border-radius: 0 0 6px 6px;
    cursor: pointer;
    transition: all 0.1s;
    display: flex;
    align-items: flex-end;
    justify-content: center;
    padding-bottom: 0.5rem;
    font-size: 0.75rem;
    color: #525252;
}

.melody-key:hover {
    background: #e5e5e5;
}

.melody-key:active, .melody-key.active {
    background: #A78BFA;
    border-color: #A78BFA;
    color: #0a0a0a;
}

.melody-options {
    margin-bottom: 1rem;
}

.note-length-selector {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.note-length-selector label {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: #6b7280;
}

.note-length-btn {
    padding: 0.375rem 0.75rem;
    background: transparent;
    border: 1px solid #2a2a2a;
    border-radius: 6px;
    color: #a3a3a3;
    font-size: 0.8125rem;
    cursor: pointer;
    transition: all 0.2s;
}

.note-length-btn:hover {
    border-color: #A78BFA;
    color: #A78BFA;
}

.note-length-btn.active {
    background: #A78BFA;
    border-color: #A78BFA;
    color: #0a0a0a;
}

.melody-transport {
    display: flex;
    align-items: center;
    gap: 1rem;
}

/* ===========================================
   ARRANGEMENT BUILDER
   =========================================== */

.arrangement-palette {
    margin-bottom: 1.5rem;
}

.palette-label {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: #6b7280;
    margin-bottom: 0.75rem;
}

.arrangement-blocks {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.arrangement-block {
    padding: 0.75rem 1.25rem;
    background: #A78BFA;
    border-radius: 8px;
    color: #0a0a0a;
    font-size: 0.875rem;
    font-weight: 600;
    cursor: grab;
    transition: all 0.2s;
}

.arrangement-block:active {
    cursor: grabbing;
}

.arrangement-block[data-type="intro"] {
    background: #60a5fa;
}

.arrangement-block[data-type="build"] {
    background: #fbbf24;
}

.arrangement-block[data-type="drop"] {
    background: #A78BFA;
}

.arrangement-block[data-type="break"] {
    background: #4ade80;
}

.arrangement-block[data-type="outro"] {
    background: #f472b6;
}

.arrangement-timeline {
    display: grid;
    grid-template-columns: repeat(8, 1fr);
    gap: 0.5rem;
    margin-bottom: 1.5rem;
}

.timeline-slot {
    height: 80px;
    background: #0a0a0a;
    border: 2px dashed #2a2a2a;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s;
}

.timeline-slot.drag-over {
    border-color: #A78BFA;
    background: rgba(167, 139, 250, 0.1);
}

.timeline-slot.current {
    box-shadow: inset 0 0 0 2px #A78BFA;
}

.timeline-slot .slot-block {
    padding: 0.5rem 0.75rem;
    border-radius: 6px;
    color: #0a0a0a;
    font-size: 0.75rem;
    font-weight: 600;
}

.arrangement-presets {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
}

.arrangement-preset-btn {
    padding: 0.5rem 1rem;
    background: transparent;
    border: 1px solid #2a2a2a;
    border-radius: 9999px;
    color: #a3a3a3;
    font-size: 0.8125rem;
    cursor: pointer;
    transition: all 0.2s;
}

.arrangement-preset-btn:hover {
    border-color: #A78BFA;
    color: #A78BFA;
}

.arrangement-transport {
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

.arrangement-progress {
    flex: 1;
    height: 8px;
    background: #2a2a2a;
    border-radius: 4px;
    overflow: hidden;
}

.arrangement-progress .progress-bar {
    height: 100%;
    background: #A78BFA;
    width: 0%;
    transition: width 0.1s linear;
}

/* ===========================================
   FILTER SWEEP CONTROLLER
   =========================================== */

#filter-sweep-tool {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
}

.filter-display {
    text-align: center;
}

#filter-freq {
    font-family: 'Nunito', sans-serif;
    font-size: 3rem;
    font-weight: 700;
    color: #f5f5f5;
    line-height: 1;
}

.filter-unit {
    font-size: 1rem;
    color: #6b7280;
}

.filter-slider-container {
    display: flex;
    align-items: center;
    gap: 1rem;
    height: 200px;
}

.filter-slider {
    width: 8px;
    height: 180px;
    background: #2a2a2a;
    border-radius: 4px;
    -webkit-appearance: slider-vertical;
    appearance: slider-vertical;
    writing-mode: bt-lr;
}

.filter-slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 24px;
    height: 24px;
    background: linear-gradient(135deg, #A78BFA 0%, #8b5cf6 100%);
    border-radius: 50%;
    cursor: pointer;
}

.filter-labels {
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    height: 100%;
    font-size: 0.75rem;
    color: #6b7280;
}

.filter-presets {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.filter-preset-btn {
    padding: 0.5rem 1rem;
    background: transparent;
    border: 1px solid #2a2a2a;
    border-radius: 9999px;
    color: #a3a3a3;
    font-size: 0.8125rem;
    cursor: pointer;
    transition: all 0.2s;
}

.filter-preset-btn:hover {
    border-color: #A78BFA;
    color: #A78BFA;
}

.filter-transport {
    margin-top: 0.5rem;
}

/* ===========================================
   PANNING VISUALIZER
   =========================================== */

.panning-field {
    margin-bottom: 1.5rem;
}

.panning-labels {
    display: flex;
    justify-content: space-between;
    font-size: 0.75rem;
    color: #6b7280;
    margin-bottom: 0.5rem;
}

.panning-track {
    position: relative;
    height: 120px;
    background: #0a0a0a;
    border: 1px solid #2a2a2a;
    border-radius: 8px;
}

.panning-element {
    position: absolute;
    top: 50%;
    transform: translate(-50%, -50%);
    padding: 0.5rem 0.75rem;
    background: #A78BFA;
    border-radius: 6px;
    color: #0a0a0a;
    font-size: 0.75rem;
    font-weight: 600;
    cursor: grab;
    transition: background 0.2s;
    user-select: none;
}

.panning-element:active {
    cursor: grabbing;
}

.panning-element[data-element="kick"],
.panning-element[data-element="snare"],
.panning-element[data-element="bass"] {
    background: #60a5fa;
}

.panning-element[data-element="chords"] {
    background: #fbbf24;
}

.panning-element[data-element="lead"] {
    background: #f472b6;
}

.panning-element[data-element="hats"] {
    background: #4ade80;
}

.panning-presets {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
}

.panning-preset-btn {
    padding: 0.5rem 1rem;
    background: transparent;
    border: 1px solid #2a2a2a;
    border-radius: 9999px;
    color: #a3a3a3;
    font-size: 0.8125rem;
    cursor: pointer;
    transition: all 0.2s;
}

.panning-preset-btn:hover {
    border-color: #A78BFA;
    color: #A78BFA;
}

.panning-transport {
    display: flex;
    justify-content: center;
}

/* ===========================================
   LOUDNESS COMPARISON
   =========================================== */

#loudness-tool {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
}

.loudness-options {
    display: flex;
    gap: 1rem;
}

.loudness-btn {
    padding: 1rem 1.5rem;
    background: #0a0a0a;
    border: 1px solid #2a2a2a;
    border-radius: 12px;
    cursor: pointer;
    transition: all 0.2s;
    text-align: center;
}

.loudness-btn:hover {
    border-color: #A78BFA;
}

.loudness-btn.active {
    border-color: #A78BFA;
    background: rgba(167, 139, 250, 0.1);
}

.loudness-label {
    display: block;
    font-size: 1rem;
    font-weight: 600;
    color: #f5f5f5;
    margin-bottom: 0.25rem;
}

.loudness-desc {
    display: block;
    font-size: 0.75rem;
    color: #6b7280;
}

.loudness-meter {
    width: 100%;
    max-width: 300px;
    height: 24px;
    background: #0a0a0a;
    border: 1px solid #2a2a2a;
    border-radius: 4px;
    overflow: hidden;
}

.loudness-meter .meter-bar {
    height: 100%;
    background: linear-gradient(90deg, #4ade80, #fbbf24, #f87171);
    width: 50%;
    transition: width 0.1s;
}

.loudness-transport {
    margin-top: 0.5rem;
}

/* ===========================================
   COURSE NAVIGATION
   =========================================== */

.course-nav {
    display: flex;
    justify-content: space-between;
    gap: 1rem;
    margin-top: 3rem;
    padding-top: 2rem;
    border-top: 1px solid #2a2a2a;
}

.course-nav .btn-secondary, .course-nav .btn-primary {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

/* ===========================================
   RESPONSIVE
   =========================================== */

@media (max-width: 768px) {
    .lesson-title {
        font-size: 1.5rem;
    }

    .drum-labels {
        display: none;
    }

    .drum-grid {
        grid-template-columns: repeat(16, 1fr);
    }

    .drum-cell {
        min-height: 28px;
    }

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

    .tempo-display #tempo-value {
        font-size: 3rem;
    }

    .arrangement-timeline {
        grid-template-columns: repeat(4, 1fr);
    }

    .loudness-options {
        flex-direction: column;
    }

    .course-nav {
        flex-direction: column;
    }
}