/* Components: buttons, cards, media, track, key, and chord controls
   Generated from the original stylesheet and kept in cascade order. */

/* ====================
   首頁引導按鈕
   ==================== */
.hero-tagline {
    color: #b8b8b8;
    font-size: 18px;
    margin-top: 0;
    margin-bottom: 22px;
}

/* 新增：品牌專屬標語的藝術字體設計 */
.signature-slogan {
    font-family: 'Noto Serif TC', serif; /* 使用襯線體增加文學與藝術感 */
    font-style: italic; /* 斜體設計 */
    font-size: 22px; /* 字體稍微放大 */
    color: #e5d3b3; /* 使用你最亮眼的品牌金色 */
    letter-spacing: 1.5px; /* 字距拉開，增加呼吸感 */
    margin-top: 5px;
    margin-bottom: 30px;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin-bottom: 28px;
}

.primary-button,
.secondary-button {
    display: inline-block;
    text-decoration: none;
    font-weight: bold;
    border-radius: 999px;
    padding: 11px 18px;
    transition: transform 0.3s ease, background-color 0.3s ease, border-color 0.3s ease;
}

.primary-button {
    color: #121212;
    background-color: #c4a484;
    border: 1px solid #c4a484;
}

.primary-button:hover {
    background-color: #e5d3b3;
    border-color: #e5d3b3;
    transform: translateY(-2px);
}

.primary-button:active {
    transform: translateY(0) scale(0.96); /* 按下時微縮 */
    background-color: #b39578; /* 顏色稍微變深 */
    border-color: #b39578;
}

.secondary-button {
    color: #c4a484;
    background-color: transparent;
    border: 1px solid #c4a484;
}

.secondary-button:hover {
    color: #121212;
    background-color: #c4a484;
    transform: translateY(-2px);
}

.secondary-button:active {
    transform: translateY(0) scale(0.96);
    background-color: #b39578;
    color: #121212;
}

.track-card-list {
    display: grid;
    gap: 15px;
}

.tracks-page {
    max-width: 1180px;
    margin: 60px auto;
    padding: 0 40px;
    /* 讓整個伴奏頁面載入時，套用專屬的絲滑高級感淡入動畫 */
    animation: fadeInPremium 0.8s cubic-bezier(0.2, 0.8, 0.2, 1) forwards;
}

.all-tracks-grid {
    display: grid;
    gap: 16px;
    margin-top: 32px;
}

.key-selector {
    margin-top: 34px;
}

.key-finder-panel {
    background-color: #1f1f1f;
    border: 1px solid #333;
    border-left: 5px solid #c4a484;
    border-radius: 8px;
    padding: 20px;
    margin-top: 34px;
    animation: fadeInPremium 0.7s cubic-bezier(0.2, 0.8, 0.2, 1) forwards;
}

.key-finder-copy {
    color: #b8b8b8;
    margin: 0;
    line-height: 1.7;
}

.key-finder-upload {
    position: relative;
    display: grid;
    grid-template-columns: minmax(0, 1fr) 116px;
    gap: 12px;
    align-items: stretch;
    margin-top: 18px;
}

.key-finder-upload input[type="file"] {
    position: absolute;
    width: 1px;
    height: 1px;
    opacity: 0;
    pointer-events: none;
}

.upload-file-label {
    display: grid;
    gap: 4px;
    min-width: 0;
    padding: 16px 18px;
    background:
        linear-gradient(90deg, rgba(127, 183, 173, 0.08), transparent 38%),
        rgba(42, 42, 42, 0.96);
    border: 1px solid rgba(127, 183, 173, 0.28);
    border-radius: 12px;
    color: #e0e0e0;
    cursor: pointer;
    transition: border-color 0.25s ease, box-shadow 0.25s ease, background-color 0.25s ease;
}

.upload-file-label:hover,
.key-finder-upload input[type="file"]:focus + .upload-file-label {
    border-color: var(--teal);
    box-shadow: 0 0 0 3px rgba(127, 183, 173, 0.12);
}

.upload-file-label span {
    color: var(--teal);
    font-size: 12px;
    font-weight: bold;
    text-transform: uppercase;
}

.upload-file-label strong {
    overflow: hidden;
    color: var(--gold-light);
    font-size: 16px;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.upload-file-label small {
    color: var(--muted);
    font-size: 12px;
    line-height: 1.5;
}

.analyze-file-button {
    display: inline-grid;
    place-items: center;
    min-width: 0;
    min-height: 74px;
    padding: 12px 14px;
    border-radius: 14px;
    font-size: 14px;
    white-space: nowrap;
    box-shadow: 0 10px 26px rgba(0, 0, 0, 0.18);
}

.analyze-file-button:hover {
    box-shadow: 0 14px 30px rgba(0, 0, 0, 0.24);
}

.analyze-file-button:disabled {
    opacity: 0.62;
    cursor: wait;
    transform: none;
    box-shadow: none;
}

.key-finder-divider {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-top: 18px;
    color: var(--muted);
    font-size: 12px;
    font-weight: bold;
    text-transform: uppercase;
}

.key-finder-divider::before,
.key-finder-divider::after {
    content: "";
    flex: 1;
    height: 1px;
    background: rgba(196, 164, 132, 0.16);
}

.key-finder-form {
    display: flex;
    gap: 12px;
    margin-top: 16px;
}

.key-finder-form input {
    flex: 1;
    min-width: 0;
    padding: 11px 14px;
    background-color: #2a2a2a;
    border: 1px solid #444;
    color: #fff;
    border-radius: 999px;
    box-sizing: border-box;
    font-family: inherit;
}

.key-finder-form input:focus {
    outline: 3px solid rgba(229, 211, 179, 0.4);
    border-color: #c4a484;
}

.key-finder-form button:disabled {
    opacity: 0.6;
    cursor: wait;
    transform: none;
}

.api-status {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: var(--muted);
    font-size: 13px;
    font-weight: bold;
    padding: 7px 10px;
    background: rgba(18, 18, 18, 0.48);
    border: 1px solid rgba(196, 164, 132, 0.14);
    border-radius: 999px;
}

.key-finder-status-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 16px;
}

.helper-status {
    margin-right: auto;
}

.helper-start-button {
    min-height: 32px;
    padding: 6px 10px;
    color: var(--teal);
    border: 1px solid rgba(127, 183, 173, 0.22);
    border-radius: 999px;
}

.helper-start-button:hover,
.helper-start-button:focus-visible {
    color: var(--text);
    background: rgba(127, 183, 173, 0.12);
}

.helper-start-button[hidden] {
    display: none;
}

.helper-install-card {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    gap: 18px;
    margin: -2px 0 16px;
    padding: 14px 16px;
    background: linear-gradient(135deg, rgba(127, 183, 173, 0.1), rgba(196, 164, 132, 0.08));
    border: 1px solid rgba(127, 183, 173, 0.24);
    border-radius: 8px;
}

.helper-install-copy strong {
    display: block;
    margin-bottom: 4px;
    color: var(--text);
    font-size: 15px;
}

.helper-install-copy p {
    margin: 0 0 9px;
    color: var(--muted);
    font-size: 13px;
    line-height: 1.55;
}

.helper-install-copy ol {
    display: grid;
    gap: 4px;
    margin: 0;
    padding-left: 20px;
    color: var(--text-soft);
    font-size: 13px;
    line-height: 1.45;
}

.helper-download-actions {
    flex: 0 0 auto;
    justify-self: center;
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    justify-content: center;
}

.helper-download-link {
    flex: 0 0 auto;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 38px;
    padding: 8px 14px;
    font-size: 13px;
    line-height: 1.2;
    text-align: center;
    white-space: nowrap;
}

@media (max-width: 720px) {
    .helper-install-card {
        grid-template-columns: 1fr;
        justify-items: stretch;
    }

    .helper-download-link {
        justify-self: stretch;
        text-align: center;
    }

    .helper-download-actions {
        justify-self: stretch;
    }

    .helper-download-link {
        flex: 1 1 160px;
    }
}

.segmented-control {
    display: inline-grid;
    grid-template-columns: repeat(2, minmax(74px, 1fr));
    padding: 3px;
    background: rgba(12, 12, 12, 0.72);
    border: 1px solid rgba(196, 164, 132, 0.18);
    border-radius: 8px;
}

.result-mode-button {
    min-height: 34px;
    padding: 6px 12px;
    color: var(--muted);
    background: transparent;
    border: 0;
    border-radius: 6px;
    font: inherit;
    font-size: 13px;
    font-weight: bold;
    cursor: pointer;
}

.result-mode-button.active {
    color: #111;
    background: var(--gold-light);
}

.service-wake-panel {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-top: 14px;
    padding: 12px 14px;
    color: var(--text);
    background: rgba(127, 183, 173, 0.08);
    border: 1px solid rgba(127, 183, 173, 0.24);
    border-radius: var(--radius);
}

.service-wake-panel[hidden] {
    display: none;
}

.service-wake-panel p {
    margin: 3px 0 0;
    color: var(--muted);
    font-size: 13px;
}

.service-wake-panel.is-offline {
    background: rgba(167, 111, 115, 0.08);
    border-color: rgba(167, 111, 115, 0.32);
}

.service-wake-link {
    display: inline-block;
    margin-top: 7px;
    color: var(--teal);
    font-size: 13px;
    font-weight: bold;
}

.wake-spinner,
.analysis-spinner {
    width: 20px;
    height: 20px;
    flex: 0 0 auto;
    border: 2px solid rgba(127, 183, 173, 0.24);
    border-top-color: var(--teal);
    border-radius: 50%;
    animation: keyFinderSpin 0.8s linear infinite;
}

.upload-privacy-note {
    margin: 9px 0 0;
    color: var(--muted);
    font-size: 12px;
    line-height: 1.5;
}

.analysis-progress {
    display: grid;
    gap: 14px;
}

.analysis-progress-heading {
    display: flex;
    align-items: center;
    gap: 12px;
}

.analysis-progress-heading div {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
    gap: 12px;
}

.analysis-progress-heading span {
    color: var(--gold-light);
    font-weight: bold;
}

.analysis-progress-bar {
    height: 7px;
    overflow: hidden;
    background: rgba(255, 255, 255, 0.08);
    border-radius: 999px;
}

.analysis-progress-bar span {
    display: block;
    height: 100%;
    background: linear-gradient(90deg, var(--teal), var(--gold-light));
    border-radius: inherit;
    transition: width 0.35s ease;
}

.analysis-skeleton {
    display: grid;
    gap: 9px;
}

.analysis-skeleton span {
    height: 12px;
    background: linear-gradient(
        90deg,
        rgba(255, 255, 255, 0.05) 25%,
        rgba(255, 255, 255, 0.11) 50%,
        rgba(255, 255, 255, 0.05) 75%
    );
    background-size: 200% 100%;
    border-radius: 5px;
    animation: skeletonSweep 1.3s ease-in-out infinite;
}

.analysis-skeleton span:nth-child(2) {
    width: 82%;
}

.analysis-skeleton span:nth-child(3) {
    width: 62%;
}

.result-title-row {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 10px;
}

.certainty-badge {
    padding: 4px 8px;
    font-size: 11px;
    font-weight: bold;
    text-transform: uppercase;
    border: 1px solid currentColor;
    border-radius: 999px;
}

.certainty-high {
    color: #92cbb3;
}

.certainty-medium {
    color: #dfc48f;
}

.certainty-low {
    color: #df9ea3;
}

.confidence-note {
    margin: 10px 0 0;
    padding: 10px 12px;
    color: var(--muted);
    background: rgba(127, 183, 173, 0.06);
    border-left: 3px solid rgba(127, 183, 173, 0.48);
    border-radius: 0 6px 6px 0;
    font-size: 13px;
    line-height: 1.55;
}

.confidence-note.is-uncertain {
    color: #e2c1c4;
    background: rgba(167, 111, 115, 0.08);
    border-left-color: #a76f73;
}

.result-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 14px;
}

.result-actions .primary-button,
.result-actions .secondary-button {
    padding: 9px 13px;
    border-radius: 7px;
    font-size: 13px;
}

.result-mode-quick .result-detail-section {
    display: none;
}

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

@keyframes skeletonSweep {
    from {
        background-position: 180% 0;
    }
    to {
        background-position: -20% 0;
    }
}

.status-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--gold);
    box-shadow: 0 0 0 3px rgba(196, 164, 132, 0.12);
}

.api-status.is-online .status-dot {
    background: var(--teal);
    box-shadow: 0 0 0 3px rgba(127, 183, 173, 0.16);
}

.api-status.is-offline .status-dot {
    background: var(--wine);
    box-shadow: 0 0 0 3px rgba(167, 111, 115, 0.18);
}

.analysis-history {
    margin-top: 18px;
    padding: 16px;
    background: rgba(18, 18, 18, 0.42);
    border: 1px solid rgba(196, 164, 132, 0.14);
    border-radius: var(--radius);
}

.history-heading {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 12px;
    margin-bottom: 10px;
}

.history-heading h3 {
    color: var(--gold-light);
    font-size: 16px;
    margin: 0;
}

.text-button {
    color: var(--teal);
    background: transparent;
    border: none;
    padding: 4px 0;
    font-family: inherit;
    font-weight: bold;
    cursor: pointer;
}

.analysis-history ul {
    display: grid;
    gap: 9px;
    list-style: none;
    margin: 0;
    padding: 0;
}

.analysis-history li {
    display: grid;
    gap: 5px;
    padding: 0;
    border-top: 1px solid rgba(255, 255, 255, 0.07);
}

.analysis-history li:first-child {
    border-top: none;
}

.history-item-button {
    display: grid;
    gap: 5px;
    width: 100%;
    padding: 10px 0;
    color: inherit;
    background: transparent;
    border: 0;
    text-align: left;
    cursor: pointer;
}

.history-item-button:hover strong,
.history-item-button:focus-visible strong {
    color: var(--teal);
}

.history-item-button:focus-visible {
    outline: 2px solid rgba(127, 183, 173, 0.65);
    outline-offset: 4px;
    border-radius: 6px;
}

.history-item-button:disabled {
    cursor: default;
    opacity: 0.72;
}

.analysis-history li div {
    display: flex;
    justify-content: space-between;
    gap: 14px;
}

.analysis-history strong {
    color: var(--gold-light);
}

.analysis-history span,
.analysis-history a,
.analysis-history em {
    color: var(--muted);
    font-size: 13px;
}

.analysis-history em {
    color: rgba(127, 183, 173, 0.82);
    font-style: normal;
}

.history-item-button:disabled em {
    color: rgba(224, 183, 186, 0.72);
}

.analysis-history a {
    overflow-wrap: anywhere;
    text-decoration: none;
}

.analysis-history a:hover {
    color: var(--teal);
}

.key-finder-result {
    margin-top: 18px;
    color: #e0e0e0;
    line-height: 1.7;
}

.key-finder-final {
    color: #e5d3b3;
    font-family: 'Noto Serif TC', serif;
    font-size: 30px;
    font-weight: bold;
    margin-bottom: 4px;
}

.key-finder-confidence,
.key-finder-meta,
.key-finder-notes {
    margin: 6px 0;
}

.key-finder-candidates {
    margin-top: 14px;
}

.key-finder-candidates p {
    color: var(--gold);
    font-size: 15px;
    margin: 0 0 8px;
}

.key-finder-candidates p span {
    color: #aaa;
    font-size: 13px;
}

.key-finder-candidates ul {
    display: grid;
    gap: 8px;
    list-style: none;
    margin: 0;
    padding: 0;
}

.key-finder-candidates li {
    display: flex;
    justify-content: space-between;
    gap: 12px;
    background-color: #2a2a2a;
    border: 1px solid #3a3a3a;
    border-radius: 8px;
    padding: 9px 12px;
}

.key-finder-candidates li span {
    color: #c4a484;
    flex-shrink: 0;
}

.key-button-grid {
    display: grid;
    grid-template-columns: repeat(6, 1fr);
    gap: 12px;
    margin-top: 16px;
}

.key-button {
    color: #121212;
    background-color: #c4a484;
    border: 1px solid #c4a484;
    border-radius: 999px;
    padding: 10px 14px;
    font-family: inherit;
    font-weight: bold;
    cursor: pointer;
    transition: background-color 0.3s ease, transform 0.3s ease;
}

.key-button:hover {
    background-color: #e5d3b3;
    transform: translateY(-2px);
}

.select-key-button {
    color: #121212;
    background-color: #c4a484;
    border: 1px solid #c4a484;
    border-radius: 999px;
    padding: 11px 18px;
    font-family: inherit;
    font-weight: bold;
    cursor: pointer;
    margin-bottom: 24px;
    transition: background-color 0.3s ease, transform 0.3s ease;
}

.select-key-button:hover {
    background-color: #e5d3b3;
    transform: translateY(-2px);
}

.key-result {
    background-color: #1f1f1f;
    border: 1px solid #333;
    border-left: 5px solid #c4a484;
    border-radius: 10px;
    padding: 20px;
    margin-top: 34px;
    /* 預設先讓區塊顯示淡入動畫 */
    animation: fadeInPremium 0.7s cubic-bezier(0.2, 0.8, 0.2, 1) forwards;
}

/* 新增：專屬的絲滑高級感淡入動畫 */
@keyframes fadeInPremium {
    0% {
        opacity: 0;
        transform: translateY(15px) scale(0.98); /* 加上微小的縮放感 */
    }
    100% {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

.key-result h3 {
    color: #c4a484;
    margin: 0 0 10px;
    font-size: 22px;
}

.key-result p {
    color: #e0e0e0;
    margin: 0;
    font-size: 18px;
    line-height: 1.7;
}

.note-grid {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    gap: 10px;
    margin-top: 16px;
}

.note-card {
    background-color: #2a2a2a;
    border: 1px solid #3a3a3a;
    border-radius: 10px;
    padding: 14px 10px;
    text-align: center;
}

.progression-section {
    margin-top: 28px;
}

.progression-section h4 {
    color: #c4a484;
    margin: 0 0 16px;
    font-size: 20px;
}

.progression-category {
    display: grid;
    gap: 12px;
    margin-top: 18px;
    padding: 0;
    border: 1px solid color-mix(in srgb, var(--border-soft, #333) 86%, transparent);
    border-radius: 8px;
    background: color-mix(in srgb, var(--subpanel-background, #202020) 72%, transparent);
    overflow: hidden;
}

.progression-category:first-of-type {
    margin-top: 0;
}

.progression-category-heading {
    position: relative;
    display: flex;
    justify-content: space-between;
    align-items: end;
    gap: 16px;
    padding: 13px 48px 13px 14px;
    border-bottom: 1px solid color-mix(in srgb, var(--border-soft, #333) 82%, transparent);
    cursor: pointer;
    list-style: none;
    user-select: none;
}

.progression-category-heading::-webkit-details-marker {
    display: none;
}

.progression-category-heading::after {
    content: "+";
    position: absolute;
    top: 50%;
    right: 16px;
    color: var(--chord-control, var(--teal));
    font-size: 22px;
    font-weight: 800;
    line-height: 1;
    transform: translateY(-50%);
}

.progression-category[open] .progression-category-heading::after {
    content: "\2212";
}

.progression-category-heading:hover {
    background: var(--control-hover-background);
}

.progression-category-heading:focus-visible {
    outline: 3px solid var(--focus-ring);
    outline-offset: -3px;
}

.progression-category-title {
    margin: 0;
    color: var(--gold-light);
    font-size: 16px;
    font-weight: 800;
    line-height: 1.2;
}

.progression-category-meta {
    display: grid;
    justify-items: end;
    gap: 4px;
    max-width: 620px;
}

.progression-category-meta span {
    color: var(--text-subtle, #aaa);
    font-size: 13px;
    line-height: 1.45;
    text-align: right;
}

.progression-category-meta strong {
    color: var(--teal);
    font-size: 12px;
    letter-spacing: .04em;
    text-transform: uppercase;
}

.progression-grid {
    display: grid;
    gap: 12px;
    padding: 12px;
}

.progression-card {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: flex-start;
    gap: 14px;
    background-color: #2a2a2a;
    border: 1px solid #3a3a3a;
    border-radius: 10px;
    padding: 14px 16px;
}

.progression-card-actions {
    display: flex;
    flex-wrap: nowrap;
    justify-content: flex-end;
    align-items: center;
    gap: 7px;
    white-space: nowrap;
}

.progression-save-button,
.progression-export-button {
    min-height: 34px;
    padding: 7px 10px;
    color: var(--gold-light);
    background: transparent;
    border: 1px solid rgba(196, 164, 132, 0.34);
    border-radius: 6px;
    font: inherit;
    font-size: 12px;
    font-weight: bold;
    cursor: pointer;
}

.progression-save-button:hover,
.progression-export-button:hover {
    color: #111;
    background: var(--gold-light);
}

.progression-chords {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 7px;
}

.progression-chord-token {
    padding: 2px 5px;
    border-radius: 4px;
    color: inherit;
    text-decoration: none;
    transition: color 0.18s ease, background-color 0.18s ease;
}

.progression-chord-token:hover {
    color: var(--teal);
    box-shadow: inset 0 -1px 0 currentColor;
}

.progression-chord-token:focus-visible {
    outline: 3px solid var(--focus-ring);
    outline-offset: 2px;
}

.progression-chord-token.is-current {
    color: #111;
    background: var(--gold-light);
    box-shadow: none;
}

.progression-chord-token.is-next {
    color: var(--teal);
    box-shadow: inset 0 0 0 1px rgba(127, 183, 173, 0.42);
}

.progression-separator {
    color: var(--muted);
}

.selected-key-heading {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
}

.selected-key-heading h3 {
    margin: 3px 0 0;
}

.transpose-controls {
    display: flex;
    gap: 7px;
}

.transpose-controls button {
    width: 42px;
    height: 36px;
    color: var(--gold-light);
    background: rgba(18, 18, 18, 0.62);
    border: 1px solid rgba(196, 164, 132, 0.32);
    border-radius: 6px;
    font: inherit;
    font-weight: bold;
    cursor: pointer;
}

.transpose-controls button:hover {
    color: #111;
    background: var(--gold-light);
}

.progression-controls select {
    min-height: 34px;
    padding: 6px 8px;
    color: var(--text);
    background: #242424;
    border: 1px solid rgba(196, 164, 132, 0.26);
    border-radius: 6px;
}

.progression-controls-expanded {
    align-items: end;
}

.key-button.is-selected {
    color: #111;
    background: var(--teal);
    border-color: var(--teal);
}

.saved-progression-section {
    margin-top: 24px;
    padding-top: 18px;
    border-top: 1px solid rgba(196, 164, 132, 0.14);
}

.saved-progression-section h4 {
    margin: 0 0 12px;
    color: var(--gold-light);
}

#savedProgressions {
    display: grid;
    gap: 8px;
}

.saved-progression-item {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 14px;
    padding: 11px 12px;
    background: rgba(18, 18, 18, 0.45);
    border: 1px solid rgba(127, 183, 173, 0.15);
    border-radius: 7px;
}

.saved-progression-item div {
    display: grid;
    gap: 3px;
}

.saved-progression-item strong {
    color: var(--gold-light);
}

.saved-progression-item span,
.saved-progression-empty {
    color: var(--muted);
    font-size: 13px;
}

.saved-progression-delete {
    color: #d9a8ac;
    background: transparent;
    border: 0;
    font: inherit;
    font-size: 12px;
    font-weight: bold;
    cursor: pointer;
}

.progression-card.is-playing {
    border-color: rgba(127, 183, 173, 0.72);
    box-shadow: 0 0 0 1px rgba(127, 183, 173, 0.18);
}

.progression-main {
    min-width: 0;
}

.progression-numerals,
.progression-chords,
.progression-style {
    display: block;
}

.progression-numerals {
    color: #c4a484;
    font-weight: bold;
    margin-bottom: 6px;
}

.progression-chords {
    color: #e0e0e0;
    font-size: 18px;
    font-weight: bold;
    margin-bottom: 6px;
}

.progression-style {
    color: #aaa;
    font-size: 14px;
}

.progression-description {
    margin: 2px 0 0;
    color: var(--text-subtle, #aaa);
    font-size: 13px;
    line-height: 1.5;
}

.progression-scale-advice {
    display: grid;
    gap: 12px;
    margin-top: 14px;
    padding: 14px;
    border: 1px solid color-mix(in srgb, var(--border-strong, #3a3a3a) 76%, transparent);
    border-radius: 10px;
    background: color-mix(in srgb, var(--card-soft, #222) 72%, transparent);
}

.scale-advice-summary {
    display: flex;
    flex-wrap: wrap;
    align-items: baseline;
    gap: 8px 12px;
}

.scale-advice-kicker,
.scale-advice-grid span,
.scale-advice-detail summary {
    color: var(--text-subtle, #aaa);
    font-size: 12px;
    font-weight: 800;
    letter-spacing: .04em;
    text-transform: uppercase;
}

.scale-advice-summary strong {
    color: var(--text-strong, #e0e0e0);
    font-size: 15px;
}

.scale-advice-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 10px;
}

.scale-advice-grid div {
    min-width: 0;
    padding: 10px 12px;
    border: 1px solid color-mix(in srgb, var(--border-soft, #333) 82%, transparent);
    border-radius: 8px;
    background: color-mix(in srgb, var(--surface, #181818) 78%, transparent);
}

.scale-advice-grid p,
.scale-advice-tip {
    margin: 5px 0 0;
    color: var(--text, #d0d0d0);
    font-size: 14px;
    line-height: 1.55;
}

.scale-advice-detail {
    border-top: 1px solid color-mix(in srgb, var(--border-soft, #333) 76%, transparent);
    padding-top: 10px;
}

.scale-advice-detail summary {
    cursor: pointer;
    list-style-position: inside;
}

.scale-advice-chord-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 8px;
    margin-top: 10px;
}

.scale-advice-chord-list span {
    color: var(--text, #d0d0d0);
    font-size: 13px;
    line-height: 1.4;
}

.scale-advice-chord-list strong {
    color: var(--gold-light, #c4a484);
    margin-right: 6px;
}

.progression-toolbar {
    display: grid;
    gap: 14px;
    margin-bottom: 16px;
}

.progression-toolbar h4 {
    margin: 0;
}

.progression-toolbar-heading {
    display: flex;
    justify-content: space-between;
    align-items: end;
    gap: 18px;
}

.progression-toolbar-heading p {
    margin: 0;
    color: var(--text-subtle);
    font-size: 13px;
    font-weight: 500;
}

.progression-control-groups {
    display: grid;
    grid-template-columns: minmax(330px, 0.8fr) minmax(0, 1.2fr);
    align-items: start;
    gap: 12px;
}

.progression-control-group {
    min-width: 0;
    overflow: hidden;
    background: var(--subpanel-background);
    border: 1px solid var(--border-soft);
    border-radius: var(--radius);
}

.progression-control-group summary {
    position: relative;
    display: grid;
    gap: 2px;
    padding: 11px 36px 10px 13px;
    color: var(--text-strong);
    cursor: pointer;
    list-style: none;
    user-select: none;
}

.progression-control-group summary::-webkit-details-marker {
    display: none;
}

.progression-control-group summary::after {
    content: "+";
    position: absolute;
    top: 50%;
    right: 14px;
    color: var(--chord-control);
    font-size: 18px;
    line-height: 1;
    transform: translateY(-50%);
}

.progression-control-group[open] summary::after {
    content: "\2212";
}

.progression-control-group summary span {
    font-size: 13px;
    font-weight: 700;
}

.progression-control-group summary small {
    color: var(--text-subtle);
    font-size: 11px;
    font-weight: 500;
}

.progression-control-group summary:hover {
    background: var(--control-hover-background);
}

.progression-control-group summary:focus-visible {
    outline: 3px solid var(--focus-ring);
    outline-offset: -3px;
}

.progression-control-group .progression-controls {
    padding: 12px 13px 13px;
    border-top: 1px solid var(--divider-color);
}

.progression-controls {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 10px;
}

.chord-setting-controls {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.progression-controls.chord-setting-controls label {
    display: grid;
    gap: 6px;
    align-items: stretch;
}

.chord-setting-controls select {
    min-width: 0;
    width: 100%;
}

.playback-controls {
    display: grid;
    grid-template-columns: 1fr;
    gap: 12px;
}

.playback-level-row {
    display: grid;
    grid-template-columns: 82px repeat(2, minmax(145px, 1fr));
    gap: 12px;
    align-items: end;
}

.playback-option-row {
    display: grid;
    grid-template-columns: max-content max-content minmax(180px, 1fr) auto;
    gap: 14px;
    align-items: end;
}

.playback-controls .tempo-control,
.playback-controls .volume-control,
.playback-option-row .band-volume-control {
    display: grid;
    gap: 6px;
}

.playback-controls .tempo-control input[type="number"],
.playback-controls .volume-control input {
    min-width: 0;
    width: 100%;
}

.playback-controls .metronome-toggle,
.playback-controls .backing-toggle {
    align-self: end;
    min-height: 36px;
    white-space: nowrap;
}

.playback-controls #stopProgressionButton {
    align-self: end;
    min-height: 36px;
}

.progression-controls label {
    display: inline-flex;
    align-items: center;
    gap: 7px;
    color: var(--muted);
    font-size: 13px;
    font-weight: bold;
}

.progression-controls input[type="number"] {
    width: 74px;
    min-height: 36px;
    box-sizing: border-box;
    color: var(--text);
    background-color: rgba(20, 20, 20, 0.85);
    border: 1px solid rgba(196, 164, 132, 0.22);
    border-radius: 8px;
    padding: 7px 9px;
    font-family: inherit;
}

.progression-controls input[type="range"] {
    width: 124px;
    accent-color: var(--teal);
}

.volume-control {
    min-height: 36px;
}

.metronome-toggle input,
.backing-toggle input {
    accent-color: var(--teal);
}

.progression-play-button {
    flex-shrink: 0;
    color: #121212;
    background-color: var(--teal);
    border: 1px solid var(--teal);
    border-radius: 999px;
    padding: 8px 13px;
    font-family: inherit;
    font-size: 13px;
    font-weight: bold;
    cursor: pointer;
    transition: transform 0.25s ease, background-color 0.25s ease;
}

.progression-play-button:hover {
    background-color: var(--gold-light);
    transform: translateY(-2px);
}

.note-name {
    display: block;
    color: var(--gold-light);
    font-size: 20px;
    font-weight: bold;
    margin-bottom: 8px;
}

.interval-list {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 6px;
}

.interval-name {
    color: #b8b8b8;
    font-size: 12px;
    line-height: 1.3;
}

.track-card {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
    background-color: #1f1f1f;
    border: 1px solid #333;
    border-left: 5px solid #c4a484;
    border-radius: 10px;
    padding: 16px 18px;
    transition: transform 0.3s ease, border-color 0.3s ease;
}


.track-card:hover {
    transform: translateX(5px);
    border-color: #c4a484;
}

.track-card h5 {
    margin: 0 0 8px;
    color: var(--text);
    font-size: 17px;
}

.track-card p {
    margin: 0;
    color: #aaa;
    font-size: 14px;
}

.track-link {
    flex-shrink: 0;
    color: #121212;
    background-color: #c4a484;
    text-decoration: none;
    font-weight: bold;
    font-size: 14px;
    padding: 8px 14px;
    border-radius: 999px;
    transition: background-color 0.3s ease, transform 0.3s ease;
}

.track-link:hover {
    background-color: #e5d3b3;
    transform: translateY(-2px);
}

.track-link:active {
    transform: translateY(0) scale(0.96);
    background-color: #b39578;
}

.secondary-track-link {
    color: var(--gold);
    background-color: transparent;
    border: 1px solid #c4a484;
}

.secondary-track-link:hover {
    color: #121212;
    background-color: #e5d3b3;
}

.download-track-link {
    color: #e0e0e0;
    background-color: #333;
    border: 1px solid #555;
}

.download-track-link:hover {
    color: #121212;
    background-color: #e5d3b3;
    border-color: #e5d3b3;
}

/* ====================
   圖片與影片設計
   ==================== */
.cover-photo {
    display: block;
    width: 100%;
    max-width: 600px;
    height: auto;
    border-radius: 20px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.5);
    margin: 20px 0;
}


iframe {
    width: 100%;
    aspect-ratio: 16 / 9;
    border-radius: 15px;
    border: none;
    box-shadow: 0 10px 30px rgba(0,0,0,0.5);
}

/* ====================
   純音檔播放器卡片
   ==================== */
.audio-player-card {
    background-color: #2a2a2a;
    padding: 20px;
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.3);
    margin-top: 15px;
    border-left: 5px solid #c4a484;
    transition: transform 0.3s ease;
}

.audio-player-card:hover {
    transform: translateX(5px);
}

.audio-title {
    margin-top: 0;
    margin-bottom: 15px;
    font-weight: bold;
    color: #e0e0e0;
    font-size: 16px;
}

audio {
    width: 100%;
    outline: none;
}

/* ====================
   頁尾 (Footer)
   ==================== */
.footer {
    background-color: #0a0a0a;
    color: #888;
    padding: 30px 0;
    margin-top: 80px;
    font-size: 14px;
    text-align: center;
}

.footer p {
    margin: 0 0 15px;
}

.track-primary-action {
    min-height: 42px;
    padding-inline: 18px;
}

.track-secondary-actions {
    display: grid;
    grid-template-columns: repeat(3, minmax(86px, 1fr));
    align-items: center;
    justify-items: stretch;
    gap: 4px;
    padding-left: 9px;
    border-left: 1px solid var(--border-soft);
}

.track-secondary-action {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 36px;
    min-width: 0;
    padding: 7px 9px;
    border-radius: 6px;
    font-size: 13px;
    line-height: 1;
    text-align: center;
}

.footer .social-links {
    display: flex;
    justify-content: center;
    align-items: center;
    flex-wrap: wrap;
    gap: 12px 20px;
}

.footer .social-links a {
    margin: 0;
    color: var(--teal);
    text-underline-offset: 4px;
}


.footer .social-links a:hover {
    color: #ffffff;
}

/* ====================
   回到頂端按鈕
   ==================== */
#backToTopBtn {
    display: none;
    position: fixed;
    bottom: 40px;
    right: 40px;
    z-index: 99;
    border: none;
    background-color: #c4a484;
    color: #121212;
    cursor: pointer;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    font-size: 24px;
    font-weight: bold;
    box-shadow: 0 4px 15px rgba(0,0,0,0.5);
    transition: background-color 0.3s ease, transform 0.3s ease;
}

#backToTopBtn:hover {
    background-color: #e5d3b3;
    transform: translateY(-5px);
}

@media (max-width: 720px) {
    .progression-category-heading {
        align-items: flex-start;
        flex-direction: column;
        gap: 5px;
        padding-right: 44px;
    }

    .progression-category-meta {
        justify-items: start;
        max-width: none;
    }

    .progression-category-meta span {
        text-align: left;
    }

    .progression-card {
        grid-template-columns: 1fr;
    }

    .progression-card-actions {
        justify-content: flex-start;
        padding-top: 0;
    }

    .scale-advice-grid {
        grid-template-columns: 1fr;
    }
}