:root {
  color-scheme: light;
  --paper: #f4efe6;
  --paper-deep: #e9dfd1;
  --ink: #27231f;
  --muted: #756b61;
  --line: #d7cabc;
  --accent: #b9573f;
  --accent-soft: #ead0c4;
  --card: #fffaf2;
  --shadow: 0 18px 45px rgba(76, 54, 40, .08);
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-width: 320px;
  background: var(--paper);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Yu Gothic", sans-serif;
  line-height: 1.75;
}

body.has-keyboard-dock { padding-bottom: 205px; }
body.has-keyboard-dock.visualizer-collapsed { padding-bottom: 50px; }

a { color: inherit; }

.site-header {
  border-bottom: 1px solid var(--line);
  background: linear-gradient(135deg, #f8f3eb, var(--paper-deep));
}

.site-header-inner, .container { width: min(1180px, calc(100% - 40px)); margin: 0 auto; }
.site-header-inner { padding: 34px 0 30px; }
.site-title-row { display: flex; align-items: end; justify-content: space-between; gap: 24px; }
.site-header h1 { margin: 0; font-family: Georgia, serif; font-size: clamp(1.7rem, 4vw, 2.5rem); letter-spacing: .02em; }
.site-header h1 a { text-decoration: none; }
.tagline { margin: 2px 0 0; color: var(--muted); }
.eyebrow { margin: 0 0 6px; color: var(--accent); font-size: .72rem; font-weight: 700; letter-spacing: .14em; }
.notation-toggle { flex: 0 0 auto; padding: 8px 12px; border: 1px solid var(--line); border-radius: 999px; background: var(--card); color: var(--ink); cursor: pointer; font: inherit; font-size: .82rem; }
.notation-toggle:hover, .notation-toggle[aria-pressed="true"] { border-color: var(--accent); background: var(--accent); color: white; }
.panel-toggle { padding: 7px 10px; border: 1px solid var(--line); border-radius: 7px; background: transparent; color: var(--muted); cursor: pointer; font: inherit; font-size: .75rem; white-space: nowrap; }
.panel-toggle:hover { border-color: var(--accent); color: var(--accent); }
.site-header.is-collapsed .site-header-inner { padding-top: 8px; padding-bottom: 8px; }
.site-header.is-collapsed .eyebrow, .site-header.is-collapsed .tagline { display: none; }
.site-header.is-collapsed h1 { font-size: 1.05rem; }

.hero { max-width: 660px; padding: 72px 0 42px; }
.hero h2 { margin: 0 0 14px; font-family: Georgia, serif; font-size: clamp(2.1rem, 6vw, 4rem); line-height: 1.16; font-weight: 500; }
.hero p:last-child { max-width: 500px; color: var(--muted); font-size: 1.05rem; }

.controls { display: grid; grid-template-columns: auto minmax(200px, 1fr); gap: 12px 16px; align-items: center; margin: 8px 0 18px; }
.search-label { color: var(--muted); font-size: .85rem; }
input[type="search"] { width: 100%; padding: 12px 15px; border: 1px solid var(--line); border-radius: 8px; background: var(--card); color: var(--ink); font: inherit; }
input[type="search"]:focus { outline: 2px solid var(--accent-soft); border-color: var(--accent); }
.filters { grid-column: 1 / -1; display: grid; gap: 10px; }
.filter-group { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; }
.filter-heading { width: 54px; color: var(--muted); font-size: .78rem; font-weight: 700; }
.filter { padding: 7px 12px; border: 1px solid var(--line); border-radius: 999px; background: transparent; color: var(--muted); cursor: pointer; font: inherit; font-size: .86rem; }
.filter.active, .filter:hover { border-color: var(--accent); background: var(--accent); color: white; }
.filter span { padding-left: 2px; font-size: .72em; opacity: .7; }
.result-count { color: var(--muted); font-size: .85rem; }

.catalog { padding-bottom: 60px; }
.catalog-section { margin: 34px 0 48px; }
.catalog-heading { display: flex; align-items: baseline; justify-content: space-between; gap: 16px; margin-bottom: 14px; padding-bottom: 8px; border-bottom: 1px solid var(--line); }
.catalog-heading h3 { margin: 0; font-family: Georgia, serif; font-size: 1.35rem; font-weight: 500; }
.catalog-heading span { color: var(--muted); font-size: .78rem; }
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(270px, 1fr)); gap: 18px; }
.card { display: block; min-height: 235px; padding: 24px; border: 1px solid var(--line); border-radius: 12px; background: var(--card); box-shadow: var(--shadow); text-decoration: none; transition: transform .18s ease, border-color .18s ease; }
.card:hover { transform: translateY(-3px); border-color: var(--accent); }
.tool-card { border-color: var(--accent-soft); background: linear-gradient(145deg, var(--card), #f7e7dc); }
.card-kind { color: var(--accent); font-size: .77rem; font-weight: 700; letter-spacing: .08em; }
.card h2 { margin: 10px 0 10px; font-family: Georgia, serif; font-size: 1.45rem; line-height: 1.35; }
.card p { margin: 0 0 18px; color: var(--muted); font-size: .92rem; }
.tags { display: flex; flex-wrap: wrap; gap: 6px; }
.tag { padding: 2px 8px; border-radius: 999px; background: var(--accent-soft); color: #723626; font-size: .74rem; }

.detail { padding-top: 34px; padding-bottom: 80px; }
.back-link { display: inline-block; margin-bottom: 30px; color: var(--accent); font-size: .9rem; text-decoration: none; }
.back-link:hover { text-decoration: underline; }
.detail article { max-width: 1180px; }
.detail-header { padding: 28px 0 34px; border-bottom: 1px solid var(--line); }
.detail-header h2 { margin: 0 0 12px; font-family: Georgia, serif; font-size: clamp(2rem, 5vw, 3.5rem); line-height: 1.2; font-weight: 500; }
.lead { max-width: 700px; margin: 0 0 18px; color: var(--muted); font-size: 1.05rem; }
.knowledge-section { margin-top: 42px; }
.knowledge-section h3 { margin: 0 0 15px; font-size: 1rem; letter-spacing: .08em; }
.diatonic-controls { display: flex; flex-wrap: wrap; gap: 12px; padding: 16px; border: 1px solid var(--line); border-radius: 10px; background: var(--card); }
.diatonic-controls label { display: flex; flex-direction: column; gap: 4px; color: var(--muted); font-size: .78rem; }
.converter-controls { display: grid; grid-template-columns: repeat(3, minmax(160px, 1fr)); gap: 12px; padding: 16px; border: 1px solid var(--line); border-radius: 10px; background: var(--card); }
.converter-controls label { display: flex; flex-direction: column; gap: 4px; color: var(--muted); font-size: .78rem; }
.converter-input-label { grid-column: 1 / -1; }
.converter-controls textarea { grid-column: 1 / -1; width: 100%; min-height: 76px; padding: 10px 12px; border: 1px solid var(--line); border-radius: 7px; background: var(--paper); color: var(--ink); font: inherit; resize: vertical; }
.converter-controls textarea:focus { outline: 2px solid var(--accent-soft); border-color: var(--accent); }
.converter-controls #converter-run { justify-self: start; }
.converter-result { margin-top: 22px; padding: 18px; border: 1px solid var(--line); border-radius: 10px; background: var(--paper); }
.converter-result h3 { margin: 0 0 10px; }
.converter-result output { display: flex; flex-wrap: wrap; align-items: center; gap: 5px; min-height: 42px; color: var(--accent); font-family: Georgia, serif; font-size: 1.2rem; }
.converter-separator { color: var(--muted); }
.converter-degree { white-space: nowrap; }
.converter-invalid { color: var(--muted); font-family: inherit; font-size: .9rem; }
select { min-width: 150px; padding: 9px 30px 9px 10px; border: 1px solid var(--line); border-radius: 7px; background: var(--paper); color: var(--ink); font: inherit; }
.tool-caption { margin: 16px 0 12px; color: var(--accent); font-family: Georgia, serif; font-size: 1.15rem; }
.mode-note { margin: -4px 0 14px; color: var(--muted); font-size: .84rem; }
.scale { display: flex; flex-wrap: wrap; gap: 8px; }
.scale-note { min-width: 48px; padding: 11px 14px; border: 1px solid var(--line); border-radius: 8px; background: var(--card); text-align: center; font-family: Georgia, serif; font-size: 1.25rem; }
.inline-note { padding: 1px 3px; border: 0; border-radius: 4px; background: transparent; color: inherit; cursor: pointer; font: inherit; }
.inline-note:hover, .inline-note:focus-visible, .inline-note.is-playing { background: var(--accent-soft); color: #723626; outline: none; }
.note-symbol { display: inline-block; }
.function-legend { display: flex; flex-wrap: wrap; gap: 8px; margin: -2px 0 13px; }
.function-badge { display: inline-flex; align-items: center; padding: 3px 9px; border-left: 4px solid currentColor; border-radius: 4px; background: #f0ebe4; font-size: .78rem; font-weight: 700; }
.function-tonic { color: #36737b; background: #deedf0; }
.function-subdominant { color: #a47728; background: #f4eacb; }
.function-dominant { color: #a44c45; background: #f2dcd7; }
.function-modal { color: #76549a; background: #e9def3; }
.table-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: 10px; background: var(--card); }
table { width: 100%; border-collapse: collapse; min-width: 680px; }
th, td { padding: 13px 14px; border-bottom: 1px solid var(--line); text-align: left; white-space: nowrap; }
thead th { background: var(--paper-deep); color: var(--muted); font-size: .78rem; }
tbody tr:last-child th, tbody tr:last-child td { border-bottom: 0; }
.root, .chord { font-family: Georgia, serif; font-size: 1.1rem; }
.chord { color: var(--accent); font-weight: 700; }
.chord.play-chord { display: inline-flex; align-items: baseline; padding: 3px 5px; border: 1px solid transparent; border-radius: 5px; background: transparent; cursor: pointer; font: inherit; color: inherit; }
.chord.play-chord:hover, .chord.play-chord.is-playing { border-color: var(--accent); background: var(--accent-soft); }
.play-chord { padding: 6px 9px; border: 1px solid var(--line); border-radius: 6px; background: transparent; color: var(--muted); cursor: pointer; font: inherit; font-size: .8rem; }
.play-chord:hover, .play-chord.is-playing { border-color: var(--accent); background: var(--accent); color: white; }
.audio-note { margin: 16px 0 0; color: var(--muted); font-size: .82rem; }
.progression-controls { position: sticky; top: 0; z-index: 10; display: grid; grid-template-columns: auto minmax(220px, 1fr) auto; gap: 12px 16px; align-items: center; padding: 16px; border: 1px solid var(--line); border-radius: 10px; background: rgba(255, 250, 242, .96); box-shadow: 0 8px 20px rgba(76, 54, 40, .08); backdrop-filter: blur(8px); }
.progression-controls label:not(.search-label) { display: flex; align-items: center; gap: 8px; color: var(--muted); font-size: .82rem; }
.progression-controls select { min-width: 88px; }
.progression-filter-group { grid-column: 1 / -1; display: flex; flex-wrap: wrap; align-items: center; gap: 8px; }
.progression-list { display: grid; grid-template-columns: 1fr; gap: 12px; margin-top: 18px; }
.progression-card { display: grid; grid-template-columns: minmax(170px, .8fr) minmax(260px, 1.3fr) minmax(240px, 1fr) auto; grid-template-areas: "heading line use play" "title line concrete play" "info info info info"; column-gap: 18px; align-items: center; min-height: 0; padding: 16px 20px; border: 1px solid var(--line); border-radius: 10px; background: var(--card); box-shadow: var(--shadow); }
.progression-heading { grid-area: heading; }
.progression-card h3 { grid-area: title; }
.progression-line { grid-area: line; }
.progression-use { grid-area: use; min-height: 0; }
.progression-concrete { grid-area: concrete; min-height: 0; }
.progression-play { grid-area: play; }
.progression-info { grid-area: info; }
.progression-card h3 { margin: 8px 0 14px; font-family: Georgia, serif; font-size: 1.15rem; line-height: 1.45; letter-spacing: 0; }
.progression-heading { display: flex; align-items: baseline; justify-content: space-between; gap: 10px; }
.progression-number { color: var(--accent); font-family: Georgia, serif; font-size: 1.08rem; font-weight: 700; }
.progression-group { color: var(--muted); font-size: .74rem; }
.progression-line { display: flex; flex-wrap: wrap; align-items: center; gap: 2px; padding: 12px 10px; border: 1px solid var(--line); border-radius: 7px; background: var(--paper); color: var(--ink); font-family: Georgia, serif; font-size: 1.12rem; }
.progression-step { white-space: nowrap; }
.progression-separator { color: var(--muted); }
.progression-use { margin: 0; color: var(--muted); font-size: .8rem; line-height: 1.6; }
.ratings { display: flex; flex-wrap: wrap; gap: 5px; margin-top: 7px; }
.rating { padding: 1px 6px; border-radius: 4px; background: var(--paper-deep); font-size: .7rem; }
.rating b { color: var(--accent); }
.progression-concrete { margin: 0; color: var(--muted); font-size: .82rem; line-height: 1.6; }
.progression-play { align-self: flex-start; margin-top: 0; padding: 7px 12px; border: 1px solid var(--line); border-radius: 999px; background: transparent; color: var(--muted); cursor: pointer; font: inherit; font-size: .82rem; }
.progression-play:hover, .progression-play.is-playing { border-color: var(--accent); background: var(--accent); color: white; }
.progression-info { margin-top: 15px; padding-top: 12px; border-top: 1px solid var(--line); color: var(--muted); font-size: .82rem; line-height: 1.7; }
.progression-info summary { color: var(--accent); cursor: pointer; font-weight: 700; }
.progression-info summary:hover { text-decoration: underline; }
.progression-info h4 { margin: 15px 0 4px; color: var(--ink); font-size: .78rem; letter-spacing: .05em; }
.progression-info p { margin: 8px 0; }
.progression-info ul { margin: 5px 0 0; padding-left: 1.2em; }
.progression-info li { margin: 5px 0; }
.progression-source-chord { padding: 8px 10px; border-radius: 6px; background: var(--paper); }
.youtube-embed { margin: 4px 0; }
.youtube-embed summary { display: flex; align-items: baseline; justify-content: space-between; gap: 10px; cursor: pointer; }
.youtube-embed summary:hover { text-decoration: underline; }
.youtube-open { flex: 0 0 auto; color: var(--accent); font-size: .75rem; }
.youtube-frame { aspect-ratio: 16 / 9; max-width: 680px; margin-top: 8px; background: #1f1b19; }
.youtube-frame iframe { width: 100%; height: 100%; border: 0; }
.youtube-source { display: inline-block; margin-top: 4px; color: var(--muted); font-size: .72rem; }
.youtube-link { text-decoration: none; }
.youtube-link:hover { text-decoration: underline; }
.youtube-missing { color: var(--muted); }
.sheet-music-block { margin-top: 18px; padding: 12px; border: 1px solid var(--line); border-radius: 8px; background: var(--paper); }
.sheet-music-note { margin: 0 0 8px !important; font-size: .75rem; }
.sheet-music { min-height: 80px; overflow-x: auto; color: var(--ink); }
.fifths-note { margin: -5px 0 12px; color: var(--muted); font-size: .8rem; }
.fifths-wheel { --fifths-radius: min(34vw, 126px); --fifths-minor-radius: min(22vw, 82px); position: relative; width: min(100%, 360px); aspect-ratio: 1; margin: 0 auto; border: 1px solid var(--line); border-radius: 50%; background: radial-gradient(circle, var(--card) 0 22%, var(--line) 22.5% 23%, var(--paper-deep) 23.5% 57%, var(--line) 57.5% 58%, var(--paper-deep) 58.5%), var(--paper-deep); }
.fifths-wheel::before { position: absolute; inset: 23%; border: 1px dashed var(--line); border-radius: 50%; content: ""; }
.fifths-center { position: absolute; top: 50%; left: 50%; z-index: 1; display: flex; flex-direction: column; transform: translate(-50%, -50%); color: var(--muted); font-size: .7rem; line-height: 1.4; text-align: center; }
.fifths-node { position: absolute; top: 50%; left: 50%; display: inline-flex; width: 54px; height: 36px; align-items: center; justify-content: center; padding: 3px 5px; border: 1px solid var(--line); border-radius: 999px; background: var(--card); color: var(--ink); font: inherit; font-family: Georgia, serif; font-size: 1rem; cursor: pointer; transform: translate(-50%, -50%) rotate(calc(var(--fifths-index) * 30deg)) translateY(calc(-1 * var(--fifths-radius))) rotate(calc(var(--fifths-index) * -30deg)); transition: background .15s ease, color .15s ease, box-shadow .15s ease; }
.fifths-minor { width: 44px; height: 30px; font-size: .82rem; transform: translate(-50%, -50%) rotate(calc(var(--fifths-index) * 30deg)) translateY(calc(-1 * var(--fifths-minor-radius))) rotate(calc(var(--fifths-index) * -30deg)); }
.fifths-node:hover, .fifths-node:focus-visible { border-color: var(--accent); outline: none; }
.fifths-node.is-active { border-color: var(--accent); background: var(--accent); color: white; box-shadow: 0 0 0 5px rgba(185, 87, 63, .22), 0 0 18px rgba(185, 87, 63, .32); }
.fifths-minor.is-active { background: #8a6aa5; }
.keyboard-note { margin: -5px 0 12px; color: var(--muted); font-size: .8rem; }
.keyboard-heading { display: flex; flex-wrap: wrap; align-items: center; gap: 6px 12px; margin: 0 0 8px; }
.keyboard-heading h3 { margin: 0; }
.keyboard-heading .keyboard-note { margin: 0; }
.voicing-control { display: inline-flex; align-items: center; gap: 6px; color: var(--muted); font-size: .78rem; }
.voicing-control select { min-width: 132px; padding: 4px 24px 4px 8px; font-size: .8rem; }
.visualizer-dock { position: fixed; z-index: 20; right: 0; bottom: 0; left: 0; width: 100%; padding: 8px max(20px, calc((100% - 1060px) / 2)); border-top: 1px solid var(--line); background: rgba(244, 239, 230, .96); box-shadow: 0 -10px 28px rgba(76, 54, 40, .12); backdrop-filter: blur(8px); }
.visualizer-content { display: grid; grid-template-columns: minmax(150px, 220px) minmax(0, 1fr); min-height: 160px; }
.visualizer-toggle { position: absolute; top: 5px; right: max(20px, calc((100% - 1180px) / 2)); z-index: 1; }
.visualizer-dock.is-collapsed { padding-top: 4px; padding-bottom: 4px; }
.visualizer-dock.is-collapsed .visualizer-content { display: none; }
.visualizer-dock.is-collapsed .visualizer-toggle { position: static; display: block; width: 100%; }
.fifths-dock { min-width: 0; padding-right: 14px; border-right: 1px solid var(--line); }
.fifths-dock .fifths-section { margin: 0; }
.fifths-dock .fifths-section h3 { display: inline-block; margin: 0 0 4px; font-size: .78rem; }
.fifths-dock .fifths-note { display: none; }
.fifths-dock .fifths-wheel { --fifths-radius: 53px; --fifths-minor-radius: 30px; width: min(100%, 150px); margin: 0 auto; }
.fifths-dock .fifths-node { width: 40px; height: 27px; font-size: .76rem; }
.fifths-dock .fifths-minor { width: 33px; height: 23px; font-size: .62rem; }
.keyboard-dock { min-width: 0; padding-left: 14px; }
.visualizer-dock .keyboard-section { margin: 0; }
.visualizer-dock .keyboard-section h3 { display: inline-block; margin: 0; font-size: .78rem; }
.visualizer-dock .keyboard-heading { margin: 0 0 4px; }
.visualizer-dock .keyboard-note { display: inline; margin: 0; }
.keyboard { display: grid; grid-template-columns: repeat(24, minmax(30px, 1fr)); gap: 3px; min-height: 108px; padding: 8px; border: 1px solid var(--line); border-radius: 10px; background: var(--paper-deep); overflow-x: auto; }
.piano-key { display: flex; min-height: 100px; align-items: end; justify-content: center; padding: 9px 1px; border: 1px solid #c7b9a9; border-radius: 0 0 6px 6px; background: #fffdf8; color: var(--ink); cursor: pointer; font: inherit; font-size: .72rem; }
.piano-key.black { min-height: 72px; align-self: start; border-color: #302923; background: #39302b; color: #fffaf2; }
.piano-key:hover, .piano-key.is-playing { outline: 2px solid var(--accent); outline-offset: 1px; }
.piano-key.is-active { background: #e9b84f; color: #4c3210; box-shadow: inset 0 -7px 0 #c68e22; }
.piano-key.black.is-active { background: #d98547; color: white; box-shadow: inset 0 -7px 0 #a84d2b; }
.note-section li { margin: 8px 0; }
.related-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); gap: 12px; }
.related-card { display: flex; flex-direction: column; gap: 3px; padding: 14px 16px; border: 1px solid var(--line); border-radius: 9px; background: var(--card); text-decoration: none; }
.related-card:hover { border-color: var(--accent); }
.related-card span { color: var(--accent); font-size: .75rem; }
.related-card strong { font-family: Georgia, serif; font-weight: 500; }
.source { margin-top: 42px; color: var(--muted); font-size: .8rem; }
.site-footer { padding: 22px 20px; border-top: 1px solid var(--line); color: var(--muted); text-align: center; font-size: .78rem; }

.is-hidden { display: none !important; }
.catalog-section.is-empty { display: none; }

@media (max-width: 600px) {
  body.has-keyboard-dock { padding-bottom: 155px; }
  body.has-keyboard-dock.visualizer-collapsed { padding-bottom: 50px; }
  .site-header-inner, .container { width: min(100% - 28px, 1180px); }
  .site-header-inner { padding: 24px 0; }
  .site-title-row { align-items: start; flex-direction: column; gap: 12px; }
  .hero { padding-top: 48px; }
  .controls { grid-template-columns: 1fr; }
  .search-label { display: none; }
  .progression-controls { grid-template-columns: 1fr; }
  .progression-filter-group { grid-column: auto; }
  .progression-controls label:not(.search-label) { justify-content: space-between; }
  .converter-controls { grid-template-columns: 1fr; }
  .converter-input-label { grid-column: auto; }
  .converter-controls textarea { grid-column: auto; }
  .progression-card { display: flex; min-height: 0; flex-direction: column; padding: 18px; }
  .progression-card h3 { margin: 8px 0 14px; }
  .progression-use { margin: 12px 0 0; }
  .progression-concrete { margin: 12px 0; }
  .visualizer-dock { padding: 6px 10px; }
  .visualizer-content { grid-template-columns: 116px minmax(0, 1fr); min-height: 110px; }
  .visualizer-toggle { right: 10px; }
  .fifths-dock { padding-right: 8px; }
  .fifths-dock .fifths-wheel { --fifths-radius: 37px; --fifths-minor-radius: 21px; width: 104px; }
  .fifths-dock .fifths-node { width: 31px; height: 23px; font-size: .62rem; }
  .fifths-dock .fifths-minor { width: 26px; height: 19px; font-size: .52rem; }
  .keyboard-dock { padding-left: 8px; }
  .visualizer-dock .keyboard-note { display: none; }
  .keyboard { grid-template-columns: repeat(24, minmax(20px, 1fr)); min-height: 84px; padding: 6px; gap: 2px; }
  .piano-key { min-height: 76px; padding: 6px 1px; font-size: .58rem; }
  .piano-key.black { min-height: 52px; }
  .voicing-control select { min-width: 108px; }
}