:root {
  --bg: #fbfaf7;
  --surface: #ffffff;
  --text: #1f1d1a;
  --muted: #6f6a62;
  --line: #d9d4ca;
  --accent: #c2410c;
  --accent-contrast: #ffffff;
  --dot: #2b2824;
  --dot-text: #ffffff;
  --easy: #15803d;
  --improver: #4d7c0f;
  --medium: #b45309;
  --hard: #b91c1c;
  color-scheme: light;

  /* Layout: one content width and one set of control sizes for every block. */
  --content: 960px;
  --gutter: 16px;
  --control-h: 36px;
  --chip-h: 32px;
  --radius: 8px;
  --label-col: 3.5rem;   /* row labels on the chord page (Root / Type / Bass) */
  --score-col: 11em;     /* level + effort column in ranking and top-3 rows */
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #161513;
    --surface: #211f1c;
    --text: #ece8e1;
    --muted: #a39d93;
    --line: #45413b;
    --accent: #fb923c;
    --accent-contrast: #1b1107;
    --dot: #ece8e1;
    --dot-text: #161513;
    --easy: #4ade80;
    --improver: #bef264;
    --medium: #fbbf24;
    --hard: #f87171;
    color-scheme: dark;
  }
}

/* ---- Base ---------------------------------------------------------------- */
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 15px/1.45 system-ui, -apple-system, "Segoe UI", sans-serif;
}
header, main, footer {
  max-width: calc(var(--content) + 2 * var(--gutter));
  margin: 0 auto;
  padding: 0 var(--gutter);
}
header { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 20px; padding-top: 20px; padding-bottom: 16px; }
h1 { font-size: 1.35rem; margin: 0; letter-spacing: -0.01em; display: flex; align-items: center; gap: 0.35em; }
/* Sized in em so the pick scales with the title. */
h1 .logo { width: 1.3em; height: 1.3em; flex: none; }
h2 { font-size: 1.15rem; margin: 0; }
.visually-hidden { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); }
.hint { color: var(--muted); font-size: 0.88rem; margin: 4px 0 0; }
.empty { color: var(--muted); }
.optional { opacity: 0.5; }
.tab { font-family: ui-monospace, "Cascadia Mono", Consolas, monospace; font-size: 0.95rem; letter-spacing: 0.06em; }

nav { display: flex; gap: 4px; }
nav a { padding: 4px 10px; border: 1px solid transparent; border-radius: var(--radius); color: var(--muted); text-decoration: none; }
nav a:hover { color: var(--text); }
nav a[aria-current="page"] { color: var(--text); background: var(--surface); border-color: var(--line); }

footer { color: var(--muted); font-size: 0.85rem; padding-bottom: 24px; }
footer > * { border-top: 1px solid var(--line); padding-top: 12px; }
footer > * + * { border-top: 0; padding-top: 0; }

/* ---- Form controls ------------------------------------------------------- */
/* minmax(0, …): the song picker is as wide as its longest title and must not widen the form. */
.entry { display: grid; grid-template-columns: minmax(0, 1fr); gap: 10px; margin: 0 0 20px; }
.field { display: flex; flex-direction: column; gap: 4px; min-width: 0; font-size: 0.8rem; color: var(--muted); }
.field input, .field select {
  width: 100%; height: var(--control-h); padding: 0 10px;
  font: inherit; font-size: 0.95rem; color: var(--text);
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius);
}
.field.wide input { height: 42px; padding: 0 12px; font-size: 1.1rem; }
/* Label on the left, Copy link on the right, sized like the example chips so the row stays short. */
.field-head { display: flex; align-items: center; gap: 8px 12px; }
.label-group { position: relative; display: inline-flex; align-items: center; gap: 6px; }
/* A small round "i"; its hint pops up under it on hover, keyboard focus, or a tap. */
.info {
  width: 18px; height: 18px; padding: 0; font: inherit; font-size: 0.7rem; font-weight: 700; font-style: italic; line-height: 1;
  color: var(--muted); background: none; border: 1px solid var(--line); border-radius: 50%; cursor: help;
}
.info:hover, .info:focus-visible, .info[aria-expanded="true"] { color: var(--text); border-color: var(--accent); }
.hint-pop {
  display: none; position: absolute; top: calc(100% + 6px); left: 0; z-index: 10; width: max-content; max-width: min(420px, 80vw);
  padding: 8px 12px; font-size: 0.85rem; line-height: 1.45; color: var(--text);
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); box-shadow: 0 4px 16px rgba(0, 0, 0, 0.25);
}
.info:hover + .hint-pop, .info:focus-visible + .hint-pop, .hint-pop.open { display: block; }
.field-head .song-pick { flex: 1; min-width: 0; }
/* Wide enough for the longest title, not the whole row. */
.field-head .song-pick select { max-width: 24rem; }
.field-head .copy-link { margin-left: auto; }
.icon-btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 4px;
  padding: 4px 6px; font: inherit; font-size: 0.8rem; color: var(--muted);
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); cursor: pointer;
}
.icon-btn:hover { color: var(--text); border-color: var(--accent); }
.icon-btn.done { color: var(--easy); border-color: var(--easy); }
/* The chosen key's chords as text, under the arrangement heading. */
.chord-line { display: flex; flex-wrap: wrap; align-items: center; gap: 6px 12px; margin: 6px 0 0; }
.chord-text { font-size: 1.05rem; word-break: break-word; }
.chord-text small { color: var(--muted); font-size: 0.8rem; }
.field input:focus, .field select:focus { outline: 2px solid var(--accent); outline-offset: 1px; }
.field input.invalid { border-color: var(--hard); }

.song-pick { display: inline-flex; align-items: center; gap: 6px; font-size: 0.8rem; color: var(--muted); }
.song-pick select {
  min-width: 0; padding: 2px 6px; font: inherit; color: var(--text);
  background: var(--surface); border: 1px solid var(--line); border-radius: 999px; cursor: pointer;
}
.song-pick select:hover { border-color: var(--accent); }

/* Options fill the same width as the input above them. */
/* min(…, 100%) keeps a column from ever being wider than a small phone. */
/* auto-fill, not auto-fit: two or three fields keep their column width instead of stretching. */
.options { display: grid; grid-template-columns: repeat(auto-fill, minmax(min(130px, 100%), 1fr)); gap: 12px; margin-top: 4px; }
.more-toggle {
  align-self: end; height: var(--control-h); padding: 0 12px; font: inherit; font-size: 0.9rem; color: var(--text);
  background: none; border: 1px dashed var(--line); border-radius: var(--radius); cursor: pointer; white-space: nowrap;
}
.more-toggle:hover { border-color: var(--accent); }
#more-summary { margin: 0; }
#more-summary:empty { display: none; }
.more-options { display: grid; gap: 10px; }
.more-options[hidden] { display: none; }
.checks { display: flex; flex-wrap: wrap; gap: 6px 20px; font-size: 0.9rem; }
.checks label { display: inline-flex; align-items: center; gap: 6px; }
.checks input { margin: 0; accent-color: var(--accent); }
.error { color: var(--hard); margin: 0; min-height: 1em; font-size: 0.88rem; }
.error:empty, #prog-note:empty { display: none; }
/* Shown instead of the page when it can't run: no JavaScript, or too old a browser. */
.unsupported main > :not(.notice), .unsupported footer { display: none !important; }
.notice .error-detail { display: block; margin-top: 6px; color: var(--muted); font-family: ui-monospace, Consolas, monospace; font-size: 0.8rem; }
.notice {
  margin: 8px 0 16px; padding: 12px var(--gutter);
  background: var(--surface); border: 1px solid var(--line); border-left: 4px solid var(--accent);
  border-radius: var(--radius);
}

/* ---- Chord page pickers -------------------------------------------------- */
.pickers { display: grid; gap: 10px; margin: 0 0 24px; }
.picker-row { display: grid; grid-template-columns: var(--label-col) minmax(0, 1fr); gap: 12px; align-items: start; }
.row-label {
  font-size: 0.75rem; text-transform: uppercase; letter-spacing: 0.06em; color: var(--muted);
  line-height: var(--chip-h);
}
.picker { display: flex; flex-wrap: wrap; gap: 6px; }
.picker button, .picker select {
  height: var(--chip-h); min-width: 40px; padding: 0 9px;
  font: inherit; font-size: 0.9rem; color: var(--text);
  background: var(--surface); border: 1px solid var(--line); border-radius: 6px; cursor: pointer;
}
.picker button:hover, .picker select:hover { border-color: var(--accent); }
/* Segmented Auto / ♭ / ♯ control at the end of the root row. */
.seg { display: inline-flex; margin-left: auto; }
.picker .seg button { min-width: 0; border-radius: 0; margin-left: -1px; }
.picker .seg button:first-child { border-radius: 6px 0 0 6px; margin-left: 0; }
.picker .seg button:last-child { border-radius: 0 6px 6px 0; }
.picker .seg button[aria-pressed="true"] { position: relative; }
.picker button[aria-pressed="true"], .picker select.active { background: var(--accent); border-color: var(--accent); color: var(--accent-contrast); }
.picker select option, .picker select optgroup { background: var(--surface); color: var(--text); }

#chord-info h2 { margin: 0 0 6px; font-size: 1.8rem; }
#chord-info h2 small { font-size: 1rem; font-weight: 400; color: var(--muted); margin-left: 6px; }
#chord-info dl { display: flex; flex-wrap: wrap; gap: 6px 28px; margin: 0; }
#chord-info dt { font-size: 0.75rem; text-transform: uppercase; letter-spacing: 0.06em; color: var(--muted); }
#chord-info dd { margin: 0; font-size: 1.05rem; word-spacing: 0.3em; }

/* ---- Voicing cards and diagrams ----------------------------------------- */
.voicing-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(min(150px, 100%), 1fr));
  gap: 12px; margin: 20px 0 24px;
}
.voicing {
  margin: 0; padding: 10px 8px 12px; background: var(--surface);
  border: 1px solid var(--line); border-radius: 10px;
  display: flex; flex-direction: column; align-items: center;
}
.voicing.differs { border-color: var(--accent); }
.voicing figcaption { display: flex; flex-direction: column; align-items: center; gap: 2px; text-align: center; font-size: 0.82rem; }
.shape, .reasons { color: var(--muted); }
.reasons { font-size: 0.75rem; }

.badge { font-size: 0.72rem; font-weight: 600; text-transform: uppercase; letter-spacing: 0.05em; }
.badge.beginner { color: var(--easy); }
.badge.improver { color: var(--improver); }
.badge.intermediate { color: var(--medium); }
.badge.advanced { color: var(--hard); }

.chord-diagram { overflow: visible; }
.chord-diagram .string, .chord-diagram .fret { stroke: var(--line); stroke-width: 1.2; }
.chord-diagram .string { stroke: var(--muted); stroke-width: 1; }
.chord-diagram .nut { stroke: var(--text); stroke-width: 4; }
.chord-diagram .dot, .chord-diagram .barre { fill: var(--dot); }
.chord-diagram .dot.root { fill: var(--accent); }
.chord-diagram .open { fill: none; stroke: var(--text); stroke-width: 1.4; }
.chord-diagram .open.root { stroke: var(--accent); stroke-width: 2; }
.chord-diagram .finger { fill: var(--dot-text); font-size: 10px; font-weight: 700; }
.chord-diagram .dot.root + .finger { fill: var(--accent-contrast); }
.chord-diagram .marker { fill: var(--muted); font-size: 14px; }
.chord-diagram .fret-label { fill: var(--muted); font-size: 11px; }
.chord-diagram .note-name { fill: var(--muted); font-size: 10px; }

/* ---- Progression page: harmony ------------------------------------------- */
/* Folded section holding harmony and scales. */
.theory { margin: 0 0 32px; }
.theory > summary { cursor: pointer; padding: 10px 0; border-top: 1px solid var(--line); }
.theory > summary .theory-title { font-size: 1.15rem; font-weight: 700; }
.theory > summary .hint { display: inline; margin: 0 0 0 6px; }
.theory[open] > summary { margin-bottom: 12px; }
#harmony { margin: 0 0 28px; }
#harmony:empty { display: none; }
.h-flow { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 4px; margin-top: 12px; }
.h-chord {
  display: flex; flex-direction: column; align-items: center; min-width: 76px; padding: 6px 10px 7px;
  background: var(--surface); border: 1px solid var(--line); border-top: 3px solid var(--line); border-radius: var(--radius);
}
.h-chord.fn-T { border-top-color: var(--easy); }
.h-chord.fn-S { border-top-color: var(--medium); }
.h-chord.fn-D { border-top-color: var(--hard); }
.h-chord.secondary, .h-chord.borrowed, .h-chord.chromatic, .h-chord.tonicized { border-style: dashed; border-top-style: solid; }
.h-sym { font-size: 0.8rem; color: var(--muted); }
.h-num { font-size: 1.25rem; font-weight: 700; font-family: Georgia, "Times New Roman", serif; line-height: 1.2; }
.h-fn { font-size: 0.7rem; color: var(--muted); text-transform: uppercase; letter-spacing: 0.04em; }
.h-move { display: flex; flex-direction: column; align-items: center; min-width: 30px; font-size: 0.8rem; color: var(--muted); }
.h-move.strong { color: var(--easy); font-weight: 700; }
.h-move small { font-size: 0.65rem; }
.h-key { display: flex; flex-wrap: wrap; gap: 4px 16px; margin: 10px 0 0; font-size: 0.78rem; color: var(--muted); }
.h-key span::before { content: ""; display: inline-block; width: 14px; height: 3px; margin-right: 6px; vertical-align: middle; background: var(--line); }
.h-key .k-T::before { background: var(--easy); }
.h-key .k-S::before { background: var(--medium); }
.h-key .k-D::before { background: var(--hard); }
.h-key .k-out::before { background: none; border-top: 2px dashed var(--muted); height: 0; }
.h-key span:last-child::before { display: none; }
.h-key b { color: var(--easy); }
.h-notes { margin: 12px 0 0; padding-left: 18px; font-size: 0.88rem; color: var(--muted); }
.h-notes li { margin: 2px 0; }
.h-notes strong { color: var(--text); }

/* ---- Progression page: rankings ----------------------------------------- */
.rankings { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(340px, 100%), 1fr)); gap: 20px 24px; }
.rankings h2 { margin-bottom: 8px; cursor: help; }
.rankings h2 small { font-size: 0.8rem; font-weight: 400; color: var(--muted); }
.options-list li.after-gap { margin-top: 10px; }
.show-all {
  margin-top: 6px; padding: 2px 10px; font: inherit; font-size: 0.8rem; color: var(--muted);
  background: none; border: 1px dashed var(--line); border-radius: 999px; cursor: pointer;
}
.show-all:hover { color: var(--text); border-color: var(--accent); }
.show-all[hidden] { display: none; }
.options-list, .alts { list-style: none; margin: 0; padding: 0; display: grid; gap: 4px; }

/* Ranking rows and top-3 rows share one look and one score column. */
.option, .alt {
  width: 100%; display: grid; gap: 10px; align-items: center;
  min-height: 40px; padding: 5px 10px;
  font: inherit; font-size: 0.88rem; text-align: left; color: var(--text);
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); cursor: pointer;
}
.option { grid-template-columns: 5.5em minmax(0, 1fr) var(--score-col); }
.alt { grid-template-columns: 2em minmax(0, 1fr) var(--score-col); }
.option:hover, .alt:hover { border-color: var(--accent); }
.option[aria-pressed="true"], .alt[aria-pressed="true"] { border-color: var(--accent); box-shadow: inset 3px 0 0 var(--accent); }
.option.infeasible { color: var(--muted); }
.option.infeasible .opt-score { justify-content: flex-end; white-space: normal; text-align: right; }

.opt-label { font-weight: 600; line-height: 1.2; }
.opt-label small { display: block; font-weight: 400; color: var(--muted); font-size: 0.75rem; }
.opt-chords { color: var(--muted); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.opt-chords s { opacity: 0.6; }

/* Level on the left, effort on the right, same position in every row. */
.opt-score, .alt-cost {
  display: flex; justify-content: space-between; align-items: baseline; gap: 8px;
  white-space: nowrap; font-variant-numeric: tabular-nums;
}
.effort { font-variant-numeric: tabular-nums; }

.alt-rank { font-weight: 700; color: var(--muted); }
.alt-main { display: grid; gap: 1px; min-width: 0; }
.alt-style { font-size: 0.75rem; color: var(--muted); }
.alt-tabs { display: flex; flex-wrap: wrap; gap: 2px 14px; font-family: ui-monospace, "Cascadia Mono", Consolas, monospace; letter-spacing: 0.04em; }
.alt-tabs .diff { color: var(--accent); font-weight: 700; }

/* ---- Progression page: arrangement --------------------------------------- */
#arrangement { margin: 32px 0 28px; }
#arrangement .alts { margin: 10px 0 0; }
#arrangement > .hint { margin-top: 10px; }
.sequence { display: flex; flex-wrap: wrap; align-items: stretch; gap: 12px 4px; margin-top: 14px; }
.sequence .voicing { width: 150px; justify-content: flex-start; }
.sequence .move { align-self: center; }
.step-name { font-weight: 700; font-size: 1.1rem; }
.step-name small, .sounds { font-weight: 400; font-size: 0.75rem; color: var(--muted); }
.move { display: flex; flex-direction: column; align-items: center; width: 40px; color: var(--muted); font-size: 1.1rem; line-height: 1.2; }
.move small { font-size: 0.7rem; }
.move.stay, .move.slide { color: var(--easy); }

/* ---- Progression page: scales -------------------------------------------- */
#scales { margin: 8px 0 32px; }
#scales h3 { font-size: 1rem; margin: 22px 0 8px; }
#scales h3 small { font-weight: 400; color: var(--muted); }
.scale-list { margin-top: 10px; }
.scale-row { line-height: 1.3; }
.scale-main small { color: var(--muted); font-weight: 400; }
.scale-notes { font-size: 0.8rem; }
.per-chord { list-style: none; margin: 0; padding: 0; display: grid; gap: 4px; }
.per-chord li {
  display: grid; grid-template-columns: 5.5em minmax(0, 1fr); gap: 10px; align-items: baseline;
  padding: 6px 10px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); font-size: 0.88rem;
}
.per-chord li.misfit { border-color: var(--medium); }
.pc-chord { font-weight: 700; }
.watch { color: var(--medium); font-weight: 600; text-decoration: underline dotted; cursor: help; }
.fb-head { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 8px 16px; margin: 22px 0 8px; }
.fb-head h3 { margin: 0 !important; }
.fb-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); padding: 8px 6px 2px; }
.fretboard { display: block; width: 100%; min-width: 720px; height: auto; }
.fb-string { stroke: var(--muted); stroke-width: 1; }
.fb-fret { stroke: var(--line); stroke-width: 1.5; }
.fb-nut { stroke: var(--text); stroke-width: 4; }
.fb-marker { fill: var(--line); }
.fb-num { fill: var(--muted); font-size: 11px; }
.fb-pos { fill: var(--accent); opacity: 0.12; }
.fb-note circle { fill: var(--surface); stroke: var(--text); stroke-width: 1.2; }
.fb-note text { fill: var(--text); font-size: 9.5px; font-weight: 600; }
.fb-note.root circle { fill: var(--accent); stroke: var(--accent); }
.fb-note.root text { fill: var(--accent-contrast); }
.fb-note.dim { opacity: 0.3; }

/* ---- Scoring legend ------------------------------------------------------ */
.legend { font-size: 0.85rem; color: var(--muted); }
.legend summary { cursor: pointer; color: var(--text); }
.legend p { margin: 8px 0; max-width: 75ch; }
.legend table { border-collapse: collapse; margin: 4px 0; }
.legend td { padding: 3px 14px 3px 0; vertical-align: top; }
.legend td:first-child { width: 8.5em; }
.legend td.num { font-variant-numeric: tabular-nums; white-space: nowrap; color: var(--text); }
#stats { margin: 12px 0 0; }

/* ---- Small screens ------------------------------------------------------- */
@media (max-width: 560px) {
  :root { --score-col: 9.5em; --label-col: 2.75rem; }
  .option { grid-template-columns: 5em minmax(0, 1fr) var(--score-col); }
  .option.infeasible .opt-score { grid-column: 2 / -1; justify-content: flex-start; font-size: 0.8rem; white-space: normal; }
  .alt { grid-template-columns: 1.6em minmax(0, 1fr); }
  .alt-cost { grid-column: 2; justify-content: flex-start; gap: 12px; }
  .badge { font-size: 0.68rem; letter-spacing: 0.03em; }
  .sequence .voicing { width: calc(50% - 24px); }
  .move { width: 32px; }
  /* Keep the title, logo and page links on one row on a phone. */
  header { column-gap: 8px; }
  nav a { padding: 4px 6px; }
}