:root {
  --bg: #f6f5f2;
  --panel: #ffffff;
  --ink: #1d1f24;
  --muted: #6b6f78;
  --line: #dedbd4;
  --accent: #2f5bd3;
  --accent-ink: #ffffff;
  --corner: #e9a23b;
  --corner-stroke: #9c6517;
  --edge: #5b7fbf;
  --edge-stroke: #2e4a7d;
  --half: rgba(47, 91, 211, 0.08);
  --slice: #c2392b;
  --ghost: #b9b5ac;
  --ok: #1f8a4c;
  --warn: #b5541c;
  --radius: 14px;
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #15171c;
    --panel: #1e2128;
    --ink: #e8e8ea;
    --muted: #9a9ea8;
    --line: #2f333c;
    --accent: #7b9cff;
    --accent-ink: #10131a;
    --corner: #e9a23b;
    --corner-stroke: #f5c77e;
    --edge: #6d8fcf;
    --edge-stroke: #b5c8ef;
    --half: rgba(123, 156, 255, 0.1);
    --slice: #ff6b5b;
    --ghost: #4a4f5a;
    --ok: #4cc584;
    --warn: #f08a4b;
    color-scheme: dark;
  }
}

:root[data-theme="dark"] {
  --bg: #15171c;
  --panel: #1e2128;
  --ink: #e8e8ea;
  --muted: #9a9ea8;
  --line: #2f333c;
  --accent: #7b9cff;
  --accent-ink: #10131a;
  --corner: #e9a23b;
  --corner-stroke: #f5c77e;
  --edge: #6d8fcf;
  --edge-stroke: #b5c8ef;
  --half: rgba(123, 156, 255, 0.1);
  --slice: #ff6b5b;
  --ghost: #4a4f5a;
  --ok: #4cc584;
  --warn: #f08a4b;
  color-scheme: dark;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 15px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

.top, main { max-width: 980px; margin: 0 auto; padding: 0 16px; }
.top { padding-top: 28px; padding-bottom: 8px; }
.top h1 { margin: 0; font-size: 26px; letter-spacing: -0.01em; }
.top h1 span { color: var(--muted); font-weight: 500; }
.top p { margin: 6px 0 0; color: var(--muted); max-width: 640px; }

main { display: grid; gap: 16px; padding-bottom: 40px; }

.panel {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
  min-width: 0;
}
.panel h2 { margin: 0 0 12px; font-size: 17px; }
.panel-head { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 10px; margin-bottom: 8px; }
.panel-head h2 { margin: 0; }

button {
  font: inherit;
  color: var(--ink);
  background: transparent;
  border: 1px solid var(--line);
  border-radius: 9px;
  padding: 6px 12px;
  cursor: pointer;
}
button:hover { border-color: var(--muted); }
button:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
button.primary { background: var(--accent); color: var(--accent-ink); border-color: var(--accent); }

.seg { display: inline-flex; align-items: center; gap: 4px; flex-wrap: wrap; }
.seg-label { color: var(--muted); margin-right: 4px; }
.seg button.on { background: var(--ink); color: var(--panel); border-color: var(--ink); }
.sw { display: inline-block; width: 10px; height: 10px; border-radius: 2px; margin-right: 6px; vertical-align: -1px; }
.sw.corner { background: var(--corner); }
.sw.edge { background: var(--edge); }

.faces { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; }
@media (max-width: 620px) { .faces { grid-template-columns: 1fr; } }

.face { margin: 0; display: flex; flex-direction: column; align-items: center; }
.face figcaption { text-align: center; }
.face figcaption small { display: block; color: var(--muted); }
.layer-svg { width: 100%; max-width: 320px; height: auto; touch-action: manipulation; }
.face .layer-svg { cursor: pointer; }
.face-tools { display: flex; gap: 6px; }
.face-tools button { min-width: 40px; }

.options, .actions { display: flex; flex-wrap: wrap; align-items: center; gap: 10px 18px; margin-top: 16px; }
.actions { gap: 8px; }
.check { display: inline-flex; align-items: center; gap: 6px; cursor: pointer; }

.status { margin: 14px 0 0; color: var(--muted); }
.status.bad { color: var(--warn); }
.status.good { color: var(--ok); }

/* Pièces */
.piece.corner { fill: var(--corner); stroke: var(--corner-stroke); }
.piece.edge { fill: var(--edge); stroke: var(--edge-stroke); }
.piece { stroke-width: 2; stroke-linejoin: round; }
.ghost { fill: none; stroke: var(--ghost); stroke-width: 1.5; stroke-dasharray: 4 4; }
.half { fill: var(--half); }
.slice-line { stroke: var(--slice); stroke-width: 3; stroke-linecap: round; }
.front-label { fill: var(--muted); font-size: 15px; letter-spacing: 0.08em; text-anchor: middle; }

/* Résultat */
.empty { color: var(--muted); margin: 0; }
.sequence {
  font: 600 clamp(18px, 4vw, 26px)/1.35 ui-monospace, "Cascadia Mono", Consolas, monospace;
  overflow-wrap: anywhere;
  margin: 0;
}
.meta { color: var(--muted); margin: 4px 0 0; }
.meta .ok { color: var(--ok); }
.meta .warn { color: var(--warn); }

.alts { display: flex; flex-wrap: wrap; gap: 6px; margin: 14px 0 0; padding: 0; list-style: none; }
.alts button { font: 13px ui-monospace, Consolas, monospace; }
.alts button.on { border-color: var(--accent); color: var(--accent); }

.steps {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(190px, 1fr));
  gap: 10px;
  margin-top: 18px;
}
.step { border: 1px solid var(--line); border-radius: 10px; padding: 10px; text-align: center; }
.step h3 { margin: 0 0 6px; font: 600 14px ui-monospace, Consolas, monospace; }
.step h3 small { display: block; font: 12px system-ui, sans-serif; color: var(--muted); }
.step .pair { display: grid; grid-template-columns: 1fr 1fr; gap: 4px; }
.step .pair svg { width: 100%; height: auto; }
.step.done { border-color: var(--ok); }

.reveal { margin-top: 4px; }

.help summary { cursor: pointer; font-weight: 600; }
.help ul { margin: 12px 0 0; padding-left: 20px; color: var(--muted); }
.help li { margin: 4px 0; }
code { font-family: ui-monospace, Consolas, monospace; color: var(--ink); }

/* Navigation */
.nav { display: flex; gap: 4px; margin-bottom: 14px; flex-wrap: wrap; }
.nav a {
  color: var(--muted); text-decoration: none; padding: 5px 12px;
  border: 1px solid var(--line); border-radius: 999px; font-size: 14px;
}
.nav a[aria-current="page"] { color: var(--ink); border-color: var(--ink); }
.nav a:hover { color: var(--ink); }

/* Glisser-déposer */
.palette { display: inline-flex; align-items: center; gap: 4px; }
.chip { display: inline-flex; align-items: center; gap: 6px; cursor: grab; touch-action: none; user-select: none; }
.chip svg { width: 16px; height: 18px; }
.chip .piece { stroke-width: 6; }
.layer-svg { touch-action: none; user-select: none; }
.drag-ghost {
  position: fixed; left: 0; top: 0; width: 34px; height: 38px; margin: -19px 0 0 -17px;
  pointer-events: none; opacity: 0; z-index: 10;
}
.drag-ghost.on { opacity: 0.9; }
.drag-ghost svg { width: 100%; height: 100%; overflow: visible; }
.drag-ghost .piece { stroke-width: 5; }
body.dragging, body.dragging * { cursor: grabbing !important; }
.preview { fill: var(--accent); fill-opacity: 0.35; stroke: var(--accent); stroke-width: 3; }
.hint { color: var(--muted); font-size: 13px; margin: 12px 0 0; }

/* Pièces en couleur (page Formules) */
:root {
  --st-U: #f4f4f2; --st-D: #f2c925; --st-F: #2e9e4f; --st-R: #d23b3b; --st-B: #2f68d0; --st-L: #f08a24;
  --st-stroke: #1d1f24;
}
.piece.st-U, .sticker.st-U { fill: var(--st-U); }
.piece.st-D, .sticker.st-D { fill: var(--st-D); }
.sticker.st-F { fill: var(--st-F); }
.sticker.st-R { fill: var(--st-R); }
.sticker.st-B { fill: var(--st-B); }
.sticker.st-L { fill: var(--st-L); }
.piece.st-U, .piece.st-D, .sticker { stroke: var(--st-stroke); stroke-width: 2.5; stroke-linejoin: round; }
.dim { opacity: 0.25; }

/* Page Formules */
.tabs { display: flex; gap: 4px; }
.tabs button.on { background: var(--ink); color: var(--panel); border-color: var(--ink); }
.formula-card { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 20px; }
@media (max-width: 760px) { .formula-card { grid-template-columns: 1fr; } }
.formula-card + .formula-card { margin-top: 0; }
.name-input {
  font: 600 18px system-ui, sans-serif; color: var(--ink); background: transparent;
  border: 1px solid transparent; border-radius: 8px; padding: 2px 6px; margin-left: -7px; width: 100%;
}
.name-input:hover, .name-input:focus { border-color: var(--line); outline: none; }
.effect { margin: 6px 0 0; }
.effect strong { font-family: ui-monospace, Consolas, monospace; }
.alg-input, .note-input, .answer {
  width: 100%; font: 15px/1.5 ui-monospace, Consolas, monospace; color: var(--ink);
  background: var(--bg); border: 1px solid var(--line); border-radius: 9px; padding: 8px 10px; resize: vertical;
}
.note-input { font-family: system-ui, sans-serif; }
.field-label { display: block; color: var(--muted); font-size: 13px; margin: 12px 0 4px; }
.error { color: var(--warn); font-size: 13px; margin: 4px 0 0; }
.pair { display: grid; grid-template-columns: 1fr 1fr; gap: 6px; }
.pair svg { width: 100%; height: auto; }
.tokens { display: flex; flex-wrap: wrap; gap: 2px 4px; font: 15px ui-monospace, Consolas, monospace; margin: 4px 0 0; }
.tokens button { padding: 1px 4px; border: 1px solid transparent; border-radius: 6px; font: inherit; }
.tokens button.cur { background: var(--accent); color: var(--accent-ink); }
.tokens button.past { color: var(--muted); }
.tokens .sep { width: 8px; }
.player { display: flex; flex-wrap: wrap; align-items: center; gap: 6px; margin-top: 8px; }
.player .pos { color: var(--muted); font-size: 13px; margin-left: 4px; }
.card-actions { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 12px; }
button.danger { color: var(--warn); }

/* Entraînement */
.boxes { display: flex; flex-wrap: wrap; gap: 8px; margin: 0 0 14px; padding: 0; list-style: none; }
.boxes li { border: 1px solid var(--line); border-radius: 10px; padding: 6px 10px; font-size: 13px; }
.boxes .lvl { display: inline-flex; gap: 2px; margin-left: 6px; vertical-align: -1px; }
.boxes .lvl i { width: 8px; height: 10px; border-radius: 2px; background: var(--line); }
.boxes .lvl i.on { background: var(--ok); }
.trainer { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.2fr); gap: 20px; }
@media (max-width: 760px) { .trainer { grid-template-columns: 1fr; } }
.trainer h3 { margin: 0 0 6px; }
.grade { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 12px; }
.feedback { margin: 10px 0 0; font: 15px/1.6 ui-monospace, Consolas, monospace; overflow-wrap: anywhere; }
.feedback .good { color: var(--ok); }
.feedback .bad { color: var(--warn); text-decoration: underline; }
.feedback .rest { color: var(--muted); }
.given { font: 15px ui-monospace, Consolas, monospace; color: var(--muted); margin: 8px 0 0; overflow-wrap: anywhere; }
[hidden] { display: none !important; }
.stack { display: grid; gap: 16px; }
select { font: inherit; color: var(--ink); background: var(--panel); border: 1px solid var(--line); border-radius: 8px; padding: 3px 6px; }

/* Carte de progression BTC */
.map { display: grid; gap: 8px; }
.map-row { display: grid; grid-template-columns: 140px minmax(0, 1fr); gap: 10px; align-items: start; }
@media (max-width: 560px) { .map-row { grid-template-columns: 1fr; gap: 4px; } }
.cells { display: flex; flex-wrap: wrap; gap: 3px; }
.cell { width: 14px; height: 14px; padding: 0; border: 0; border-radius: 3px; display: inline-block; }
button.cell:hover { outline: 2px solid var(--ink); outline-offset: 1px; }
.cell.l0 { background: var(--line); }
.cell.l1 { background: var(--warn); }
.cell.l2 { background: var(--ok); opacity: 0.35; }
.cell.l3 { background: var(--ok); opacity: 0.55; }
.cell.l4 { background: var(--ok); opacity: 0.8; }
.cell.l5 { background: var(--ok); }
.legend { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 12px; color: var(--muted); font-size: 13px; }
.legend .cell { width: 11px; height: 11px; margin-right: 5px; vertical-align: -1px; }
#timer { font-family: ui-monospace, Consolas, monospace; }

/* Fiche formule : formule en grand */
:root { --x: #2f5bd3; --y: #b5541c; }
@media (prefers-color-scheme: dark) { :root:not([data-theme="light"]) { --x: #8fb0ff; --y: #f3a46b; } }
:root[data-theme="dark"] { --x: #8fb0ff; --y: #f3a46b; }
.formula-head { display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 4px 20px; align-items: start; }
@media (max-width: 760px) { .formula-head { grid-template-columns: 1fr; } }
.formula-head .effect { margin: 4px 0 0; text-align: right; }
.formula-head .meta { margin: 0; text-align: right; }
@media (max-width: 760px) { .formula-head .effect, .formula-head .meta { text-align: left; } }
.formula-big {
  display: flex; flex-wrap: wrap; align-items: center; gap: 6px 2px;
  margin: 14px 0 0; padding: 16px 14px; border-radius: 12px; background: var(--bg); border: 1px solid var(--line);
  font: 600 clamp(19px, 3.2vw, 27px)/1.2 ui-monospace, "Cascadia Mono", Consolas, monospace;
}
.formula-big button { font: inherit; border: 1px solid transparent; border-radius: 8px; padding: 3px 5px; background: transparent; }
.formula-big .rot { background: var(--panel); border-color: var(--line); }
.formula-big .slash { color: var(--slice); padding: 3px 4px; font-weight: 800; }
.formula-big .p { color: var(--muted); font-weight: 400; }
.x { color: var(--x); }
.y { color: var(--y); }
.formula-big .zero { color: var(--muted); font-weight: 400; }
.formula-big button.past { opacity: 0.45; }
.formula-big button.cur { border-color: var(--accent); box-shadow: 0 0 0 2px var(--accent); opacity: 1; }
.formula-legend { margin: 6px 0 0; font-size: 13px; color: var(--muted); }
.formula-legend .x, .formula-legend .y { font-weight: 600; }
.formula-body { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 20px; margin-top: 8px; }
@media (max-width: 760px) { .formula-body { grid-template-columns: 1fr; } }
.edit { margin-top: 12px; }
.edit summary { cursor: pointer; color: var(--muted); font-size: 14px; margin-bottom: 8px; }

/* Vue 3D */
.stage3d { border-radius: 12px; background: var(--bg); border: 1px solid var(--line); overflow: hidden; }
canvas.view3d { display: block; width: 100%; cursor: grab; touch-action: none; }
canvas.view3d:active { cursor: grabbing; }
.views3d { display: flex; flex-wrap: wrap; align-items: center; gap: 6px; margin-top: 8px; }
.views3d button { font-size: 13px; padding: 4px 10px; }
.player3d .player select { margin-left: 4px; }
.anim3d { max-width: 520px; margin: 18px 0 0; }
.right-head { display: flex; align-items: center; justify-content: space-between; gap: 10px; margin: 12px 0 4px; }
.right-head .field-label { margin: 0; }
.view-toggle button { padding: 3px 10px; font-size: 13px; }

/* Pastilles : variante compacte */
.formula-big.small { font-size: 15px; padding: 8px 10px; margin-top: 8px; }

/* Boutons principaux larges (pratique au pouce) */
button.big { padding: 10px 18px; font-size: 16px; border-radius: 11px; }
.next-move { display: block; width: 100%; margin: 10px 0 2px; font: 600 18px ui-monospace, Consolas, monospace; }
.timer { float: right; margin-top: -34px; font-family: ui-monospace, Consolas, monospace; }
.card-sub { margin: -6px 0 12px; }
.stage3d.still { margin-top: 10px; }
.trainer.guided { grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr); }
.trainer.guided .pair { max-width: 360px; }

/* Réglages repliables */
.settings summary { cursor: pointer; font-weight: 600; font-size: 17px; }
.settings .options { margin-top: 14px; }

/* Familles */
.map-row.fam { grid-template-columns: 200px minmax(0, 1fr); align-items: center; }
.map-row.fam .check { gap: 8px; }
.map-row.fam .check span { display: flex; flex-direction: column; line-height: 1.2; }
.map-row.fam small { color: var(--muted); font-size: 12px; }
svg.thumb { width: 38px; height: 38px; flex: none; }
svg.thumb .half, svg.thumb .slice-line { display: none; }
@media (max-width: 560px) { .map-row.fam { grid-template-columns: 1fr; } }

/* Statistiques */
.days { display: flex; gap: 6px; list-style: none; padding: 0; margin: 8px 0 14px; flex-wrap: wrap; }
.days li { display: flex; flex-direction: column; align-items: center; min-width: 40px; padding: 4px 6px; border: 1px solid var(--line); border-radius: 8px; }
.table-wrap { overflow-x: auto; }
.stats-table { border-collapse: collapse; width: 100%; font-size: 14px; }
.stats-table th, .stats-table td { text-align: left; padding: 6px 10px 6px 0; border-bottom: 1px solid var(--line); white-space: nowrap; }
.stats-table th { color: var(--muted); font-weight: 500; }
.stats-table td + td, .stats-table th + th { text-align: right; }
.sub-title { font-size: 15px; margin: 18px 0 8px; }
.traps { display: grid; grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); gap: 8px; }
.trap { display: flex; flex-direction: column; gap: 4px; padding: 8px; font-size: 13px; text-align: center; }

/* Pavé de saisie */
.pad-wrap { margin-top: 8px; }
.pad-toggle { font-size: 13px; padding: 4px 10px; }
.pad { margin-top: 8px; display: grid; gap: 8px; }
.pad-row { display: grid; grid-template-columns: 44px minmax(0, 1fr); gap: 6px; align-items: center; }
.pad-label { font-weight: 600; font-size: 13px; }
.pad-grid { display: grid; grid-template-columns: repeat(6, minmax(0, 1fr)); gap: 4px; }
.pad-key { min-height: 40px; padding: 4px 0; font: 600 16px ui-monospace, Consolas, monospace; touch-action: manipulation; }
.pad-key.on { background: var(--ink); color: var(--panel); border-color: var(--ink); }
.pad-actions { display: grid; grid-template-columns: 1.3fr 1.3fr 1fr; gap: 6px; }
.pad-actions .pad-key { min-height: 46px; }
.slash-key { font-size: 22px; }
.pad-preview .p { color: var(--muted); }

/* --- Mobile ------------------------------------------------------------------ */
input, select, textarea { font-size: 16px; } /* évite le zoom automatique sur iOS */
.alg-input, .note-input, .answer { font-size: 16px; }
button { touch-action: manipulation; }
canvas.view3d { touch-action: pan-y; } /* défilement vertical conservé, glisser horizontal = rotation */

@media (pointer: coarse) {
  button, .nav a, select { min-height: 40px; }
  .cell { width: 20px; height: 20px; }
  .formula-big button { min-height: 0; }
  .chip { min-height: 40px; }
}

@media (max-width: 560px) {
  body { font-size: 15px; }
  .top { padding-top: 16px; }
  .top h1 { font-size: 22px; }
  .top p { font-size: 14px; }
  main { gap: 12px; }
  .panel { padding: 14px; border-radius: 12px; }
  .nav a { padding: 8px 12px; }
  .panel-head { gap: 8px; }
  .options { gap: 10px 14px; }
  .formula-big { font-size: 19px; padding: 10px; gap: 6px 1px; }
  .sequence { font-size: 20px; }
  .steps { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 8px; }
  .step { padding: 6px; }
  .player { gap: 4px; }
  .player button { padding: 6px 10px; }
  .timer { float: none; margin: 0 0 6px; display: block; }
  .grade { gap: 6px; }
  .grade button.big { flex: 1 1 0; }
  .layer-svg { max-width: 280px; }
  .actions button { flex: 1 1 auto; }
  .stats-table { font-size: 13px; }
}

body { padding-bottom: env(safe-area-inset-bottom); }
@media (max-width: 760px) { .trainer.guided { grid-template-columns: 1fr; } }