/* Swing Kid Gym. Layout: app shell (header + tabs), then a two-column instrument bench that
   stacks on narrow screens. Palette from the build itself: breadboard white-gray, ELEGOO board
   blue, kraft cardboard, a wooden spoon, twine; targets are pink. Display face: Archivo (wide),
   body: Atkinson Hyperlegible, readings: IBM Plex Mono. */
:root {
  --bg: #e9edf1;
  --panel: #fbfcfd;
  --panel-2: #f2f5f8;
  --ink: #11161c;
  --ink-2: #47515d;
  --ink-3: #6f7a87;
  --line: #d6dce3;
  --line-2: #c3cbd5;
  --pcb: #1f5fbf;
  --pcb-ink: #ffffff;
  --accent: #c2185b;
  --wood: #d9b07a;
  --wood-2: #9c7442;
  --string: #8a7a62;
  --kraft: #c89d6a;
  --kraft-2: #a97e4f;
  --kraft-3: #e2c49b;
  --good: #0a8f0a;
  --bad: #c83434;
  --warn: #b77800;
  --series-1: #2a78d6;
  --series-2: #eb6834;
  --div-neg: #2a78d6;
  --div-mid: #ecebe7;
  --div-pos: #d64545;
  --grid: #e1e5ea;
  --axis: #c3cbd5;
  --stage-top: #f6f8fa;
  --stage-bot: #e3e8ee;
  --font-display: "Archivo", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-body: "Atkinson Hyperlegible", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-mono: "IBM Plex Mono", ui-monospace, "SF Mono", Menlo, monospace;
  --radius: 10px;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0c1015; --panel: #141a21; --panel-2: #1b222b; --ink: #e8edf2; --ink-2: #b1bbc6; --ink-3: #808b98;
    --line: #27303a; --line-2: #36414d; --pcb: #4b8fe8; --pcb-ink: #08111d; --accent: #f06292; --wood: #c59b63; --wood-2: #7f5d35; --string: #b8a88e;
    --kraft: #b98f5f; --kraft-2: #8e6a43; --kraft-3: #d2b285; --good: #2fbf2f; --bad: #e46262; --warn: #e2a72b;
    --series-1: #3987e5; --series-2: #d95926; --div-neg: #3987e5; --div-mid: #383835; --div-pos: #e46262;
    --grid: #232a33; --axis: #36414d; --stage-top: #18202a; --stage-bot: #0f151c;
    color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --bg: #0c1015; --panel: #141a21; --panel-2: #1b222b; --ink: #e8edf2; --ink-2: #b1bbc6; --ink-3: #808b98;
  --line: #27303a; --line-2: #36414d; --pcb: #4b8fe8; --pcb-ink: #08111d; --accent: #f06292; --wood: #c59b63; --wood-2: #7f5d35; --string: #b8a88e;
  --kraft: #b98f5f; --kraft-2: #8e6a43; --kraft-3: #d2b285; --good: #2fbf2f; --bad: #e46262; --warn: #e2a72b;
  --series-1: #3987e5; --series-2: #d95926; --div-neg: #3987e5; --div-mid: #383835; --div-pos: #e46262;
  --grid: #232a33; --axis: #36414d; --stage-top: #18202a; --stage-bot: #0f151c;
  color-scheme: dark;
}

* { box-sizing: border-box; }
html, body { margin: 0; }
body {
  background: var(--bg);
  color: var(--ink);
  font: 15px/1.5 var(--font-body);
  padding-left: max(16px, env(safe-area-inset-left, 0px));
  padding-right: max(16px, env(safe-area-inset-right, 0px));
  padding-block: 0 48px;
}
[hidden] { display: none !important; }
button, input, select { font: inherit; color: inherit; }
:focus-visible { outline: 2px solid var(--pcb); outline-offset: 2px; }
code { font-family: var(--font-mono); font-size: 0.92em; background: var(--panel-2); padding: 0.1em 0.35em; border-radius: 4px; }

/* ---------------------------------------------------------------- header */
.top {
  position: sticky; top: env(safe-area-inset-top, 0px); z-index: 10;
  display: flex; align-items: center; gap: 24px; flex-wrap: wrap;
  padding-block: 14px; margin-bottom: 18px;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}
.brand { display: flex; align-items: baseline; gap: 10px; }
.wordmark { font: 800 22px/1 var(--font-display); font-stretch: 125%; letter-spacing: 0.06em; }
.brand-sub { font: 500 13px/1 var(--font-mono); color: var(--ink-3); letter-spacing: 0.12em; text-transform: uppercase; }
.tabs { display: flex; gap: 4px; background: var(--panel-2); padding: 4px; border-radius: 999px; border: 1px solid var(--line); }
.tab {
  border: 0; background: none; padding: 7px 16px; border-radius: 999px; cursor: pointer;
  font: 600 14px/1 var(--font-display); font-stretch: 110%; color: var(--ink-2);
}
.tab[aria-selected="true"] { background: var(--panel); color: var(--ink); box-shadow: 0 1px 2px rgba(0,0,0,0.12); }
.conn { margin-left: auto; display: flex; align-items: center; gap: 8px; font: 500 13px/1.2 var(--font-mono); color: var(--ink-2); }
.conn .dot { width: 9px; height: 9px; border-radius: 50%; background: var(--line-2); }
.conn[data-state="on"] .dot { background: var(--good); box-shadow: 0 0 0 3px color-mix(in srgb, var(--good) 25%, transparent); }
.conn[data-state="busy"] .dot { background: var(--warn); }

/* ---------------------------------------------------------------- layout */
main { max-width: 1440px; margin: 0 auto; }
.dream-grid, .robot-grid { display: grid; grid-template-columns: minmax(0, 1.65fr) minmax(0, 1fr); gap: 18px; align-items: start; }
.robot-grid { grid-template-columns: minmax(0, 1fr) minmax(0, 1.6fr); }
.col-main, .col-side { display: grid; gap: 18px; min-width: 0; }
@media (max-width: 1060px) { .dream-grid, .robot-grid { grid-template-columns: minmax(0, 1fr); } }

.card { background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius); padding: 18px 20px; min-width: 0; }
.card-head { display: flex; justify-content: space-between; align-items: flex-start; gap: 16px; flex-wrap: wrap; margin-bottom: 12px; }
.card-head.tight { align-items: baseline; margin-bottom: 8px; }
.eyebrow { margin: 0 0 4px; font: 600 12px/1.2 var(--font-mono); letter-spacing: 0.14em; text-transform: uppercase; color: var(--ink-3); }
.lede { margin: 0; color: var(--ink-2); max-width: 62ch; }
.meta { font: 500 12px/1.3 var(--font-mono); color: var(--ink-3); }
.caption { margin: 10px 0 0; font-size: 13.5px; color: var(--ink-3); max-width: 62ch; }
.hint { font-size: 13.5px; color: var(--ink-3); }
.status { margin: 8px 0 0; font: 500 13px/1.4 var(--font-mono); color: var(--ink-2); min-height: 1.4em; }
.row { display: flex; gap: 10px; align-items: center; margin-top: 12px; }
.row.wrap { flex-wrap: wrap; }

/* ---------------------------------------------------------------- controls */
.btn {
  border: 1px solid var(--line-2); background: var(--panel-2); color: var(--ink);
  padding: 8px 14px; border-radius: 8px; cursor: pointer; font: 600 14px/1.2 var(--font-display); font-stretch: 105%;
}
.btn:hover { border-color: var(--ink-3); }
.btn:disabled { opacity: 0.45; cursor: default; }
.btn.primary { background: var(--pcb); border-color: var(--pcb); color: var(--pcb-ink); }
.btn.primary:hover { filter: brightness(1.08); }
.btn.ghost { background: transparent; }
.btn.big { padding: 13px 20px; font-size: 17px; }
.btn.wide { width: 100%; margin-top: 14px; }
.seg { display: inline-flex; border: 1px solid var(--line-2); border-radius: 8px; overflow: hidden; }
.seg-btn { border: 0; background: transparent; padding: 7px 12px; cursor: pointer; font: 600 13px/1.2 var(--font-display); color: var(--ink-2); }
.seg-btn + .seg-btn { border-left: 1px solid var(--line-2); }
.seg-btn[aria-checked="true"] { background: var(--ink); color: var(--panel); }
.select-wrap { display: inline-flex; align-items: center; gap: 8px; font-size: 13.5px; color: var(--ink-2); }
select { background: var(--panel-2); border: 1px solid var(--line-2); border-radius: 8px; padding: 6px 8px; }
.toggle { display: grid; grid-template-columns: auto 1fr; gap: 12px; align-items: start; margin-top: 16px; cursor: pointer; font-size: 14px; color: var(--ink-2); }
.toggle input { position: absolute; opacity: 0; width: 1px; height: 1px; }
.toggle .track { grid-row: 1; width: 38px; height: 22px; border-radius: 999px; background: var(--line-2); position: relative; margin-top: 2px; transition: background 0.15s; }
.toggle .track::after { content: ""; position: absolute; top: 3px; left: 3px; width: 16px; height: 16px; border-radius: 50%; background: var(--panel); transition: transform 0.15s; box-shadow: 0 1px 2px rgba(0,0,0,0.25); }
.toggle input:checked + .track { background: var(--pcb); }
.toggle input:checked + .track::after { transform: translateX(16px); }
.toggle input:focus-visible + .track { outline: 2px solid var(--pcb); outline-offset: 2px; }
.toggle strong { color: var(--ink); }
.slider { display: inline-flex; align-items: center; gap: 10px; font-size: 13.5px; color: var(--ink-2); }
.slider input { width: 180px; accent-color: var(--accent); }
.slider output { font: 500 13px/1 var(--font-mono); min-width: 4.5ch; }
progress { width: 100%; height: 8px; margin-top: 12px; accent-color: var(--pcb); }

/* ---------------------------------------------------------------- stage */
.stage-card { padding-bottom: 14px; }
.stage-wrap { position: relative; border-radius: 8px; overflow: hidden; border: 1px solid var(--line); }
.stage { display: block; width: 100%; aspect-ratio: 16 / 8; cursor: crosshair; touch-action: none; }
.chips { position: absolute; left: 10px; top: 10px; display: flex; flex-wrap: wrap; gap: 6px; max-width: calc(100% - 20px); pointer-events: none; }
.chip { font: 500 11.5px/1 var(--font-mono); padding: 5px 8px; border-radius: 999px; background: color-mix(in srgb, var(--panel) 86%, transparent); border: 1px solid var(--line); color: var(--ink-2); }
.you-hint { position: absolute; bottom: 10px; left: 50%; transform: translateX(-50%); font-size: 13px; background: var(--ink); color: var(--panel); padding: 6px 12px; border-radius: 999px; white-space: nowrap; }
.stage-foot { display: flex; justify-content: space-between; align-items: center; gap: 14px; flex-wrap: wrap; margin-top: 12px; }
.stage-actions { display: flex; gap: 12px; align-items: center; flex-wrap: wrap; }
.thumbs { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 8px; }
.thumbs canvas { width: 100%; aspect-ratio: 2 / 1; display: block; border-radius: 6px; background: var(--panel-2); border: 1px solid var(--line); }
@media (max-width: 560px) { .thumbs { grid-template-columns: repeat(2, minmax(0, 1fr)); } }

/* ---------------------------------------------------------------- training card */
.train-top { display: flex; gap: 10px; }
.train-top .big { flex: 1; }
.stats { display: grid; grid-template-columns: 1fr 1fr; gap: 14px 18px; margin: 18px 0 0; }
.stats > div { display: grid; gap: 2px; }
.stats dt { font: 600 11.5px/1.2 var(--font-mono); letter-spacing: 0.12em; text-transform: uppercase; color: var(--ink-3); }
.stats dd { margin: 0; font: 700 26px/1.1 var(--font-display); font-stretch: 112%; }
.stats .sub { font-size: 12.5px; color: var(--ink-3); }

/* ---------------------------------------------------------------- charts */
.chart-box { position: relative; }
.chart { display: block; width: 100%; height: 210px; }
.chart-box.square .chart { height: auto; aspect-ratio: 4 / 3; cursor: crosshair; }
.chart-box.short .chart { height: 170px; margin-top: 12px; }
.tip {
  position: absolute; pointer-events: none; z-index: 2; min-width: 120px; max-width: 260px;
  background: var(--panel); border: 1px solid var(--line-2); border-radius: 8px; padding: 8px 10px;
  box-shadow: 0 4px 16px rgba(0,0,0,0.14); font-size: 12.5px; color: var(--ink-2);
}
.tip strong { display: block; font: 600 15px/1.3 var(--font-display); color: var(--ink); }
.tip .k-line { display: inline-block; width: 14px; height: 2px; border-radius: 1px; vertical-align: middle; margin-right: 6px; }
.legend-ramp { display: flex; align-items: center; gap: 10px; margin-top: 10px; font-size: 12.5px; color: var(--ink-3); }
.legend-ramp .ramp { flex: 1; height: 8px; border-radius: 4px; background: linear-gradient(90deg, var(--div-neg), var(--div-mid), var(--div-pos)); }
.net { display: block; width: 100%; aspect-ratio: 5 / 3; }

/* ---------------------------------------------------------------- exam */
.exam-head { display: flex; justify-content: space-between; gap: 20px; flex-wrap: wrap; align-items: flex-end; margin-bottom: 18px; }
.exam-pick { display: flex; gap: 12px; align-items: center; flex-wrap: wrap; }
.exam-body { display: grid; grid-template-columns: minmax(0, 1.8fr) minmax(0, 1fr); gap: 18px; align-items: start; }
@media (max-width: 1060px) { .exam-body { grid-template-columns: minmax(0, 1fr); } }
.tiles { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 12px; margin-bottom: 16px; }
@media (max-width: 700px) { .tiles { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
.tile { display: grid; gap: 4px; padding: 12px 14px; background: var(--panel-2); border-radius: 8px; }
.t-label { font: 600 11.5px/1.2 var(--font-mono); letter-spacing: 0.12em; text-transform: uppercase; color: var(--ink-3); }
.t-val { font: 700 30px/1.1 var(--font-display); font-stretch: 112%; }
.t-sub { font-size: 12.5px; color: var(--ink-3); }
.worlds { display: grid; grid-template-columns: repeat(8, minmax(0, 1fr)); gap: 6px; }
@media (max-width: 900px) { .worlds { grid-template-columns: repeat(4, minmax(0, 1fr)); } }
.world { position: relative; border-radius: 6px; background: var(--panel-2); border: 1px solid var(--line); overflow: hidden; }
.world canvas { display: block; width: 100%; aspect-ratio: 3 / 2; }
.world .badge { position: absolute; top: 4px; right: 4px; font: 600 10.5px/1 var(--font-mono); padding: 3px 5px; border-radius: 4px; background: var(--panel); border: 1px solid var(--line); }
.world .badge.pass { color: var(--good); }
.world .badge.fail { color: var(--bad); }
.eeprom { display: block; width: 100%; aspect-ratio: 1 / 1; max-width: 360px; margin: 6px auto 10px; }
.key { display: flex; gap: 14px; flex-wrap: wrap; font-size: 12.5px; color: var(--ink-2); }
.k { display: inline-block; width: 10px; height: 10px; border-radius: 2px; margin-right: 6px; vertical-align: -1px; }
.k-set { background: var(--kraft); } .k-brain { background: var(--pcb); } .k-free { background: var(--line); }

/* ---------------------------------------------------------------- robot */
.no-serial { margin-bottom: 18px; border-color: var(--warn); }
.no-serial p { margin: 6px 0 0; color: var(--ink-2); max-width: 75ch; }
.checks { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; margin-top: 8px; }
.check { display: grid; gap: 2px; padding: 10px 12px; background: var(--panel-2); border-radius: 8px; }
.c-name { font: 600 11.5px/1.2 var(--font-mono); letter-spacing: 0.12em; text-transform: uppercase; color: var(--ink-3); }
.c-val { font: 600 18px/1.25 var(--font-display); }
.c-hint { font-size: 12px; color: var(--ink-3); }
.cal-steps { margin: 10px 0 0; padding-left: 20px; font-size: 13.5px; color: var(--ink-3); display: grid; gap: 4px; }
.cal-steps li[data-state="active"] { color: var(--ink); font-weight: 700; }
.cal-steps li[data-state="done"] { color: var(--good); }
.cal-steps li[data-state="fail"] { color: var(--bad); }
.cmd { flex: 1; min-width: 0; background: var(--panel-2); border: 1px solid var(--line-2); border-radius: 8px; padding: 7px 10px; font: 13px/1.2 var(--font-mono); }
.log-card summary { cursor: pointer; font: 600 12px/1.2 var(--font-mono); letter-spacing: 0.14em; text-transform: uppercase; color: var(--ink-3); }
.log { max-height: 260px; overflow: auto; margin: 10px 0 0; font: 12px/1.45 var(--font-mono); color: var(--ink-2); background: var(--panel-2); padding: 10px; border-radius: 8px; white-space: pre-wrap; }

.toast { position: fixed; left: 50%; bottom: calc(18px + env(safe-area-inset-bottom, 0px)); transform: translateX(-50%); background: var(--ink); color: var(--panel); padding: 10px 16px; border-radius: 10px; font-size: 14px; z-index: 50; max-width: calc(100% - 32px); }

@media (prefers-reduced-motion: reduce) { * { transition: none !important; } }

@media (max-width: 640px) {
  .stage { aspect-ratio: 4 / 3; }
  .chips { position: static; max-width: none; padding: 8px 10px 10px; background: var(--panel-2); border-top: 1px solid var(--line); }
  .you-hint { white-space: normal; text-align: center; width: calc(100% - 20px); }
}

/* ---------------------------------------------------------------- Swing Kid additions */
.slider.block { display: grid; grid-template-columns: 1fr auto; gap: 6px 10px; margin-top: 18px; color: var(--ink); font-weight: 700; font-size: 14px; }
.slider.block input { grid-column: 1; width: 100%; }
.slider.block output { grid-column: 2; grid-row: 2; }
.caption.tight { margin-top: 6px; }
.mine { margin-top: 6px; }
.mine .toggle { margin-top: 10px; }
.toggle input:disabled + .track { opacity: 0.5; }
.ptable { width: 100%; border-collapse: collapse; margin: 6px 0 16px; font-size: 14px; }
.ptable th, .ptable td { text-align: left; padding: 7px 10px; border-bottom: 1px solid var(--line); }
.ptable thead th { font: 600 11.5px/1.2 var(--font-mono); letter-spacing: 0.1em; text-transform: uppercase; color: var(--ink-3); }
.ptable td { font: 500 14px/1.3 var(--font-mono); color: var(--ink); }
.ptable tbody th { font-weight: 400; color: var(--ink-2); }
.ptable td.win { font-weight: 700; }
.ptable.fit { margin-top: 12px; }
.k.k-s1 { background: var(--series-1); } .k.k-s2 { background: var(--series-2); } .k.k-tgt { background: var(--accent); } .k.k-bad { background: var(--bad); }
.k.k-line { height: 3px; width: 14px; border-radius: 2px; vertical-align: 3px; }
.exam-key { margin: 0 0 10px; }
.cal-steps .r { display: block; font: 500 12.5px/1.4 var(--font-mono); color: var(--ink-2); font-weight: 400; }
.cal-steps li[data-state="active"] .r, .cal-steps li[data-state="done"] .r { color: var(--ink-2); }
.worlds { grid-template-columns: repeat(6, minmax(0, 1fr)); }
@media (max-width: 900px) { .worlds { grid-template-columns: repeat(3, minmax(0, 1fr)); } }
.world canvas { aspect-ratio: 2 / 1; }
.stage { aspect-ratio: 16 / 9; }
.world.failed { border-color: color-mix(in srgb, var(--bad) 55%, var(--line)); }