/* Extracted from the original single-file trainer. */
/* Layout: a revision desk. Topic rail on the left (chips on phones), one study card at a time on the right. */
:root {
  --bg: #f3f5f1;
  --surface: #ffffff;
  --ink: #17221d;
  --muted: #5a6760;
  --line: #d9dfd8;
  --accent: #1d6a50;
  --accent-soft: #e2efe8;
  --accent-ink: #ffffff;
  --good: #1f7a45;
  --good-soft: #e3f3e8;
  --bad: #b3322b;
  --bad-soft: #fbe9e7;
  --tip: #8a5a00;
  --tip-soft: #fbf1dc;
  --given: #edf1f6;
  --given-ink: #26405f;
  --chart-bg: #ffffff;
  --simple: #6b3fa0;
  --simple-soft: #f1ebf8;
  --display: "Bricolage Grotesque", "Segoe UI", system-ui, sans-serif;
  --body: "Source Sans 3", "Segoe UI", system-ui, sans-serif;
  --mono: "JetBrains Mono", ui-monospace, "SFMono-Regular", Menlo, monospace;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #111815; --surface: #19221e; --ink: #e6ece8; --muted: #9aa8a0; --line: #2c3833;
    --accent: #5cc49a; --accent-soft: #1f3a2f; --accent-ink: #0d1a14;
    --good: #6fd39a; --good-soft: #17372a; --bad: #f08a80; --bad-soft: #3d1f1c;
    --tip: #f0c46a; --tip-soft: #3a2f17; --given: #1d2a38; --given-ink: #b9d0ea; --chart-bg: #ffffff; --simple: #c7a6f0; --simple-soft: #2a2138;
    color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --bg: #111815; --surface: #19221e; --ink: #e6ece8; --muted: #9aa8a0; --line: #2c3833;
  --accent: #5cc49a; --accent-soft: #1f3a2f; --accent-ink: #0d1a14;
  --good: #6fd39a; --good-soft: #17372a; --bad: #f08a80; --bad-soft: #3d1f1c;
  --tip: #f0c46a; --tip-soft: #3a2f17; --given: #1d2a38; --given-ink: #b9d0ea; --chart-bg: #ffffff; --simple: #c7a6f0; --simple-soft: #2a2138;
  color-scheme: dark;
}
* { box-sizing: border-box; }
body { background: var(--bg); color: var(--ink); font-family: var(--body); font-size: 17px; line-height: 1.55; }
.wrap { max-width: 1120px; margin: 0 auto; padding-block: 20px 48px; padding-left: max(16px, env(safe-area-inset-left, 0px)); padding-right: max(16px, env(safe-area-inset-right, 0px)); }
header.top { display: flex; flex-wrap: wrap; align-items: flex-end; justify-content: space-between; gap: 12px 24px; margin-bottom: 20px; }
.eyebrow { font-family: var(--mono); font-size: 12px; letter-spacing: .08em; text-transform: uppercase; color: var(--accent); }
h1 { font-family: var(--display); font-weight: 700; font-size: clamp(28px, 4vw, 38px); line-height: 1.1; margin: 4px 0 0; text-wrap: balance; }
.overall { min-width: 220px; flex: 0 1 300px; }
.overall .label { display: flex; flex-wrap: wrap; gap: 4px 12px; justify-content: space-between; font-size: 14px; color: var(--muted); font-variant-numeric: tabular-nums; }
.bar { height: 8px; border-radius: 99px; background: var(--line); overflow: hidden; margin-top: 6px; }
.bar > span { display: block; height: 100%; background: var(--accent); width: 0; transition: width .3s; }

.layout { display: grid; grid-template-columns: 270px minmax(0, 1fr); gap: 24px; align-items: start; }
nav.rail { position: sticky; top: calc(env(safe-area-inset-top, 0px) + 12px); display: flex; flex-direction: column; gap: 2px; max-height: calc(100vh - 24px - env(safe-area-inset-top, 0px)); overflow-y: auto; padding-right: 4px; }
nav.rail button { all: unset; box-sizing: border-box; cursor: pointer; display: grid; grid-template-columns: 28px 1fr auto; gap: 8px; align-items: center; padding: 8px 10px; border-radius: 8px; font-size: 15px; line-height: 1.3; color: var(--ink); }
nav.rail button:hover { background: var(--accent-soft); }
nav.rail button:focus-visible { outline: 2px solid var(--accent); outline-offset: 1px; }
nav.rail button[aria-current="true"] { background: var(--surface); box-shadow: inset 3px 0 0 var(--accent); font-weight: 600; }
.num { font-family: var(--mono); font-size: 12px; color: var(--muted); }
.score { font-family: var(--mono); font-size: 12px; color: var(--muted); font-variant-numeric: tabular-nums; }
.score.full { color: var(--good); }
.rail-select { display: none; }
.rail-group { font-family: var(--mono); font-size: 11px; letter-spacing: .07em; text-transform: uppercase; color: var(--accent); padding: 14px 10px 4px; line-height: 1.35; }
.rail-group:first-child { padding-top: 0; }

main.card { background: var(--surface); border: 1px solid var(--line); border-radius: 14px; padding: clamp(18px, 3vw, 32px); min-width: 0; }
.card-head { display: flex; flex-wrap: wrap; gap: 8px 16px; justify-content: space-between; align-items: baseline; margin-bottom: 8px; }
.where { font-family: var(--mono); font-size: 12px; letter-spacing: .06em; text-transform: uppercase; color: var(--muted); }
.qcount { font-family: var(--mono); font-size: 13px; color: var(--muted); font-variant-numeric: tabular-nums; }
h2 { font-family: var(--display); font-weight: 700; font-size: clamp(22px, 3vw, 28px); line-height: 1.2; margin: 0 0 14px; text-wrap: balance; }
h3 { font-family: var(--display); font-weight: 500; font-size: 19px; margin: 22px 0 8px; }
p { margin: 0 0 12px; max-width: 68ch; }
ol, ul { margin: 0 0 12px; padding-left: 22px; max-width: 68ch; }
li { margin-bottom: 6px; }
.calc { font-family: var(--mono); font-size: 14px; background: var(--bg); border: 1px solid var(--line); border-radius: 5px; padding: 1px 6px; white-space: normal; overflow-wrap: anywhere; -webkit-box-decoration-break: clone; box-decoration-break: clone; }
.box { border-radius: 10px; padding: 14px 16px; margin: 14px 0; }
.box > :last-child { margin-bottom: 0; }
.box .tag { font-family: var(--mono); font-size: 11.5px; letter-spacing: .08em; text-transform: uppercase; font-weight: 500; margin-bottom: 6px; }
.goal { background: var(--accent-soft); }
.goal .tag { color: var(--accent); }
.given { background: var(--given); color: var(--given-ink); }
.given .tag { color: var(--given-ink); }
.examq { border: 1px dashed var(--line); }
.examq .tag { color: var(--muted); }
.tipbox { background: var(--tip-soft); }
.tipbox .tag { color: var(--tip); }

.question { font-size: 19px; font-weight: 600; margin: 6px 0 14px; max-width: 68ch; }
.options { display: grid; gap: 10px; margin: 0 0 18px; }
.opt { all: unset; box-sizing: border-box; cursor: pointer; display: grid; grid-template-columns: 30px minmax(0, 1fr); gap: 10px; align-items: start; padding: 12px 14px; border: 1.5px solid var(--line); border-radius: 10px; background: var(--surface); line-height: 1.45; }
.opt:hover:not([disabled]) { border-color: var(--accent); }
.opt:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.opt .letter { font-family: var(--mono); font-size: 13px; width: 26px; height: 26px; border-radius: 50%; display: grid; place-items: center; border: 1.5px solid var(--line); color: var(--muted); }
.opt[aria-pressed="true"] { border-color: var(--accent); background: var(--accent-soft); }
.opt[aria-pressed="true"] .letter { background: var(--accent); border-color: var(--accent); color: var(--accent-ink); }
.opt.right { border-color: var(--good); background: var(--good-soft); }
.opt.right .letter { background: var(--good); border-color: var(--good); color: var(--accent-ink); }
.opt.wrong { border-color: var(--bad); background: var(--bad-soft); }
.opt.wrong .letter { background: var(--bad); border-color: var(--bad); color: var(--accent-ink); }
.opt[disabled] { cursor: default; }

.verdict { display: flex; gap: 10px; align-items: center; font-family: var(--display); font-weight: 700; font-size: 21px; margin: 4px 0 10px; }
.verdict.ok { color: var(--good); }
.verdict.no { color: var(--bad); }
.verdict .pill { font-family: var(--mono); font-size: 12px; font-weight: 500; padding: 3px 9px; border-radius: 99px; background: currentColor; }
.verdict .pill span { color: var(--surface); }
.explain { border-top: 1px solid var(--line); padding-top: 14px; margin-top: 6px; }
figure { margin: 16px 0; }
figure .chart { background: var(--chart-bg); border-radius: 10px; padding: 8px; border: 1px solid var(--line); overflow-x: auto; }
figure img { display: block; width: 100%; max-width: 640px; height: auto; margin: 0 auto; }
figure svg.inline { display: block; width: 100%; max-width: 560px; height: auto; margin: 0 auto; }
figcaption { font-size: 14px; color: var(--muted); margin-top: 6px; }

.actions { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 20px; }
.btn { all: unset; box-sizing: border-box; cursor: pointer; font-weight: 600; font-size: 16px; padding: 11px 18px; border-radius: 9px; background: var(--accent); color: var(--accent-ink); }
.btn:hover { filter: brightness(1.08); }
.btn:focus-visible { outline: 2px solid var(--ink); outline-offset: 2px; }
.btn[disabled] { opacity: .45; cursor: not-allowed; filter: none; }
.btn.ghost { background: transparent; color: var(--ink); border: 1.5px solid var(--line); }
.dots { display: flex; flex-wrap: wrap; gap: 6px; margin: 4px 0 16px; }
.dot { width: 22px; height: 6px; border-radius: 99px; background: var(--line); }
.dot.ok { background: var(--good); }
.dot.no { background: var(--bad); }
.dot.here { outline: 2px solid var(--accent); outline-offset: 1px; }
.result-big { font-family: var(--display); font-size: 48px; font-weight: 700; line-height: 1; color: var(--accent); font-variant-numeric: tabular-nums; }
.missed li { cursor: pointer; text-decoration: underline; text-underline-offset: 3px; }


.meaning { background: var(--good-soft); }
.meaning .tag { color: var(--good); }
ol.exsteps { padding-left: 24px; }
ol.exsteps > li { margin-bottom: 10px; padding-left: 4px; }
.dot.learn { background: var(--given); }
.dot.learn.seen { background: var(--given-ink); opacity: .55; }


.simple-wrap { margin: 16px 0 4px; }
.simple-btn { all: unset; box-sizing: border-box; cursor: pointer; display: inline-flex; align-items: center; gap: 10px; font-weight: 600; font-size: 16px; padding: 10px 16px; border-radius: 9px; border: 1.5px dashed var(--simple); color: var(--simple); background: transparent; }
.simple-btn:hover { background: var(--simple-soft); }
.simple-btn:focus-visible { outline: 2px solid var(--simple); outline-offset: 2px; }
.simple-icon { font-family: var(--mono); font-size: 18px; width: 22px; height: 22px; display: grid; place-items: center; border-radius: 50%; background: var(--simple); color: var(--surface); line-height: 1; }
.simple { background: var(--simple-soft); }
.simple .tag { color: var(--simple); }
.simple ol { padding-left: 24px; }
.simple li { margin-bottom: 8px; }

@media (max-width: 820px) {
  .layout { grid-template-columns: minmax(0, 1fr); }
  nav.rail { display: none; }
  .rail-select { display: block; width: 100%; font: inherit; font-size: 16px; padding: 10px 12px; border-radius: 9px; border: 1.5px solid var(--line); background: var(--surface); color: var(--ink); margin-bottom: 12px; }
  body { font-size: 16px; }
  .question { font-size: 17.5px; }
}
@media (prefers-reduced-motion: reduce) { .bar > span { transition: none; } }