:root {
  --bg: #0e1116;
  --panel: #161b22;
  --panel-2: #1d232c;
  --line: #2a313c;
  --text: #e8ecf1;
  --muted: #9aa5b4;
  --accent: #5fb3ff;
  --on-accent: #0e1116;
  --fire: #ff8a3d;
  --fire-dim: #4a3426;
  --ok: #3ecf8e;
  --ok-bg: #11291f;
  --bad: #ff6b6b;
  --bad-bg: #2d1518;
  --radius: 14px;
  --font: "SF Pro Text", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --mono: "SF Mono", ui-monospace, Menlo, monospace;
}
@media (prefers-color-scheme: light) {
  :root {
    --bg: #f6f7f9; --panel: #ffffff; --panel-2: #f0f2f5; --line: #dde2e8;
    --text: #141a21; --muted: #5a6573; --accent: #0b6bcb; --on-accent: #ffffff; --fire: #d9600f; --fire-dim: #f6e2d4;
    --ok: #13804f; --ok-bg: #e3f5ec; --bad: #c4302b; --bad-bg: #fbe7e6;
  }
}
* { box-sizing: border-box; }
html, body { margin: 0; background: var(--bg); color: var(--text); font: 16px/1.5 var(--font); -webkit-text-size-adjust: 100%; }
main { max-width: 640px; margin: 0 auto; padding: max(16px, env(safe-area-inset-top)) 16px max(24px, env(safe-area-inset-bottom)); min-height: 100dvh; display: flex; flex-direction: column; gap: 16px; }
button { font: inherit; color: inherit; cursor: pointer; border: 0; }
.btn { background: var(--accent); color: var(--on-accent); border-radius: var(--radius); padding: 15px 18px; font-weight: 650; width: 100%; font-size: 17px; }
.btn:disabled { opacity: .45; cursor: default; }
.btn.ghost { background: transparent; border: 1px solid var(--line); color: var(--text); }
.muted { color: var(--muted); }
.small { font-size: 13px; }

/* topo */
.top { display: flex; align-items: center; justify-content: space-between; }
.brand { font-weight: 700; letter-spacing: .02em; }
.brand span { color: var(--muted); font-weight: 500; }
.chips { display: flex; gap: 8px; }
.chip { display: inline-flex; align-items: center; gap: 6px; background: var(--panel); border: 1px solid var(--line); border-radius: 999px; padding: 5px 11px; font-weight: 650; font-variant-numeric: tabular-nums; }
.chip.fire.on { color: var(--fire); border-color: var(--fire); }
.chip.fire.off { color: var(--muted); }
.flame { width: 16px; height: 16px; }

/* cartão do dia */
.card { background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius); padding: 18px; }
.today { display: grid; grid-template-columns: 96px 1fr; gap: 18px; align-items: center; }
.ring { width: 96px; height: 96px; }
.ring circle { fill: none; stroke-width: 9; }
.ring .bg { stroke: var(--panel-2); }
.ring .fg { stroke: var(--fire); stroke-linecap: round; transition: stroke-dashoffset .5s; }
.ring text { fill: var(--text); font: 700 22px var(--font); }
.ring .sub { fill: var(--muted); font: 500 11px var(--font); }
.today h2 { margin: 0 0 4px; font-size: 19px; }
.week { display: flex; gap: 6px; margin-top: 10px; }
.day { flex: 1; text-align: center; font-size: 11px; color: var(--muted); }
.day i { display: block; height: 8px; border-radius: 4px; background: var(--panel-2); margin-bottom: 4px; }
.day.lit i { background: var(--fire); }
.day.part i { background: var(--fire-dim); }
.facts { display: flex; gap: 18px; margin: 4px 0 0; }
.facts b { display: block; font-size: 20px; font-variant-numeric: tabular-nums; }

/* navegação */
.link { background: none; padding: 4px 0; color: var(--muted); font-weight: 600; }
.brand.link { color: var(--text); font-weight: 700; font-size: 16px; }
.login .logo { width: 88px; height: 88px; align-self: center; }
.brand.big { font-size: 28px; margin-bottom: 8px; text-align: center; }
.tabs { display: flex; gap: 6px; background: var(--panel); border: 1px solid var(--line); border-radius: 999px; padding: 4px; }
.tab { flex: 1; background: none; border-radius: 999px; padding: 9px 0; font-weight: 650; color: var(--muted); }
.tab.on { background: var(--panel-2); color: var(--text); }
.h { margin: 8px 0 0; font-size: 22px; }
.discs { display: flex; flex-direction: column; gap: 10px; }
.disc { display: flex; flex-direction: column; gap: 2px; text-align: left; width: 100%; }
.disc b { font-size: 20px; }
.disc.on { border-color: var(--accent); }

/* texto-base */
.doc h1 { margin: 0 0 12px; font-size: 24px; }
.toc { margin: 14px 0 6px; padding-left: 20px; color: var(--muted); }
.toc a { color: var(--accent); text-decoration: none; }
.block h2 { margin: 28px 0 6px; font-size: 20px; padding-top: 14px; border-top: 1px solid var(--line); }
.sec { padding: 12px 0; scroll-margin-top: 12px; }
.sec h3 { margin: 8px 0 6px; font-size: 17px; }
.sec p { margin: 0 0 12px; line-height: 1.65; font-size: 16px; }
.sec-head { display: flex; gap: 6px; flex-wrap: wrap; }
.sec.here { border-left: 3px solid var(--fire); padding-left: 12px; margin-left: -15px; }
.tag.seen { color: var(--accent); }
.tag.mastered { color: var(--ok); }

/* lição do dia */
.suggest { display: flex; flex-direction: column; gap: 6px; }
.suggest .eyebrow { font-size: 12px; font-weight: 700; letter-spacing: .08em; text-transform: uppercase; color: var(--fire); }
.suggest h2 { margin: 0; font-size: 20px; line-height: 1.3; }
.suggest p { margin: 0; }
.topics { margin: 6px 0 10px; padding-left: 18px; color: var(--muted); font-size: 14px; }
.topics li { margin: 2px 0; }

/* going deeper */
.deeper { background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius); padding: 0 16px; }
.deeper summary { cursor: pointer; padding: 14px 0; font-weight: 700; color: var(--accent); list-style: none; }
.deeper summary::-webkit-details-marker { display: none; }
.deeper summary::before { content: "+ "; }
.deeper[open] summary::before { content: "− "; }
.deeper p { margin: 0 0 14px; line-height: 1.6; font-size: 15px; }

/* trilha */
.trail h3 { margin: 6px 0 10px; font-size: 14px; text-transform: uppercase; letter-spacing: .08em; color: var(--muted); }
.unit { display: grid; grid-template-columns: 1fr auto; gap: 4px 12px; padding: 12px 0; border-top: 1px solid var(--line); }
.unit:first-of-type { border-top: 0; }
.unit .t { font-weight: 600; }
.unit .n { color: var(--muted); font-size: 13px; font-variant-numeric: tabular-nums; text-align: right; }
.bar { grid-column: 1 / -1; height: 6px; background: var(--panel-2); border-radius: 3px; overflow: hidden; }
.bar i { display: block; height: 100%; background: var(--accent); border-radius: 3px; }
.unit.done .bar i { background: var(--ok); }

/* questão */
.qhead { display: flex; align-items: center; gap: 12px; }
.qhead .x { background: none; color: var(--muted); font-size: 22px; padding: 4px 6px; line-height: 1; }
.prog { flex: 1; height: 10px; background: var(--panel); border-radius: 5px; overflow: hidden; border: 1px solid var(--line); }
.prog i { display: block; height: 100%; background: var(--ok); transition: width .3s; }
.qmeta { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }
.tag { font-size: 12px; font-weight: 700; letter-spacing: .06em; text-transform: uppercase; padding: 3px 8px; border-radius: 6px; background: var(--panel-2); color: var(--muted); }
.tag.new { background: var(--accent); color: var(--on-accent); }
.prompt { font-size: 20px; line-height: 1.4; font-weight: 600; margin: 4px 0; }
.opts { display: flex; flex-direction: column; gap: 10px; }
.opt { text-align: left; background: var(--panel); border: 1.5px solid var(--line); border-radius: var(--radius); padding: 14px 14px 14px 52px; position: relative; min-height: 54px; font-size: 16px; }
.opt::before { content: attr(data-k); position: absolute; left: 14px; top: 13px; width: 26px; height: 26px; border-radius: 7px; border: 1.5px solid var(--line); display: grid; place-items: center; font-size: 13px; font-weight: 700; color: var(--muted); }
.opt:not(:disabled):hover { border-color: var(--accent); }
.opt .val { font-family: var(--mono); font-size: 15px; }
.opt .why { display: none; margin-top: 8px; font-size: 14px; color: var(--muted); line-height: 1.45; }
.answered .opt .why { display: block; }
.answered .opt { cursor: default; }
.opt.right { border-color: var(--ok); background: var(--ok-bg); }
.opt.right::before { content: "✓"; border-color: var(--ok); color: var(--ok); }
.opt.wrong { border-color: var(--bad); background: var(--bad-bg); }
.opt.wrong::before { content: "✗"; border-color: var(--bad); color: var(--bad); }
.opt.right .why, .opt.wrong .why { color: var(--text); }
.verdict { border-radius: var(--radius); padding: 14px 16px; font-weight: 650; }
.verdict.ok { background: var(--ok-bg); color: var(--ok); }
.verdict.bad { background: var(--bad-bg); color: var(--bad); }
.verdict p { margin: 4px 0 0; font-weight: 500; color: var(--text); font-size: 14px; }
.src { font-size: 13px; color: var(--muted); }
.foot { margin-top: auto; position: sticky; bottom: 0; padding-top: 12px; background: linear-gradient(transparent, var(--bg) 30%); }

/* fim */
.end { text-align: center; padding-top: 40px; display: flex; flex-direction: column; gap: 18px; align-items: center; }
.end .big { font-size: 64px; line-height: 1; }
.end h2 { margin: 0; font-size: 26px; }
.score { display: flex; gap: 12px; width: 100%; }
.score .card { flex: 1; text-align: center; }
.score b { display: block; font-size: 26px; font-variant-numeric: tabular-nums; }

/* login */
.login { margin: auto 0; display: flex; flex-direction: column; gap: 12px; }
.login input { font: inherit; padding: 14px; border-radius: var(--radius); border: 1px solid var(--line); background: var(--panel); color: var(--text); }
.err { color: var(--bad); font-size: 14px; min-height: 20px; }
@media (prefers-reduced-motion: reduce) { * { transition: none !important; } }