:root {
  --bg: #0f1b2d; --bg2: #172a45; --card: #1d3557; --card2: #24426b; --ink: #f4f1e8; --mute: #9fb3cf;
  --amber: #ffc857; --ok: #3ddc97; --bad: #ff6b6b; --blue: #6ec1ff; --line: #3a5a86;
}
* { box-sizing: border-box; -webkit-tap-highlight-color: transparent; }
html, body { margin: 0; background: var(--bg); color: var(--ink); font-family: "Segoe UI", system-ui, -apple-system, Roboto, sans-serif; font-size: 18px; line-height: 1.45; }
body { min-height: 100vh; background: radial-gradient(1200px 600px at 80% -10%, #1f3c66 0%, var(--bg) 60%); user-select: none; -webkit-user-select: none; }
#app { max-width: 980px; margin: 0 auto; padding: 14px 16px 90px; }
h1, h2, h3 { margin: .3em 0; line-height: 1.2; }
h1 { font-size: 1.7rem; } h2 { font-size: 1.35rem; } h3 { font-size: 1.1rem; }
button { font: inherit; color: inherit; cursor: pointer; border: 0; }
.btn { min-height: 56px; padding: 12px 22px; border-radius: 16px; background: var(--card2); border: 2px solid var(--line); font-weight: 600; }
.btn:active { transform: scale(.98); }
.btn.primary { background: var(--amber); color: #2a1d00; border-color: #ffdf94; }
.btn.ok { background: var(--ok); color: #05301e; border-color: #8cf0c3; }
.btn.ghost { background: transparent; }
.btn[disabled] { opacity: .45; }
.row { display: flex; gap: 12px; flex-wrap: wrap; align-items: center; }
.sp { flex: 1; }
.top { display: flex; align-items: center; gap: 10px; padding: 6px 0 12px; }
.top .back { min-height: 48px; padding: 8px 16px; }
.chips { display: flex; gap: 8px; flex-wrap: wrap; }
.chip { background: var(--bg2); border: 1px solid var(--line); border-radius: 999px; padding: 4px 12px; font-size: .9rem; color: var(--mute); }
.chip b { color: var(--amber); }
.card { background: var(--card); border: 2px solid var(--line); border-radius: 20px; padding: 16px 18px; margin: 12px 0; }
.island { display: flex; gap: 16px; align-items: center; width: 100%; text-align: left; }
.island .ic { font-size: 3rem; width: 72px; text-align: center; }
.island .tx { flex: 1; } .island small { color: var(--mute); display: block; }
.bar { height: 10px; background: var(--bg); border-radius: 99px; overflow: hidden; margin-top: 8px; }
.bar i { display: block; height: 100%; background: linear-gradient(90deg, var(--blue), var(--ok)); }
.topic { background: #2b2210; border: 2px solid var(--amber); color: var(--amber); border-radius: 14px; padding: 8px 14px; font-weight: 700; margin: 6px 0 10px; }
.skill { display: inline-block; background: var(--bg2); border: 1px dashed var(--blue); color: var(--blue); border-radius: 10px; padding: 3px 10px; font-size: .88rem; margin-bottom: 6px; }
.grid { display: grid; gap: 12px; grid-template-columns: 1fr; }
@media (min-width: 760px) { .grid.two { grid-template-columns: 1fr 1fr; } .case-wrap { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; } }
.stars { letter-spacing: 2px; color: var(--amber); white-space: nowrap; }
.dim { opacity: .35; }
.steps { display: flex; gap: 8px; flex-wrap: wrap; margin: 8px 0; }
.dot { min-width: 44px; height: 44px; border-radius: 12px; background: var(--bg2); border: 2px solid var(--line); font-weight: 700; }
.dot.cur { border-color: var(--amber); color: var(--amber); } .dot.done { background: #12402e; border-color: var(--ok); color: var(--ok); } .dot.weak { background: #4a2a10; border-color: #ff9d4d; color: #ff9d4d; }
.q { font-size: 1.18rem; font-weight: 600; margin: 6px 0 12px; }
.part { background: var(--bg2); border: 2px solid var(--line); border-radius: 16px; padding: 12px 14px; margin: 10px 0; }
.part.right { border-color: var(--ok); background: #0f3326; } .part.wrong { border-color: var(--bad); background: #3a1a22; }
.part label.l { display: block; margin-bottom: 6px; color: var(--mute); font-weight: 600; }
.field { display: inline-flex; align-items: center; gap: 6px; }
.field input { width: 170px; height: 56px; font: inherit; font-size: 1.35rem; font-weight: 700; text-align: center; border-radius: 12px; border: 3px solid var(--line); background: #0b1626; color: var(--ink); caret-color: transparent; }
.field input.act { border-color: var(--amber); box-shadow: 0 0 0 4px #ffc85733; }
.opts { display: grid; gap: 8px; }
.opt { text-align: left; padding: 12px 16px; min-height: 54px; border-radius: 14px; border: 2px solid var(--line); background: var(--card2); }
.opt.sel { border-color: var(--amber); background: #3b3213; } .opt.right { border-color: var(--ok); background: #145a3d; } .opt.wrong { border-color: var(--bad); }
.pad { display: grid; grid-template-columns: repeat(6, 1fr); gap: 8px; margin-top: 12px; max-width: 520px; }
.pad button { height: 58px; border-radius: 14px; background: var(--card2); border: 2px solid var(--line); font-size: 1.4rem; font-weight: 700; }
.pad button.w2 { grid-column: span 2; font-size: 1rem; }
.fb { border-radius: 16px; padding: 12px 16px; margin: 10px 0; font-weight: 600; }
.fb.ok { background: #0f3326; border: 2px solid var(--ok); } .fb.no { background: #3a1a22; border: 2px solid var(--bad); } .fb.hint { background: #14304d; border: 2px solid var(--blue); font-weight: 500; }
.expl { background: #14243c; border: 2px solid var(--line); border-radius: 16px; padding: 12px 16px; margin: 10px 0; font-weight: 500; }
.fig { width: 100%; max-width: 420px; background: #f6f3ea; border-radius: 16px; display: block; margin: 8px auto; }
.fig .ln { stroke: #1d2b44; stroke-width: 2.4; } .fig .cn { stroke: #3b82c4; stroke-width: 1.8; } .fig .ex { stroke: #1d2b44; stroke-width: 2; stroke-dasharray: 6 5; }
.fig .rt { stroke: #1d2b44; stroke-width: 1.6; fill: none; } .fig .ar { stroke: #b0533b; stroke-width: 2; fill: none; } .fig .ar.hl { stroke: #e08a00; stroke-width: 3.4; }
.fig .lbl { font: italic 700 17px "Times New Roman", serif; fill: #1d2b44; } .fig .val { font: 700 12px "Segoe UI", sans-serif; fill: #8a3a26; } .fig .val.hl { font-size: 17px; fill: #e08a00; }
table.tb { border-collapse: collapse; margin: 8px 8px 8px 0; background: var(--bg2); }
table.tb td, table.tb th { border: 2px solid var(--line); padding: 8px 18px; text-align: center; }
.tbs { display: flex; flex-wrap: wrap; } .rol { font-size: 1.3rem; font-weight: 700; letter-spacing: 1px; margin: 8px 0; color: var(--amber); }
.big { font-size: 3rem; text-align: center; } .center { text-align: center; }
.hero { display: flex; align-items: center; gap: 14px; }
.hero .face { font-size: 3.4rem; }
.timer { font-variant-numeric: tabular-nums; }
.bars .r { display: grid; grid-template-columns: 1fr 70px; gap: 8px; align-items: center; margin: 8px 0; }
.pop { animation: pop .35s ease; } @keyframes pop { 0% { transform: scale(.9); opacity: 0 } 100% { transform: scale(1); opacity: 1 } }
small, .small { color: var(--mute); }

@media (min-width: 760px) { .sticky { position: sticky; top: 10px; align-self: start; } }