/* Study course design system.
   Two semantic accents:  CONCEPT (blue)  = core idea / explanation / answer
                          WATCH OUT (amber) = gotchas, confusions, mistakes
   Success/danger are reserved for exam results so they never compete with those two.
   No web fonts or CDN: the site must work offline from file://. */

:root, :root[data-theme="dark"] {
  color-scheme: dark;
  --bg: #0b0f17;           --surface: #121825;      --elevated: #182033;    --sunken: #080b12;
  --border: #222b3d;       --border-strong: #33405a;
  --text: #e8ecf4;         --text-2: #b4bdcf;       --muted: #8691a8;
  --primary: #7aa8ff;      --primary-ink: #081020;  --primary-hover: #9cbfff;
  --primary-grad: linear-gradient(135deg, #6f9dff 0%, #8f7dff 100%);
  --concept: #7aa8ff;      --concept-bg: rgba(122,168,255,.08);  --concept-line: rgba(122,168,255,.32);
  --watch: #f3b552;        --watch-bg: rgba(243,181,82,.075);    --watch-line: rgba(243,181,82,.34);
  --success: #4fcf93;      --success-bg: rgba(79,207,147,.12);
  --danger: #f27a7a;       --danger-bg: rgba(242,122,122,.12);
  --code-bg: #0a0e17;      --code-text: #d7deec;    --code-border: #1f293b;  --code-head: #0f1522;
  --inline-code-bg: rgba(122,168,255,.10); --inline-code-text: #a9c6ff;
  --tk-kw: #c792ea; --tk-str: #c3e88d; --tk-num: #f78c6c; --tk-com: #6b7891; --tk-pre: #89ddff; --tk-fn: #82aaff; --tk-std: #ffcb6b;
  --hover: rgba(255,255,255,.045);    --selected: rgba(122,168,255,.13);
  --focus: #9cc4ff;
  --shadow-sm: 0 1px 2px rgba(0,0,0,.3);
  --shadow: 0 1px 2px rgba(0,0,0,.35), 0 10px 30px rgba(0,0,0,.25);
  --scrim: rgba(4,6,10,.65);
  --hero-glow: radial-gradient(1200px 400px at 10% -10%, rgba(111,157,255,.16), transparent 60%),
               radial-gradient(800px 300px at 90% 0%, rgba(143,125,255,.12), transparent 60%);
  --m0: #7aa8ff; --m1: #b392ff; --m2: #4fd1c5; --m3: #7bd88f;
}
:root[data-theme="light"] {
  color-scheme: light;
  --bg: #f6f7fa;          --surface: #ffffff;      --elevated: #ffffff;    --sunken: #eef0f5;
  --border: #e1e5ed;      --border-strong: #c9d0dc;
  --text: #151b28;        --text-2: #475266;       --muted: #6a7488;
  --primary: #2459d6;     --primary-ink: #ffffff;  --primary-hover: #1c47ad;
  --primary-grad: linear-gradient(135deg, #2b62e3 0%, #5b4ce0 100%);
  --concept: #2459d6;     --concept-bg: #f0f5ff;   --concept-line: #c4d5f7;
  --watch: #9a5800;       --watch-bg: #fff7e8;     --watch-line: #f0d29d;
  --success: #15804e;     --success-bg: #e5f5ec;
  --danger: #b3261e;      --danger-bg: #fbe9e7;
  --code-bg: #f7f8fb;     --code-text: #1f2937;    --code-border: #e1e5ed;  --code-head: #eef1f6;
  --inline-code-bg: #eef2fa; --inline-code-text: #1c4fb8;
  --tk-kw: #8a2bb9; --tk-str: #1f7a35; --tk-num: #b35309; --tk-com: #7b8496; --tk-pre: #0b7285; --tk-fn: #1d4ed8; --tk-std: #a15c00;
  --hover: rgba(20,30,50,.045);       --selected: rgba(36,89,214,.09);
  --focus: #2459d6;
  --shadow-sm: 0 1px 2px rgba(20,30,50,.06);
  --shadow: 0 1px 2px rgba(20,30,50,.05), 0 8px 24px rgba(20,30,50,.07);
  --scrim: rgba(20,26,38,.42);
  --hero-glow: radial-gradient(1200px 400px at 10% -10%, rgba(43,98,227,.09), transparent 60%),
               radial-gradient(800px 300px at 90% 0%, rgba(91,76,224,.07), transparent 60%);
  --m0: #2459d6; --m1: #6d3fd6; --m2: #0f8a80; --m3: #2f8a3f;
}

/* ---------- base ---------- */
* { box-sizing: border-box; }
/* smooth scrolling only after load, so arriving at page.html#anchor jumps straight there */
html { scroll-padding-top: 80px; }
html.smooth { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html, html.smooth { scroll-behavior: auto; } * { transition: none !important; animation: none !important; } }
body { margin: 0; background: var(--bg); color: var(--text);
  font-family: "Inter", ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 16px; line-height: 1.7; -webkit-font-smoothing: antialiased; -webkit-text-size-adjust: 100%; font-feature-settings: "cv11", "ss01"; }
button, input, textarea, select { font-family: inherit; }
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 3px; }
:focus-visible { outline: 2px solid var(--focus); outline-offset: 2px; border-radius: 6px; }
::selection { background: var(--selected); }
.skip { position: absolute; left: -999px; top: 8px; background: var(--primary); color: var(--primary-ink); padding: 8px 14px; border-radius: 8px; z-index: 100; }
.skip:focus { left: 8px; }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
kbd { font: 600 11.5px/1 ui-monospace, SFMono-Regular, Consolas, monospace; background: var(--elevated); border: 1px solid var(--border-strong); border-bottom-width: 2px; border-radius: 5px; padding: 2px 6px; color: var(--text-2); }
[hidden] { display: none !important; }
:root { --mono: "JetBrains Mono", "Cascadia Code", "Fira Code", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; }

/* ---------- top bar ---------- */
.topbar { position: sticky; top: 0; z-index: 40; height: 60px; display: flex; align-items: center; gap: 12px; padding: 0 18px;
  background: color-mix(in srgb, var(--bg) 82%, transparent); backdrop-filter: saturate(160%) blur(12px); -webkit-backdrop-filter: saturate(160%) blur(12px);
  border-bottom: 1px solid var(--border); }
.brand { display: flex; align-items: center; gap: 11px; color: var(--text); font-weight: 700; letter-spacing: -.005em; }
.brand:hover { text-decoration: none; }
.brand-mark { display: grid; place-items: center; width: 34px; height: 34px; border-radius: 9px; background: var(--primary-grad); color: #fff;
  font: 800 12px/1 var(--mono); box-shadow: 0 2px 10px rgba(80,110,255,.35); }
.brand-text { display: flex; flex-direction: column; line-height: 1.15; font-size: 15px; }
.brand-text small { font-size: 11.5px; font-weight: 500; color: var(--muted); letter-spacing: .01em; }
.spacer { flex: 1; }
.iconbtn { display: none; width: 40px; height: 40px; border-radius: 10px; border: 1px solid var(--border); background: var(--surface); color: var(--text); font-size: 18px; cursor: pointer; }
.searchbtn { display: flex; align-items: center; gap: 10px; min-width: 300px; height: 38px; padding: 0 8px 0 12px; background: var(--surface); color: var(--muted);
  border: 1px solid var(--border); border-radius: 10px; cursor: pointer; font-size: 14px; transition: border-color .15s, color .15s; }
.searchbtn:hover { border-color: var(--border-strong); color: var(--text-2); }
.searchbtn-text { flex: 1; text-align: left; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.theme-switch { display: flex; padding: 3px; gap: 2px; background: var(--surface); border: 1px solid var(--border); border-radius: 10px; }
.theme-switch button { border: 0; background: transparent; color: var(--text-2); font-size: 13px; font-weight: 600; line-height: 1; padding: 8px 11px; border-radius: 7px; cursor: pointer; min-height: 32px; }
.theme-switch button:hover { background: var(--hover); }
.theme-switch button[aria-pressed="true"] { background: var(--selected); color: var(--primary); }
.readbar { position: absolute; left: 0; right: 0; bottom: -1px; height: 2px; pointer-events: none; }
.readbar span { display: block; height: 100%; width: 0; background: var(--primary-grad); }

/* ---------- layout & sidebar ---------- */
.layout { display: grid; grid-template-columns: 288px minmax(0, 1fr); min-height: calc(100vh - 60px); }
.sidebar { position: sticky; top: 60px; align-self: start; height: calc(100vh - 60px); overflow-y: auto; padding: 14px 12px 40px; background: var(--surface);
  border-right: 1px solid var(--border); scrollbar-width: thin; scrollbar-color: var(--border-strong) transparent; }
.sb-home, .sb-plain { display: flex; justify-content: space-between; align-items: center; padding: 8px 10px; border-radius: 8px; color: var(--text); font-weight: 600; font-size: 14px; min-height: 38px; }
.sb-home:hover, .sb-plain:hover { background: var(--hover); text-decoration: none; }
.is-current { background: var(--selected) !important; color: var(--primary) !important; }
.sb-group { margin-top: 10px; }
.sb-group summary { display: flex; justify-content: space-between; align-items: center; cursor: pointer; list-style: none; padding: 7px 10px; border-radius: 8px;
  font-size: 11.5px; font-weight: 700; letter-spacing: .09em; text-transform: uppercase; color: var(--muted); }
.sb-group summary::-webkit-details-marker { display: none; }
.sb-group summary::before { content: "\25B8"; margin-right: 7px; transition: transform .15s; display: inline-block; font-size: 10px; }
.sb-group[open] summary::before { transform: rotate(90deg); }
.sb-group summary span:first-child { flex: 1; }
.sb-group summary:hover { background: var(--hover); color: var(--text-2); }
.sb-count { font-variant-numeric: tabular-nums; letter-spacing: 0; font-weight: 600; font-size: 11.5px; background: var(--sunken); border: 1px solid var(--border); padding: 1px 7px; border-radius: 20px; }
.sb-group ul { list-style: none; margin: 2px 0 0; padding: 0 0 0 8px; border-left: 1px solid var(--border); margin-left: 15px; }
.sb-link { position: relative; display: flex; align-items: center; gap: 9px; padding: 6px 10px; border-radius: 8px; color: var(--text-2); font-size: 13.5px; line-height: 1.35; min-height: 34px; }
.sb-link:hover { background: var(--hover); color: var(--text); text-decoration: none; }
.sb-link.is-current::before { content: ""; position: absolute; left: -9px; top: 6px; bottom: 6px; width: 2px; border-radius: 2px; background: var(--primary); }
.sb-num { font: 600 11.5px/1 var(--mono); color: var(--muted); width: 20px; flex: none; }
.sb-link.is-current .sb-num { color: var(--primary); }
.sb-title-text { flex: 1; }
.sb-check { width: 15px; height: 15px; flex: none; border-radius: 50%; border: 1.5px solid var(--border-strong); }
.sb-link.done .sb-check { background: var(--success); border-color: var(--success); position: relative; }
.sb-link.done .sb-check::after { content: ""; position: absolute; left: 4px; top: 1.5px; width: 3.5px; height: 7px; border: solid var(--bg); border-width: 0 2px 2px 0; transform: rotate(45deg); }
.sb-section { margin-top: 18px; padding-top: 12px; border-top: 1px solid var(--border); }
.sb-label { font-size: 11.5px; font-weight: 700; letter-spacing: .09em; text-transform: uppercase; color: var(--muted); padding: 0 10px 6px; }
.sb-plain { font-weight: 500; color: var(--text-2); font-size: 13.5px; }
.sb-badge { font-size: 11.5px; background: var(--sunken); border: 1px solid var(--border); border-radius: 20px; padding: 1px 8px; color: var(--muted); }
.scrim { position: fixed; inset: 60px 0 0 0; background: var(--scrim); z-index: 29; }

main { min-width: 0; outline: none; }
.page { max-width: 780px; margin: 0 auto; padding: 34px 32px 90px; }
.home.page, .qpage.page { max-width: 1040px; }

/* ---------- headings, crumbs ---------- */
.crumbs { display: flex; flex-wrap: wrap; gap: 7px; align-items: center; font-size: 13px; color: var(--muted); margin-bottom: 20px; }
.crumbs a { color: var(--text-2); }
.crumbs [aria-current] { color: var(--text); font-weight: 600; }
.eyebrow { display: flex; flex-wrap: wrap; align-items: center; gap: 6px 14px; font-size: 13px; color: var(--muted); margin-bottom: 10px; }
.meta-item { display: inline-flex; align-items: center; gap: 14px; }
.meta-item::before { content: ""; width: 3px; height: 3px; border-radius: 50%; background: var(--border-strong); }
.cat-tag { font-size: 11px; font-weight: 700; letter-spacing: .1em; text-transform: uppercase; color: var(--primary); background: var(--concept-bg); border: 1px solid var(--concept-line); padding: 4px 10px; border-radius: 20px; }
h1 { font-size: clamp(30px, 4.4vw, 42px); line-height: 1.12; margin: 6px 0 12px; font-weight: 800; letter-spacing: -.025em; }
h2 { font-size: 22px; line-height: 1.3; margin: 0 0 10px; font-weight: 700; letter-spacing: -.012em; }
h3 { font-size: 17px; margin: 0; letter-spacing: -.005em; }
.lead { font-size: 18.5px; line-height: 1.6; color: var(--text-2); margin: 0 0 22px; max-width: 62ch; }
p { margin: 12px 0; } ul, ol { padding-left: 22px; margin: 10px 0; } li { margin: 7px 0; }
li::marker { color: var(--muted); }
strong { font-weight: 650; color: var(--text); }

/* ---------- buttons, chips ---------- */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; min-height: 42px; padding: 9px 16px; border-radius: 10px;
  font-size: 14.5px; font-weight: 600; line-height: 1.2; cursor: pointer; border: 1px solid transparent; text-decoration: none !important;
  transition: background .15s, border-color .15s, transform .15s, box-shadow .15s; }
.btn:active { transform: translateY(1px); }
.btn-primary { background: var(--primary-grad); color: #fff; box-shadow: 0 4px 14px rgba(80,110,255,.28); }
.btn-primary:hover { box-shadow: 0 6px 20px rgba(80,110,255,.4); filter: brightness(1.06); }
.btn-ghost { background: var(--surface); color: var(--text); border-color: var(--border-strong); }
.btn-ghost:hover { background: var(--elevated); border-color: var(--primary); }
.btn-sm { min-height: 36px; padding: 6px 12px; font-size: 13.5px; }
.btn-lg { min-height: 48px; padding: 11px 20px; font-size: 15px; }
.btn[aria-pressed="true"] { border-color: var(--success); color: var(--success); background: var(--success-bg); }
.md-box { width: 16px; height: 16px; border: 1.5px solid currentColor; border-radius: 4px; position: relative; flex: none; }
.btn[aria-pressed="true"] .md-box { background: var(--success); border-color: var(--success); }
.btn[aria-pressed="true"] .md-box::after { content: ""; position: absolute; left: 4px; top: 0; width: 4px; height: 9px; border: solid var(--bg); border-width: 0 2px 2px 0; transform: rotate(45deg); }
.lesson-actions, .hero-actions { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 4px; }
.chip { display: inline-flex; align-items: center; gap: 6px; font-size: 11px; font-weight: 700; letter-spacing: .08em; text-transform: uppercase; padding: 3px 10px; border-radius: 20px; border: 1px solid; }
.chip-concept { color: var(--concept); background: var(--concept-bg); border-color: var(--concept-line); }
.chip-watch { color: var(--watch); background: var(--watch-bg); border-color: var(--watch-line); }
.legend-inline { display: flex; flex-wrap: wrap; align-items: center; gap: 6px 8px; font-size: 13px; color: var(--muted); margin: 18px 0 8px; padding-top: 18px; border-top: 1px solid var(--border); }
.legend-inline .chip-watch { margin-left: 10px; }

/* ---------- pager ---------- */
.pager { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin: 18px 0; }
.pager a { display: flex; flex-direction: column; gap: 3px; padding: 14px 16px; background: var(--surface); border: 1px solid var(--border); border-radius: 12px; color: var(--text); min-height: 66px;
  transition: border-color .15s, transform .15s, box-shadow .15s; }
.pager a:hover { border-color: var(--primary); text-decoration: none; box-shadow: var(--shadow-sm); transform: translateY(-1px); }
.pager .pg-next { text-align: right; }
.pg-dir { font-size: 11.5px; font-weight: 700; letter-spacing: .07em; text-transform: uppercase; color: var(--muted); }
.pg-title { font-weight: 600; font-size: 14.5px; }
.pager-bottom { margin-top: 36px; }

/* ---------- lesson layout + side TOC ---------- */
.lesson-wrap { display: grid; grid-template-columns: minmax(0, 1fr); }
.otp { display: none; }
@media (min-width: 1320px) {
  .lesson-wrap { grid-template-columns: minmax(0, 1fr) 240px; gap: 8px; max-width: 1100px; margin: 0 auto; padding-right: 24px; }
  .lesson-wrap .page { margin: 0; width: 100%; justify-self: end; }
  .otp { display: block; }
  .otp-inner { position: sticky; top: 92px; padding: 6px 0 20px 18px; border-left: 1px solid var(--border); max-height: calc(100vh - 110px); overflow-y: auto; }
  .lesson-wrap .toc { display: none; }
}
.otp-label { font-size: 11px; font-weight: 700; letter-spacing: .1em; text-transform: uppercase; color: var(--muted); margin-bottom: 8px; }
.otp ol { list-style: none; margin: 0 0 22px; padding: 0; }
.otp li { margin: 0; }
.otp a { display: flex; align-items: center; gap: 9px; padding: 5px 8px; margin-left: -8px; border-radius: 7px; color: var(--text-2); font-size: 13px; line-height: 1.35; }
.otp a::before { content: ""; width: 6px; height: 6px; border-radius: 50%; flex: none; background: var(--border-strong); }
.otp a.otp-concept::before { background: var(--concept); }
.otp a.otp-watch::before { background: var(--watch); }
.otp a:hover { color: var(--text); background: var(--hover); text-decoration: none; }
.otp a.is-active { color: var(--primary); background: var(--selected); font-weight: 600; }
.otp-progress { padding-top: 14px; border-top: 1px solid var(--border); }
.otp-progress .bar { margin: 4px 0 6px; }
.otp-progress-text { font-size: 12.5px; color: var(--muted); }

/* ---------- lesson blocks ---------- */
.callout { position: relative; margin: 22px 0; padding: 18px 22px 16px; border-radius: 14px; border: 1px solid var(--border); background: var(--surface); }
.callout::before { content: ""; position: absolute; left: -1px; top: 14px; bottom: 14px; width: 3px; border-radius: 0 3px 3px 0; }
.callout h2 { margin-top: 4px; font-size: 19.5px; }
.callout > :last-child { margin-bottom: 0; }
.callout.concept { background: var(--concept-bg); border-color: var(--concept-line); }
.callout.concept::before { background: var(--concept); }
.callout.watch { background: var(--watch-bg); border-color: var(--watch-line); }
.callout.watch::before { background: var(--watch); }
.callout-label { display: inline-flex; align-items: center; gap: 6px; font-size: 11px; font-weight: 800; letter-spacing: .12em; text-transform: uppercase; }
.concept > .callout-label, .ans .callout-label { color: var(--concept); }
.watch > .callout-label { color: var(--watch); }
.kp-list { list-style: none; padding: 0; margin: 12px 0 2px; counter-reset: kp; }
.kp-list li { position: relative; counter-increment: kp; padding: 10px 0 10px 42px; margin: 0; border-top: 1px dashed var(--concept-line); }
.kp-list li:first-child { border-top: 0; }
.kp-list li::before { content: counter(kp); position: absolute; left: 0; top: 10px; width: 26px; height: 26px; display: grid; place-items: center; border-radius: 8px;
  background: var(--surface); border: 1px solid var(--concept-line); color: var(--concept); font: 700 12.5px/1 var(--mono); }
.section { margin: 38px 0; }
.section h2 { padding-bottom: 8px; border-bottom: 1px solid var(--border); }
.toc { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; margin: 16px 0; font-size: 13px; }
.toc-label { color: var(--muted); font-weight: 700; font-size: 11px; letter-spacing: .1em; text-transform: uppercase; margin-right: 4px; }
.toc a { background: var(--surface); border: 1px solid var(--border); border-radius: 20px; padding: 4px 12px; color: var(--text-2); }
.toc a:hover { border-color: var(--primary); color: var(--primary); text-decoration: none; }
.pairs { display: grid; gap: 10px; margin-top: 12px; }
.pair { padding: 12px 16px; background: var(--surface); border: 1px solid var(--watch-line); border-radius: 11px; }
.pair .vs { font: 700 14px/1.45 var(--mono); color: var(--watch); margin-bottom: 4px; }
.pair .vs code { background: none; color: inherit; padding: 0; font-size: inherit; }
.pair .d { color: var(--text); font-size: 15px; }
.test-card { display: flex; gap: 18px; align-items: flex-start; margin: 34px 0; padding: 22px 24px; border-radius: 16px; background: var(--hero-glow), var(--surface); border: 1px solid var(--border-strong); box-shadow: var(--shadow); }
.test-icon { flex: none; width: 46px; height: 46px; border-radius: 12px; display: grid; place-items: center; background: var(--primary-grad); color: #fff; font: 800 22px/1 var(--mono); }
.test-body { flex: 1; min-width: 0; }
.test-card h2 { margin: 2px 0 4px; }
.test-card p { margin: 0 0 14px; color: var(--text-2); }
.test-actions { display: flex; flex-wrap: wrap; gap: 10px; }
.extra-links, .extras { display: grid; gap: 10px; } .extras { grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 14px; }
.extra-link { display: flex; flex-direction: column; gap: 3px; padding: 14px 16px; background: var(--surface); border: 1px solid var(--border); border-radius: 12px; color: var(--text);
  transition: border-color .15s, transform .15s, box-shadow .15s; }
.extra-link strong::after { content: " \2197"; color: var(--muted); font-weight: 500; }
.extra-link:hover { border-color: var(--primary); text-decoration: none; transform: translateY(-1px); box-shadow: var(--shadow-sm); }
.extra-link span { color: var(--muted); font-size: 13.5px; line-height: 1.5; }

/* ---------- code ---------- */
code { background: var(--inline-code-bg); color: var(--inline-code-text); padding: 1.5px 6px; border-radius: 5px; font: 500 .86em var(--mono); overflow-wrap: anywhere; }
figure.code { margin: 18px 0; border: 1px solid var(--code-border); border-radius: 12px; background: var(--code-bg); overflow: hidden; box-shadow: var(--shadow-sm); }
figure.code figcaption { display: flex; align-items: center; gap: 12px; padding: 7px 8px 7px 14px; background: var(--code-head); border-bottom: 1px solid var(--code-border); }
.dots { display: inline-flex; gap: 6px; } .dots i { width: 10px; height: 10px; border-radius: 50%; background: var(--border-strong); opacity: .7; }
.lang { flex: 1; font: 700 11px/1 var(--mono); letter-spacing: .08em; text-transform: uppercase; color: var(--muted); }
.copy { font-size: 12px; font-weight: 600; line-height: 1; color: var(--text-2); background: transparent; border: 1px solid var(--border-strong); border-radius: 7px; padding: 6px 12px; min-height: 28px; cursor: pointer; }
.copy:hover { color: var(--text); border-color: var(--primary); }
.copy.copied { color: var(--success); border-color: var(--success); }
figure.code pre { margin: 0; padding: 16px 18px; overflow-x: auto; font: 13.5px/1.7 var(--mono); color: var(--code-text); tab-size: 4; }
figure.code pre code { background: none; color: inherit; padding: 0; font: inherit; overflow-wrap: normal; }
.tk-kw { color: var(--tk-kw); } .tk-str { color: var(--tk-str); } .tk-num { color: var(--tk-num); }
.tk-com { color: var(--tk-com); font-style: italic; } .tk-pre { color: var(--tk-pre); } .tk-fn { color: var(--tk-fn); } .tk-std { color: var(--tk-std); }

/* ---------- home ---------- */
.hero { position: relative; display: grid; grid-template-columns: minmax(0, 1fr) 270px; gap: 28px; align-items: center; padding: 34px 34px 32px; margin: -6px 0 0;
  border-radius: 20px; border: 1px solid var(--border); background: var(--hero-glow), var(--surface); box-shadow: var(--shadow); }
.hero h1 { font-size: clamp(30px, 4.6vw, 46px); }
.hero .lead { margin-bottom: 24px; }
.hero-card { display: flex; flex-direction: column; align-items: center; gap: 14px; text-align: center; padding: 22px 18px; border-radius: 16px; background: var(--bg); border: 1px solid var(--border); }
.ring { --p: 0; width: 132px; height: 132px; border-radius: 50%; display: grid; place-items: center;
  background: conic-gradient(var(--primary) calc(var(--p) * 1%), var(--border) 0); transition: background .4s; }
.ring-in { width: 108px; height: 108px; border-radius: 50%; background: var(--bg); display: flex; flex-direction: column; align-items: center; justify-content: center; }
.ring-in b { font-size: 28px; line-height: 1; letter-spacing: -.02em; }
.ring-in span { font-size: 12px; color: var(--muted); margin-top: 4px; }
.hero-card-text { display: flex; flex-direction: column; gap: 3px; }
.hero-card-text b { font-size: 15px; }
.hero-card-text span { font-size: 13px; color: var(--muted); line-height: 1.45; }
.overall { width: 100%; }
.bar { flex: 1; height: 7px; background: var(--sunken); border: 1px solid var(--border); border-radius: 20px; overflow: hidden; }
.bar > span { display: block; height: 100%; width: 0; background: var(--primary-grad); border-radius: 20px; transition: width .3s; }
.stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px; margin: 18px 0 0; }
.stats div { display: flex; flex-direction: column; padding: 14px 18px; border-radius: 14px; background: var(--surface); border: 1px solid var(--border); }
.stats b { font-size: 26px; line-height: 1.15; letter-spacing: -.02em; font-variant-numeric: tabular-nums; }
.stats span { font-size: 12.5px; color: var(--muted); font-weight: 600; letter-spacing: .04em; text-transform: uppercase; }
.legend { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin: 16px 0 0; }
.legend-item { position: relative; padding: 16px 18px; border-radius: 14px; border: 1px solid var(--border); background: var(--surface); }
.legend-item.concept { border-color: var(--concept-line); background: var(--concept-bg); }
.legend-item.watch { border-color: var(--watch-line); background: var(--watch-bg); }
.legend-item p { margin: 8px 0 0; font-size: 14.5px; color: var(--text-2); }
.flow { list-style: none; padding: 0; margin: 0; display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px; counter-reset: step; }
.flow li { position: relative; counter-increment: step; margin: 0; padding: 16px 16px 16px 58px; border-radius: 14px; background: var(--surface); border: 1px solid var(--border); display: flex; flex-direction: column; }
.flow li::before { content: counter(step); position: absolute; left: 16px; top: 16px; width: 30px; height: 30px; border-radius: 50%; display: grid; place-items: center;
  background: var(--selected); color: var(--primary); font: 700 13px/1 var(--mono); border: 1px solid var(--concept-line); }
.flow b { font-size: 15px; }
.flow span { color: var(--muted); font-size: 13.5px; line-height: 1.5; }
.section-title { margin: 44px 0 16px; font-size: 23px; }
.modules { display: grid; grid-template-columns: repeat(auto-fit, minmax(320px, 1fr)); gap: 16px; }
.module { --m: var(--m0); position: relative; display: flex; flex-direction: column; gap: 10px; padding: 22px 22px 18px; background: var(--surface); border: 1px solid var(--border); border-radius: 16px;
  box-shadow: var(--shadow-sm); overflow: hidden; transition: border-color .15s, box-shadow .15s; }
.module::before { content: ""; position: absolute; inset: 0 0 auto 0; height: 3px; background: var(--m); opacity: .85; }
.module:hover { border-color: color-mix(in srgb, var(--m) 50%, var(--border)); box-shadow: var(--shadow); }
.module.m1 { --m: var(--m1); } .module.m2 { --m: var(--m2); } .module.m3 { --m: var(--m3); }
.module-top { display: flex; gap: 14px; align-items: center; }
.module-icon { flex: none; width: 44px; height: 44px; border-radius: 12px; display: grid; place-items: center; font: 800 15px/1 var(--mono); color: var(--m);
  background: color-mix(in srgb, var(--m) 13%, transparent); border: 1px solid color-mix(in srgb, var(--m) 35%, transparent); }
.module-top h3 { font-size: 18.5px; }
.module-range { font: 600 12px/1.4 var(--mono); color: var(--muted); }
.module p { margin: 0; color: var(--text-2); font-size: 14.5px; line-height: 1.6; }
.module-meta { display: flex; gap: 8px; font-size: 12.5px; color: var(--text-2); }
.module-meta span { padding: 2px 9px; border-radius: 20px; background: var(--sunken); border: 1px solid var(--border); }
.module-prog { margin-top: 4px; }
.module .bar { flex: none; } .module .bar > span { background: var(--m); }
.module-progress-text { font-size: 12.5px; color: var(--muted); margin-top: 6px; }
.module-go { align-self: flex-start; margin-top: 4px; }
.module-list { border-top: 1px solid var(--border); padding-top: 4px; margin-top: 2px; }
.module-list summary { cursor: pointer; font-size: 13.5px; color: var(--text-2); padding: 6px 0; }
.module-list ol { list-style: none; margin: 4px 0 0; padding: 0; font-size: 14px; }
.module-list li { margin: 2px 0; }
.module-list a { display: flex; gap: 10px; padding: 4px 6px; border-radius: 6px; color: var(--text-2); }
.module-list a:hover { background: var(--hover); color: var(--text); text-decoration: none; }
.ml-num { font: 600 12px/1.9 var(--mono); color: var(--muted); }
.module-list a.done::after { content: "\2713"; margin-left: auto; color: var(--success); font-weight: 700; }
.foot-note { margin-top: 44px; padding-top: 18px; border-top: 1px solid var(--border); font-size: 13px; color: var(--muted); }

/* ---------- questions ---------- */
.qfilter { display: flex; flex-wrap: wrap; gap: 8px; margin: 14px 0 14px; }
.pill { font-size: 13.5px; font-weight: 600; line-height: 1; padding: 9px 14px; min-height: 38px; background: var(--surface); color: var(--text-2); border: 1px solid var(--border); border-radius: 20px; cursor: pointer; }
.pill span { color: var(--muted); font-weight: 500; margin-left: 4px; }
.pill:hover { border-color: var(--primary); }
.pill.is-active { background: var(--selected); color: var(--primary); border-color: var(--concept-line); }
.jump { margin: 0 0 8px; } .jump summary { cursor: pointer; color: var(--text-2); font-size: 14px; padding: 6px 0; }
.jump-group { display: flex; flex-wrap: wrap; gap: 6px; align-items: center; margin: 8px 0; font-size: 13px; }
.jump-group b { width: 100%; color: var(--muted); font-size: 11.5px; letter-spacing: .08em; text-transform: uppercase; }
.jump-group a { background: var(--surface); border: 1px solid var(--border); border-radius: 20px; padding: 3px 11px; color: var(--text-2); }
.qcat { margin: 46px 0 4px; font-size: 12px; letter-spacing: .12em; text-transform: uppercase; color: var(--primary); padding-bottom: 10px; border-bottom: 1px solid var(--border); }
.qtopic { display: flex; flex-wrap: wrap; align-items: baseline; gap: 4px 10px; margin: 30px 0 12px; font-size: 19px; }
.qtopic .n { font-family: var(--mono); font-size: 14px; color: var(--primary); background: var(--selected); padding: 2px 8px; border-radius: 7px; }
.qtopic .count { color: var(--muted); font-size: 13px; font-weight: 400; }
.qcard { margin: 14px 0; padding: 18px 22px; background: var(--surface); border: 1px solid var(--border); border-radius: 14px; box-shadow: var(--shadow-sm); transition: border-color .15s; }
.qcard:hover { border-color: var(--border-strong); }
.qcard:target { border-color: var(--primary); box-shadow: 0 0 0 3px var(--selected); }
.qmeta { display: flex; justify-content: space-between; align-items: center; gap: 12px; flex-wrap: wrap; font-size: 12.5px; margin-bottom: 8px; }
.qnum { font: 700 12px/1 var(--mono); color: var(--primary); background: var(--selected); border: 1px solid var(--concept-line); padding: 5px 9px; border-radius: 7px; letter-spacing: .02em; }
.qtopic-link { color: var(--muted); }
.qtext { font-weight: 600; font-size: 16.5px; line-height: 1.55; }
.qnote { margin-top: 8px; }
.expbox { margin-top: 8px; } .expbox summary { cursor: pointer; display: inline-block; list-style: none; font-size: 13.5px; color: var(--text-2); border-bottom: 1px dotted var(--muted); }
.expbox summary::-webkit-details-marker { display: none; }
.exp { margin-top: 8px; padding: 10px 14px; background: var(--sunken); border: 1px solid var(--border); border-radius: 9px; color: var(--text-2); font-size: 14.5px; }

/* ---------- exam ---------- */
.exambar { position: sticky; top: 72px; z-index: 20; margin: 14px 0 22px; padding: 12px 14px; background: color-mix(in srgb, var(--elevated) 92%, transparent); backdrop-filter: blur(10px);
  border: 1px solid var(--border-strong); border-radius: 14px; box-shadow: var(--shadow); }
.exam-row { display: flex; flex-wrap: wrap; align-items: center; gap: 12px; }
.progpill { font-weight: 700; font-size: 13.5px; color: var(--primary); background: var(--concept-bg); border: 1px solid var(--concept-line); padding: 6px 12px; border-radius: 20px; white-space: nowrap; font-variant-numeric: tabular-nums; }
.exam-bar { min-width: 120px; flex: 1; }
.exam-actions { display: flex; flex-wrap: wrap; gap: 8px; }
.qnav { margin-top: 8px; } .qnav summary { cursor: pointer; font-size: 13.5px; color: var(--text-2); }
.qnav-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(38px, 1fr)); gap: 6px; margin-top: 8px; max-height: 190px; overflow: auto; }
.qnav-grid a { text-align: center; padding: 7px 0; border: 1px solid var(--border); border-radius: 8px; color: var(--text-2); font-size: 12.5px; font-variant-numeric: tabular-nums; }
.qnav-grid a:hover { border-color: var(--primary); text-decoration: none; }
.qnav-grid a.answered { background: var(--success-bg); color: var(--success); border-color: var(--success); font-weight: 700; }
.ans-label { display: block; margin: 14px 0 6px; font-size: 11.5px; font-weight: 700; letter-spacing: .08em; text-transform: uppercase; color: var(--muted); }
.ansinput { width: 100%; min-height: 110px; padding: 12px 14px; background: var(--sunken); color: var(--text); border: 1px solid var(--border-strong); border-radius: 10px; font-size: 15px; line-height: 1.55; resize: vertical; transition: border-color .15s, box-shadow .15s; }
.ansinput:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px var(--selected); }
.ansinput.has-text { border-color: color-mix(in srgb, var(--success) 70%, var(--border-strong)); }

/* ---------- search modal ---------- */
.search-overlay { position: fixed; inset: 0; z-index: 60; background: var(--scrim); backdrop-filter: blur(3px); display: flex; justify-content: center; align-items: flex-start; padding: 9vh 16px 16px; }
.search-box { width: min(680px, 100%); max-height: 78vh; display: flex; flex-direction: column; background: var(--elevated); border: 1px solid var(--border-strong); border-radius: 16px; box-shadow: var(--shadow); overflow: hidden; }
.search-input { width: 100%; padding: 18px 20px; font-size: 17px; line-height: 1.3; color: var(--text); background: transparent; border: 0; border-bottom: 1px solid var(--border); outline: none; }
.search-results { overflow-y: auto; padding: 6px; }
.sr-item { display: flex; flex-direction: column; gap: 2px; padding: 10px 12px; border-radius: 10px; color: var(--text); }
.sr-item:hover, .sr-item.is-active { background: var(--selected); text-decoration: none; }
.sr-title { font-weight: 600; font-size: 15px; }
.sr-meta { font-size: 12.5px; color: var(--muted); }
.sr-kind { font-size: 10.5px; font-weight: 700; letter-spacing: .08em; text-transform: uppercase; color: var(--primary); margin-right: 8px; }
.sr-empty { padding: 24px; text-align: center; color: var(--muted); }
.search-foot { padding: 9px 14px; font-size: 12.5px; color: var(--muted); border-top: 1px solid var(--border); display: flex; gap: 14px; }

/* ---------- responsive ---------- */
@media (max-width: 1000px) {
  .layout { grid-template-columns: minmax(0, 1fr); }
  .iconbtn { display: inline-grid; place-items: center; }
  .sidebar { position: fixed; top: 60px; left: 0; bottom: 0; width: min(320px, 86vw); height: auto; z-index: 30; transform: translateX(-102%); transition: transform .22s; box-shadow: var(--shadow); }
  body.menu-open .sidebar { transform: none; }
  .searchbtn { min-width: 0; width: 40px; padding: 0; justify-content: center; } .searchbtn-text, .searchbtn kbd { display: none; }
  .hero { grid-template-columns: 1fr; }
  .hero-card { flex-direction: row; text-align: left; justify-content: flex-start; }
  .hero-card .overall { display: none; }
  .ring { width: 92px; height: 92px; flex: none; } .ring-in { width: 74px; height: 74px; } .ring-in b { font-size: 20px; } .ring-in span { font-size: 10.5px; }
  .flow { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 640px) {
  .topbar { padding: 0 12px; gap: 8px; }
  .page { padding: 22px 16px 64px; }
  .brand-text { display: none; }
  .ts-label { display: none; }
  .theme-switch button { padding: 8px 11px; }
  .hero { padding: 22px 18px; border-radius: 16px; gap: 18px; }
  .stats { grid-template-columns: 1fr 1fr; gap: 10px; }
  .stats div { padding: 12px 14px; }
  .legend, .pager, .flow { grid-template-columns: 1fr; }
  .modules { grid-template-columns: 1fr; }
  .exambar { top: 68px; padding: 8px 10px; } .exam-actions .btn { flex: 1; }
  .qcard { padding: 14px 14px; } .callout { padding: 16px 16px 14px; }
  .kp-list li { padding-left: 38px; }
  .test-card { flex-direction: column; padding: 18px; gap: 12px; }
  .test-actions .btn { flex: 1; }
  .pager .pg-next { text-align: left; }
  .lead { font-size: 17px; }
  .legend-inline .chip-watch { margin-left: 0; }
}
@media print {
  .topbar, .sidebar, .pager, .exambar, .lesson-actions, .otp, .test-actions, .readbar { display: none !important; }
  .layout, .lesson-wrap { display: block; } body { background: #fff; color: #000; }
}

/* ---------- compare mode (question bank + exam) ---------- */
/* no ligatures in code: some fonts would draw << as a single "\226A" glyph */
code, kbd, figure.code pre, .ansinput, .cmp-col.mine .cmp-body { font-variant-ligatures: none; font-feature-settings: "liga" 0, "calt" 0; }
.set-finish { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 12px; margin: 16px 0 8px; padding: 14px 18px;
  border-radius: 14px; border: 1px dashed var(--border-strong); background: var(--sunken); }
.sf-status { display: flex; flex-direction: column; gap: 2px; }
.sf-count { font-size: 14.5px; font-variant-numeric: tabular-nums; }
.sf-score { font-size: 13.5px; color: var(--text-2); font-variant-numeric: tabular-nums; }
.sf-actions { display: flex; flex-wrap: wrap; gap: 10px; }
.qset.is-comparing .set-finish { border-style: solid; border-color: var(--concept-line); background: var(--concept-bg); }
.qset.is-comparing .ansinput, .qset.is-comparing .ans-label, .qset:not(.is-comparing) .cmp { display: none; }
.exam:has(.qset.is-comparing) #btn-next { display: none; }
.cmp { margin-top: 14px; }
.cmp-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.cmp-col { position: relative; min-width: 0; padding: 12px 16px 14px; border-radius: 12px; border: 1px solid var(--border); background: var(--sunken); }
.cmp-col.model { background: var(--concept-bg); border-color: var(--concept-line); }
.cmp-col.model::before { content: ""; position: absolute; left: -1px; top: 12px; bottom: 12px; width: 3px; border-radius: 0 3px 3px 0; background: var(--concept); }
.cmp-h { font-size: 11px; font-weight: 800; letter-spacing: .1em; text-transform: uppercase; color: var(--muted); margin-bottom: 6px; }
.cmp-col.model .cmp-h { color: var(--concept); }
.cmp-body { font-size: 15px; line-height: 1.6; overflow-wrap: anywhere; }
.cmp-col.mine .cmp-body { white-space: pre-wrap; }
.cmp-body.is-empty { color: var(--muted); font-style: italic; }
.cmp-body > :first-child { margin-top: 0; } .cmp-body > :last-child { margin-bottom: 0; }
.selfmark { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; margin-top: 12px; }
.sm-label { font-size: 13px; color: var(--muted); margin-right: 4px; }
.selfmark button { min-height: 36px; padding: 6px 13px; border-radius: 9px; border: 1px solid var(--border-strong); background: var(--surface); color: var(--text-2);
  font-size: 13.5px; font-weight: 600; cursor: pointer; transition: border-color .15s, background .15s, color .15s; }
.selfmark button:hover { border-color: var(--primary); color: var(--text); }
.selfmark button[data-v="y"][aria-pressed="true"] { background: var(--success-bg); border-color: var(--success); color: var(--success); }
.selfmark button[data-v="p"][aria-pressed="true"] { background: var(--watch-bg); border-color: var(--watch); color: var(--watch); }
.selfmark button[data-v="n"][aria-pressed="true"] { background: var(--danger-bg); border-color: var(--danger); color: var(--danger); }
.qset.is-comparing .qcard[data-mark="y"] { border-color: color-mix(in srgb, var(--success) 55%, var(--border)); }
.qset.is-comparing .qcard[data-mark="p"] { border-color: color-mix(in srgb, var(--watch) 55%, var(--border)); }
.qset.is-comparing .qcard[data-mark="n"] { border-color: color-mix(in srgb, var(--danger) 55%, var(--border)); }
@media (max-width: 760px) { .cmp-grid { grid-template-columns: 1fr; } .set-finish { flex-direction: column; align-items: stretch; } .sf-actions .btn { flex: 1; } }
@media print { .set-finish, .selfmark { display: none !important; } }

/* ---------- question types ---------- */
.qtype { font-size: 11px; font-weight: 700; letter-spacing: .06em; text-transform: uppercase; color: var(--text-2); background: var(--sunken); border: 1px solid var(--border); padding: 3px 8px; border-radius: 7px; margin-right: auto; margin-left: 8px; }
.opts { border: 0; padding: 0; margin: 12px 0 0; display: grid; gap: 8px; }
.opts legend { padding: 0; margin-bottom: 8px; }
.opt { display: flex; align-items: flex-start; gap: 12px; padding: 10px 14px; border-radius: 11px; border: 1px solid var(--border-strong); background: var(--sunken); cursor: pointer;
  transition: border-color .15s, background .15s; }
.opt:hover { border-color: var(--primary); }
.opt input { position: absolute; opacity: 0; width: 1px; height: 1px; }
.opt-key { flex: none; width: 26px; height: 26px; display: grid; place-items: center; border-radius: 7px; border: 1px solid var(--border-strong); background: var(--surface);
  font: 700 12.5px/1 var(--mono); color: var(--text-2); }
.opts[data-kind="radio"] .opt-key { border-radius: 50%; }
.opt-text { flex: 1; padding-top: 1px; }
.opt:has(input:checked) { border-color: var(--primary); background: var(--selected); }
.opt:has(input:checked) .opt-key { background: var(--primary); border-color: var(--primary); color: var(--primary-ink); }
.opt:has(input:focus-visible) { outline: 2px solid var(--focus); outline-offset: 2px; }
.qset.is-comparing .opt { cursor: default; }
.qset.is-comparing .opt:hover { border-color: var(--border-strong); }
.opt.is-correct { border-color: var(--success) !important; background: var(--success-bg) !important; }
.opt.is-correct .opt-key { background: var(--success) !important; border-color: var(--success) !important; color: #fff !important; }
.opt.is-wrong { border-color: var(--danger) !important; background: var(--danger-bg) !important; }
.opt.is-wrong .opt-key { background: var(--danger) !important; border-color: var(--danger) !important; color: #fff !important; }
.opt.is-missed { border-style: dashed !important; }
.ansinput.is-output { min-height: 64px; font: 14px/1.6 var(--mono); }
.qset.is-comparing .opts legend { display: none; }
.auto-result { margin: 0 0 10px; padding: 9px 14px; border-radius: 10px; font-weight: 650; font-size: 14.5px; border: 1px solid; }
.auto-result.ok { color: var(--success); background: var(--success-bg); border-color: color-mix(in srgb, var(--success) 50%, transparent); }
.auto-result.bad { color: var(--danger); background: var(--danger-bg); border-color: color-mix(in srgb, var(--danger) 45%, transparent); }
pre.out { margin: 0; font: 14px/1.6 var(--mono); white-space: pre-wrap; overflow-wrap: anywhere; font-variant-ligatures: none; }
pre.out.is-empty { color: var(--muted); font-style: italic; font-family: inherit; }
.cmp-explain { margin-top: 12px; }

/* ---------- progress + weak-spot practice ---------- */
.pg-sub { font-size: 13px; font-weight: 500; color: var(--muted); margin-left: 8px; letter-spacing: 0; }
.pg-stats { grid-template-columns: repeat(5, 1fr); }
.pg-stats b small { font-size: 15px; color: var(--muted); font-weight: 600; }
.pg-stats .st-y b { color: var(--success); } .pg-stats .st-p b { color: var(--watch); } .pg-stats .st-n b { color: var(--danger); }
.pg-empty { margin: 18px 0; padding: 16px 18px; border-radius: 14px; border: 1px dashed var(--border-strong); background: var(--sunken); color: var(--text-2); }
.pg-modules { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 12px; }
.pg-module, .pg-topic { padding: 14px 16px; border-radius: 14px; background: var(--surface); border: 1px solid var(--border); }
.pg-topics { display: grid; gap: 10px; }
.pg-row-top { display: flex; justify-content: space-between; align-items: baseline; gap: 12px; margin-bottom: 8px; }
.pg-row-top a { color: var(--text); font-weight: 600; }
.pg-num { font: 600 12.5px/1 var(--mono); color: var(--muted); margin-right: 4px; }
.pg-pct { font-weight: 700; font-size: 14px; font-variant-numeric: tabular-nums; white-space: nowrap; }
.pg-pct.good { color: var(--success); } .pg-pct.mid { color: var(--watch); } .pg-pct.low { color: var(--danger); } .pg-pct.none { color: var(--muted); font-weight: 500; font-size: 13px; }
.pg-bar { flex: none; } .pg-bar.good > span { background: var(--success); } .pg-bar.mid > span { background: var(--watch); } .pg-bar.low > span { background: var(--danger); }
.pg-meta { display: flex; flex-wrap: wrap; gap: 6px 14px; margin-top: 8px; font-size: 12.5px; color: var(--muted); }
.pg-practice { margin-left: auto; font-weight: 600; }
.pg-weak-list { list-style: none; padding: 0; margin: 0; display: grid; gap: 8px; }
.pg-weak-list li { display: flex; flex-wrap: wrap; align-items: baseline; gap: 6px 10px; margin: 0; padding: 10px 14px; border-radius: 11px; background: var(--surface); border: 1px solid var(--border); }
.pg-weak-list a { color: var(--text); flex: 1; min-width: 200px; }
.pg-from { font-size: 12.5px; color: var(--muted); }
.pg-badge { font-size: 11px; font-weight: 700; letter-spacing: .05em; text-transform: uppercase; padding: 2px 8px; border-radius: 6px; border: 1px solid; }
.pg-badge.n { color: var(--danger); background: var(--danger-bg); border-color: color-mix(in srgb, var(--danger) 45%, transparent); }
.pg-badge.p { color: var(--watch); background: var(--watch-bg); border-color: var(--watch-line); }
.pg-none { color: var(--muted); }
.btn.is-disabled { opacity: .55; cursor: not-allowed; box-shadow: none; }
.linkbtn { background: none; border: 0; padding: 0; color: var(--primary); font: inherit; cursor: pointer; text-decoration: underline; text-underline-offset: 3px; }
@media (max-width: 760px) { .pg-stats { grid-template-columns: repeat(2, 1fr); } .pg-stats div:first-child { grid-column: span 2; } }

/* ---------- mock exams ---------- */
.mock-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 16px; }
.mock-card { display: flex; flex-direction: column; gap: 10px; padding: 20px 22px; border-radius: 16px; background: var(--surface); border: 1px solid var(--border); box-shadow: var(--shadow-sm); }
.mock-card h3 { font-size: 18px; }
.mock-top { display: flex; justify-content: space-between; align-items: center; gap: 10px; }
.mock-kind { font-size: 11px; font-weight: 800; letter-spacing: .1em; text-transform: uppercase; padding: 4px 10px; border-radius: 20px; border: 1px solid; }
.mock-kind.quick { color: var(--concept); background: var(--concept-bg); border-color: var(--concept-line); }
.mock-kind.full { color: var(--m1); background: color-mix(in srgb, var(--m1) 12%, transparent); border-color: color-mix(in srgb, var(--m1) 40%, transparent); }
.mock-scope { font: 600 12px/1.4 var(--mono); color: var(--muted); }
.mock-stats { font-size: 13.5px; color: var(--text-2); min-height: 20px; }
.mock-go { align-self: flex-start; }
.mock-intro { margin: 18px 0; padding: 22px 24px; border-radius: 16px; background: var(--hero-glow), var(--surface); border: 1px solid var(--border-strong); box-shadow: var(--shadow); }
.mock-intro h2 { margin-top: 0; }
.mock-intro ul { margin: 6px 0 18px; }
.mockbar .timer { font: 800 20px/1 var(--mono); letter-spacing: .02em; padding: 7px 12px; border-radius: 10px; background: var(--sunken); border: 1px solid var(--border-strong); font-variant-numeric: tabular-nums; }
.mockbar .timer.warn { color: var(--watch); border-color: var(--watch-line); background: var(--watch-bg); }
.mockbar .timer.danger { color: var(--danger); border-color: color-mix(in srgb, var(--danger) 50%, transparent); background: var(--danger-bg); }
.mock-page .sf-actions { display: none; }
.mock-page .qset.is-comparing .js-edit { display: none; }
.mock-result { position: relative; margin: 18px 0; padding: 22px 24px; border-radius: 16px; background: var(--hero-glow), var(--surface); border: 1px solid var(--border-strong); box-shadow: var(--shadow); }
.mr-score { display: flex; align-items: baseline; gap: 14px; }
.mr-score b { font-size: 40px; line-height: 1; letter-spacing: -.02em; font-variant-numeric: tabular-nums; }
.mr-score span { font-size: 22px; font-weight: 700; color: var(--primary); }
.mr-lines { display: flex; flex-wrap: wrap; gap: 6px 18px; margin: 10px 0 16px; color: var(--text-2); font-size: 14.5px; }
.mr-lines span:empty { display: none; }
.mock-result.needs-marking #mr-written { color: var(--watch); font-weight: 650; }
.mock-card .module-meta { flex-wrap: wrap; } .mock-card .module-meta span { white-space: nowrap; }