/* CAT Paper Archive — OMR answer-sheet visual language */
:root {
  --paper: #f4f6f9;
  --sheet: #ffffff;
  --ink: #17223b;
  --ink-2: #4a5570;
  --ink-3: #8390a8;
  --rule: #d9dfe8;
  --rule-soft: #e9edf3;
  --omr: #c7365f;          /* OMR-sheet rose: the one bold colour */
  --omr-soft: #fbe9ee;
  --ok: #1d7f55;
  --ok-soft: #e3f4ec;
  --bad: #b8322a;
  --bad-soft: #fbe8e6;
  --mark: #6a4bc4;
  --mark-soft: #eee9fb;
  --warn: #a86b00;
  --radius-s: 6px;
  --radius-m: 10px;
  --font-ui: "Instrument Sans", system-ui, sans-serif;
  --font-read: "Newsreader", Georgia, serif;
  --font-num: "Instrument Sans", system-ui, sans-serif;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --paper: #10151f; --sheet: #171e2b; --ink: #e7ebf3; --ink-2: #aab3c5;
    --ink-3: #748199; --rule: #2a3344; --rule-soft: #212938; --omr: #ee6d92; --omr-soft: #3a1d29;
    --ok: #4cc28f; --ok-soft: #173327; --bad: #f07a70; --bad-soft: #3a1c1a; --mark: #a78bfa; --mark-soft: #2a2242;
    --warn: #e0a53a; color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --paper: #10151f; --sheet: #171e2b; --ink: #e7ebf3; --ink-2: #aab3c5; --ink-3: #748199;
  --rule: #2a3344; --rule-soft: #212938; --omr: #ee6d92; --omr-soft: #3a1d29;
  --ok: #4cc28f; --ok-soft: #173327; --bad: #f07a70; --bad-soft: #3a1c1a; --mark: #a78bfa; --mark-soft: #2a2242;
  --warn: #e0a53a; color-scheme: dark;
}

* { box-sizing: border-box; }
html, body { margin: 0; }
body {
  background: var(--paper);
  color: var(--ink);
  font: 15px/1.5 var(--font-ui);
  -webkit-font-smoothing: antialiased;
}
button, input { font: inherit; color: inherit; }
button { cursor: pointer; }
:focus-visible { outline: 2px solid var(--omr); outline-offset: 2px; }
.num { font-variant-numeric: tabular-nums; }
.hidden { display: none !important; }
@media (prefers-reduced-motion: reduce) { * { transition: none !important; animation: none !important; } }

/* ---------- buttons ---------- */
.btn {
  border: 1px solid var(--rule); background: var(--sheet); border-radius: var(--radius-s);
  padding: 8px 14px; font-weight: 550; line-height: 1.2;
}
.btn:hover { border-color: var(--ink-3); }
.btn.primary { background: var(--ink); color: var(--sheet); border-color: var(--ink); }
.btn.primary:hover { opacity: .9; }
.btn.accent { background: var(--omr); color: #fff; border-color: var(--omr); }
.btn.ghost { border-color: transparent; background: transparent; color: var(--ink-2); }
.btn.ghost:hover { color: var(--ink); background: var(--rule-soft); }
.btn.small { padding: 5px 10px; font-size: 13px; }
.btn:disabled { opacity: .45; cursor: not-allowed; }

/* ---------- home ---------- */
.home { max-width: 1080px; margin: 0 auto; padding: 40px 20px 80px; }
.home-top { display: flex; justify-content: space-between; align-items: flex-start; gap: 16px; flex-wrap: wrap; }
.home h1 {
  font-size: clamp(34px, 5vw, 52px); line-height: 1.02; letter-spacing: -0.025em; margin: 0 0 10px; font-weight: 650;
}
.home .lede { color: var(--ink-2); max-width: 60ch; margin: 0; font-size: 16px; }
.home-stats { display: flex; gap: 28px; margin: 28px 0 8px; flex-wrap: wrap; }
.home-stats div { min-width: 90px; }
.home-stats b { display: block; font-size: 26px; font-weight: 650; letter-spacing: -0.01em; }
.home-stats span { color: var(--ink-3); font-size: 13px; }

.sheet {
  margin-top: 28px; background: var(--sheet); border: 1px solid var(--rule); border-radius: var(--radius-m);
  overflow: hidden;
}
.sheet-head, .year-row {
  display: grid; grid-template-columns: 128px 170px 1fr; align-items: center; gap: 16px; padding: 14px 20px;
}
.sheet-head { color: var(--ink-3); font-size: 12.5px; border-bottom: 1px solid var(--rule); background: var(--rule-soft); }
.year-row + .year-row { border-top: 1px dashed var(--rule); }
.year { white-space: nowrap; font-size: 24px; font-weight: 650; letter-spacing: -0.02em; }
.pattern { color: var(--ink-2); font-size: 13px; line-height: 1.35; }
.slots { display: flex; gap: 12px; flex-wrap: wrap; }
.slot {
  display: flex; align-items: center; gap: 12px; padding: 8px 12px 8px 8px; border: 1px solid var(--rule);
  border-radius: 999px; background: var(--sheet); min-width: 200px; text-align: left;
}
.slot:hover { border-color: var(--omr); }
.slot.missing { opacity: .5; cursor: default; }
.slot.missing:hover { border-color: var(--rule); }
.bubble {
  width: 34px; height: 34px; border-radius: 50%; border: 1.5px solid var(--omr); color: var(--omr);
  display: grid; place-items: center; font-weight: 650; font-size: 14px; flex: none;
}
.slot.done .bubble { background: var(--omr); color: #fff; }
.slot-meta { display: flex; flex-direction: column; line-height: 1.25; }
.slot-meta b { font-weight: 600; font-size: 14px; }
.slot-meta span { font-size: 12.5px; color: var(--ink-3); }

@media (max-width: 720px) {
  .sheet-head { display: none; }
  .year-row { grid-template-columns: 1fr; gap: 8px; }
  .slot { min-width: 0; flex: 1 1 100%; }
}

.foot-note { color: var(--ink-3); font-size: 13px; margin-top: 18px; max-width: 75ch; }
.foot-note a { color: var(--ink-2); font-weight: 600; }

/* ---------- in progress (unfinished sessions, one per paper) ---------- */
a.btn { display: inline-block; text-decoration: none; color: inherit; }
a.btn.primary { color: var(--sheet); }
.inprog { border-color: var(--omr); }
.inprog-h { margin: 0; padding: 12px 20px; font-size: 13px; font-weight: 650; letter-spacing: .04em; text-transform: uppercase; color: var(--omr); background: var(--omr-soft); }
.inprog-h span { display: inline-grid; place-items: center; min-width: 20px; height: 20px; padding: 0 6px; margin-left: 4px; border-radius: 999px; background: var(--omr); color: #fff; font-size: 12px; letter-spacing: 0; }
.inprog-row { display: flex; align-items: center; justify-content: space-between; gap: 12px 16px; padding: 14px 20px; flex-wrap: wrap; }
.inprog-row + .inprog-row { border-top: 1px dashed var(--rule); }
.inprog-txt { display: flex; flex-direction: column; gap: 2px; min-width: 0; flex: 1 1 260px; }
.inprog-txt b { font-weight: 600; }
.inprog-txt span { color: var(--ink-3); font-size: 13px; }
.inprog-bar { display: block; height: 4px; border-radius: 99px; background: var(--rule-soft); margin-top: 6px; max-width: 320px; overflow: hidden; }
.inprog-bar i { display: block; height: 100%; background: var(--omr); border-radius: 99px; }
.inprog-act { display: flex; gap: 8px; align-items: center; }
.resume-row { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-top: 18px; padding: 12px 14px; border: 1px solid var(--omr); background: var(--omr-soft); border-radius: var(--radius-m); }
.resume-row div { display: flex; flex-direction: column; min-width: 0; }
.resume-row span { color: var(--ink-2); font-size: 13px; }

/* ---------- modal ---------- */
.scrim { position: fixed; inset: 0; background: rgba(15, 20, 32, .45); display: grid; place-items: center; z-index: 50; padding: 16px; }
.modal {
  background: var(--sheet); border-radius: var(--radius-m); max-width: 620px; width: 100%; padding: 26px;
  border: 1px solid var(--rule); max-height: 92vh; overflow: auto;
}
.modal h2 { margin: 0 0 4px; font-size: 24px; letter-spacing: -0.015em; }
.modal .sub { color: var(--ink-2); margin: 0 0 18px; }
.modes { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
@media (max-width: 560px) { .modes { grid-template-columns: 1fr; } }
.mode {
  text-align: left; border: 1.5px solid var(--rule); border-radius: var(--radius-m); padding: 16px; background: var(--sheet);
}
.mode:hover { border-color: var(--ink-3); }
.mode[aria-pressed="true"] { border-color: var(--omr); background: var(--omr-soft); }
.mode b { display: block; font-size: 16px; margin-bottom: 4px; }
.mode span { color: var(--ink-2); font-size: 13.5px; }
.field-label { font-size: 13px; color: var(--ink-2); margin: 18px 0 8px; font-weight: 550; }
.chips { display: flex; gap: 8px; flex-wrap: wrap; }
.chip {
  border: 1px solid var(--rule); border-radius: 999px; padding: 6px 12px; background: var(--sheet); font-size: 13.5px;
}
.chip[aria-pressed="true"] { border-color: var(--ink); background: var(--ink); color: var(--sheet); }
.modal-actions { display: flex; justify-content: space-between; align-items: center; gap: 10px; margin-top: 22px; flex-wrap: wrap; }
.history { margin-top: 18px; border-top: 1px solid var(--rule); padding-top: 14px; }
.history-row { display: flex; justify-content: space-between; align-items: center; padding: 6px 0; font-size: 14px; gap: 10px; }
.history-row span { color: var(--ink-3); }

/* ---------- test shell ---------- */
.shell { display: grid; grid-template-rows: auto auto 1fr auto; height: 100vh; height: 100dvh; }
.topbar {
  display: flex; align-items: center; gap: 14px; padding: 10px 18px; background: var(--ink); color: var(--sheet);
}
.topbar .title { font-weight: 600; }
.topbar .mode-tag { font-size: 12px; padding: 2px 8px; border-radius: 999px; border: 1px solid rgba(255,255,255,.35); }
.topbar .spacer { flex: 1; }
.timer { font-size: 20px; font-weight: 650; letter-spacing: .02em; }
.timer.low { color: #ffb4c6; }
.topbar .btn.ghost { color: rgba(255,255,255,.8); }
.topbar .btn.ghost:hover { background: rgba(255,255,255,.1); color: #fff; }
:root[data-theme="dark"] .topbar, :root:not([data-theme="light"]) .topbar { }
.sectionbar { display: flex; gap: 0; border-bottom: 1px solid var(--rule); background: var(--sheet); padding: 0 18px; overflow-x: auto; }
.sec-tab {
  border: 0; background: none; padding: 11px 16px; font-weight: 550; color: var(--ink-3); border-bottom: 2.5px solid transparent;
  white-space: nowrap;
}
.sec-tab.active { color: var(--ink); border-bottom-color: var(--omr); }
.sec-tab:disabled { cursor: not-allowed; }
.sec-tab .lock { font-size: 12px; margin-left: 4px; }

.workspace { display: grid; grid-template-columns: minmax(0, 1fr) 290px; min-height: 0; }
.stage { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); min-height: 0; }
.stage.solo { grid-template-columns: minmax(0, 1fr); }
.pane { overflow: auto; padding: 22px 26px 40px; min-height: 0; }
.pane.context { border-right: 1px solid var(--rule); background: var(--sheet); }
.context h3 { margin: 0 0 12px; font-size: 16px; }
.context .body { font-family: var(--font-read); font-size: 17px; line-height: 1.62; max-width: 68ch; }
.context .body p { margin: 0 0 1em; }
.set-body { font-family: var(--font-ui) !important; font-size: 15px !important; line-height: 1.55 !important; }
table.md { border-collapse: collapse; margin: 12px 0 16px; font-family: var(--font-ui); font-size: 14px; }
table.md th, table.md td { border: 1px solid var(--rule); padding: 5px 10px; text-align: left; }
table.md th { background: var(--rule-soft); font-weight: 600; }
.pane.question { max-width: 780px; }
.q-head { display: flex; justify-content: space-between; align-items: center; gap: 10px; color: var(--ink-3); font-size: 13px; margin-bottom: 10px; flex-wrap: wrap; }
.q-no { color: var(--ink); font-weight: 650; font-size: 15px; }
.q-type { border: 1px solid var(--rule); border-radius: 999px; padding: 1px 8px; font-size: 12px; }
.q-text { font-size: 16.5px; line-height: 1.6; margin-bottom: 18px; }
.q-text p { margin: 0 0 .8em; }
.options { display: flex; flex-direction: column; gap: 10px; }
.opt {
  display: grid; grid-template-columns: 30px 1fr; gap: 12px; align-items: start; text-align: left;
  border: 1px solid var(--rule); border-radius: var(--radius-m); padding: 11px 14px; background: var(--sheet); line-height: 1.5;
}
.opt:hover { border-color: var(--ink-3); }
.opt .ob {
  width: 26px; height: 26px; border-radius: 50%; border: 1.5px solid var(--ink-3); display: grid; place-items: center;
  font-size: 12.5px; font-weight: 650; color: var(--ink-2); margin-top: -1px;
}
.opt.sel { border-color: var(--ink); }
.opt.sel .ob { background: var(--ink); border-color: var(--ink); color: var(--sheet); }
.opt.right { border-color: var(--ok); background: var(--ok-soft); }
.opt.right .ob { background: var(--ok); border-color: var(--ok); color: #fff; }
.opt.wrong { border-color: var(--bad); background: var(--bad-soft); }
.opt.wrong .ob { background: var(--bad); border-color: var(--bad); color: #fff; }
.opt:disabled { cursor: default; }
.tita { display: flex; flex-direction: column; gap: 10px; max-width: 280px; }
.tita input {
  font-size: 20px; padding: 10px 12px; border: 1.5px solid var(--rule); border-radius: var(--radius-s); background: var(--sheet);
  font-variant-numeric: tabular-nums;
}
.tita input.right { border-color: var(--ok); background: var(--ok-soft); }
.tita input.wrong { border-color: var(--bad); background: var(--bad-soft); }
.keypad { display: grid; grid-template-columns: repeat(3, 1fr); gap: 6px; }
.keypad button { padding: 9px 0; border: 1px solid var(--rule); border-radius: var(--radius-s); background: var(--sheet); font-weight: 600; }
.keypad button:hover { border-color: var(--ink-3); }
.tita-hint { font-size: 12.5px; color: var(--ink-3); }

.solution {
  margin-top: 22px; border-left: 3px solid var(--ok); background: var(--ok-soft); padding: 14px 16px; border-radius: 0 var(--radius-s) var(--radius-s) 0;
}
.solution.miss { border-left-color: var(--bad); background: var(--bad-soft); }
.solution .verdict { font-weight: 650; margin-bottom: 6px; }
.solution .ans { font-size: 14px; color: var(--ink-2); margin-bottom: 8px; }
.solution .expl { line-height: 1.6; }
.solution .expl p { margin: 0 0 .7em; }
.tags { display: flex; gap: 6px; margin-top: 10px; flex-wrap: wrap; }
.tag { font-size: 12px; border: 1px solid var(--rule); background: var(--sheet); border-radius: 999px; padding: 1px 8px; color: var(--ink-2); }

/* palette */
.rail { border-left: 1px solid var(--rule); background: var(--sheet); display: flex; flex-direction: column; min-height: 0; }
.rail-head { padding: 14px 16px 8px; font-weight: 600; font-size: 14px; }
.legend { display: grid; grid-template-columns: 1fr 1fr; gap: 6px 10px; padding: 0 16px 12px; font-size: 12px; color: var(--ink-2); border-bottom: 1px solid var(--rule); }
.legend span { display: flex; align-items: center; gap: 6px; }
.legend i { width: 14px; height: 14px; border-radius: 50%; display: inline-block; flex: none; }
.grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 8px; padding: 14px 16px; overflow: auto; align-content: start; }
.pb {
  aspect-ratio: 1; border-radius: 50%; border: 1.5px solid var(--rule); background: var(--sheet); font-size: 13px; font-weight: 600;
  display: grid; place-items: center; color: var(--ink-2); position: relative; padding: 0;
}
.pb.nv { border-color: var(--rule); color: var(--ink-3); }
.pb.na { border-color: var(--omr); color: var(--omr); }
.pb.an { background: var(--ok); border-color: var(--ok); color: #fff; }
.pb.mk { background: var(--mark); border-color: var(--mark); color: #fff; }
.pb.am { background: var(--mark); border-color: var(--mark); color: #fff; }
.pb.am::after { content: ""; position: absolute; right: -1px; bottom: -1px; width: 10px; height: 10px; border-radius: 50%; background: var(--ok); border: 2px solid var(--sheet); }
.pb.cur { outline: 2px solid var(--ink); outline-offset: 2px; }
.pb.r { background: var(--ok); border-color: var(--ok); color: #fff; }
.pb.w { background: var(--bad); border-color: var(--bad); color: #fff; }
.rail-foot { margin-top: auto; padding: 12px 16px; border-top: 1px solid var(--rule); display: flex; flex-direction: column; gap: 8px; }
.rail-count { font-size: 12.5px; color: var(--ink-2); }

.actionbar {
  display: flex; gap: 8px; padding: 10px 18px; border-top: 1px solid var(--rule); background: var(--sheet); flex-wrap: wrap; align-items: center;
}
.actionbar .spacer { flex: 1; }

@media (max-width: 980px) {
  .workspace { grid-template-columns: 1fr; }
  .rail { display: none; }
  .rail.open { display: flex; position: fixed; right: 0; top: 0; bottom: 0; width: min(320px, 88vw); z-index: 40; box-shadow: -8px 0 30px rgba(0,0,0,.18); }
  .stage { grid-template-columns: 1fr; overflow: auto; }
  .pane { overflow: visible; }
  .pane.context { border-right: 0; border-bottom: 1px solid var(--rule); max-height: none; }
}
.only-narrow { display: none; }
@media (max-width: 980px) { .only-narrow { display: inline-flex; } }

/* calculator */
.calc {
  position: fixed; right: 310px; top: 110px; width: 240px; background: var(--sheet); border: 1px solid var(--rule);
  border-radius: var(--radius-m); padding: 10px; z-index: 45; box-shadow: 0 10px 30px rgba(0,0,0,.15);
}
@media (max-width: 980px) { .calc { right: 12px; } }
.calc-display { font-size: 22px; text-align: right; padding: 8px 10px; border: 1px solid var(--rule); border-radius: var(--radius-s); margin-bottom: 8px; overflow: hidden; font-variant-numeric: tabular-nums; }
.calc-keys { display: grid; grid-template-columns: repeat(4, 1fr); gap: 5px; }
.calc-keys button { padding: 8px 0; border: 1px solid var(--rule); border-radius: var(--radius-s); background: var(--paper); font-weight: 600; }
.calc-head { display: flex; justify-content: space-between; align-items: center; font-size: 13px; color: var(--ink-2); margin-bottom: 6px; }

/* ---------- results ---------- */
.results { max-width: 1080px; margin: 0 auto; padding: 32px 20px 80px; }
.res-top { display: flex; justify-content: space-between; align-items: flex-start; gap: 16px; flex-wrap: wrap; }
.res-top h1 { margin: 0; font-size: 30px; letter-spacing: -0.02em; }
.res-top p { margin: 4px 0 0; color: var(--ink-2); }
.scoreline { display: flex; align-items: baseline; gap: 12px; margin: 26px 0 6px; flex-wrap: wrap; }
.scoreline .big { font-size: 64px; font-weight: 700; letter-spacing: -0.03em; line-height: 1; }
.scoreline .of { color: var(--ink-3); font-size: 18px; }
.sec-table { width: 100%; border-collapse: collapse; background: var(--sheet); border: 1px solid var(--rule); border-radius: var(--radius-m); overflow: hidden; margin-top: 18px; font-size: 14.5px; }
.sec-table th, .sec-table td { padding: 11px 14px; text-align: right; border-bottom: 1px solid var(--rule-soft); }
.sec-table th:first-child, .sec-table td:first-child { text-align: left; }
.sec-table th { font-size: 12.5px; color: var(--ink-3); font-weight: 550; background: var(--rule-soft); }
.sec-table tr:last-child td { border-bottom: 0; font-weight: 650; }
.table-wrap { overflow-x: auto; }
.bar { height: 6px; border-radius: 3px; background: var(--rule-soft); overflow: hidden; display: flex; width: 120px; margin-left: auto; }
.bar i { display: block; height: 100%; }
.review-head { display: flex; justify-content: space-between; align-items: center; gap: 12px; margin: 38px 0 12px; flex-wrap: wrap; }
.review-head h2 { margin: 0; font-size: 20px; }
.rev-item { background: var(--sheet); border: 1px solid var(--rule); border-radius: var(--radius-m); margin-bottom: 10px; }
.rev-summary {
  display: grid; grid-template-columns: 34px 1fr auto; gap: 12px; align-items: center; padding: 12px 14px; width: 100%;
  border: 0; background: none; text-align: left;
}
.rev-summary .pb { width: 30px; }
.rev-summary .snip { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; color: var(--ink-2); font-size: 14px; }
.rev-summary .meta { font-size: 12.5px; color: var(--ink-3); white-space: nowrap; }
.rev-body { padding: 0 16px 16px 60px; }
@media (max-width: 640px) { .rev-body { padding: 0 14px 14px; } .rev-summary .meta { display: none; } }
.rev-body details { margin-bottom: 12px; }
.rev-body summary { cursor: pointer; color: var(--ink-2); font-size: 13.5px; }
.rev-body .ctx { font-family: var(--font-read); font-size: 15.5px; line-height: 1.6; margin-top: 8px; max-height: 360px; overflow: auto; padding: 10px 12px; background: var(--paper); border-radius: var(--radius-s); }
.rev-body .ctx p { margin: 0 0 .8em; }

.toast { position: fixed; bottom: 22px; left: 50%; transform: translateX(-50%); background: var(--ink); color: var(--sheet); padding: 10px 16px; border-radius: var(--radius-s); z-index: 60; font-size: 14px; }

a.btn { text-decoration: none; display: inline-flex; align-items: center; }
.calc-head { cursor: move; user-select: none; }
@media (max-width: 640px) {
  .topbar { gap: 6px; padding: 8px 10px; }
  .topbar .mode-tag { display: none; }
  .topbar .title { font-size: 14px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; min-width: 0; }
  .timer { font-size: 17px; }
  .topbar .btn.small { padding: 5px 6px; }
  .pane { padding: 16px 16px 32px; }
  .actionbar { padding: 8px 10px; gap: 6px; }
  .actionbar .btn { padding: 8px 10px; font-size: 14px; }
}