/* ==========================================================================
   GoStudyPhysics — design notes (v2)

   DESIGN PLAN
   -----------
   Color (named, 6 core + 2 extra for admin/mint accents):
     --sheet #FFF8E9  warm paper cream, the desk everything sits on
     --card  #FFFFFF  a sticker cut from white paper
     --ink   #1C1C1E  near-black outline + text — stickers are die-cut, so
                       edges get a real dark line instead of a soft grey shadow
     --pen   #0071E3  Apple-blue — primary action, links, "you are here"
     --done  #1F9254  green sticker — correct / easy / complete
     --todo  #B5710A  amber sticker — in progress / medium
     --alert #D62839  red sticker   — hard / destructive
     --grape #8B3FD1  purple sticker — developer / admin only surfaces

   Type: Fredoka (rounded, chunky) carries headings and anything meant to
   read like a sticker label. Nunito carries body copy and controls — still
   rounded, but quieter, so the display face stays special. Monospace is
   unchanged: exam codes (9702/43, 13.1.1) are this app's native language.

   Layout: unchanged 3-pane shell (topbar / rail / stage) — this is a
   study tool people use for an hour at a time, not a marketing page, so
   the boldness goes into componentry (stickers, highlighter strokes,
   hard-offset shadows) rather than into reinventing the skeleton.

   Principles:
     1. Status is a sticker, not a dot. Progress, difficulty, board and
        role are all literal peel-off badges — same visual language
        everywhere, so "sticker" reads as the app's material, not a motif
        used once on the homepage.
     2. One highlighter stroke per heading, max. It marks the single most
        important word on a page (a brand name, an empty-state headline,
        a hero line on the login screen) — stacking colour there would
        read as noise, not emphasis.
     3. Colour carries meaning: blue = do this now, green = done/easy,
        amber = in progress/medium, red = hard/destructive, purple =
        you're in the developer area. Nothing is colourful just to be
        colourful.
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Fredoka:wght@500;600;700&family=Nunito:wght@400;600;700;800&display=swap');

:root {
  /* Sticker-sheet base */
  --desk: #FFD23F;          /* rail backing — the sheet stickers get peeled off of */
  --desk-edge: #EDB400;
  --sheet: #FFF8E9;         /* main working area */
  --card: #FFFFFF;          /* a sticker cut from paper */
  --card-line: #1C1C1E;     /* die-cut outline */
  --card-sunk: #FFF1D0;

  --ink: #1C1C1E;
  --ink-soft: #4B4B50;
  --ink-faint: #8A8A90;

  /* Apple-blue ink — primary accent */
  --pen: #0071E3;
  --pen-soft: #E4F0FF;
  --pen-line: #0071E3;

  /* Sticker palette — text colour + a pastel backing each */
  --done: #1F9254;
  --done-soft: #D9F5E4;
  --todo: #B5710A;
  --todo-soft: #FFECC4;
  --alert: #D62839;
  --alert-soft: #FFE1E2;
  --grape: #8B3FD1;
  --grape-soft: #F0E3FC;

  --mono: ui-monospace, "SF Mono", "Cascadia Mono", Menlo, Consolas, monospace;
  --ui: 'Nunito', -apple-system, BlinkMacSystemFont, "Segoe UI", "Helvetica Neue",
        "PingFang SC", "Microsoft YaHei", sans-serif;
  --display: 'Fredoka', var(--ui);

  --r: 16px;
  --r-sm: 10px;
  --shadow: 3px 3px 0 rgba(28,28,30,.85);
  --shadow-soft: 0 14px 30px rgba(28,28,30,.10);
}

* { box-sizing: border-box; }

html, body {
  margin: 0; height: 100%;
  font-family: var(--ui); font-size: 16.5px;
  color: var(--ink); background: var(--sheet);
  -webkit-font-smoothing: antialiased;
}
body { display: flex; flex-direction: column; overflow: hidden; }

/* ---------- highlighter marker ---------- */
.hl { position: relative; z-index: 1; white-space: nowrap; }
.hl::after {
  content: ""; position: absolute; z-index: -1;
  left: -.12em; right: -.1em; bottom: .02em; height: .42em;
  background: var(--hl, #FFE24B); opacity: .8; transform: skew(-8deg);
  border-radius: 2px;
}
.hl.pink { --hl: #FF9FCB; }
.hl.mint { --hl: #7BE0CE; }

/* ---------- stickers (badges) ---------- */
.sticker {
  display: inline-flex; align-items: center; gap: 5px;
  padding: 3px 10px; border-radius: 999px;
  border: 2px solid var(--card-line); background: var(--card);
  font-family: var(--display); font-weight: 600; font-size: 14px;
  color: var(--ink); box-shadow: 2px 2px 0 var(--card-line);
  transform: rotate(-1.5deg);
}
.sticker.r2 { transform: rotate(1.5deg); }
.sticker.dot {
  width: 11px; height: 11px; padding: 0; border-radius: 50%;
  box-shadow: 1.5px 1.5px 0 var(--card-line);
}

/* ---------- top bar ---------- */
.topbar {
  display: flex; align-items: center; gap: 18px;
  height: 54px; padding: 0 18px; flex-shrink: 0;
  background: var(--card); border-bottom: 3px solid var(--ink);
}
.brand {
  font-family: var(--display); font-size: 16.5px; font-weight: 600;
  color: #fff; background: var(--pen); padding: 5px 13px;
  border: 2.5px solid var(--ink); border-radius: 999px;
  box-shadow: var(--shadow); transform: rotate(-2deg);
  text-decoration: none; display: inline-block; flex-shrink: 0;
}
a.brand:hover { transform: rotate(-2deg) translate(-1px,-1px); box-shadow: 4px 4px 0 rgba(28,28,30,.85); }
.brand span {
  color: rgba(255,255,255,.8); font-weight: 400; margin-left: 6px;
  font-family: var(--ui); font-size: 15px;
}

.nav-search { flex: 1; max-width: 420px; }
.nav-search input {
  width: 100%; padding: 7px 15px; font-size: 14px; border-radius: 999px;
  border: 2px solid var(--card-line); background: var(--card-sunk);
}
.nav-search input:focus {
  background: var(--card); box-shadow: 2px 2px 0 var(--pen); transform: none;
}

.tabs { display: flex; gap: 8px; }
.tabs a {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 6px 15px; border-radius: 999px; font-size: 16px;
  font-family: var(--display); font-weight: 600;
  color: var(--ink); text-decoration: none; transition: .12s;
  border: 2px solid var(--card-line); background: var(--card);
}
.tabs a i { font-size: 15px; }
.tabs a:hover { transform: translateY(-1px); box-shadow: 2px 2px 0 var(--card-line); }
.tabs a.on { background: var(--pen-soft); color: var(--pen); border-color: var(--pen); }
.tabs a.admin { background: var(--grape); color: #fff; border-color: var(--card-line); }

.topstat {
  margin-left: auto; display: flex; gap: 16px; align-items: center;
  font-size: 15px; color: var(--ink-faint);
}
.topstat b {
  color: var(--ink); font-weight: 800;
  font-family: var(--mono); font-variant-numeric: tabular-nums;
}
.who {
  display: flex; align-items: center; gap: 8px;
  padding-left: 14px; border-left: 2px solid var(--card-line);
}
.who .avatar {
  width: 32px; height: 32px; border-radius: 50%; display: flex;
  align-items: center; justify-content: center; flex-shrink: 0;
  background: var(--todo-soft); color: var(--todo); border: 2px solid var(--card-line);
  font-family: var(--display); font-weight: 700; font-size: 15px;
}
.who .avatar.admin { background: var(--grape-soft); color: var(--grape); }
.who a { color: var(--ink-faint); text-decoration: none; font-size: 15px; }
.who a:hover { color: var(--alert); text-decoration: underline; }
.who .uname { font-weight: 700; color: var(--ink); font-family: var(--ui); }

/* ---------- frame ---------- */
.shell { flex: 1; display: flex; min-height: 0; }

.rail {
  width: 292px; flex-shrink: 0; display: flex; flex-direction: column;
  background: var(--desk); border-right: 3px solid var(--ink);
}
.rail-head { padding: 14px 14px 11px; border-bottom: 2px solid var(--card-line); }
.rail-title {
  font-family: var(--display); font-size: 14px; font-weight: 600; letter-spacing: .04em;
  color: var(--ink); margin-bottom: 9px;
}
.rail-scroll { flex: 1; overflow-y: auto; }
.rail-note { padding: 6px 14px 8px; font-size: 14px; color: var(--ink); opacity: .65; }

.stage { flex: 1; overflow-y: auto; background: var(--sheet); }
.stage-inner { max-width: 1080px; margin: 0 auto; padding: 22px 26px 80px; }

/* ---------- controls ---------- */
input[type=text], input[type=search], input[type=password], textarea, select {
  width: 100%; padding: 10px 13px;
  border: 2px solid var(--card-line); border-radius: var(--r-sm);
  font-family: inherit; font-size: 16px; color: var(--ink);
  background: var(--card); transition: box-shadow .12s, transform .12s;
}
input:focus, textarea:focus, select:focus {
  outline: none; box-shadow: 3px 3px 0 var(--pen);
  transform: translate(-1px,-1px);
}
textarea { resize: vertical; line-height: 1.55; }
.rail input { background: rgba(255,255,255,.75); border-color: var(--card-line); }
.rail input::placeholder { color: #7a6b3d; }

button {
  font-family: var(--display); font-size: 16px; font-weight: 600;
  padding: 10px 19px; border: 2.5px solid var(--card-line); border-radius: 999px;
  background: var(--pen); color: #fff; cursor: pointer;
  box-shadow: var(--shadow); transition: transform .1s, box-shadow .1s;
}
button:hover { background: #0864C6; transform: translate(-1px,-1px); box-shadow: 4px 4px 0 rgba(28,28,30,.85); }
button:active { transform: translate(1px,1px); box-shadow: 1px 1px 0 rgba(28,28,30,.85); }
button.ghost { background: var(--card); color: var(--ink); }
button.ghost:hover { background: var(--card-sunk); }
button.danger { background: var(--alert); }
button.danger:hover { background: #B81F2D; }
button.tiny { padding: 6px 13px; font-size: 14.5px; box-shadow: 2px 2px 0 rgba(28,28,30,.85); }
button.tiny:hover { box-shadow: 3px 3px 0 rgba(28,28,30,.85); }

.code {
  font-family: var(--mono); font-size: 15px;
  font-variant-numeric: tabular-nums; letter-spacing: -.01em;
}

/* ---------- cards ---------- */
.card {
  background: var(--card); border: 2.5px solid var(--card-line);
  border-radius: var(--r); margin-bottom: 16px;
  box-shadow: var(--shadow), var(--shadow-soft);
}
.card-head {
  display: flex; align-items: center; gap: 10px;
  padding: 11px 16px; border-bottom: 2px solid var(--card-line);
  background: var(--card-sunk); border-radius: calc(var(--r) - 3px) calc(var(--r) - 3px) 0 0;
}
.card-head h3 {
  margin: 0; font-family: var(--display); font-size: 15px; font-weight: 600;
  letter-spacing: .01em; color: var(--ink);
}
.card-body { padding: 16px; }

/* ---------- markers ---------- */
.chip {
  display: inline-flex; align-items: center; gap: 5px;
  padding: 3px 10px; border-radius: 999px; border: 2px solid var(--card-line);
  font-size: 14px; font-weight: 700; white-space: nowrap;
  font-family: var(--display); box-shadow: 1.5px 1.5px 0 var(--card-line);
}
.chip.done { background: var(--done-soft); color: var(--done); }
.chip.todo { background: var(--todo-soft); color: var(--todo); }
.chip.plain { background: var(--card-sunk); color: var(--ink-faint); border-color: var(--card-line); }

.diff {
  font-family: var(--display); font-size: 13.5px; font-weight: 700;
  padding: 3px 9px; border-radius: 999px; text-transform: uppercase; letter-spacing: .03em;
  border: 2px solid var(--card-line); box-shadow: 1.5px 1.5px 0 var(--card-line);
}
.diff.easy { background: var(--done-soft); color: var(--done); }
.diff.medium { background: var(--todo-soft); color: var(--todo); }
.diff.hard { background: var(--alert-soft); color: var(--alert); }
.diff.none { background: var(--card-sunk); color: var(--ink-faint); }

/* ---------- coverage meter ---------- */
.meter {
  width: 30px; height: 5px; border-radius: 3px; flex-shrink: 0;
  background: rgba(28,28,30,.14); overflow: hidden; display: flex;
}
.meter .fill { display: flex; height: 100%; }
.meter i { display: block; height: 100%; }
.meter .e { background: var(--done); }
.meter .m { background: var(--todo); }
.meter .h { background: var(--alert); }
.meter .u { background: #9E9584; }

/* ---------- scrollbars ---------- */
::-webkit-scrollbar { width: 11px; height: 11px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb {
  background: rgba(28,28,30,.28); border-radius: 6px;
  border: 3px solid transparent; background-clip: padding-box;
}
::-webkit-scrollbar-thumb:hover { background: rgba(28,28,30,.45); background-clip: padding-box; }

/* ---------- empty states ---------- */
.empty { padding: 64px 24px; text-align: center; color: var(--ink-faint); font-size: 16px; }
.empty b { display: block; color: var(--ink); font-family: var(--display); font-size: 18.5px; margin-bottom: 8px; }

/* ---------- result cards (study.html + subject.html) ---------- */
.q { margin-bottom: 20px; }
.q-head {
  display: flex; align-items: center; gap: 10px; flex-wrap: wrap;
  padding: 13px 18px; border-bottom: 2px solid var(--card-line);
  background: var(--card-sunk); border-radius: calc(var(--r) - 3px) calc(var(--r) - 3px) 0 0;
}
.q-src { font-family: var(--display); font-size: 14.5px; font-weight: 600; color: var(--ink); }
.q-src .dim { color: var(--ink-faint); font-weight: 400; margin: 0 3px; }
.q-head .right { margin-left: auto; }
.q-pick { display: none; align-items: center; cursor: pointer; flex-shrink: 0; }
body.selecting .q-pick { display: flex; }
.q-pick input { width: 17px; height: 17px; margin: 0; cursor: pointer; }

.export-bar {
  position: fixed; left: 50%; bottom: 22px; transform: translateX(-50%); z-index: 40;
  display: flex; align-items: center; gap: 14px; flex-wrap: wrap;
  background: var(--ink); color: #fff; border-radius: 999px; padding: 10px 12px 10px 20px;
  box-shadow: 0 6px 20px rgba(0,0,0,.3); font-family: var(--display); font-size: 13px; font-weight: 600;
  max-width: calc(100vw - 32px);
}
.export-bar button { padding: 8px 16px; font-size: 13px; }
.export-bar button.ghost { background: transparent; color: #fff; border-color: rgba(255,255,255,.4); }
.export-bar button.ghost:hover { background: rgba(255,255,255,.12); }
.export-ms-toggle { display: flex; align-items: center; gap: 6px; font-weight: 400; color: rgba(255,255,255,.85); cursor: pointer; }
.export-ms-toggle input { width: 15px; height: 15px; margin: 0; cursor: pointer; }
.export-msg { font-weight: 400; color: rgba(255,255,255,.75); }
.export-msg.ok { color: #7BE0CE; }
.export-msg.bad { color: #FF9FCB; }

.q-tags { display: flex; flex-wrap: wrap; gap: 6px; padding: 13px 18px 0; }

.q-syllabus { display: flex; flex-direction: column; gap: 6px; padding: 13px 18px 0; }
.syl-row {
  display: flex; align-items: baseline; gap: 8px; padding: 5px 12px;
  background: var(--todo-soft); border: 1.5px solid var(--card-line); border-radius: 999px;
  font-size: 12px; overflow: hidden; cursor: default;
}
.syl-row .code { font-family: var(--display); font-weight: 600; font-size: 12.5px; color: var(--todo); flex-shrink: 0; }
.syl-row .txt { color: var(--ink-soft); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

.q-imgs { display: flex; flex-wrap: wrap; gap: 12px; padding: 13px 18px 18px; }
.shot {
  border: 2.5px solid var(--card-line); border-radius: var(--r-sm);
  overflow: hidden; background: var(--card-sunk);
  flex: 1 1 320px; min-width: 220px; max-width: 100%;
}
.shot-imgs { display: flex; flex-direction: column; }
.shot-imgs img { display: block; width: 100%; height: auto; cursor: zoom-in; }
.shot-imgs img:not(:first-child) { border-top: 2px solid var(--card-line); }
.shot-tag {
  font-family: var(--display); font-size: 11px; font-weight: 600; letter-spacing: .03em;
  text-transform: uppercase; padding: 4px 10px; color: var(--ink-faint);
  border-bottom: 2px solid var(--card-line); background: var(--card);
}
.shot.ms-collapsed .shot-imgs { display: none; }
/* 选择题（P1）：没有 mark scheme 图，旁边一个窄的答案框，点了才显示字母 */
.shot.mcq-ans { flex: 0 0 150px; min-width: 130px; align-self: flex-start; }
.mcq-body { display: flex; align-items: center; justify-content: center; min-height: 96px; padding: 14px; background: var(--card); }
.mcq-body .mcq-letter { display: none; font-family: var(--display); font-size: 44px; font-weight: 700; color: var(--pen); line-height: 1; }
.mcq-body.shown button { display: none; }
.mcq-body.shown .mcq-letter { display: block; }
@media (max-width: 700px) { .shot.mcq-ans { flex: 1 1 100%; } }
.miss { padding: 28px 16px; font-size: 13px; color: var(--ink-faint); text-align: center; }

.result-note { font-size: 13.5px; color: var(--ink-faint); margin-bottom: 16px; text-align: center; }
.picked-chips { display: flex; flex-wrap: wrap; align-items: center; gap: 7px; margin-bottom: 12px; justify-content: center; }
.picked-chips-label { font-family: var(--display); font-size: 12.5px; font-weight: 600; color: var(--ink-soft); }
.picked-chip {
  display: inline-flex; align-items: center; gap: 6px; font-family: var(--mono); font-size: 12px; font-weight: 700;
  color: var(--pen); background: var(--pen-soft); border: 1.5px solid var(--pen); border-radius: 999px; padding: 3px 6px 3px 11px;
}
.picked-chip button {
  background: none; border: none; box-shadow: none; padding: 0 2px; color: inherit; font-size: 15px;
  line-height: 1; cursor: pointer; font-weight: 700;
}
.picked-chip button:hover { transform: none; box-shadow: none; opacity: .6; }
.result-note b { color: var(--ink); font-family: var(--mono); }

#lb {
  display: none; position: fixed; inset: 0; z-index: 100;
  background: rgba(28, 28, 30, .9); cursor: zoom-out;
  align-items: center; justify-content: center; flex-direction: column; gap: 12px;
}
#lb.show { display: flex; }
#lb img { max-width: 94vw; max-height: 86vh; border-radius: 8px; cursor: default; background: #fff; }
#lb .cap { font-family: var(--mono); font-size: 13px; color: #F1ECDC; }

/* ---------- difficulty segmented control (study.html + subject.html) ---------- */
.diff-seg { display: flex; border: 2px solid var(--card-line); border-radius: 999px; overflow: hidden; }
.diff-seg button {
  background: var(--card); color: var(--ink-soft); border: none; border-radius: 0;
  padding: 8px 16px; font-size: 14px; box-shadow: none;
}
.diff-seg button + button { border-left: 2px solid var(--card-line); }
.diff-seg button:hover { transform: none; box-shadow: none; background: var(--card-sunk); }
.diff-seg button.on.easy { background: var(--done); color: #fff; }
.diff-seg button.on.medium { background: var(--todo); color: #fff; }
.diff-seg button.on.hard { background: var(--alert); color: #fff; }

/* ---------- catalog cards (study.html + notes_overview.html) ---------- */
.subject-group { margin-bottom: 30px; }
.subject-group h2 {
  font-family: var(--display); font-size: 20px; font-weight: 600; margin: 0 0 4px; text-align: center;
}
.subject-group .sub { text-align: center; color: var(--ink-faint); font-size: 13.5px; margin: 0 0 24px; }
.board-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 16px; }

.board-card {
  background: var(--card); border: 2.5px solid var(--card-line); border-radius: var(--r);
  box-shadow: var(--shadow); padding: 18px 20px; color: var(--ink); text-decoration: none; display: block;
  transition: transform .1s, box-shadow .1s;
}
.board-card.locked { opacity: .55; }
a.board-card:hover { transform: translate(-1px,-1px); box-shadow: 4px 4px 0 rgba(28,28,30,.85); }
.bc-tag {
  display: inline-block; font-family: var(--display); font-size: 9px; font-weight: 700;
  letter-spacing: .03em; padding: 2px 9px; border-radius: 999px; border: 1.5px solid;
}
.bc-tag.alevel { background: var(--pen-soft); color: var(--pen); border-color: var(--pen); }
.bc-tag.igcse { background: var(--grape-soft); color: var(--grape); border-color: var(--grape); }
.bc-tag.admissions { background: var(--card-sunk); color: var(--ink-soft); border-color: var(--card-line); }
.bc-top { display: flex; align-items: flex-start; justify-content: space-between; gap: 8px; margin-top: 7px; }
.bc-name { font-family: var(--display); font-size: 13.5px; font-weight: 600; color: var(--ink); }
.bc-course { font-size: 10.5px; color: var(--ink-faint); margin-top: 1px; }
.bc-count { font-family: var(--mono); font-weight: 700; color: var(--pen); font-size: 13px; flex-shrink: 0; }
.bc-papers { display: flex; flex-wrap: wrap; gap: 4px; margin-top: 10px; }
.bc-paper {
  font-family: var(--mono); font-size: 9.5px; font-weight: 700; padding: 2px 7px;
  border-radius: 999px; border: 1.5px solid var(--card-line);
  background: var(--done-soft); color: var(--done);
}
.bc-paper.link { cursor: pointer; }
.bc-paper.link:hover { background: var(--pen); color: #fff; border-color: var(--pen); }
.bc-paper.off { background: var(--card-sunk); color: var(--ink-faint); border-style: dashed; }
.bc-soon {
  display: inline-block; margin-top: 10px; font-family: var(--display); font-size: 9.5px;
  font-weight: 600; color: var(--ink-faint); background: var(--card-sunk);
  border: 1.5px dashed var(--desk-edge); border-radius: 999px; padding: 3px 9px;
}
.bc-live {
  margin-top: 10px; font-size: 11px; color: var(--pen); font-weight: 700;
  display: flex; align-items: center; gap: 4px;
}

/* ---------- auth pages (login / register) ---------- */
.auth-wrap {
  min-height: 100vh; width: 100%; display: flex; align-items: center; justify-content: center;
  background-image:
    radial-gradient(var(--desk-edge) 2.5px, transparent 2.5px),
    radial-gradient(var(--pen-line) 2.5px, transparent 2.5px);
  background-size: 46px 46px;
  background-position: 0 0, 23px 23px;
  background-color: var(--sheet);
  padding: 24px;
}
.auth-card {
  width: 380px; max-width: 100%; background: var(--card);
  border: 3px solid var(--card-line); border-radius: 22px;
  box-shadow: 6px 6px 0 rgba(28,28,30,.85), var(--shadow-soft);
  padding: 30px 30px 26px;
}
.auth-brand {
  display: inline-flex; align-items: center; gap: 8px;
  font-family: var(--display); font-weight: 600; font-size: 17.5px; color: #fff;
  background: var(--pen); padding: 6px 14px; border: 2.5px solid var(--card-line);
  border-radius: 999px; box-shadow: 3px 3px 0 var(--card-line); transform: rotate(-2deg);
  margin-bottom: 18px;
}
.auth-title {
  font-family: var(--display); font-size: 25.5px; font-weight: 600; margin: 4px 0 6px;
}
.auth-sub { font-size: 16px; color: var(--ink-soft); margin: 0 0 20px; line-height: 1.5; }
.auth-fld { margin-bottom: 14px; }
.auth-fld label {
  display: block; font-family: var(--display); font-size: 14px; font-weight: 600;
  color: var(--ink-soft); margin-bottom: 5px;
}
.auth-card button { width: 100%; padding: 10px; font-size: 16.5px; margin-top: 4px; }
.auth-err {
  background: var(--alert-soft); color: var(--alert); border: 2px solid var(--card-line);
  border-radius: var(--r-sm); padding: 9px 12px; font-size: 15.5px; margin-bottom: 16px;
  font-weight: 700;
}
.auth-foot { margin-top: 18px; font-size: 15.5px; color: var(--ink-soft); text-align: center; }
.auth-foot a { color: var(--pen); font-weight: 700; text-decoration: none; }
.auth-foot a:hover { text-decoration: underline; }
.auth-hint {
  margin-top: 14px; font-size: 14.5px; color: var(--ink-faint);
  background: var(--card-sunk); border: 2px dashed var(--desk-edge);
  border-radius: var(--r-sm); padding: 8px 10px; line-height: 1.5;
}

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; animation: none !important; }
}

/* "← Back to the 12.1 notes" link on a subject page opened from the notes */
.from-notes {
  display: inline-flex; align-items: center; gap: 4px; margin-bottom: 12px;
  font-family: var(--display); font-size: 13px; font-weight: 600; color: var(--pen); text-decoration: none;
}
.from-notes:hover { text-decoration: underline; }