/* FLC dMAT MasterBook · interactive edition and test-screen practice.
   Every colour comes from the theme variables, so each reader theme is one block.
   Default ("book") is the dMAT deep plum; the other four match the other MasterBooks. */
html, html[data-theme="book"] {
  --t-accent: #8a1f62; --t-deep: #4e0f37; --t-tint: #f8edf3; --t-tint2: #f0dbe7; --t-soft: #d4a3c0;
  --t-paper: #ffffff; --t-ground: #f7f2f5; --t-ink: #1f1a24; --t-mute: #6a5f6b; --t-line: #e7d9e2;
  --t-ok: #157a4a; --t-ok-tint: #e3f4ea; --t-bad: #b42335; --t-bad-tint: #fbe6e9; --t-gold: #c9a24a;
}
html[data-theme="navy"] {
  --t-accent: #0b5ea8; --t-deep: #0b2a4a; --t-tint: #eaf2fb; --t-tint2: #d6e6f6; --t-soft: #9db9d8;
  --t-paper: #ffffff; --t-ground: #eef3f8; --t-ink: #1c2733; --t-mute: #5b6b7b; --t-line: #d5dde6;
  --t-ok: #157a4a; --t-ok-tint: #e3f4ea; --t-bad: #c2161f; --t-bad-tint: #fbe5e6; --t-gold: #c9a24a;
}
html[data-theme="paper"] {
  --t-accent: #8a5a24; --t-deep: #5a3a17; --t-tint: #f6ecd9; --t-tint2: #eedcbc; --t-soft: #c9ab7e;
  --t-paper: #fffaf0; --t-ground: #f3ead8; --t-ink: #2f2a22; --t-mute: #6f6455; --t-line: #e6d9c2;
  --t-ok: #3f7a2a; --t-ok-tint: #e7f0dc; --t-bad: #a8322a; --t-bad-tint: #f6e0d8; --t-gold: #a87a2a;
}
html[data-theme="night"] {
  --t-accent: #e08ac0; --t-deep: #f5d6ea; --t-tint: #2a1c26; --t-tint2: #3a2534; --t-soft: #6e4862;
  --t-paper: #1b1419; --t-ground: #120d11; --t-ink: #efe6ec; --t-mute: #b7a6b2; --t-line: #3a2c36;
  --t-ok: #5fd39a; --t-ok-tint: #173527; --t-bad: #ff8a95; --t-bad-tint: #3b1d22; --t-gold: #e3c271;
}
html[data-theme="contrast"] {
  --t-accent: #0040a8; --t-deep: #000000; --t-tint: #fff6bf; --t-tint2: #ffe97a; --t-soft: #000000;
  --t-paper: #ffffff; --t-ground: #ffffff; --t-ink: #000000; --t-mute: #1a1a1a; --t-line: #000000;
  --t-ok: #00602a; --t-ok-tint: #d9f7e2; --t-bad: #b00000; --t-bad-tint: #ffe0e0; --t-gold: #7a5a00;
}
html { --fs: 15.5px; }
html[data-size="s"] { --fs: 14px; } html[data-size="l"] { --fs: 17.5px; } html[data-size="xl"] { --fs: 20px; }
:root {
  --sans: "Inter", system-ui, -apple-system, "Segoe UI", sans-serif;
  --serif: "Source Serif 4", Georgia, "Times New Roman", serif;
  --sym-ink: #1f1a24; --sym-grey: #9a9aa2; --sym-white: #ffffff; --grid: #3b3540;
}
html[data-theme="night"] { --on-accent: #1b1419; --sym-ink: #f1e8ee; --sym-grey: #8b8590; --sym-white: #1b1419; --grid: #b7a6b2; }

* { box-sizing: border-box; }
[hidden] { display: none !important; }
html { -webkit-text-size-adjust: 100%; }
body { margin: 0; background: var(--t-ground); color: var(--t-ink); font: 400 var(--fs)/1.6 var(--sans);
  padding: 0 max(16px, env(safe-area-inset-right)) 64px max(16px, env(safe-area-inset-left)); }
a { color: var(--t-accent); }
button { font: inherit; cursor: pointer; color: inherit; }
button:focus-visible, a:focus-visible, input:focus-visible { outline: 3px solid var(--t-accent); outline-offset: 2px; }
.page { max-width: 900px; margin: 0 auto; }
.wide { max-width: 1180px; }

/* masthead and sticky bar */
.mast { display: flex; align-items: center; gap: 14px; padding: 20px 0 12px; position: relative; flex-wrap: wrap; }
.mast img { height: 34px; width: auto; background: #fff; border-radius: 6px; padding: 4px 8px; }
.mast .ed { font: 700 12.5px/1.2 var(--sans); letter-spacing: .12em; text-transform: uppercase; color: var(--t-mute); }
.mast .sp { flex: 1; }
.bar { position: sticky; top: 0; z-index: 30; display: flex; align-items: center; gap: 10px; flex-wrap: wrap;
  margin: 0 -16px 22px; padding: 10px 16px; background: var(--t-deep); color: #fff; box-shadow: 0 8px 24px -14px rgba(0,0,0,.5); }
html[data-theme="night"] .bar { background: #2a1724; }
.bar a.back { color: #fff; text-decoration: none; font: 600 14px var(--sans); opacity: .9; }
.bar .ttl { font: 700 14.5px/1.25 var(--sans); flex: 1; min-width: 150px; }
.bar .ttl small { display: block; font-weight: 500; font-size: 12px; opacity: .78; }
.btn { display: inline-flex; align-items: center; gap: 6px; border: 1.5px solid transparent; border-radius: 10px;
  padding: 8px 14px; font: 650 14px/1.2 var(--sans); background: var(--t-accent); color: var(--on-accent, #fff); text-decoration: none; }
.btn.ghost { background: transparent; border-color: var(--t-line); color: var(--t-accent); }
.bar .btn.ghost, .mast .btn.ghost { border-color: rgba(255,255,255,.45); color: #fff; }
.mast .btn.ghost { border-color: var(--t-line); color: var(--t-accent); }
.btn.soft { background: var(--t-tint); color: var(--t-deep); border-color: var(--t-tint2); }
.btn:disabled { opacity: .55; cursor: default; }
.btn svg { width: 17px; height: 17px; }
.seg { display: inline-flex; background: rgba(255,255,255,.14); border-radius: 10px; padding: 3px; }
.seg button { border: 0; background: transparent; color: #fff; font: 650 13px var(--sans); padding: 6px 12px; border-radius: 8px; }
.seg button[aria-pressed="true"] { background: #fff; color: #4e0f37; }

/* theme picker */
.th-pop { position: absolute; right: 0; top: calc(100% + 6px); z-index: 60; width: min(330px, calc(100vw - 32px)); background: var(--t-paper);
  color: var(--t-ink); border: 1px solid var(--t-line); border-radius: 14px; padding: 14px; box-shadow: 0 24px 50px -18px rgba(0,0,0,.45); }
.th-pop h4 { margin: 4px 0 8px; font: 700 11px var(--sans); letter-spacing: .14em; text-transform: uppercase; color: var(--t-mute); }
.th-themes { display: grid; gap: 6px; }
.th-theme { display: grid; grid-template-columns: auto 1fr; column-gap: 10px; text-align: left; border: 1.5px solid var(--t-line);
  border-radius: 10px; padding: 8px 10px; background: var(--t-paper); font: 650 13.5px/1.25 var(--sans); }
.th-theme small { grid-column: 2; font-weight: 400; color: var(--t-mute); font-size: 12px; }
.th-theme .sw { grid-row: span 2; display: flex; align-self: center; }
.th-theme .sw i { width: 12px; height: 26px; display: block; } .th-theme .sw i:first-child { border-radius: 5px 0 0 5px; } .th-theme .sw i:last-child { border-radius: 0 5px 5px 0; border: 1px solid #ddd; border-left: 0; }
.th-theme[aria-pressed="true"] { border-color: var(--t-accent); background: var(--t-tint); }
.th-row { display: flex; gap: 6px; } .th-row button { flex: 1; border: 1.5px solid var(--t-line); border-radius: 9px; padding: 6px; background: var(--t-paper); font-weight: 700; }
.th-row button[aria-pressed="true"] { border-color: var(--t-accent); background: var(--t-tint); }
.th-note { font-size: 12px; color: var(--t-mute); margin: 10px 0 0; }

/* cover */
.cover { position: relative; display: grid; grid-template-columns: 1.25fr .9fr; min-height: 420px; border-radius: 22px; overflow: hidden;
  background: radial-gradient(120% 90% at 0% 0%, #a3317a 0%, transparent 55%), linear-gradient(140deg, #3d0a2b 0%, #6a1550 55%, #8a1f62 100%);
  color: #fff; box-shadow: 0 30px 60px -30px rgba(78,15,55,.7); margin-bottom: 26px; }
html[data-theme="navy"] .cover, html[data-theme="contrast"] .cover { background: linear-gradient(140deg, #071b31, #0b2a4a 55%, #0b5ea8); }
html[data-theme="paper"] .cover { background: linear-gradient(140deg, #3b250e, #5a3a17 55%, #8a5a24); }
.cover::after { content: ""; position: absolute; inset: 0; pointer-events: none;
  background-image: linear-gradient(rgba(255,255,255,.06) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,.06) 1px, transparent 1px);
  background-size: 34px 34px; mask-image: linear-gradient(90deg, #000 0%, transparent 70%); }
.cover .txt { position: relative; z-index: 1; padding: clamp(24px, 5vw, 46px); display: flex; flex-direction: column; gap: 10px; }
.cover .logo { height: 30px; width: auto; align-self: flex-start; margin-bottom: 8px; }
.cover .ser { font: 700 11.5px var(--sans); letter-spacing: .2em; text-transform: uppercase; color: #f3c9e1; }
.cover h1 { margin: 4px 0 0; font: 800 clamp(40px, 7vw, 66px)/.95 var(--sans); letter-spacing: -.03em; }
.cover h1 em { display: block; font: italic 600 clamp(28px, 4.6vw, 42px)/1.1 var(--serif); letter-spacing: 0; color: #f3c9e1; }
.cover .line { font: 600 17px/1.4 var(--sans); margin: 8px 0 0; max-width: 460px; }
.cover .sub { font-size: 14.5px; opacity: .85; margin: 0; }
.cover .rel { display: inline-flex; align-self: flex-start; gap: 8px; align-items: center; margin-top: 6px; padding: 6px 12px; border-radius: 999px;
  background: rgba(255,255,255,.13); font: 650 12.5px var(--sans); }
.cover .auth { margin-top: auto; padding-top: 18px; font-size: 13.5px; opacity: .92; }
.cover .auth b { display: block; font-size: 16px; }
.cover .cta { margin-top: 14px; align-self: flex-start; background: #fff; color: var(--t-deep); }
.cover .ph { position: relative; z-index: 1; display: flex; align-items: flex-end; justify-content: center; overflow: hidden; }
.cover .ph img { width: 100%; max-width: 380px; height: auto; display: block; filter: drop-shadow(0 20px 30px rgba(0,0,0,.35)); }
.cover .motif { position: absolute; right: 18px; top: 18px; z-index: 2; display: grid; grid-template-columns: repeat(5, 18px); gap: 3px; opacity: .55; }
.cover .motif i { height: 18px; border: 1px solid rgba(255,255,255,.55); border-radius: 3px; font: 700 10px/16px var(--sans); text-align: center; font-style: normal; }
@media (max-width: 720px) { .cover { grid-template-columns: 1fr; } .cover .ph { max-height: 300px; } .cover .ph img { max-width: 260px; } .cover .motif { display: none; } }

/* index cards */
.lead { font: 400 17px/1.6 var(--sans); color: var(--t-mute); max-width: 680px; }
.sec-h { font: 800 13px var(--sans); letter-spacing: .16em; text-transform: uppercase; color: var(--t-accent); margin: 34px 0 12px; }
.grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 14px; }
.card { background: var(--t-paper); border: 1px solid var(--t-line); border-radius: 16px; padding: 16px 18px 18px; position: relative; overflow: hidden; }
.card::before { content: ""; position: absolute; inset: 0 0 auto; height: 4px; background: linear-gradient(90deg, var(--t-deep), var(--t-accent)); }
.card h3 { margin: 4px 0 4px; font: 800 20px/1.2 var(--sans); color: var(--t-deep); }
.card .kick { font: 700 11px var(--sans); letter-spacing: .14em; text-transform: uppercase; color: var(--t-accent); }
.card p { margin: 0 0 12px; color: var(--t-mute); font-size: 14px; }
.links { display: grid; gap: 6px; }
.links a { display: flex; justify-content: space-between; gap: 10px; align-items: baseline; text-decoration: none; border: 1.5px solid var(--t-line);
  border-radius: 10px; padding: 8px 12px; color: var(--t-deep); background: var(--t-paper); }
.links a:hover { border-color: var(--t-accent); background: var(--t-tint); }
.links b { font: 700 14.5px/1.25 var(--sans); } .links small { color: var(--t-mute); font-size: 12px; text-align: right; }
.links a .lv { display: inline-grid; place-items: center; width: 22px; height: 22px; border-radius: 6px; background: var(--t-tint); color: var(--t-accent); font: 800 12px var(--sans); margin-right: 8px; }
.note { margin-top: 34px; font-size: 12.5px; color: var(--t-mute); border-top: 1px solid var(--t-line); padding-top: 14px; }
.badge { display: inline-block; font: 700 10.5px var(--sans); letter-spacing: .12em; text-transform: uppercase; padding: 3px 8px; border-radius: 6px; }
.badge.off { background: #e9f1fb; color: #0b4f8f; } .badge.flc { background: var(--t-tint); color: var(--t-accent); }

/* book pages */
.unit-h { background: linear-gradient(135deg, var(--t-deep), var(--t-accent)); color: #fff; border-radius: 18px; padding: 24px clamp(18px, 4vw, 32px); margin-bottom: 20px; }
.unit-h .kick { font: 700 11.5px var(--sans); letter-spacing: .18em; text-transform: uppercase; opacity: .8; }
.unit-h h1 { margin: 6px 0 6px; font: 800 clamp(26px, 4.5vw, 36px)/1.1 var(--sans); letter-spacing: -.02em; }
.unit-h p { margin: 0; opacity: .9; max-width: 640px; }
.unit-h .meta { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 14px; }
.unit-h .meta span { background: rgba(255,255,255,.15); border-radius: 999px; padding: 4px 11px; font: 600 12.5px var(--sans); }
.sheet { background: var(--t-paper); border: 1px solid var(--t-line); border-radius: 16px; padding: clamp(18px, 4vw, 30px); margin-bottom: 18px; }
.sheet h2 { font: 800 22px/1.25 var(--sans); color: var(--t-deep); margin: 0 0 10px; display: flex; gap: 12px; align-items: baseline; }
.sheet h2 .no { font: 800 13px var(--sans); color: var(--t-accent); letter-spacing: .1em; }
.sheet h3 { font: 750 17px/1.3 var(--sans); color: var(--t-deep); margin: 22px 0 8px; }
.sheet p { margin: 0 0 12px; font-family: var(--serif); font-size: calc(var(--fs) + 1.5px); line-height: 1.65; }
.sheet ol.method { margin: 6px 0 14px; padding-left: 22px; font-family: var(--serif); font-size: calc(var(--fs) + 1px); }
.box { border-radius: 12px; padding: 12px 14px 12px 16px; margin: 12px 0; border-left: 5px solid; font-size: calc(var(--fs) - .5px); }
.box b { display: block; font: 800 11px var(--sans); letter-spacing: .16em; margin-bottom: 3px; }
.box.RULE { background: var(--t-tint); border-color: var(--t-accent); } .box.RULE b { color: var(--t-accent); }
.box.TIP { background: #e8f4ee; border-color: #1f8a5b; } .box.TIP b { color: #157a4a; }
.box.TRAP { background: #fdf0e4; border-color: #d0732a; } .box.TRAP b { color: #a8541a; }
.box.TRY { background: var(--t-ground); border-color: var(--t-soft); } .box.TRY b { color: var(--t-mute); }
html[data-theme="night"] .box.TIP { background: #13261d; } html[data-theme="night"] .box.TRAP { background: #2e1d10; }
.toc { display: flex; flex-wrap: wrap; gap: 6px; margin: 0 0 18px; }
.toc a { font: 600 13px var(--sans); text-decoration: none; padding: 6px 11px; border-radius: 999px; background: var(--t-paper); border: 1px solid var(--t-line); color: var(--t-deep); }

/* question cards */
.qset-h { display: flex; align-items: center; justify-content: space-between; gap: 10px; flex-wrap: wrap; margin: 6px 0 12px; }
.qset-h .score { font: 700 14px var(--sans); color: var(--t-deep); }
.q { border: 1px solid var(--t-line); border-radius: 14px; padding: 14px; margin: 0 0 14px; background: var(--t-paper); }
.q-top { display: flex; align-items: center; gap: 10px; margin-bottom: 10px; }
.q-no { display: inline-grid; place-items: center; min-width: 30px; height: 30px; border-radius: 8px; background: var(--t-deep); color: var(--t-paper); font: 800 14px var(--sans); }
.q-lv { font: 600 12px var(--sans); color: var(--t-mute); }
.q-res { margin-left: auto; font: 700 13px var(--sans); }
.q-res.ok { color: var(--t-ok); } .q-res.bad { color: var(--t-bad); }
.q-act { display: flex; gap: 8px; margin-top: 12px; flex-wrap: wrap; }
.expl { margin-top: 12px; background: var(--t-ground); border-radius: 10px; padding: 10px 14px; font-size: calc(var(--fs) - .5px); }
.expl b { font: 800 11px var(--sans); letter-spacing: .14em; color: var(--t-accent); display: block; margin-bottom: 4px; }
.expl ol { margin: 0; padding-left: 20px; } .expl li { margin: 2px 0; }
.q.ok { border-color: var(--t-ok); box-shadow: inset 4px 0 0 var(--t-ok); } .q.bad { border-color: var(--t-bad); box-shadow: inset 4px 0 0 var(--t-bad); }

/* task renderers (shared by book pages and the test screen) */
.fs { overflow-x: auto; padding-bottom: 4px; }
.fs-row, .fs-opts { display: grid; grid-template-columns: repeat(6, var(--cell)); gap: var(--gap); justify-content: center; }
.fs { --cell: clamp(36px, calc((100vw - 132px) / 6), 78px); --gap: clamp(4px, 1.2vw, 10px); }
.tscreen .fs { --cell: clamp(40px, calc((100vw - 64px) / 6.4), 92px); }
.fs-opts { margin-top: 6px; }
.fs-opts .col { display: grid; gap: var(--gap); align-content: start; }
.fs-opts .col:nth-child(1) { grid-column: 5; } .fs-opts .col:nth-child(2) { grid-column: 6; }
.fs svg[role] { width: var(--cell); height: var(--cell); display: block; }
.fs .arr svg { width: 30px; height: 15px; display: block; }
.fs .qm { width: var(--cell); height: var(--cell); border: 2px solid var(--grid); display: grid; place-items: center; font: 800 calc(var(--cell) * .38) var(--sans); background: var(--t-paper); }
.fs .arr { display: grid; place-items: center; height: 18px; color: var(--t-ink); }
.fs .opt { border: 0; padding: 0; background: var(--t-paper); border-radius: 3px; outline: 3px solid transparent; outline-offset: 2px; }
.fs .opt[aria-pressed="true"] { outline-color: var(--t-accent); }
.fs .opt.right { outline-color: var(--t-ok); } .fs .opt.wrong[aria-pressed="true"] { outline-color: var(--t-bad); }
.me { display: grid; grid-template-columns: 1.1fr 1fr auto; gap: 18px; align-items: start; }
.me h4, .lq h4 { margin: 0 0 10px; font: 500 calc(var(--fs) + 2px) var(--sans); text-align: center; color: var(--t-ink); }
.me .eqs { font: 500 calc(var(--fs) + 4px)/2 var(--sans); white-space: nowrap; text-align: center; }
.me .sols { display: grid; gap: 10px; justify-content: center; }
.me .sols label { display: flex; align-items: center; gap: 8px; font: 500 calc(var(--fs) + 3px) var(--sans); }
.me .sols input { width: 108px; font: 500 calc(var(--fs) + 2px) var(--sans); padding: 6px 10px; border: 1.5px solid var(--t-line); border-radius: 6px; background: var(--t-paper); color: var(--t-ink); }
.me .sols input:focus { border-color: var(--t-accent); outline: none; box-shadow: 0 0 0 3px var(--t-tint2); }
.me .sols input.right { border-color: var(--t-ok); background: var(--t-ok-tint); } .me .sols input.wrong { border-color: var(--t-bad); background: var(--t-bad-tint); }
.me .sols .key { font: 700 13px var(--sans); color: var(--t-ok); }
.pad { display: grid; grid-template-columns: repeat(3, 44px); gap: 6px; border: 1px solid var(--t-line); padding: 6px; border-radius: 6px; background: var(--t-paper); }
.pad button { height: 34px; border: 1px solid var(--t-line); background: var(--t-paper); border-radius: 4px; font: 500 15px var(--sans); }
.pad button:active { background: var(--t-tint); }
.pad .del { grid-column: span 3; display: flex; justify-content: space-between; padding: 0 10px; align-items: center; }
.pad .zero { grid-column: span 3; }
@media (max-width: 640px) { .me { grid-template-columns: 1fr; } .me .pad-wrap { display: none; } .tscreen .me .pad-wrap { display: block; justify-self: center; } }
.lq { display: flex; gap: clamp(18px, 6vw, 70px); justify-content: center; align-items: flex-start; }
.lq table { border-collapse: collapse; }
.lq td { width: clamp(38px, 9.5vw, 54px); height: clamp(38px, 9.5vw, 54px); border: 1.5px solid var(--grid); text-align: center; font: 700 calc(var(--fs) + 5px) var(--sans); background: var(--t-paper); }
.lq td.qm { color: var(--t-accent); }
.lq .ans { display: grid; } .lq .ans button { width: clamp(38px, 9.5vw, 54px); height: clamp(38px, 9.5vw, 54px); border: 1.5px solid var(--grid); margin-top: -1.5px;
  background: var(--t-paper); font: 700 calc(var(--fs) + 5px) var(--sans); }
.lq .ans button[aria-pressed="true"] { background: var(--t-accent); color: #fff; }
.lq .ans button.right { background: var(--t-ok); color: #fff; } .lq .ans button.wrong[aria-pressed="true"] { background: var(--t-bad); color: #fff; }

/* check (Before you move on) */
.check-bar { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; background: var(--t-tint); border: 1px solid var(--t-tint2); border-radius: 12px; padding: 12px 14px; margin-bottom: 14px; }
.check-bar .clock { font: 800 20px var(--sans); color: var(--t-deep); font-variant-numeric: tabular-nums; }
.verdict { border-radius: 12px; padding: 14px 16px; margin: 10px 0 16px; font-weight: 600; }
.verdict.pass { background: var(--t-ok-tint); color: var(--t-ok); } .verdict.again { background: #fdf0e4; color: #a8541a; }
details.key { border: 1px solid var(--t-line); border-radius: 12px; padding: 10px 14px; background: var(--t-paper); margin-bottom: 10px; }
details.key summary { font: 700 15px var(--sans); color: var(--t-deep); cursor: pointer; }
.key-t { width: 100%; border-collapse: collapse; margin-top: 10px; font-size: 14px; }
.key-t td, .key-t th { border-top: 1px solid var(--t-line); padding: 7px 6px; vertical-align: top; text-align: left; }
.key-t th { font: 700 11px var(--sans); letter-spacing: .1em; text-transform: uppercase; color: var(--t-mute); }
.key-t td:first-child { font-weight: 800; color: var(--t-accent); white-space: nowrap; }
.key-t td:nth-child(2) { font-weight: 700; white-space: nowrap; }
.pager { display: flex; justify-content: space-between; gap: 12px; margin-top: 18px; }

/* facts table */
.facts { width: 100%; border-collapse: collapse; font-size: 14.5px; }
.facts th, .facts td { text-align: left; padding: 9px 10px; border-top: 1px solid var(--t-line); vertical-align: top; }
.facts th { width: 32%; color: var(--t-deep); }

/* ─── Test screen (practice mode modelled on the official dMAT screen) ─── */
body.tbody { padding: 0; background: var(--t-paper); }
.tscreen { min-height: 100vh; display: flex; flex-direction: column; }
.t-head { background: var(--t-deep); color: #fff; display: flex; align-items: center; gap: 18px; padding: 10px clamp(12px, 3vw, 28px); flex-wrap: wrap; position: sticky; top: 0; z-index: 20; }
html[data-theme="book"] .t-head, html:not([data-theme]) .t-head { background: #6d1650; }
.t-clock { display: inline-flex; align-items: center; gap: 6px; background: #fff; color: #1f1a24; border-radius: 999px; padding: 5px 13px; font: 700 15px var(--sans); font-variant-numeric: tabular-nums; border: 2px solid rgba(0,0,0,.15); }
.t-clock.low { color: #c0122b; }
.t-mods { display: flex; gap: 22px; }
.t-mod { font: 700 14px/1.2 var(--sans); opacity: .5; position: relative; padding-top: 7px; }
.t-mod small { display: block; font: 500 11px var(--sans); }
.t-mod.on { opacity: 1; }
.t-mod .ticks { position: absolute; top: 0; left: 0; display: flex; gap: 3px; } .t-mod .ticks i { width: 14px; height: 3px; background: rgba(255,255,255,.45); }
.t-mod .ticks i.on { background: #fff; height: 5px; margin-top: -2px; }
.t-head .sp { flex: 1; }
.t-end { background: #fff; color: #1f1a24; border: 3px solid #e8e04c; border-radius: 8px; padding: 6px 12px; font: 700 13px var(--sans); }
.t-ins { background: #f6f4f6; border-bottom: 1px solid #e6e1e5; padding: 10px clamp(12px, 3vw, 28px) 20px; font-size: 13.5px; color: #2a242c; position: relative; }
html[data-theme="night"] .t-ins { background: #241a21; color: var(--t-ink); border-color: var(--t-line); }
.t-ins b { display: block; }
.t-ins .tog { position: absolute; left: 50%; bottom: -1px; transform: translateX(-50%); border: 0; background: none; font-size: 15px; color: #6a5f6b; padding: 0 8px; }
.t-tools { display: flex; justify-content: flex-end; gap: 6px; padding: 8px clamp(12px, 3vw, 28px) 0; }
.t-tools button { border: 1.5px solid #c9b7c2; background: var(--t-paper); border-radius: 5px; font: 800 13px var(--sans); width: 30px; height: 28px; color: var(--t-accent); }
.t-tools button[aria-pressed="true"] { background: var(--t-accent); color: #fff; border-color: var(--t-accent); }
.t-tools .flag svg { width: 15px; height: 15px; }
.t-body { flex: 1; padding: 16px clamp(12px, 3vw, 28px) 24px; }
.t-body .tsize-s { --fs: 13.5px; } .t-body .tsize-l { --fs: 18px; }
.t-foot { position: sticky; bottom: 0; background: var(--t-paper); border-top: 1px solid #e6e1e5; display: flex; align-items: center; gap: 10px; padding: 9px clamp(10px, 3vw, 28px); flex-wrap: wrap; justify-content: center; z-index: 20; }
.t-brand { display: flex; align-items: center; gap: 8px; font: 700 13px var(--sans); color: var(--t-ink); margin-right: auto; }
.t-brand i { width: 22px; height: 22px; border-radius: 3px; background: linear-gradient(135deg, #4e0f37, #c43b8e); display: block; }
.t-brand small { display: block; font: 500 9.5px var(--sans); color: var(--t-mute); }
.t-nav { border: 0; background: #b5276f; color: #fff; border-radius: 6px; padding: 8px 14px; font: 700 13px var(--sans); }
.t-nav:disabled { background: #8f8a90; }
.t-nums { display: flex; flex-wrap: wrap; gap: 4px; justify-content: center; }
.t-nums button { position: relative; width: 28px; height: 28px; border: 1.5px solid #b5276f; background: #fff; color: #b5276f; border-radius: 4px; font: 700 12px var(--sans); padding: 0; }
.t-nums button.done { background: #6d1650; color: #fff; border-color: #6d1650; }
.t-nums button.cur { outline: 2px solid #1f1a24; outline-offset: 1px; }
.t-nums button.flag::after { content: ""; position: absolute; right: 1px; bottom: 1px; width: 7px; height: 7px; background: #e8e04c; border: 1px solid #6d1650; border-radius: 1px; }
.t-warn { position: fixed; inset: 0; display: grid; place-items: center; z-index: 50; pointer-events: none; }
.t-warn div { background: #fff; border-radius: 999px; padding: 18px 44px 18px 28px; display: flex; align-items: center; gap: 22px; font: 800 64px var(--sans); color: #c0122b; box-shadow: 0 20px 60px rgba(0,0,0,.35); }
.t-warn svg { width: 74px; height: 74px; }
.t-card { max-width: 720px; margin: 40px auto; background: var(--t-paper); border: 1px solid var(--t-line); border-radius: 18px; padding: clamp(20px, 4vw, 34px); }
.t-card h1 { margin: 0 0 6px; font: 800 28px/1.2 var(--sans); color: var(--t-deep); }
.t-card h2 { font: 800 18px var(--sans); color: var(--t-deep); margin: 22px 0 8px; }
.t-choices { display: grid; gap: 10px; margin: 18px 0; }
.t-choice { display: flex; justify-content: space-between; align-items: center; gap: 12px; border: 1.5px solid var(--t-line); border-radius: 12px; padding: 14px 16px; background: var(--t-paper); text-align: left; }
.t-choice:hover { border-color: var(--t-accent); background: var(--t-tint); }
.t-choice b { font: 750 16px var(--sans); color: var(--t-deep); display: block; } .t-choice small { color: var(--t-mute); font-size: 13px; }
.t-choice .go { font: 700 13px var(--sans); color: var(--t-accent); white-space: nowrap; }
.t-modal { position: fixed; inset: 0; background: rgba(31,26,36,.55); display: grid; place-items: center; z-index: 70; padding: 16px; }
.t-modal > div { background: var(--t-paper); border-radius: 16px; padding: 22px; max-width: 420px; width: 100%; }
.t-modal h3 { margin: 0 0 8px; font: 800 19px var(--sans); color: var(--t-deep); }
.t-modal .row { display: flex; gap: 8px; justify-content: flex-end; margin-top: 16px; }
.res-t { width: 100%; border-collapse: collapse; margin: 8px 0 4px; }
.res-t td, .res-t th { padding: 9px 8px; border-top: 1px solid var(--t-line); text-align: left; }
.res-t th { font: 700 11px var(--sans); text-transform: uppercase; letter-spacing: .1em; color: var(--t-mute); }
.res-t .big { font: 800 18px var(--sans); color: var(--t-deep); }
.meter { height: 8px; border-radius: 99px; background: var(--t-tint2); overflow: hidden; min-width: 90px; } .meter i { display: block; height: 100%; background: var(--t-accent); }
.trans { text-align: center; } .trans .t-clock { font-size: 18px; margin: 14px 0; }
.rv-nums { display: flex; flex-wrap: wrap; gap: 5px; margin: 10px 0 16px; }
.rv-nums button { width: 32px; height: 32px; border-radius: 6px; border: 0; color: #fff; font: 700 12.5px var(--sans); }
.rv-nums button.ok { background: var(--t-ok); } .rv-nums button.bad { background: var(--t-bad); } .rv-nums button.cur { outline: 3px solid var(--t-ink); outline-offset: 1px; }
.tracker td { font-variant-numeric: tabular-nums; }
@media print { .bar, .mast .btn, .q-act, .check-bar { display: none !important; } body { background: #fff; } .sheet { border: 0; } }
body.tbody .page { max-width: none; } body.tbody .mast, body.tbody .note { display: none; }
.grid.two { grid-template-columns: repeat(auto-fill, minmax(min(100%, 380px), 1fr)); }
.links.cols { grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); }
@media (max-width: 560px) { .bar .btn.ghost .lbl { display: none; } .bar .btn.ghost { padding: 8px 10px; } .bar .ttl { min-width: 0; font-size: 13.5px; } }
@media (max-width: 640px) { .t-brand { display: none; } .t-head { gap: 10px; } .t-mod small { display: none; } }

/* ─── General Academic Module (release 2) ─────────────────────────────────── */
.links .soon { display: flex; justify-content: space-between; align-items: center; gap: 10px; padding: 10px 12px; border: 1px dashed var(--t-line); border-radius: 10px; color: var(--t-mute); font: 600 14px var(--sans); }
.links .soon small { font: 600 11px var(--sans); letter-spacing: .06em; text-transform: uppercase; }
.ga { display: grid; gap: 18px; }
.ga-text { font: 400 calc(var(--fs) * 1.04)/1.68 var(--serif); color: var(--t-ink); }
.ga-text p { margin: 0 0 .8em; }
.ga-text h4 { font: 700 15px/1.3 var(--sans); color: var(--t-deep); margin: 1.1em 0 .4em; letter-spacing: .01em; }
.ga-head { display: flex; flex-wrap: wrap; align-items: baseline; gap: 4px 12px; border-bottom: 2px solid var(--t-tint2); padding-bottom: 10px; margin-bottom: 14px; }
.ga-head h3 { flex: 1 1 100%; order: 2; margin: 0; font: 800 calc(var(--fs) * 1.25)/1.25 var(--sans); color: var(--t-deep); }
.ga-subj { order: 1; font: 700 11.5px var(--sans); letter-spacing: .12em; text-transform: uppercase; color: var(--t-accent); }
.ga-zbar { order: 1; margin-left: auto; display: inline-flex; align-items: center; gap: 3px; font: 600 11.5px var(--sans); color: var(--t-mute); }
.ga-zbar button { border: 1px solid var(--t-line); background: var(--t-paper); color: var(--t-accent); border-radius: 6px; font: 700 11.5px var(--sans); padding: 2px 6px; }
.ga-zbar button[aria-pressed="true"] { background: var(--t-accent); border-color: var(--t-accent); color: var(--on-accent, #fff); }
.ga-f { margin: .7em 0 .9em; padding: 10px 14px; background: var(--t-tint); border-left: 3px solid var(--t-accent); border-radius: 0 10px 10px 0; font: 600 calc(var(--fs) * 1.02)/1.5 var(--sans); color: var(--t-deep); overflow-x: auto; }
.ga-fig { margin: 1em 0 1.1em; padding: 12px; background: var(--t-paper); border: 1px solid var(--t-line); border-radius: 12px; }
.ga-fig figcaption { margin-top: 8px; font: 500 12.5px/1.45 var(--sans); color: var(--t-mute); }
.ga-zoom { overflow-x: auto; }
.ga-zoom > .gfig { display: block; width: 100%; max-width: 620px; height: auto; margin: 0 auto; transition: max-width .2s; }
.ga[data-zoom="2"] .ga-zoom > .gfig { width: 160%; max-width: 1000px; } .ga[data-zoom="3"] .ga-zoom > .gfig { width: 230%; max-width: 1400px; }
.ga[data-zoom="2"] .ga-zoom > .gt { font-size: 1.25em; } .ga[data-zoom="3"] .ga-zoom > .gt { font-size: 1.5em; }
.gfig text { font-family: var(--sans); fill: var(--t-ink); font-size: 13px; }
.gfig .sm { font-size: 12px; fill: var(--t-mute); } .gfig .lbl { font-size: 13px; font-weight: 600; fill: var(--t-ink); }
.gfig .line { stroke: var(--t-line); stroke-width: 1; fill: none; } .gfig .mute { stroke: var(--t-mute); stroke-width: 1.4; fill: none; }
.gfig .ink { stroke: var(--t-ink); stroke-width: 2; fill: none; } .gfig .dash { stroke-dasharray: 5 4; }
.gfig .s1 { stroke: var(--t-accent); stroke-width: 3; fill: none; stroke-linejoin: round; stroke-linecap: round; }
.gfig .s2 { stroke: var(--t-deep); stroke-width: 3; fill: none; stroke-linejoin: round; stroke-linecap: round; }
.gfig .s3 { stroke: var(--t-gold); stroke-width: 3; fill: none; stroke-linejoin: round; stroke-linecap: round; }
.gfig .f1 { fill: var(--t-accent); } .gfig .f2 { fill: var(--t-deep); } .gfig .f3 { fill: var(--t-gold); }
.gfig text.f1, .gfig text.f2, .gfig text.f3 { font-weight: 700; }
.gt { width: 100%; border-collapse: collapse; font: 500 14px/1.4 var(--sans); }
.gt th { text-align: left; background: var(--t-tint); color: var(--t-deep); font-weight: 700; padding: 8px 10px; border-bottom: 2px solid var(--t-tint2); }
.gt td { padding: 7px 10px; border-bottom: 1px solid var(--t-line); font-variant-numeric: tabular-nums; }
.gt tbody tr:nth-child(even) td { background: color-mix(in srgb, var(--t-tint) 45%, transparent); }
.ga-qs { display: grid; gap: 12px; align-content: start; }
.ga-qi { border: 1px solid var(--t-line); border-radius: 14px; background: var(--t-paper); padding: 12px 14px 14px; }
.ga-qi.ok { border-color: var(--t-ok); box-shadow: inset 4px 0 0 var(--t-ok); } .ga-qi.bad { border-color: var(--t-bad); box-shadow: inset 4px 0 0 var(--t-bad); }
.ga-qh { display: flex; gap: 10px; align-items: flex-start; width: 100%; border: 0; background: none; padding: 0; text-align: left; color: var(--t-ink); font: 600 var(--fs)/1.5 var(--sans); cursor: default; }
.ga-qh .n { flex: 0 0 26px; height: 26px; border-radius: 8px; background: var(--t-deep); color: #fff; font: 800 13px/26px var(--sans); text-align: center; }
html[data-theme="night"] .ga-qh .n { color: #1b1419; }
.ga-qh .qt { flex: 1; } .ga-qh .st { font: 700 11px/26px var(--sans); letter-spacing: .06em; text-transform: uppercase; color: var(--t-mute); white-space: nowrap; }
.ga-qi.ok .st { color: var(--t-ok); } .ga-qi.bad .st { color: var(--t-bad); }
.ga-opts { display: grid; gap: 7px; margin: 10px 0 0 36px; }
.ga-o { display: flex; gap: 10px; align-items: flex-start; text-align: left; border: 1.5px solid var(--t-line); background: var(--t-paper); color: var(--t-ink); border-radius: 10px; padding: 8px 12px; font: 450 calc(var(--fs) * .97)/1.45 var(--sans); cursor: pointer; transition: border-color .12s, background .12s; }
.ga-o b { flex: 0 0 22px; height: 22px; border-radius: 50%; border: 1.5px solid var(--t-soft); color: var(--t-accent); font: 800 12px/19px var(--sans); text-align: center; }
.ga-o:hover { border-color: var(--t-soft); }
.ga-o[aria-pressed="true"] { border-color: var(--t-accent); background: var(--t-tint); }
.ga-o[aria-pressed="true"] b { background: var(--t-accent); border-color: var(--t-accent); color: var(--on-accent, #fff); }
.ga-o.right { border-color: var(--t-ok); background: var(--t-ok-tint); } .ga-o.right b { background: var(--t-ok); border-color: var(--t-ok); color: #fff; }
.ga-o.wrong { border-color: var(--t-bad); background: var(--t-bad-tint); } .ga-o.wrong b { background: var(--t-bad); border-color: var(--t-bad); color: #fff; }
.ga-x .expl { margin: 10px 0 0 36px; }
.ga-x .expl p { margin: 4px 0 0; font: 400 14px/1.55 var(--sans); }
.ga-qi.shut .ga-opts, .ga-qi.shut .ga-x { display: none; }
.ga-card .q-body { margin-top: 10px; }
@media (min-width: 1020px) {
  .ga-page .page { max-width: 1240px; }
  .ga { grid-template-columns: minmax(0, 1.08fr) minmax(0, 1fr); align-items: start; }
  .ga-text { position: sticky; top: 70px; max-height: calc(100vh - 90px); overflow-y: auto; padding-right: 14px; }
}
.ga.split { grid-template-columns: 1fr; }
@media (min-width: 900px) {
  .ga.split { grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr); }
  .ga.split .ga-text { position: sticky; top: 64px; max-height: calc(100vh - 190px); overflow-y: auto; padding: 4px 16px 4px 2px; border-right: 1px solid var(--t-line); }
  .ga.split .ga-qs { max-height: none; }
}
.ga.split .ga-qh { cursor: pointer; }
.ga-screen .t-body { max-width: 1400px; margin: 0 auto; width: 100%; box-sizing: border-box; }
.t-nums button.part { background: var(--t-tint2); }
/* hand-drawn diagrams: tinted area fills so labels on top stay readable */
.gfig.raw .f1 { fill: color-mix(in srgb, var(--t-accent) 32%, var(--t-paper)); }
.gfig.raw .f2 { fill: color-mix(in srgb, var(--t-deep) 22%, var(--t-paper)); }
.gfig.raw .f3 { fill: color-mix(in srgb, var(--t-gold) 45%, var(--t-paper)); }
.gfig.raw circle:not([class]), .gfig.raw rect:not([class]), .gfig.raw path:not([class]), .gfig.raw polygon:not([class]), .gfig.raw ellipse:not([class]) { fill: none; stroke: var(--t-ink); stroke-width: 1.6; }
.gfig.raw .solid.f1 { fill: var(--t-accent); } .gfig.raw .solid.f2 { fill: var(--t-deep); } .gfig.raw .solid.f3 { fill: var(--t-gold); }