:root {
  --paper: #fbfcfe;
  --grid: #e0e8f4;
  --margin: #f0a3ad;
  --ink: #1d3f8f;
  --ink-soft: #e9eefa;
  --red: #cf2f3d;
  --red-soft: #fdecee;
  --green: #1c8249;
  --green-soft: #e5f3eb;
  --text: #1a2130;
  --muted: #5a6477;
  --line: #cfd9e8;
  --amber: #c98a00;
  --cell: 24px;
  --gutter: 56px;
  --sans: 'Golos Text', system-ui, sans-serif;
  --serif: 'PT Serif', Georgia, serif;
  --hand: 'Caveat', 'Segoe Print', cursive;
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  min-height: 100vh;
  color: var(--text);
  font: 400 17px/1.5 var(--sans);
  background-color: var(--paper);
  background-image:
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: var(--cell) var(--cell);
}

button { font: inherit; color: inherit; cursor: pointer; }
button:disabled { cursor: default; }
:focus-visible { outline: 3px solid var(--ink); outline-offset: 2px; }

/* Лист: розовая линия полей слева, как в школьной тетради */
.sheet {
  position: relative;
  max-width: 760px;
  min-height: 100vh;
  margin: 0 auto;
  padding: 32px 20px 64px var(--gutter);
}
.sheet::before {
  content: '';
  position: absolute;
  top: 0; bottom: 0;
  left: calc(var(--gutter) - 14px);
  width: 2px;
  background: var(--margin);
}

h1, h2 { font-weight: 700; letter-spacing: -0.01em; margin: 0; }
h1 { font-size: 40px; line-height: 1.1; }
h2 { font-size: 26px; line-height: 1.2; }
p { margin: 0; }
.muted { color: var(--muted); }
.lead { max-width: 60ch; color: var(--muted); margin-top: 16px; }

/* Математика */
.m, .task-x, .opt-val, .formula { font-family: var(--serif); }
i { font-style: italic; }
sup { font-size: 0.7em; line-height: 0; }

/* ───── Главный экран ───── */
.home-head { padding-top: 24px; }
.formula {
  font: 500 34px/1.2 var(--hand);
  color: var(--ink);
  margin-top: 20px;
  transform: rotate(-1.5deg);
  transform-origin: left center;
}
.formula i { font-style: normal; }
.home .lead { margin-top: 20px; }

.resume {
  margin-top: 32px;
  padding: 16px 18px;
  border-left: 4px solid var(--ink);
  background: var(--ink-soft);
  display: flex; flex-wrap: wrap; gap: 12px 20px; align-items: center; justify-content: space-between;
}

.roles {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-top: 32px;
}
.role {
  text-align: left;
  padding: 22px 22px 20px;
  background: #fff;
  border: 2px solid var(--ink);
  border-radius: 6px;
  display: flex; flex-direction: column; gap: 6px;
  box-shadow: 4px 4px 0 var(--ink-soft);
  transition: transform .12s, box-shadow .12s;
}
.role:hover { transform: translate(-2px, -2px); box-shadow: 6px 6px 0 var(--ink-soft); }
.role:active { transform: none; box-shadow: 2px 2px 0 var(--ink-soft); }
.role-name { font-size: 24px; font-weight: 700; color: var(--ink); }
.role-hint { color: var(--muted); font-size: 15px; }

.note-local {
  margin-top: 32px;
  font-size: 14px;
  color: var(--muted);
  border-top: 1px dashed var(--line);
  padding-top: 12px;
}

/* ───── Кнопки ───── */
.btn {
  border: 2px solid var(--ink);
  background: var(--ink);
  color: #fff;
  font-weight: 600;
  padding: 10px 20px;
  border-radius: 6px;
  min-height: 46px;
}
.btn:hover:not(:disabled) { background: #16326f; border-color: #16326f; }
.btn.ghost { background: #fff; color: var(--ink); }
.btn.ghost:hover:not(:disabled) { background: var(--ink-soft); color: var(--ink); }
.btn:disabled { opacity: .35; }
.btn.small { padding: 6px 14px; min-height: 38px; font-size: 15px; }
.btn.danger { background: #fff; color: var(--red); border-color: var(--red); }
.btn.danger:hover { background: var(--red-soft); }

/* ───── Модальное окно ───── */
.modal {
  position: fixed; inset: 0;
  background: rgba(20, 30, 60, .45);
  display: grid; place-items: center;
  padding: 16px;
  z-index: 10;
}
.modal[hidden] { display: none; }
.modal-card {
  width: min(440px, 100%);
  background: var(--paper);
  border-radius: 8px;
  padding: 24px;
  box-shadow: 0 20px 50px rgba(20, 30, 60, .3);
}
.modal-card h2 { font-size: 22px; }
.modal-card .muted { margin-top: 6px; font-size: 15px; }
.modal-card input {
  width: 100%;
  margin-top: 16px;
  font: 500 18px var(--sans);
  padding: 12px 14px;
  border: 2px solid var(--line);
  border-radius: 6px;
  background: #fff;
}
.modal-card input:focus { outline: none; border-color: var(--ink); }
.form-error { color: var(--red); font-size: 15px; margin-top: 8px; }
.modal-actions { display: flex; justify-content: flex-end; gap: 10px; margin-top: 20px; }

/* ───── Шапка теста ───── */
.bar {
  display: flex; justify-content: space-between; align-items: flex-start; gap: 16px;
  padding-bottom: 16px;
  border-bottom: 2px solid var(--ink);
}
.bar-name { font-size: 20px; font-weight: 700; }
.bar-meta { color: var(--muted); font-size: 15px; }
.sync, .conn { font-size: 14px; color: var(--muted); white-space: nowrap; }
.sync::before, .conn::before {
  content: ''; display: inline-block; width: 8px; height: 8px; border-radius: 50%;
  margin-right: 6px; vertical-align: 1px; background: var(--green);
}
.sync[data-state="saving"]::before { background: var(--amber); }
.sync[data-state="error"]::before, .conn[data-on="false"]::before { background: var(--red); }
.sync[data-state="error"] { color: var(--red); }

/* ───── Навигация по заданиям ───── */
.qnav {
  display: flex; flex-wrap: wrap; gap: 12px 24px;
  margin: 20px 0 8px;
}
.qnav-group { display: flex; flex-direction: column; gap: 4px; }
.qnav-label { font-size: 13px; color: var(--muted); }
.qnav-cells { display: flex; gap: 6px; }
.cell {
  width: 40px; height: 40px;
  display: grid; place-items: center;
  border: 1.5px solid var(--line);
  border-radius: 4px;
  background: #fff;
  font-weight: 600; font-size: 16px;
  color: var(--muted);
}
button.cell:hover { border-color: var(--ink); color: var(--ink); }
.cell.ok { background: var(--green-soft); border-color: var(--green); color: var(--green); }
.cell.bad { background: var(--red-soft); border-color: var(--red); color: var(--red); }
.cell.current { box-shadow: 0 0 0 2px var(--paper), 0 0 0 4px var(--ink); color: var(--ink); }

/* ───── Задание ───── */
.task {
  position: relative;
  margin-top: 24px;
  padding: 20px 0 8px;
}
.task-margin {
  position: absolute;
  left: calc(-1 * var(--gutter));
  width: calc(var(--gutter) - 14px);
  top: 18px;
  text-align: center;
}
.task-num { font: 700 34px/1 var(--hand); color: var(--ink); }
.task-sec { font-size: 14px; color: var(--muted); }
.task-q { font-size: 18px; margin-top: 2px; }
.task-x {
  font-size: 34px;
  line-height: 1.3;
  margin: 14px 0 22px;
  color: var(--text);
  overflow-wrap: anywhere;
}

.opts {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}
.opt {
  display: flex; align-items: center; gap: 14px;
  text-align: left;
  min-height: 64px;
  padding: 10px 16px 10px 12px;
  background: #fff;
  border: 2px solid var(--line);
  border-radius: 6px;
}
button.opt:hover { border-color: var(--ink); background: var(--ink-soft); }
.opt-letter {
  flex: none;
  width: 30px; height: 30px;
  display: grid; place-items: center;
  border-radius: 50%;
  border: 1.5px solid currentColor;
  color: var(--muted);
  font-weight: 600; font-size: 15px;
}
.opt-val { font-size: 22px; line-height: 1.25; overflow-wrap: anywhere; }
.opt.right { border-color: var(--green); background: var(--green-soft); }
.opt.right .opt-letter { color: var(--green); background: #fff; }
.opt.wrong { border-color: var(--red); background: var(--red-soft); }
.opt.wrong .opt-letter { color: var(--red); background: #fff; }
.opt:not(.right):not(.wrong) { opacity: 1; }
.task .opts:has(.chosen) .opt:not(.right):not(.wrong) { opacity: .55; }
.opt.chosen { position: relative; }
.opt.chosen::after {
  content: 'выбран';
  position: absolute; top: -10px; right: 10px;
  font: 700 18px/1 var(--hand);
  padding: 0 6px;
  background: var(--paper);
  color: inherit;
}
.opt.right.chosen::after { color: var(--green); }
.opt.wrong.chosen::after { color: var(--red); }

.fb { min-height: 8px; }
.verdict { margin-top: 18px; font-weight: 700; font-size: 18px; }
.verdict.ok { color: var(--green); }
.verdict.bad { color: var(--red); }
.verdict.none { color: var(--muted); font-weight: 500; }

/* Подсказка — пометка учителя красной ручкой */
.hint {
  margin-top: 12px;
  padding: 14px 18px 16px;
  border: 2px solid var(--red);
  border-radius: 10px 4px 10px 4px;
  color: #7b1820;
  background: #fff;
  font-size: 17px;
  line-height: 1.6;
  max-width: 64ch;
  animation: note-in .25s ease-out;
}
.hint-title {
  display: block;
  font: 700 26px/1 var(--hand);
  color: var(--red);
  margin-bottom: 6px;
}
.hint .m { color: var(--text); }
@keyframes note-in { from { opacity: 0; transform: translateY(-4px); } }

.pager {
  display: flex; gap: 10px; flex-wrap: wrap;
  margin-top: 32px;
  padding-top: 20px;
  border-top: 1px dashed var(--line);
}
.pager .finish, .pager .danger { margin-left: auto; }

/* ───── Результат ученика ───── */
.result-head { padding-bottom: 8px; }
.score { font-size: 22px; margin-top: 8px; color: var(--muted); }
.score-num {
  font: 700 88px/1 var(--hand);
  color: var(--red);
  vertical-align: -12px;
  margin-right: 4px;
}
.result-head .sync { margin-top: 10px; }

/* ───── Учитель ───── */
.tools { display: flex; flex-wrap: wrap; gap: 12px; align-items: center; margin: 20px 0 8px; }
.tools[hidden] { display: none; }
.tools input {
  flex: 1 1 220px;
  font: 16px var(--sans);
  padding: 10px 14px;
  border: 2px solid var(--line);
  border-radius: 6px;
  background: #fff;
}
.tools input:focus { outline: none; border-color: var(--ink); }
.chips { display: flex; flex-wrap: wrap; gap: 6px; }
.chip {
  border: 1.5px solid var(--line);
  background: #fff;
  padding: 6px 12px;
  border-radius: 999px;
  font-size: 14px;
}
.chip.on { background: var(--ink); border-color: var(--ink); color: #fff; }

.works { list-style: none; margin: 12px 0 0; padding: 0; display: flex; flex-direction: column; gap: 8px; }
.work {
  width: 100%;
  display: grid;
  grid-template-columns: auto 1fr auto auto;
  align-items: center;
  gap: 14px;
  padding: 12px 16px;
  background: #fff;
  border: 1.5px solid var(--line);
  border-radius: 6px;
  text-align: left;
}
.work:hover { border-color: var(--ink); }
.work-main { display: flex; flex-direction: column; min-width: 0; }
.work-name { font-weight: 600; font-size: 17px; overflow-wrap: anywhere; }
.work-when { font-size: 14px; color: var(--muted); }
.work-score { font-size: 15px; color: var(--muted); white-space: nowrap; }
.work-score b { font-size: 22px; color: var(--text); }

.dot { width: 10px; height: 10px; border-radius: 50%; display: inline-block; background: var(--line); flex: none; }
.dot.done { background: var(--green); }
.dot.idle { background: #b7c0cf; }
.dot.live { background: var(--amber); box-shadow: 0 0 0 0 rgba(201, 138, 0, .5); animation: pulse 1.6s infinite; }
@keyframes pulse { 70% { box-shadow: 0 0 0 8px rgba(201, 138, 0, 0); } 100% { box-shadow: 0 0 0 0 rgba(201, 138, 0, 0); } }

.mini { display: flex; gap: 3px; }
.mini i { width: 9px; height: 18px; border-radius: 2px; background: var(--grid); }
.mini i.ok { background: var(--green); }
.mini i.bad { background: var(--red); }

.empty { color: var(--muted); padding: 32px 0; max-width: 50ch; }

.detail-head { margin-top: 20px; }
.detail-head h2 { margin-top: 16px; }
.detail-status { display: flex; align-items: center; gap: 8px; color: var(--muted); margin-top: 4px; }
.facts { display: flex; flex-wrap: wrap; gap: 8px 32px; margin: 16px 0 0; }
.facts dt { font-size: 13px; color: var(--muted); }
.facts dd { margin: 0; font-weight: 500; }
.task.is-current::after {
  content: 'ученик сейчас здесь';
  position: absolute; top: 12px; right: 0;
  font: 700 22px/1 var(--hand);
  color: var(--amber);
}
.teacher .task { border-top: 1px dashed var(--line); }

/* ───── Проверка связи ───── */
.linkish {
  background: none; border: 0; padding: 0;
  color: var(--ink); text-decoration: underline; text-underline-offset: 3px;
  font: inherit;
}
.home-foot { margin-top: 24px; font-size: 15px; }
.sent { margin-top: 12px; font-weight: 600; }
.sent[data-state="ok"] { color: var(--green); }
.sent[data-state="saving"] { color: var(--amber); }
.sent[data-state="error"] { color: var(--red); font-weight: 500; }
.checks { list-style: none; margin: 20px 0 0; padding: 0; display: flex; flex-direction: column; gap: 10px; }
.chk {
  display: grid; grid-template-columns: 28px 1fr; column-gap: 10px;
  padding: 12px 14px; background: #fff; border: 1.5px solid var(--line); border-radius: 6px;
}
.chk::before {
  grid-row: 1 / 3; width: 24px; height: 24px; border-radius: 50%;
  display: grid; place-items: center; font-weight: 700; font-size: 14px; color: #fff;
  content: '…'; background: var(--amber);
}
.chk.ok::before { content: '✓'; background: var(--green); }
.chk.bad::before { content: '✗'; background: var(--red); }
.chk.bad { border-color: var(--red); }
.check-title { font-weight: 600; }
.check-detail { font-size: 14px; color: var(--muted); overflow-wrap: anywhere; }
.pending { margin-top: 20px; padding: 14px 18px; border-left: 4px solid var(--red); background: var(--red-soft); }
.pending ul { margin: 8px 0 12px; padding-left: 20px; }
.pending-none { margin-top: 20px; }

/* ───── Телефон ───── */
@media (max-width: 600px) {
  :root { --gutter: 40px; }
  body { font-size: 16px; }
  .sheet { padding: 20px 16px 48px var(--gutter); }
  h1 { font-size: 32px; }
  .formula { font-size: 28px; }
  .roles { grid-template-columns: 1fr; }
  .bar { flex-direction: column; gap: 6px; }
  .cell { width: 34px; height: 34px; font-size: 15px; }
  .qnav-cells { gap: 5px; }
  .task-num { font-size: 28px; }
  .task-x { font-size: 28px; }
  .opts { grid-template-columns: 1fr; gap: 10px; }
  .opt { min-height: 56px; }
  .opt-val { font-size: 20px; }
  .score-num { font-size: 72px; }
  .work { grid-template-columns: auto 1fr auto; }
  .mini { grid-column: 2 / 4; grid-row: 2; }
  .work-score { grid-column: 3; grid-row: 1; }
  .task.is-current::after { position: static; display: block; margin-bottom: 6px; }
  .pager .finish { margin-left: 0; flex-basis: 100%; }
}

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