/* Тренажёр по математике — «тетрадь в клетку». */

:root {
  color-scheme: light;
  --paper: #fbfaf4;
  --desk: #eef1f4;
  --grid: #cfdcea;
  --graphite: #2a2d33;
  --pen: #2447a8;
  --pen-soft: #e6ecfb;
  --marker: #fff0a0;
  --red: #c8322d;
  --red-soft: #fde9e7;
  --green: #1f7a4a;
  --green-soft: #e3f4ea;
  --amber-soft: #fff6d6;
  --muted: #6b7280;
  --line: #d9dee5;
  --card: #ffffff;
  --radius: 14px;
  --font: "Segoe UI", system-ui, -apple-system, Roboto, "Helvetica Neue", Arial, sans-serif;
  --digits: "Segoe UI", system-ui, -apple-system, Roboto, Arial, sans-serif;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--desk);
  color: var(--graphite);
  font: 17px/1.45 var(--font);
}
button { font: inherit; color: inherit; }
a { color: var(--pen); }
[hidden] { display: none !important; }

#app { max-width: 1040px; margin: 0 auto; padding: 12px 16px 40px; }

/* ---------- шапка ---------- */

.topbar {
  display: flex;
  align-items: center;
  gap: 12px;
  min-height: 56px;
  margin-bottom: 8px;
  flex-wrap: wrap;
}
.topbar h1 { font-size: 1.25rem; margin: 0; flex: 1 1 auto; font-weight: 650; }
.back {
  border: 0;
  background: none;
  padding: 10px 8px 10px 0;
  color: var(--pen);
  font-weight: 600;
  cursor: pointer;
  text-decoration: none;
  min-height: 44px;
}
.brand-mark {
  width: 40px; height: 40px;
  display: grid; place-items: center;
  border-radius: 10px;
  background: var(--pen);
  color: #fff;
  font-size: 1.6rem;
  font-weight: 700;
}

.progress { display: flex; gap: 6px; align-items: center; }
.pdot { width: 14px; height: 14px; border-radius: 50%; background: var(--line); }
.pdot-now { background: var(--pen); box-shadow: 0 0 0 3px var(--pen-soft); }
.pdot-clean { background: var(--green); }
.pdot-err { background: #e0a100; }

/* ---------- главная и карточки ---------- */

.today {
  display: flex;
  align-items: center;
  gap: 14px;
  background: var(--card);
  border-radius: var(--radius);
  padding: 16px 18px;
  margin: 4px 0 16px;
  border: 1px solid var(--line);
}
.today-num { font-size: 2.4rem; font-weight: 750; color: var(--pen); line-height: 1; min-width: 1.4ch; text-align: center; }
.streak { color: var(--green); font-weight: 600; }

.lead { margin: 0 0 14px; color: var(--muted); }

.cards { display: grid; gap: 12px; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); }
.card {
  display: flex;
  align-items: center;
  gap: 14px;
  text-align: left;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px;
  text-decoration: none;
  color: inherit;
  cursor: pointer;
  min-height: 76px;
  transition: border-color .15s, box-shadow .15s, transform .15s;
}
.card:hover { border-color: var(--pen); box-shadow: 0 4px 14px rgba(36, 71, 168, .12); }
.card:active { transform: translateY(1px); }
.card:focus-visible, .btn:focus-visible, .key:focus-visible, .back:focus-visible, .tap:focus-visible {
  outline: 3px solid var(--pen); outline-offset: 2px;
}
.card-glyph {
  flex: none;
  width: 52px; height: 52px;
  display: grid; place-items: center;
  border-radius: 12px;
  background: var(--pen-soft);
  color: var(--pen);
  font-size: 2rem;
  font-weight: 700;
}
.card-body { display: flex; flex-direction: column; gap: 2px; min-width: 0; }
.card-title { font-weight: 650; }
.card-sub { color: var(--muted); font-size: .92rem; }
.level-example {
  flex: none;
  min-width: 108px;
  padding: 8px 10px;
  border-radius: 10px;
  background: var(--paper);
  border: 1px dashed var(--grid);
  color: var(--pen);
  font: 600 1.05rem var(--digits);
  font-variant-numeric: tabular-nums;
  text-align: center;
}

.foot { margin-top: 28px; text-align: center; }
.foot a { color: var(--muted); }
.warn { background: var(--amber-soft); padding: 10px 14px; border-radius: 10px; }
.muted { color: var(--muted); }

/* ---------- занятие ---------- */

.work { display: grid; gap: 16px; align-items: start; }
@media (min-width: 860px) {
  .work { grid-template-columns: minmax(0, 1fr) 360px; }
}

.sheet-wrap {
  background: var(--paper);
  border-radius: var(--radius);
  border: 1px solid var(--line);
  display: flex;
  justify-content: center;
  overflow-x: auto;
  padding: 8px 0;
}

.sheet {
  --cell: min(54px, calc((min(100vw, 600px) - 56px) / (var(--cols) + 2)));
  display: grid;
  grid-template-columns: repeat(var(--cols), var(--cell));
  grid-auto-rows: var(--cell);
  padding: var(--cell);
  background-color: var(--paper);
  background-image:
    linear-gradient(to right, var(--grid) 1px, transparent 1px),
    linear-gradient(to bottom, var(--grid) 1px, transparent 1px);
  background-size: var(--cell) var(--cell);
  background-position: -1px -1px;
}

.cell {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  font: 500 calc(var(--cell) * .64) / 1 var(--digits);
  font-variant-numeric: tabular-nums;
  padding: 0;
  border: 0;
  background: none;
  user-select: none;
}
.cell.given { color: var(--graphite); font-weight: 600; }
.cell.ink { color: var(--pen); }
.cell.dot { color: var(--pen); opacity: .55; font-weight: 800; }
.cell.minus { color: var(--pen); font-weight: 700; font-size: calc(var(--cell) * .8); transform: translate(20%, -50%); }

/* черта под произведением и под делителем */
.cell.uline::after, .cell.dline::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: -1px;
  height: 2px;
  background: var(--graphite);
}
.cell.uline::after { background: var(--pen); }
/* вертикальная черта «уголка» */
.cell.bar::before {
  content: "";
  position: absolute;
  top: 0; bottom: 0; left: -1px;
  width: 2px;
  background: var(--graphite);
}

/* дужка над первым неполным делимым */
.cell.mark::after {
  content: "";
  position: absolute;
  left: 0; right: 0; top: 4%;
  height: 16%;
  border-top: 2.5px solid var(--pen);
}
.cell.mark-start::after { left: 12%; border-left: 2.5px solid var(--pen); border-top-left-radius: 10px; }
.cell.mark-end::after { right: 12%; border-right: 2.5px solid var(--pen); border-top-right-radius: 10px; }

.cell.active {
  background: var(--marker);
  box-shadow: inset 0 0 0 2px #e8cf52;
  border-radius: 4px;
}
.cell.typed { color: var(--pen); font-weight: 600; }
.cell.wrong { color: var(--red); text-decoration: line-through; text-decoration-thickness: 2px; }
.cell.rem { color: var(--green); font-weight: 700; }

.sheet-tap .cell.tap {
  cursor: pointer;
  border-radius: 8px;
  background: var(--pen-soft);
  box-shadow: inset 0 0 0 1.5px #b8c7ee;
  margin: 2px;
}
.sheet-tap .cell.tap:hover { background: var(--marker); }

@keyframes shake {
  0%, 100% { translate: 0; }
  20% { translate: -5px; }
  40% { translate: 5px; }
  60% { translate: -3px; }
  80% { translate: 3px; }
}
.shake { animation: shake .35s ease; }
@media (prefers-reduced-motion: reduce) { .shake { animation: none; } .card { transition: none; } }

/* ---------- панель ответа ---------- */

.panel {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.prompt { margin: 0; font-size: 1.12rem; font-weight: 600; min-height: 3em; }
.result { display: flex; flex-direction: column; gap: 4px; }
.result strong { font-size: 1.5rem; color: var(--pen); font-variant-numeric: tabular-nums; }
.check-line { color: var(--muted); font-weight: 500; font-variant-numeric: tabular-nums; }

.answer-box {
  align-self: flex-start;
  min-width: 96px;
  padding: 6px 16px;
  border-radius: 10px;
  background: var(--marker);
  box-shadow: inset 0 0 0 2px #e8cf52;
  font: 600 2rem/1.2 var(--digits);
  color: var(--pen);
  text-align: center;
  font-variant-numeric: tabular-nums;
}
.answer-box.empty { color: #b7a44a; }
.answer-box.wrong { color: var(--red); text-decoration: line-through; }

.feedback { margin: 0; padding: 10px 12px; border-radius: 10px; min-height: 2.9em; }
.fb-good { background: var(--green-soft); color: var(--green); font-weight: 600; }
.fb-bad { background: var(--red-soft); color: #8f1f1a; }
.fb-hint { background: var(--amber-soft); color: #6a5300; }
.fb-info { background: #f3f5f8; color: var(--muted); }

.numpad { display: grid; grid-template-columns: repeat(3, 1fr); gap: 8px; }
.key {
  min-height: 58px;
  border-radius: 12px;
  border: 1px solid var(--line);
  background: #f7f8fa;
  font-size: 1.5rem;
  font-weight: 600;
  cursor: pointer;
  touch-action: manipulation;
}
.key:hover { background: var(--pen-soft); }
.key:active { transform: translateY(1px); background: #dfe6f8; }
.key-ok { background: var(--pen); color: #fff; border-color: var(--pen); }
.key-ok:hover { background: #1c3a8c; }
.key-back { color: var(--muted); }

.panel-actions { display: flex; gap: 8px; flex-wrap: wrap; }
.btn {
  min-height: 48px;
  padding: 10px 18px;
  border-radius: 12px;
  border: 1px solid var(--line);
  background: #fff;
  font-weight: 600;
  cursor: pointer;
  touch-action: manipulation;
}
.btn-primary { background: var(--pen); color: #fff; border-color: var(--pen); }
.btn-primary:hover { background: #1c3a8c; }
.btn-quiet { background: #f3f5f8; }
.btn-next { flex: 1 1 auto; font-size: 1.1rem; }

/* ---------- итог ---------- */

.summary {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px 20px;
  text-align: center;
  max-width: 560px;
  margin: 12px auto;
}
.summary h2 { margin: 0 0 6px; font-size: 1.6rem; }
.summary-big { font-size: 3.2rem; font-weight: 750; color: var(--pen); margin: 8px 0 0; line-height: 1.1; }
.summary-mistakes { text-align: left; margin: 18px auto 0; max-width: 360px; }
.summary-mistakes h3 { font-size: 1rem; margin: 0 0 6px; }
.summary-mistakes ul { list-style: none; padding: 0; margin: 0; }
.summary-mistakes li { display: flex; justify-content: space-between; padding: 6px 0; border-bottom: 1px solid var(--line); }
.summary-mistakes .count { color: var(--muted); font-variant-numeric: tabular-nums; }
.summary-actions { display: flex; gap: 10px; justify-content: center; flex-wrap: wrap; margin-top: 22px; }

/* ---------- для родителей ---------- */

.parent-block {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
  margin-bottom: 16px;
}
.parent-block h2 { margin: 0 0 8px; font-size: 1.3rem; }
.parent-block h3 { margin: 20px 0 8px; font-size: 1rem; }
.stats-week { margin: 0 0 8px; }
.advice { background: var(--amber-soft); border-radius: 10px; padding: 10px 12px; margin: 8px 0; }
.table-wrap { overflow-x: auto; }
table { border-collapse: collapse; width: 100%; font-size: .95rem; }
th, td { text-align: left; padding: 7px 10px 7px 0; border-bottom: 1px solid var(--line); vertical-align: top; }
th { color: var(--muted); font-weight: 600; font-size: .85rem; }
td.num { font-variant-numeric: tabular-nums; white-space: nowrap; }
td.ok { color: var(--green); }
.bars { list-style: none; padding: 0; margin: 0; display: grid; gap: 8px; }
.bars li { display: grid; grid-template-columns: minmax(120px, 220px) 1fr 40px; gap: 10px; align-items: center; }
.bar-track { height: 12px; background: #f0f2f5; border-radius: 6px; overflow: hidden; }
.bar-fill { display: block; height: 100%; background: var(--pen); border-radius: 6px; }
.bar-num { text-align: right; font-variant-numeric: tabular-nums; color: var(--muted); }
.settings { margin: 18px 0 14px; display: grid; gap: 10px; max-width: 420px; }
.setting { display: flex; justify-content: space-between; align-items: center; gap: 12px; min-height: 44px; }
.setting input[type=number] { width: 84px; font: inherit; padding: 8px; border: 1px solid var(--line); border-radius: 8px; }
.setting input[type=checkbox] { width: 24px; height: 24px; }

/* ---------- текст о тренажёре и подвал (index.html) ---------- */

.about, .site-foot { max-width: 1040px; margin: 0 auto; padding: 0 16px; color: #4b5563; }
.about { padding-bottom: 8px; }
.about h2 { font-size: 1.1rem; color: var(--graphite); margin: 8px 0 8px; }
.about p, .about ol { margin: 0 0 10px; max-width: 70ch; }
.about ol { padding-left: 1.3em; }
.site-foot { padding-bottom: 32px; font-size: .92rem; }
.site-foot a { color: var(--muted); }
body:not([data-screen="home"]) .about { display: none; }
body[data-screen="trainer"] .site-foot { display: none; }

@media (max-width: 520px) {
  body { font-size: 16px; }
  #app { padding: 8px 12px 32px; }
  .bars li { grid-template-columns: 1fr 60px 32px; }
  .key { min-height: 54px; }
}