/* site-v0: тетрадь и чернила. Токены из docs/research/design-concept.md, раздел 2.3. */
:root {
  color-scheme: light dark;
  --paper: #f8fbfd;
  --paper-2: #eef3f8;
  --rule: #d1d8e1;
  --line: #77818f;
  --ink: #16243c;
  --ink-2: #4c5666;
  --blue: #1f48ae;
  --blue-hover: #133796;
  --on-blue: #f8fbfd;
  --pen: #0b7643;
  --pen-bg: #ddf6e4;
  --error: #ba2b28;
  --focus: #3266e4;
  --gutter: 16px;
  --font: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    --paper: #171f2f;
    --paper-2: #212a3c;
    --rule: #374050;
    --line: #707b8c;
    --ink: #e2e9f0;
    --ink-2: #a9b2be;
    --blue: #8db0f7;
    --blue-hover: #aac4f9;
    --on-blue: #171f2f;
    --pen: #6fd395;
    --pen-bg: #1d3a2b;
    --error: #f47c70;
    --focus: #95b7fb;
  }
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

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

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font: 18px/1.55 var(--font);
  overflow-wrap: break-word;
}

.wrap {
  max-width: 42rem;
  margin-inline: auto;
  padding-inline: var(--gutter);
}

main > section {
  padding-block: 32px;
  border-top: 1px solid var(--rule);
  scroll-margin-top: 8px;
}

main > section:first-child {
  border-top: 0;
  padding-top: 24px;
}

h1,
h2 {
  margin: 0 0 12px;
  line-height: 1.2;
  font-weight: 700;
}

h1 {
  font-size: 28px;
  letter-spacing: -0.01em;
}

h2 {
  font-size: 22px;
}

h3 {
  margin: 24px 0 8px;
  font-size: 18px;
}

p,
ul {
  margin: 0 0 16px;
}

ul {
  padding-left: 1.25em;
}

li + li {
  margin-top: 6px;
}

a {
  color: var(--blue);
  text-underline-offset: 3px;
}

a:hover {
  color: var(--blue-hover);
}

:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 2px;
}

.lead {
  margin: 0;
  font-size: 20px;
  color: var(--ink-2);
}

.note {
  color: var(--ink-2);
  font-size: 15px;
}

.nb {
  white-space: nowrap;
}

/* Первый экран */
.hero {
  display: grid;
  gap: 24px;
}

.hero img {
  display: block;
  width: 100%;
  max-width: 240px;
  height: auto;
  border: 1px solid var(--rule);
  border-radius: 2px;
}

/* Блок первого занятия: поле тетради с зелёной пометкой */
.card {
  background: var(--paper-2);
  border: 1px solid var(--rule);
  border-left: 4px solid var(--pen);
  padding: 20px 16px;
}

.price {
  margin-bottom: 12px;
  font-size: 22px;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
}

/* Кнопка */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  min-height: 48px;
  padding: 12px 20px;
  border: 0;
  border-radius: 6px;
  background: var(--blue);
  color: var(--on-blue);
  font: 600 17px/1.25 var(--font);
  text-align: center;
  text-decoration: none;
  cursor: pointer;
}

.btn:hover {
  background: var(--blue-hover);
  color: var(--on-blue);
}

.btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

/* Форма */
.field {
  margin: 0 0 16px;
}

label,
legend {
  display: block;
  margin-bottom: 4px;
  padding: 0;
  font-size: 16px;
  font-weight: 600;
}

fieldset {
  min-width: 0;
  margin: 0 0 16px;
  padding: 0;
  border: 0;
}

input[type="text"],
select,
textarea {
  display: block;
  width: 100%;
  min-height: 48px;
  padding: 10px 12px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--paper);
  color: var(--ink);
  font: 16px/1.4 var(--font);
}

textarea {
  min-height: 96px;
  resize: vertical;
}

.row {
  display: grid;
  gap: 0 16px;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 13rem), 1fr));
}

.choice {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 24px;
}

.choice label,
.agree {
  display: flex;
  align-items: center;
  gap: 10px;
  min-height: 44px;
  margin: 0;
  font-weight: 400;
}

.agree {
  align-items: flex-start;
  margin-bottom: 16px;
  padding-block: 8px;
  font-size: 16px;
  line-height: 1.4;
}

input[type="radio"],
input[type="checkbox"] {
  flex: none;
  width: 24px;
  height: 24px;
  margin: 0;
  accent-color: var(--blue);
}

.status {
  margin: 16px 0 0;
  padding: 12px 14px;
  border: 1px solid var(--rule);
  border-radius: 6px;
  font-size: 16px;
  font-weight: 600;
}

.status:empty {
  margin: 0;
  padding: 0;
  border: 0;
}

.status[data-kind="ok"] {
  background: var(--pen-bg);
  border-color: var(--pen);
  color: var(--pen);
}

.status[data-kind="error"] {
  border-color: var(--error);
  color: var(--error);
}

[hidden] {
  display: none !important;
}

/* Подвал */
.foot {
  margin-top: 8px;
  padding-block: 24px 40px;
  border-top: 1px solid var(--rule);
  font-size: 16px;
}

.foot ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

.foot li + li {
  margin-top: 0;
}

.foot a {
  display: inline-block;
  padding-block: 10px;
}

/* Юридические страницы и 404 */
.doc {
  padding-block: 24px 16px;
}

.doc h2 {
  margin-top: 28px;
  font-size: 20px;
}

.back {
  margin: 0 0 16px;
  padding-top: 16px;
  font-size: 16px;
}

.back a {
  display: inline-block;
  padding-block: 10px;
}

@media (min-width: 600px) {
  h1 {
    font-size: 40px;
  }

  h2 {
    font-size: 26px;
  }

  .hero {
    grid-template-columns: 1fr 240px;
    align-items: center;
    gap: 32px;
  }

  .btn {
    width: auto;
    padding-inline: 28px;
  }

  .doc h1 {
    font-size: 32px;
  }
}