:root {
  color-scheme: light;
  --bg: #f6f6f2;
  --ink: #202124;
  --muted: #62676c;
  --line: #d8d8d0;
  --panel: #ffffff;
  --panel-subtle: #fafaf7;
  --accent: #245c73;
  --accent-strong: #17475a;
  --ok: #2f6f4e;
  --warn: #9a5a1f;
  --danger: #9d2d2d;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Yu Gothic", sans-serif;
  line-height: 1.7;
}

a {
  color: var(--accent-strong);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

button,
input {
  font: inherit;
}

.shell {
  min-height: 100vh;
  display: grid;
  grid-template-rows: auto 1fr;
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 14px 24px;
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.94);
}

.brand {
  color: var(--ink);
  font-weight: 700;
  letter-spacing: 0;
  text-decoration: none;
}

.topnav {
  display: flex;
  align-items: center;
  gap: 14px;
  font-size: 14px;
}

.topnav a {
  color: var(--muted);
  text-decoration: none;
}

main {
  width: min(1120px, 100%);
  padding: 36px 24px 64px;
}

h1 {
  margin: 0 0 16px;
  font-size: 28px;
  line-height: 1.35;
  letter-spacing: 0;
}

h2 {
  margin: 28px 0 12px;
  font-size: 20px;
  line-height: 1.45;
  letter-spacing: 0;
}

h3 {
  margin: 22px 0 8px;
  font-size: 17px;
  letter-spacing: 0;
}

p {
  max-width: 780px;
}

.page-head {
  display: grid;
  gap: 8px;
  margin-bottom: 24px;
}

.eyebrow {
  color: var(--accent);
  font-size: 13px;
  font-weight: 700;
}

.muted {
  color: var(--muted);
}

.panel {
  margin-top: 24px;
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
}

.section-band {
  margin-top: 28px;
  padding-top: 24px;
  border-top: 1px solid var(--line);
}

.grid-list {
  display: grid;
  gap: 12px;
  margin: 20px 0 0;
}

.item-row {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 16px;
  align-items: center;
  padding: 14px 0;
  border-bottom: 1px solid var(--line);
}

.item-row:first-child {
  border-top: 1px solid var(--line);
}

.item-title {
  margin: 0;
  font-weight: 700;
}

.item-meta {
  margin: 2px 0 0;
  color: var(--muted);
  font-size: 13px;
}

.badge {
  display: inline-flex;
  align-items: center;
  min-height: 28px;
  padding: 2px 10px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--muted);
  background: var(--panel-subtle);
  font-size: 13px;
}

.badge.available {
  border-color: #b8d4c4;
  color: var(--ok);
  background: #f2faf5;
}

.button-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 18px;
}

.button,
.primary-action {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 40px;
  padding: 8px 14px;
  border: 1px solid var(--accent);
  border-radius: 8px;
  background: var(--accent);
  color: #fff;
  font-weight: 700;
  text-decoration: none;
  cursor: pointer;
}

.button.secondary {
  border-color: var(--line);
  background: var(--panel);
  color: var(--ink);
}

.button:disabled,
.primary-action:disabled {
  cursor: not-allowed;
  opacity: 0.56;
}

.message {
  color: var(--muted);
  font-size: 14px;
}

.definition-list {
  display: grid;
  gap: 12px;
  margin: 10px 0 0;
}

.definition-list div {
  display: grid;
  grid-template-columns: 160px minmax(0, 1fr);
  gap: 16px;
  padding: 10px 0;
  border-top: 1px solid var(--line);
}

.definition-list dt {
  color: var(--muted);
  font-size: 13px;
}

.definition-list dd {
  margin: 0;
  overflow-wrap: anywhere;
}

.login-options {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.consent-stack {
  display: grid;
  gap: 16px;
  max-width: 920px;
}

.consent-item {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  overflow: clip;
}

.consent-item summary {
  cursor: pointer;
  padding: 16px 18px;
  font-weight: 700;
}

.consent-meta {
  display: block;
  color: var(--muted);
  font-size: 13px;
  font-weight: 400;
}

.consent-body {
  max-height: 360px;
  overflow: auto;
  padding: 0 18px 18px;
  border-top: 1px solid var(--line);
  white-space: pre-wrap;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 13px;
  line-height: 1.65;
}

.consent-actions {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
  margin-top: 20px;
}

.consent-checks {
  display: grid;
  gap: 10px;
  margin: 20px 0 0;
}

.consent-checks label {
  display: flex;
  gap: 10px;
  align-items: flex-start;
}

.curriculum-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 280px;
  gap: 36px;
  align-items: start;
}

.side-panel {
  position: sticky;
  top: 84px;
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
}

.side-panel ul {
  display: grid;
  gap: 8px;
  margin: 10px 0 0;
  padding: 0;
  list-style: none;
}

.side-panel a {
  text-decoration: none;
}

.side-panel .item-meta {
  display: block;
  margin: 0;
}

.chunk-stack {
  display: grid;
  gap: 18px;
}

.lesson-chunk {
  padding: 22px 0;
  border-top: 1px solid var(--line);
}

.lesson-chunk:first-child {
  border-top: 0;
}

.lesson-chunk ul {
  padding-left: 1.25rem;
}

.lesson-chunk table {
  width: 100%;
  border-collapse: collapse;
  margin: 12px 0;
  font-size: 14px;
}

.lesson-chunk th,
.lesson-chunk td {
  border: 1px solid var(--line);
  padding: 8px;
  vertical-align: top;
}

.lesson-chunk tr:first-child {
  background: var(--panel-subtle);
  font-weight: 700;
}

.lesson-chunk pre {
  overflow: auto;
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #1f2428;
  color: #f6f8fa;
}

@media (max-width: 820px) {
  .topbar {
    align-items: flex-start;
    flex-direction: column;
    gap: 8px;
  }

  main {
    padding: 28px 18px 56px;
  }

  .item-row {
    grid-template-columns: 1fr;
  }

  .curriculum-layout {
    grid-template-columns: 1fr;
  }

  .definition-list div {
    grid-template-columns: 1fr;
    gap: 2px;
  }

  .side-panel {
    position: static;
  }
}