:root {
  --bg: #f6f4f1;
  --surface: #ffffff;
  --text: #1c1917;
  --muted: #57534e;
  --border: #e7e5e4;
  --accent: #c2410c;
  --accent-dark: #9a3412;
  --accent-soft: #fff7ed;
  --success: #166534;
  --danger: #b91c1c;
  --radius: 16px;
  --shadow: 0 16px 40px rgba(28, 25, 23, 0.06);
}
* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  min-height: 100%;
  display: flex;
  flex-direction: column;
  font-family: "Segoe UI", system-ui, -apple-system, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}
a { color: var(--accent-dark); }
nav {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.85rem 1.5rem;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}
.brand {
  color: var(--text);
  text-decoration: none;
  font-weight: 750;
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  letter-spacing: -0.03em;
}
.logo { height: 36px; width: 36px; display: block; }
.nav-actions { display: flex; align-items: center; gap: 1rem; }
.nav-actions form { margin: 0; }
.nav-actions a { text-decoration: none; color: var(--text); font-weight: 600; }
.container { max-width: 1080px; width: 100%; margin: 0 auto; padding: 2.5rem 1.5rem 4.5rem; flex: 1 0 auto; }
.layout { display: grid; grid-template-columns: minmax(0, 1fr) 320px; gap: 2rem; align-items: start; }
.hero-kicker {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  margin: 0 0 0.8rem;
  padding: 0.25rem 0.65rem;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent-dark);
  font-size: 0.78rem;
  font-weight: 750;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}
h1 {
  margin: 0 0 0.4rem;
  font-size: clamp(2.4rem, 5vw, 3.6rem);
  line-height: 1.05;
  letter-spacing: -0.045em;
}
.byline { margin: 0 0 1rem; color: var(--muted); }
.facts { display: grid; grid-template-columns: repeat(4, 1fr); gap: 0.6rem; margin: 1.4rem 0 0.4rem; }
.facts div { background: var(--surface); border: 1px solid var(--border); border-radius: 12px; padding: 0.7rem 0.8rem; }
.facts dt { font-size: 0.75rem; letter-spacing: 0.04em; text-transform: uppercase; color: var(--muted); }
.facts dd { margin: 0.15rem 0 0; font-weight: 700; }
.syllabus { margin: 0.4rem 0 0; padding: 0; list-style: none; display: grid; gap: 0.65rem; }
.syllabus li { background: var(--surface); border: 1px solid var(--border); border-radius: 12px; padding: 0.85rem 1rem; }
.split { display: grid; grid-template-columns: 1fr 1fr; gap: 0.8rem; }
.split h3 { margin-bottom: 0.35rem; }
.split ul, .plain { margin: 0; padding-left: 1.1rem; }
.plain { display: grid; gap: 0.45rem; }
.enroll { position: sticky; top: 5rem; }
.account-head h1 { font-size: clamp(2rem, 4vw, 2.8rem); margin-bottom: 0.2rem; }
.course-list { list-style: none; margin: 1.25rem 0 0; padding: 0; display: grid; gap: 0.8rem; max-width: 720px; }
.course-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 18px;
  box-shadow: var(--shadow);
  padding: 1.15rem 1.25rem;
  text-decoration: none;
  color: var(--text);
}
.course-card:hover { border-color: #fdba74; }
.course-card strong { display: block; font-size: 1.2rem; letter-spacing: -0.03em; margin-top: 0.15rem; }
.course-card em { display: block; margin-top: 0.2rem; color: var(--muted); font-style: normal; font-size: 0.95rem; }
.price-line { font-size: 2.2rem; font-weight: 800; letter-spacing: -0.03em; margin: 0.4rem 0 1rem; }
.price-now { color: var(--accent, #c2410c); }
.price-line s { color: var(--muted); font-weight: 500; font-size: 0.65em; }
.code-applied { display: block; font-size: 0.85rem; margin-top: 0.2rem; }
.stack-form { display: grid; gap: 0.5rem; margin-bottom: 0.75rem; }
.stack-form button, .stack-form .button { width: 100%; }
.small { font-size: 0.85rem; }
.enroll .error { margin: 0.25rem 0; }
.shop-card,
.account-head + .code-form { max-width: 720px; }
.shop-buy { display: grid; justify-items: end; gap: 0.45rem; }
.empty-note { color: var(--muted); padding: 0.4rem 0; }
.course-go {
  flex: none;
  border-radius: 999px;
  background: var(--text);
  color: #fff;
  font-size: 0.82rem;
  font-weight: 700;
  padding: 0.45rem 0.85rem;
}
.course-path h1 { font-size: clamp(2rem, 4vw, 2.8rem); }
.weeks { list-style: none; margin: 1.4rem 0 0; padding: 0; display: grid; gap: 0.7rem; }
.week {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  align-items: center;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 1rem 1.1rem;
}
.week h2 { margin: 0.15rem 0; font-size: 1.15rem; }
.week p { margin: 0; }
.week .button { width: auto; margin: 0; white-space: nowrap; }
.week.locked { color: var(--muted); background: transparent; }
.hud { font-size: 0.75rem; letter-spacing: 0.04em; text-transform: uppercase; color: var(--muted); margin-bottom: 0.2rem; }
.week.open { border-color: #fdba74; }
h2 { margin: 1.8rem 0 0.45rem; font-size: 1.15rem; letter-spacing: -0.02em; }
.lead { font-size: 1.12rem; max-width: 62ch; margin-top: 0; }
.muted { color: var(--muted); }
.outcomes { list-style: none; padding: 0; margin: 0.4rem 0 0; display: grid; gap: 0.75rem; }
.outcomes li {
  display: grid;
  grid-template-columns: 2rem 1fr;
  gap: 0.75rem;
  align-items: start;
  padding: 0.9rem 1rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 14px;
}
.check {
  width: 2rem;
  height: 2rem;
  display: grid;
  place-items: center;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent-dark);
  font-weight: 800;
}
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1.25rem 1.3rem 1.35rem;
  margin-bottom: 0.9rem;
}
.card h2, .card h3 { margin-top: 0; }
.card .meta { margin: 0.2rem 0 0.9rem; color: var(--muted); font-size: 0.92rem; }
label { display: block; font-weight: 650; margin: 0.8rem 0 0.3rem; }
input, select, textarea {
  width: 100%;
  padding: 0.72rem 0.8rem;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: #fff;
  color: var(--text);
  font: inherit;
}
textarea { min-height: 6rem; resize: vertical; }
.button, button {
  display: inline-block;
  width: 100%;
  text-align: center;
  border: 0;
  border-radius: 10px;
  padding: 0.78rem 1rem;
  margin-top: 0.35rem;
  background: var(--accent);
  color: #fff;
  font: inherit;
  font-weight: 700;
  text-decoration: none;
  cursor: pointer;
}
.nav-actions .button { width: auto; margin: 0; padding: 0.5rem 0.9rem; }
.button:hover, button:hover { background: var(--accent-dark); }
.button.link, button.link { width: auto; margin: 0; padding: 0; color: var(--accent-dark); background: transparent; }
.nav-actions form { display: flex; align-items: center; }
.nav-actions button.link {
  margin: 0;
  padding: 0;
  color: var(--text);
  font-weight: 600;
  line-height: 1.2;
  vertical-align: baseline;
}
.stack { display: grid; gap: 0.8rem; }
.inline { display: flex; flex-wrap: wrap; gap: 0.75rem; align-items: center; }
.notice, .error { border-radius: 12px; padding: 0.75rem 1rem; margin-bottom: 1rem; }
.notice { color: var(--success); background: #dcfce7; }
.error { color: var(--danger); background: #fee2e2; }
.auth { max-width: 460px; margin: 1.5rem auto; }
.auth h1 { font-size: 1.8rem; }
.join {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(280px, 420px);
  gap: 3rem;
  align-items: center;
}
.join h1 { font-size: clamp(2.2rem, 4vw, 3.1rem); }
.join-points { margin: 1.25rem 0 0; padding: 0; list-style: none; display: grid; gap: 0.75rem; }
.join-points li {
  padding-left: 1rem;
  border-left: 3px solid var(--accent);
}
.join-form h2 { margin-top: 0; font-size: 1.45rem; }
.hint { margin: 0.35rem 0 0; color: var(--muted); font-size: 0.82rem; }
.join-alt { margin: 1rem 0 0; color: var(--muted); font-size: 0.95rem; }
@media (max-width: 800px) {
  .join { grid-template-columns: 1fr; gap: 1.5rem; }
}
.code { font-family: ui-monospace, SFMono-Regular, Menlo, monospace; overflow-wrap: anywhere; background: #fafaf9; border-radius: 8px; padding: 0.55rem 0.7rem; }
.generated { padding: 1rem; border: 2px dashed var(--success); border-radius: 12px; }
.flash { border-radius: 12px; padding: 0.75rem 1rem; margin-bottom: 1rem; }
.flash.ok { color: #166534; background: #dcfce7; }
.flash.error { color: var(--danger); background: #fee2e2; }
button.danger { color: var(--danger); }
.row-fields { display: flex; flex-wrap: wrap; gap: 1rem; }
.row-fields > div { flex: 1; min-width: 120px; }
.repo { border-top: 1px solid var(--border); padding-top: 1rem; margin-top: 1rem; }
.admin-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(290px, 1fr)); gap: 1rem; }
table { width: 100%; border-collapse: collapse; font-size: 0.9rem; }
th, td { text-align: left; padding: 0.55rem; border-bottom: 1px solid var(--border); }
footer {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  width: 100%;
  margin-top: auto;
  padding: 1.25rem 1.5rem;
  border-top: 1px solid var(--border);
  background: var(--bg);
  color: var(--muted);
  font-size: 0.92rem;
  box-sizing: border-box;
}
@media (max-width: 800px) {
  nav { padding: 0.85rem 1rem; }
  .layout, .facts, .split { grid-template-columns: 1fr; }
  .enroll { position: static; }
  .week { flex-direction: column; align-items: flex-start; }
  footer { flex-direction: column; }
}