:root {
  --bg: #f6f7f6;
  --panel: #ffffff;
  --ink: #1c2321;
  --muted: #5f6b66;
  --line: #dfe4e1;
  --accent: #2f6f52;
  --accent-soft: #e8f1ec;
  --warn: #a4560c;
  --warn-soft: #fdf1e3;
  --bad: #9d2f2f;
  --bad-soft: #fbeceb;
  --ok: #2f6f52;
  --radius: 10px;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

header.top {
  background: var(--panel);
  border-bottom: 1px solid var(--line);
  padding: 0 24px;
}
header.top .inner {
  max-width: 1080px; margin: 0 auto;
  display: flex; align-items: center; gap: 20px; min-height: 62px;
  flex-wrap: wrap;
}
header.top .brand { font-weight: 650; letter-spacing: -0.01em; }
header.top .brand small { display: block; color: var(--muted); font-weight: 400; font-size: 12px; }
header.top nav { margin-left: auto; display: flex; gap: 18px; align-items: center; }
header.top nav a { color: var(--muted); text-decoration: none; font-size: 14px; }
header.top nav a:hover, header.top nav a.on { color: var(--accent); }

main { max-width: 1080px; margin: 0 auto; padding: 28px 24px 80px; }
main.narrow { max-width: 720px; }

h1 { font-size: 26px; letter-spacing: -0.02em; margin: 0 0 6px; }
h2 { font-size: 19px; letter-spacing: -0.01em; margin: 32px 0 10px; }
h3 { font-size: 16px; margin: 22px 0 6px; }
p.sub { color: var(--muted); margin: 0 0 24px; }

.panel {
  background: var(--panel); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 20px 22px; margin-bottom: 18px;
}

table { width: 100%; border-collapse: collapse; font-size: 14.5px; }
th, td { text-align: left; padding: 9px 10px; border-bottom: 1px solid var(--line); vertical-align: top; }
th { color: var(--muted); font-weight: 600; font-size: 12.5px; text-transform: uppercase; letter-spacing: 0.04em; }
tr:last-child td { border-bottom: none; }
.scroll { overflow-x: auto; }

.pill {
  display: inline-block; padding: 2px 9px; border-radius: 20px;
  font-size: 12px; font-weight: 600; white-space: nowrap;
}
.pill.complete   { background: var(--accent-soft); color: var(--ok); }
.pill.not_started{ background: #eef0ef; color: var(--muted); }
.pill.due_soon   { background: var(--warn-soft); color: var(--warn); }
.pill.overdue    { background: var(--bad-soft); color: var(--bad); }
.pill.pending_live_qa { background: var(--warn-soft); color: var(--warn); }
.pill.draft      { background: #eceaf5; color: #4a3f7a; }

a.btn, button, input[type=submit] {
  display: inline-block; background: var(--accent); color: #fff; border: 0;
  padding: 9px 16px; border-radius: 8px; font: inherit; font-size: 14.5px;
  font-weight: 550; cursor: pointer; text-decoration: none;
}
a.btn:hover, button:hover { filter: brightness(1.08); }
a.btn.ghost, button.ghost {
  background: transparent; color: var(--accent); border: 1px solid var(--line);
}

label { display: block; font-size: 13.5px; font-weight: 600; margin: 14px 0 4px; }
label .hint { display: block; font-weight: 400; color: var(--muted); font-size: 12.5px; }
input[type=text], input[type=email], input[type=password], input[type=date],
select, textarea {
  width: 100%; padding: 9px 11px; border: 1px solid var(--line);
  border-radius: 8px; font: inherit; font-size: 15px; background: #fff;
}
textarea { min-height: 76px; resize: vertical; }
.grid2 { display: grid; grid-template-columns: 1fr 1fr; gap: 0 18px; }
@media (max-width: 620px) { .grid2 { grid-template-columns: 1fr; } }

.notice {
  border-left: 3px solid var(--accent); background: var(--accent-soft);
  padding: 12px 16px; border-radius: 0 8px 8px 0; margin: 16px 0; font-size: 14.5px;
}
.notice.warn { border-color: var(--warn); background: var(--warn-soft); }
.notice.bad  { border-color: var(--bad);  background: var(--bad-soft); }

.lesson { font-size: 16.5px; }
.lesson h2 { border-top: 1px solid var(--line); padding-top: 26px; }
.lesson h2:first-child { border-top: none; padding-top: 0; }
.lesson em { color: var(--muted); }
.lesson blockquote {
  margin: 18px 0; padding: 12px 18px; border-left: 3px solid var(--warn);
  background: var(--warn-soft); border-radius: 0 8px 8px 0;
}
.lesson table { margin: 16px 0; }
.lesson code { background: #eef0ef; padding: 1px 5px; border-radius: 4px; font-size: 13.5px; }

.q { border-top: 1px solid var(--line); padding: 18px 0; }
.q:first-of-type { border-top: none; }
.q .prompt { font-weight: 550; margin-bottom: 10px; }
.q .opt { display: block; font-weight: 400; margin: 5px 0; font-size: 15px; }
.q .opt input { width: auto; margin-right: 8px; }

.mono { font-family: ui-monospace, "SF Mono", Menlo, monospace; font-size: 13px; }
.muted { color: var(--muted); }
.small { font-size: 13px; }
/* Lesson-by-lesson progress */
.progress-head {
  display: flex; align-items: baseline; justify-content: space-between;
  margin-bottom: 7px;
}
.bar {
  height: 7px; border-radius: 4px; background: var(--line);
  overflow: hidden; margin-bottom: 16px;
}
.bar > span {
  display: block; height: 100%; background: var(--accent);
  border-radius: 4px; transition: width .25s ease;
}
.lesson-nav {
  display: flex; justify-content: space-between; gap: 12px; margin: 22px 0 8px;
}
.lesson-nav .btn { max-width: 46%; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

footer.legal {
  max-width: 1080px; margin: 0 auto; padding: 0 24px 40px;
  color: var(--muted); font-size: 12.5px; border-top: 1px solid var(--line);
  padding-top: 18px;
}