:root {
  --bg: #f6f3ec;
  --surface: #fffdf8;
  --ink: #1f2a27;
  --ink-soft: #55625e;
  --line: #e3ddd0;
  --accent: #2f5d50;
  --accent-ink: #f4efe6;
  --accent-soft: #e2ece6;
  --warn: #9a6a12;
  --ok: #2c7a4b;
  --danger: #a83a2c;
  --radius: 14px;
  --shadow: 0 1px 2px rgba(31, 42, 39, .06), 0 6px 20px rgba(31, 42, 39, .06);
  --font: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-read: Georgia, "Iowan Old Style", "PT Serif", "Times New Roman", serif;
  --mono: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #151b19;
    --surface: #1c2422;
    --ink: #e9e5dc;
    --ink-soft: #a3ada9;
    --line: #2d3734;
    --accent: #7fb9a3;
    --accent-ink: #10201a;
    --accent-soft: #23352f;
    --warn: #e0b45a;
    --ok: #6fcf97;
    --danger: #ef8a7a;
    --shadow: 0 1px 2px rgba(0, 0, 0, .3), 0 6px 20px rgba(0, 0, 0, .25);
  }
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.55 var(--font);
}
a { color: var(--accent); }
h1, h2, h3 { line-height: 1.2; letter-spacing: -0.01em; }
h1 { font-size: clamp(1.7rem, 3.5vw, 2.3rem); margin: .3em 0 .4em; }
:focus-visible { outline: 3px solid var(--accent); outline-offset: 2px; border-radius: 6px; }
main:focus { outline: none; }

.container { max-width: 1080px; margin: 0 auto; padding: 24px 20px 120px; }
.narrow { max-width: 760px; margin: 0 auto; }
.muted { color: var(--ink-soft); }
.meta { color: var(--ink-soft); font-size: .875rem; margin: 0; }
.lead { font-size: 1.125rem; color: var(--ink-soft); max-width: 62ch; }
.visually-hidden { position: absolute !important; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }

/* ---- top bar */
.topbar { background: var(--surface); border-bottom: 1px solid var(--line); position: sticky; top: 0; z-index: 20; }
.topbar__inner { max-width: 1080px; margin: 0 auto; padding: 10px 20px; display: flex; align-items: center; gap: 16px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; color: var(--ink); text-decoration: none; }
.brand__mark { width: 28px; height: 28px; border-radius: 8px; background: var(--accent); position: relative; }
.brand__mark::after { content: ""; position: absolute; inset: 8px 6px 10px; border-top: 3px solid var(--accent-ink); border-bottom: 3px solid var(--accent-ink); }
.user-nav { margin-left: auto; display: flex; align-items: center; gap: 8px; }
.user-nav__login { font-family: var(--mono); font-size: .875rem; color: var(--ink-soft); margin-right: 4px; }
@media (max-width: 520px) { .brand span:last-child { display: none; } .user-nav__login { max-width: 9.5em; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; } }

/* ---- buttons */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  padding: 10px 18px; border-radius: 999px; border: 1px solid transparent;
  font: inherit; font-weight: 600; text-decoration: none; cursor: pointer;
  transition: background .15s, opacity .15s, transform .05s;
}
.btn:active:not(:disabled) { transform: translateY(1px); }
.btn--primary { background: var(--accent); color: var(--accent-ink); }
.btn--primary:hover:not(:disabled) { filter: brightness(1.08); }
.btn--ghost { background: transparent; color: var(--ink); border-color: var(--line); }
.btn--ghost:hover:not(:disabled) { background: var(--accent-soft); }
.btn--sm { padding: 6px 12px; font-size: .875rem; }
.btn--block { width: 100%; }
.btn:disabled { opacity: .45; cursor: not-allowed; }

/* ---- cards & home */
.card { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow); padding: 22px; }
.hero { padding: 28px 0 20px; }
.hero__actions { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 18px; }
.grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 18px; }
.program-card { display: flex; flex-direction: column; gap: 10px; color: inherit; text-decoration: none; transition: transform .15s, border-color .15s; }
.program-card:hover { transform: translateY(-2px); border-color: var(--accent); }
.program-card__title { margin: 0; font-size: 1.3rem; }
.program-card__desc { margin: 0; color: var(--ink-soft); flex: 1; }
.program-card__progress { display: flex; align-items: center; gap: 10px; }
.program-card__progress .progress { flex: 1; }
.program-card__cta { color: var(--accent); font-weight: 600; margin-top: 4px; }
.program-card--done { border-color: color-mix(in srgb, var(--ok) 40%, var(--line)); }

.progress { height: 8px; background: var(--accent-soft); border-radius: 999px; overflow: hidden; }
.progress__fill { display: block; height: 100%; background: var(--accent); border-radius: inherit; transition: width .3s; }

/* ---- program page */
.crumbs { display: flex; flex-wrap: wrap; gap: 6px; align-items: center; font-size: .9rem; margin: 4px 0 8px; color: var(--ink-soft); }
.crumbs a { text-decoration: none; }
.crumbs a:hover { text-decoration: underline; }
.program-status { margin: 18px 0 30px; display: grid; gap: 14px; }
.program-status__row { display: flex; justify-content: space-between; align-items: center; gap: 12px; flex-wrap: wrap; }
.notice { margin: 18px 0 30px; }
.notice h1 { font-size: 1.5rem; margin-top: 0; }
.section { margin: 0 0 26px; }
.section__title { display: flex; align-items: center; gap: 10px; font-size: 1.15rem; margin: 0 0 10px; }
.section__num { display: inline-grid; place-items: center; width: 28px; height: 28px; border-radius: 50%; background: var(--accent-soft); color: var(--accent); font-size: .9rem; }
.lessons { list-style: none; margin: 0; padding: 0; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); overflow: hidden; }
.lesson + .lesson { border-top: 1px solid var(--line); }
.lesson__link { display: flex; align-items: center; gap: 14px; padding: 14px 18px; color: inherit; text-decoration: none; }
a.lesson__link:hover { background: var(--accent-soft); }
.lesson__title { flex: 1; }
.lesson__num { color: var(--ink-soft); margin-right: 6px; font-variant-numeric: tabular-nums; }
.lesson__status { width: 26px; height: 26px; border-radius: 50%; display: inline-grid; place-items: center; font-size: .8rem; flex: none; }
.lesson__status--completed { background: var(--ok); color: #fff; }
.lesson__status--available { background: var(--accent-soft); color: var(--accent); }
.lesson__status--locked { background: transparent; filter: grayscale(1); opacity: .7; }
.lesson--locked .lesson__title { color: var(--ink-soft); }

/* ---- reader */
.reader { max-width: 720px; margin: 0 auto; }
.reader__title { font-size: clamp(1.9rem, 4.5vw, 2.6rem); margin-bottom: .8em; }
.prose { font-family: var(--font-read); font-size: 1.15rem; line-height: 1.75; }
.prose h2 { font-family: var(--font); font-size: 1.4rem; margin: 1.8em 0 .5em; }
.prose h3 { font-family: var(--font); font-size: 1.15rem; margin: 1.5em 0 .4em; }
.prose p, .prose ul, .prose ol { margin: 0 0 1.05em; }
.prose li { margin: .25em 0; }
.prose blockquote { margin: 1.3em 0; padding: .4em 1.1em; border-left: 4px solid var(--accent); background: var(--accent-soft); border-radius: 0 10px 10px 0; }
.prose code { font-family: var(--mono); font-size: .86em; background: var(--accent-soft); padding: .12em .38em; border-radius: 5px; }
.prose pre { background: #1d2624; color: #e8efe9; padding: 16px 18px; border-radius: 12px; overflow-x: auto; line-height: 1.5; font-size: .95rem; }
.prose pre code { background: none; padding: 0; color: inherit; font-size: inherit; }
.prose table { border-collapse: collapse; width: 100%; font-family: var(--font); font-size: .95rem; margin: 0 0 1.2em; }
.prose th, .prose td { border: 1px solid var(--line); padding: 8px 10px; text-align: left; }
.prose th { background: var(--accent-soft); }
.prose img { max-width: 100%; height: auto; }

.end-sentinel { height: 1px; }
.end-card { margin: 34px 0 18px; padding: 20px 22px; border: 1px dashed var(--line); border-radius: var(--radius); text-align: center; }
.end-card__title { font-weight: 700; margin: 0 0 4px; }
.end-card p:last-child { margin-bottom: 0; }
.reader__pager { display: flex; justify-content: space-between; margin-bottom: 20px; }

.readbar { position: fixed; left: 0; right: 0; bottom: 0; z-index: 15; background: color-mix(in srgb, var(--surface) 94%, transparent); backdrop-filter: blur(8px); border-top: 1px solid var(--line); }
.readbar__track { height: 3px; background: var(--accent-soft); }
.readbar__fill { display: block; height: 100%; width: 0; background: var(--accent); transition: width .1s linear; }
.readbar__inner { max-width: 720px; margin: 0 auto; padding: 10px 20px; display: flex; align-items: center; justify-content: space-between; gap: 12px; min-height: 64px; }
.readbar__status { font-size: .92rem; }
.readbar__status--wait { color: var(--ink-soft); }
.readbar__status--ok { color: var(--ok); font-weight: 600; }
.readbar__status--ok::before { content: "✓ "; }
@media (max-width: 520px) { .readbar__inner { flex-direction: column; align-items: stretch; text-align: center; gap: 8px; } }

/* ---- auth */
.auth { display: grid; place-items: center; padding: 30px 0; }
.auth__card { width: 100%; max-width: 440px; }
.auth__card h1 { margin-top: 0; }
.auth__footer { text-align: center; margin: 18px 0 0; color: var(--ink-soft); }
.form { display: grid; gap: 8px; margin-top: 14px; }
.form label { font-weight: 600; font-size: .92rem; margin-top: 8px; }
.form input[type=text], .form input:not([type]), .form input[type=password] {
  font: inherit; padding: 11px 14px; border-radius: 10px; border: 1px solid var(--line);
  background: var(--bg); color: var(--ink);
}
.form input:focus { border-color: var(--accent); outline: none; box-shadow: 0 0 0 3px var(--accent-soft); }
.form .btn--block { margin-top: 12px; }
.form .check { display: flex; gap: 10px; align-items: flex-start; font-weight: 400; margin-top: 12px; }
.form .check input { margin-top: 4px; width: 18px; height: 18px; accent-color: var(--accent); flex: none; }
.form-error { color: var(--danger); margin: 4px 0 0; min-height: 1.2em; font-size: .92rem; }
.form-error:empty { display: none; }
.hint { color: var(--ink-soft); font-size: .85rem; margin: 0; }
.gen-login { background: var(--accent-soft); border-radius: 12px; padding: 14px 16px; display: grid; gap: 6px; }
.gen-login__label { font-size: .8rem; text-transform: uppercase; letter-spacing: .06em; color: var(--ink-soft); }
.gen-login__value { font-family: var(--mono); font-size: 1.3rem; font-weight: 700; color: var(--accent); word-break: break-all; user-select: all; }
.gen-login__actions { display: flex; gap: 8px; }

/* ---- toast */
.toast { position: fixed; left: 50%; bottom: 90px; transform: translate(-50%, 20px); opacity: 0; pointer-events: none;
  background: var(--ink); color: var(--bg); padding: 10px 18px; border-radius: 999px; box-shadow: var(--shadow); transition: .2s; z-index: 30; max-width: 90vw; }
.toast--show { opacity: 1; transform: translate(-50%, 0); }
.toast--error { background: var(--danger); color: #fff; }
.toast--ok { background: var(--ok); color: #fff; }

@media (prefers-reduced-motion: reduce) { * { transition: none !important; } }