:root {
  color-scheme: light;
  --ink: #152332;
  --muted: #586b7a;
  --blue: #1769e0;
  --blue-dark: #0d47a1;
  --cyan: #eaf5ff;
  --green: #16794a;
  --line: #d8e2ea;
  --paper: #fff;
  --wash: #f6f9fc;
  --code: #10202e;
  --shadow: 0 16px 42px rgba(26, 53, 78, .1);
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; color: var(--ink); background: var(--wash); font: 16px/1.65 Inter, ui-sans-serif, system-ui, sans-serif; }
a { color: var(--blue-dark); }
.wrap { width: min(1120px, calc(100% - 32px)); margin-inline: auto; }
.topbar { position: sticky; top: 0; z-index: 10; background: rgba(255,255,255,.94); border-bottom: 1px solid var(--line); backdrop-filter: blur(12px); }
.topbar .wrap { min-height: 64px; display: flex; align-items: center; justify-content: space-between; gap: 20px; }
.brand { font-weight: 800; text-decoration: none; color: var(--ink); }
nav { display: flex; gap: 18px; }
nav a { text-decoration: none; font-weight: 650; }
.hero { background: radial-gradient(circle at 85% 10%, #d6ecff, transparent 26rem), linear-gradient(145deg, #fff, #eef7ff); border-bottom: 1px solid var(--line); }
.hero .wrap { padding: 70px 0 62px; }
.eyebrow { color: var(--blue); font-weight: 800; letter-spacing: .1em; text-transform: uppercase; }
h1 { max-width: 850px; margin: 10px 0 18px; font-size: clamp(2.3rem, 6vw, 4.8rem); line-height: 1.02; letter-spacing: -.04em; }
h2 { margin-top: 54px; font-size: clamp(1.55rem, 3vw, 2.15rem); }
h3 { margin: 0 0 6px; }
.lead { max-width: 780px; color: #3f5667; font-size: 1.18rem; }
.actions { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 26px; }
.button { display: inline-block; padding: 11px 16px; border-radius: 9px; background: var(--blue); color: #fff; font-weight: 750; text-decoration: none; border: 1px solid var(--blue); }
.button.secondary { background: #fff; color: var(--blue-dark); }
main { padding-bottom: 72px; }
.card-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); gap: 15px; }
.card, .lesson { background: var(--paper); border: 1px solid var(--line); border-radius: 14px; padding: 20px; box-shadow: var(--shadow); }
.card strong { display: block; font-size: 1.45rem; color: var(--blue-dark); }
.lesson { margin: 16px 0; }
.lesson-head { display: flex; justify-content: space-between; align-items: flex-start; gap: 16px; }
.badge { flex: none; border-radius: 999px; padding: 4px 9px; background: #e7f6ed; color: var(--green); font-size: .84rem; font-weight: 800; }
.io { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin: 14px 0; }
pre { margin: 0; padding: 14px; overflow-x: auto; color: #e8f3fc; background: var(--code); border-radius: 9px; font: .9rem/1.55 ui-monospace, SFMono-Regular, Menlo, monospace; }
.io h4 { margin: 0 0 6px; color: var(--muted); font-size: .8rem; letter-spacing: .08em; text-transform: uppercase; }
.downloads { display: flex; flex-wrap: wrap; gap: 9px; margin-top: 14px; }
.download { padding: 7px 10px; border-radius: 7px; background: var(--cyan); border: 1px solid #bddbf3; text-decoration: none; font-weight: 700; }
.callout { margin: 22px 0; padding: 16px 19px; border-left: 5px solid var(--blue); background: #edf6ff; border-radius: 8px; }
table { width: 100%; border-collapse: collapse; background: #fff; }
th, td { padding: 11px 12px; text-align: left; border: 1px solid var(--line); }
th { background: #eef4f8; }
.dashboard { padding-bottom: 88px; }
.section-heading { display: flex; align-items: end; justify-content: space-between; gap: 20px; margin: 58px 0 22px; }
.section-heading h2, .how-it-works h2 { margin: 4px 0 0; }
.section-kicker { color: var(--blue); font-size: .78rem; font-weight: 850; letter-spacing: .12em; text-transform: uppercase; }
.progress-label { color: var(--muted); font-size: .9rem; }
.day-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.day-card { min-height: 420px; overflow: hidden; background: var(--paper); border: 1px solid var(--line); border-radius: 18px; box-shadow: var(--shadow); }
.day-card.available { border-color: #9ac9f2; }
.day-number { display: flex; align-items: baseline; justify-content: space-between; padding: 19px 22px; color: #fff; background: linear-gradient(130deg, #0d47a1, #2385ea); }
.day-number span { font-size: .78rem; font-weight: 800; letter-spacing: .12em; text-transform: uppercase; }
.day-number strong { font-size: 2.5rem; line-height: 1; }
.day-content { display: flex; min-height: 330px; flex-direction: column; padding: 23px; }
.day-content h3 { margin: 10px 0 8px; font-size: 1.3rem; }
.day-content p { margin-top: 0; color: var(--muted); }
.status { align-self: flex-start; padding: 4px 9px; color: #6c7680; background: #edf1f4; border-radius: 999px; font-size: .75rem; font-weight: 800; text-transform: uppercase; }
.status.live { color: var(--green); background: #e7f6ed; }
.topic-list { display: flex; flex-wrap: wrap; gap: 6px; margin: 4px 0 18px; padding: 0; list-style: none; }
.topic-list li { padding: 4px 8px; color: var(--blue-dark); background: var(--cyan); border-radius: 6px; font-size: .82rem; font-weight: 700; }
.day-meta { display: flex; justify-content: space-between; gap: 8px; margin-top: auto; padding-top: 15px; color: var(--muted); border-top: 1px solid var(--line); font-size: .85rem; }
.card-link { display: flex; justify-content: space-between; margin: 18px -23px -23px; padding: 15px 23px; color: #fff; background: var(--blue); font-weight: 800; text-decoration: none; }
.card-link:hover { background: var(--blue-dark); }
.day-card.coming { opacity: .72; box-shadow: none; }
.day-card.coming .day-number { color: #586b7a; background: #e7edf2; }
.how-it-works { display: grid; grid-template-columns: .75fr 2fr; gap: 45px; margin-top: 72px; padding: 38px; background: #eaf5ff; border-radius: 20px; }
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; }
.steps article { padding: 18px; background: #fff; border-radius: 12px; }
.steps article > span { display: grid; width: 30px; height: 30px; place-items: center; color: #fff; background: var(--blue); border-radius: 50%; font-weight: 800; }
.steps h3 { margin-top: 12px; }
.steps p { margin-bottom: 0; color: var(--muted); font-size: .9rem; }
.lesson-hero { background: linear-gradient(145deg, #fff, #eef7ff); border-bottom: 1px solid var(--line); }
.lesson-hero .wrap { padding: 40px 0 50px; }
.lesson-hero h1 { font-size: clamp(2.2rem, 5vw, 4.2rem); }
.back-link { display: inline-block; margin-bottom: 28px; font-weight: 750; text-decoration: none; }
.lesson-page { padding-bottom: 72px; }
footer { padding: 30px 0; border-top: 1px solid var(--line); color: var(--muted); }
@media (max-width: 900px) { .day-grid { grid-template-columns: 1fr 1fr; } .how-it-works { grid-template-columns: 1fr; } }
@media (max-width: 720px) { nav { display: none; } .io, .day-grid, .steps { grid-template-columns: 1fr; } .hero .wrap { padding-top: 48px; } .section-heading { align-items: start; flex-direction: column; } .how-it-works { padding: 24px; } .day-card { min-height: auto; } }