:root {
  --blue: #044d80;
  --blue-deep: #033660;
  --blue-ink: #02243f;
  --red: #ff5447;
  --red-deep: #e63d32;
  --bg: #f3f7fb;
  --bg-alt: #e8f0f7;
  --ink: #0c2236;
  --muted: #5b7186;
  --paper: #ffffff;
  --line: #d4e1ec;
  --accent: var(--red);
  --accent-ink: #ffffff;
  --link: #044d80;
  --code-bg: #02243f;
  --code-ink: #e8f4ff;
  --shadow: 0 16px 40px rgba(4, 77, 128, 0.1);
  --sans: "Outfit", "Segoe UI", sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, Consolas, monospace;
}

* { box-sizing: border-box; }

html, body { margin: 0; padding: 0; }

body {
  min-height: 100vh;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 1.05rem;
  line-height: 1.6;
}

a { color: var(--link); text-underline-offset: 0.18em; }
a:hover { color: var(--red); }

.skip {
  position: absolute;
  left: -999px;
  top: 0;
}

.skip:focus {
  left: 1rem;
  top: 1rem;
  background: var(--paper);
  padding: 0.4rem 0.7rem;
  z-index: 10;
}

.shell {
  width: min(1280px, calc(100% - 2.5rem));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 5;
  background: var(--blue);
  box-shadow: 0 8px 24px rgba(2, 36, 63, 0.18);
}

.header-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  min-height: 4.6rem;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  color: #fff;
}

.logo img {
  height: 30px;
  width: auto;
  display: block;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 1.2rem;
}

.site-nav a {
  text-decoration: none;
  color: rgba(255, 255, 255, 0.88);
  font-weight: 500;
}

.site-nav a:hover { color: #fff; }

.nav-cta {
  background: var(--red);
  color: #fff !important;
  padding: 0.48rem 0.9rem;
  border-radius: 999px;
}

.nav-cta:hover { background: var(--red-deep); }

.nav-toggle {
  display: none;
  border: 1px solid rgba(255, 255, 255, 0.25);
  background: transparent;
  color: #fff;
  padding: 0.4rem 0.7rem;
  font: inherit;
  border-radius: 8px;
}

.hero {
  padding: 4.2rem 0 3.4rem;
  background: var(--blue);
  color: #fff;
}

.hero .lede { color: rgba(255, 255, 255, 0.78); }
.hero .eyebrow { color: #ffb3ad; }

.page, .course-hero { padding: 3.5rem 0 2.5rem; }

.hero-grid, .footer-grid, .meta-row, .lesson-wrap, .card-grid, .list-grid {
  display: grid;
  gap: 1.25rem;
}

.hero-grid { grid-template-columns: 1.3fr 0.9fr; align-items: center; }

.eyebrow, .toc-kicker, .footer-label, .panel-kicker, .chip, .card-meta {
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-size: 0.72rem;
  font-weight: 650;
  color: var(--red);
}

h1, h2, h3 {
  letter-spacing: -0.03em;
  line-height: 1.15;
  margin: 0 0 0.7rem;
}

h1 { font-size: clamp(2.2rem, 5vw, 3.8rem); font-weight: 700; }
h2 { font-size: 1.55rem; }
h3 { font-size: 1.25rem; }

.lede {
  font-size: 1.2rem;
  color: var(--muted);
  max-width: 40rem;
}

.hero-actions, .pager {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin-top: 1.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  text-decoration: none;
  border: 1px solid transparent;
  padding: 0.72rem 1.1rem;
  font-weight: 650;
  border-radius: 999px;
}

.btn-primary {
  background: var(--red);
  color: #fff;
  border-color: var(--red);
}

.btn-primary:hover { background: var(--red-deep); color: #fff; }

.btn-ghost {
  background: transparent;
  color: #fff;
  border-color: rgba(255, 255, 255, 0.35);
}

.btn-ghost:hover { border-color: #fff; color: #fff; }

.page .btn-ghost, .course-hero .btn-ghost {
  color: var(--blue);
  border-color: var(--line);
}

button.btn { font: inherit; cursor: pointer; }

.hero-panel, .card, .list-row, .callout, .contact-form, .toc {
  background: var(--paper);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
}

.hero-panel {
  padding: 1.2rem;
  background: rgba(2, 36, 63, 0.45);
  border-color: rgba(255, 255, 255, 0.12);
  box-shadow: none;
  backdrop-filter: blur(10px);
}

.hero-panel pre, .prose pre {
  background: var(--code-bg);
  color: var(--code-ink);
  padding: 1rem;
  overflow: auto;
  font-family: var(--mono);
  font-size: 0.88rem;
  line-height: 1.5;
  border-radius: 10px;
}

.hero-panel pre { background: #01182c; }

.panel-note, .muted { color: var(--muted); }
.hero-panel .panel-note, .hero-panel .panel-kicker { color: #ffb3ad; }

.band { padding: 2.5rem 0 3.5rem; }
.band-alt { background: var(--bg-alt); }

.section-head {
  display: flex;
  justify-content: space-between;
  align-items: end;
  gap: 1rem;
  margin-bottom: 1.2rem;
}

.card-grid { grid-template-columns: repeat(2, 1fr); }

.card, .list-row {
  text-decoration: none;
  color: inherit;
  padding: 1.2rem 1.25rem;
  border-radius: 14px;
  transition: transform 0.16s ease, border-color 0.16s ease, box-shadow 0.16s ease;
}

.card:hover, .list-row:hover {
  border-color: #9bbcd4;
  transform: translateY(-2px);
  box-shadow: 0 18px 36px rgba(4, 77, 128, 0.14);
}

.chip {
  display: inline-block;
  margin-bottom: 0.6rem;
  color: var(--blue);
}

.card-meta { display: inline-block; margin-top: 0.8rem; color: var(--muted); }

.list-row { display: grid; gap: 0.25rem; }

.prose { max-width: none; }
.lesson-body { min-width: 0; }
.prose :is(p, ul, ol, aside) { margin: 0 0 1rem; }
.prose table {
  width: 100%;
  border-collapse: collapse;
  margin: 0 0 1.25rem;
  font-size: 0.95rem;
}
.prose th, .prose td {
  border: 1px solid var(--line);
  padding: 0.55rem 0.7rem;
  text-align: left;
  vertical-align: top;
}
.prose th { background: var(--bg-alt); }
.prose ul, .prose ol, .outcome-list { padding-left: 1.2rem; }
.prose code, .cmd kbd {
  font-family: var(--mono);
  font-size: 0.88em;
  background: #e4eef6;
  color: var(--blue-deep);
  padding: 0.1em 0.35em;
  border-radius: 4px;
}

.prose pre code { background: none; padding: 0; color: inherit; }

.callout {
  padding: 0.9rem 1rem;
  border-left: 4px solid var(--red);
  border-radius: 0 12px 12px 0;
}

.meta-row { grid-template-columns: 1fr 1fr; margin: 2rem 0; }
.outcome-list { columns: 2; gap: 1.5rem; }

.lesson-index { list-style: none; padding: 0; margin: 0; }
.lesson-index li + li { border-top: 1px solid var(--line); }
.lesson-index a {
  display: grid;
  gap: 0.2rem;
  padding: 0.9rem 0;
  text-decoration: none;
  color: inherit;
}

.lesson-wrap { grid-template-columns: 220px minmax(0, 1fr); gap: 2rem; padding: 2.5rem 0 4rem; align-items: start; }

.toc { padding: 1rem; position: sticky; top: 5.4rem; border-radius: 14px; }
.toc ol { list-style: none; padding: 0; margin: 0 0 1rem; }
.toc li { margin: 0.35rem 0; }
.toc a { text-decoration: none; color: var(--muted); }
.toc .is-current a { color: var(--blue); font-weight: 650; }
.toc-back { font-size: 0.9rem; }

.pager {
  justify-content: space-between;
  border-top: 1px solid var(--line);
  padding-top: 1.2rem;
}

.contact-form { display: grid; gap: 0.8rem; padding: 1.1rem; border-radius: 14px; }
.contact-form label { display: grid; gap: 0.3rem; font-weight: 650; }
.contact-form :is(input, textarea) {
  font: inherit;
  padding: 0.6rem 0.7rem;
  border: 1px solid var(--line);
  background: #f8fbfe;
  border-radius: 8px;
}

.contact-form :is(input, textarea):focus {
  outline: 2px solid color-mix(in srgb, var(--blue) 35%, white);
  border-color: var(--blue);
}

.site-footer {
  background: var(--blue-ink);
  color: #d7e6f2;
  padding: 2.5rem 0 1.2rem;
  margin-top: 2rem;
}

.site-footer a { color: #d7e6f2; display: block; margin: 0.25rem 0; text-decoration: none; }
.site-footer a:hover { color: #fff; }
.site-footer .muted { color: #8eabc2; }
.footer-grid { grid-template-columns: 1.4fr 1fr 1fr; }
.footer-label { color: #ff8d84; }
.footer-base {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  margin-top: 2rem;
  padding-top: 1rem;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  color: #8eabc2;
  font-size: 0.92rem;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  margin-bottom: 0.7rem;
}

.footer-brand img {
  height: 36px;
  width: auto;
  display: block;
}

@media (max-width: 860px) {
  .hero-grid, .card-grid, .meta-row, .lesson-wrap, .footer-grid { grid-template-columns: 1fr; }
  .outcome-list { columns: 1; }
  .toc { position: static; }
  .nav-toggle { display: inline-flex; }
  .site-nav {
    display: none;
    position: absolute;
    inset: 4.6rem 1rem auto;
    background: var(--blue-deep);
    border: 1px solid rgba(255, 255, 255, 0.12);
    padding: 1rem;
    flex-direction: column;
    align-items: start;
    border-radius: 12px;
  }
  .site-nav.is-open { display: flex; }
}