:root {
  --navy-950: #061f39;
  --navy-900: #092a49;
  --navy-800: #0b365f;
  --navy-700: #174d78;
  --cyan-700: #078ca4;
  --cyan-600: #0aa3b8;
  --cyan-200: #a8dbe7;
  --cyan-100: #dff3f7;
  --green-700: #087f73;
  --green-100: #dcf3ef;
  --blue-100: #dff2fb;
  --blue-050: #f4f9fc;
  --ink: #0a2743;
  --muted: #506b82;
  --line: #bad9e7;
  --surface: #ffffff;
  --shadow: 0 20px 54px rgba(6, 45, 77, 0.1);
}

* { box-sizing: border-box; }

html {
  min-height: 100%;
  overflow-x: clip;
  background: var(--blue-050);
}

body {
  min-height: 100vh;
  margin: 0;
  overflow-x: clip;
  color: var(--ink);
  background:
    radial-gradient(circle at 50% 14%, rgba(255, 255, 255, 0.98), rgba(239, 248, 252, 0.78) 36%, transparent 60%),
    linear-gradient(180deg, #fff 0 7%, var(--blue-050) 30% 100%);
  font-family: Inter, Avenir, "Segoe UI", ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
  line-height: 1.5;
}

a { color: inherit; }

.site-header {
  color: #fff;
  background: var(--navy-900);
}

.header-inner,
main,
.footer-inner {
  width: min(1180px, calc(100% - 40px));
  margin: 0 auto;
}

.header-inner {
  display: flex;
  min-height: 112px;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 16px;
  color: #fff;
  text-decoration: none;
}

.brand-logo {
  display: block;
  width: 68px;
  height: 68px;
  object-fit: contain;
}

.brand-copy {
  display: grid;
  min-width: min(300px, 48vw);
}

.brand-copy strong {
  padding-bottom: 5px;
  border-bottom: 2px solid rgba(255, 255, 255, 0.78);
  font-size: clamp(1.35rem, 2.4vw, 1.9rem);
  font-weight: 760;
  line-height: 1.1;
}

.brand-copy span {
  padding-top: 6px;
  color: #b7d6e3;
  font-size: clamp(0.6rem, 1vw, 0.74rem);
  font-weight: 750;
  letter-spacing: 0.11em;
  text-transform: uppercase;
}

.portal-link {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: #d9eef6;
  font-weight: 720;
  text-decoration: none;
}

.portal-link svg,
.card-action svg,
.drive-button svg {
  width: 22px;
  height: 22px;
  fill: none;
  stroke: currentColor;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 2;
}

.portal-link:hover,
.portal-link:focus-visible { color: #fff; }

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.42fr) minmax(300px, 0.58fr);
  min-height: 450px;
  align-items: center;
  gap: 38px;
}

.hero-copy { padding: 62px 0 54px; }

.hero h1 {
  position: relative;
  margin: 0;
  padding-bottom: 25px;
  color: var(--navy-950);
  font-size: clamp(3.1rem, 6vw, 5.7rem);
  font-weight: 830;
  letter-spacing: -0.058em;
  line-height: 0.98;
}

.hero h1::after {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 84px;
  height: 4px;
  background: var(--cyan-600);
  content: "";
}

.hero-lead {
  max-width: 800px;
  margin: 28px 0 0;
  color: #294f6c;
  font-size: clamp(1.3rem, 2.4vw, 1.8rem);
  font-weight: 590;
  line-height: 1.35;
}

.hero-note {
  max-width: 720px;
  margin: 19px 0 0;
  color: var(--muted);
  font-size: 1.03rem;
}

.hero-visual { display: grid; place-items: center; }
.hero-visual svg { width: min(100%, 360px); overflow: visible; }
.circuit { fill: none; stroke: var(--cyan-200); stroke-width: 3; }
.node { fill: var(--cyan-600); opacity: 0.72; }
.page { fill: rgba(255, 255, 255, 0.72); stroke: #8fb8ca; stroke-linejoin: round; stroke-width: 4; }
.page--back { opacity: 0.58; }
.fold { fill: #d7eaf2; stroke: #8fb8ca; stroke-linejoin: round; stroke-width: 4; }
.text-line { fill: none; stroke: #9ab9c8; stroke-linecap: round; stroke-width: 6; }
.scale { fill: none; stroke: var(--navy-700); stroke-linecap: round; stroke-linejoin: round; stroke-width: 5; }

.notebooks { padding: 12px 0 70px; }

.section-heading { margin-bottom: 30px; }
.section-heading h2 { margin: 0; color: var(--navy-950); font-size: clamp(1.8rem, 3vw, 2.45rem); line-height: 1.1; }
.section-heading p { max-width: 770px; margin: 10px 0 0; color: var(--muted); font-size: 1.05rem; }

.notebook-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 22px;
}

.notebook-card {
  display: grid;
  min-height: 274px;
  padding: 28px;
  grid-template-columns: 112px minmax(0, 1fr);
  gap: 26px;
  border: 1px solid var(--line);
  border-radius: 7px;
  background: rgba(255, 255, 255, 0.94);
  box-shadow: var(--shadow);
  text-decoration: none;
  transition: transform 180ms ease, border-color 180ms ease, box-shadow 180ms ease;
}

.notebook-card:hover,
.notebook-card:focus-visible {
  transform: translateY(-4px);
  border-color: var(--cyan-600);
  box-shadow: 0 26px 66px rgba(6, 45, 77, 0.16);
}

.notebook-card:focus-visible,
.drive-button:focus-visible,
.portal-link:focus-visible {
  outline: 4px solid rgba(10, 163, 184, 0.26);
  outline-offset: 4px;
}

.card-icon {
  display: grid;
  width: 112px;
  height: 112px;
  place-items: center;
  border-radius: 6px;
}

.card-icon--blue { color: var(--navy-700); background: var(--blue-100); }
.card-icon--green { color: var(--green-700); background: var(--green-100); }
.card-icon svg { width: 72px; height: 72px; fill: none; stroke: currentColor; stroke-linecap: round; stroke-linejoin: round; stroke-width: 3; }

.card-content { display: flex; min-width: 0; align-items: flex-start; flex-direction: column; }
.card-content > strong { color: var(--navy-950); font-size: clamp(1.35rem, 2.1vw, 1.72rem); font-weight: 810; line-height: 1.12; }
.card-content > span:not(.card-action) { margin-top: 12px; color: var(--muted); font-size: 1rem; line-height: 1.48; }

.card-action {
  display: inline-flex;
  min-height: 46px;
  margin-top: auto;
  padding: 10px 17px;
  align-items: center;
  justify-content: center;
  gap: 11px;
  border-radius: 4px;
  color: #fff;
  background: var(--navy-800);
  font-size: 0.94rem;
  font-weight: 760;
}

.notebook-card:hover .card-action svg,
.notebook-card:focus-visible .card-action svg,
.drive-button:hover svg,
.drive-button:focus-visible svg { transform: translate(3px, -3px); }

.card-action svg,
.drive-button svg { transition: transform 180ms ease; }

.drive-access {
  display: grid;
  margin-bottom: 76px;
  padding: 28px 32px;
  grid-template-columns: 92px minmax(0, 1fr) auto;
  align-items: center;
  gap: 26px;
  border: 1px solid #b8e2d9;
  border-radius: 7px;
  background: linear-gradient(90deg, #e9f8f4, #f5fbfc 70%);
}

.drive-icon { display: grid; width: 92px; height: 92px; place-items: center; border-radius: 6px; background: rgba(255, 255, 255, 0.72); }
.drive-icon svg { width: 64px; height: 64px; }
.drive-green { fill: #18a15f; }
.drive-yellow { fill: #f3b51b; }
.drive-blue { fill: #1676d2; }
.drive-copy { display: grid; gap: 6px; }
.drive-copy strong { color: var(--navy-950); font-size: clamp(1.35rem, 2.3vw, 1.85rem); line-height: 1.15; }
.drive-copy span { color: var(--muted); }

.drive-button {
  display: inline-flex;
  min-height: 54px;
  padding: 13px 22px;
  align-items: center;
  justify-content: center;
  gap: 13px;
  border-radius: 4px;
  color: #fff;
  background: var(--green-700);
  font-weight: 780;
  text-decoration: none;
}

.site-footer { color: #fff; background: var(--navy-900); }
.footer-inner { display: flex; min-height: 145px; align-items: center; justify-content: space-between; gap: 32px; }
.footer-identity { display: grid; gap: 3px; }
.footer-identity strong { font-size: 1.08rem; }
.footer-identity span { color: #a9ccdc; }
.footer-purpose { color: #91c6d8; font-size: 0.78rem; font-weight: 760; letter-spacing: 0.12em; text-transform: uppercase; }
.site-footer a { padding-left: 32px; border-left: 1px solid rgba(121, 202, 221, 0.65); color: #d8edf5; text-decoration: none; }
.site-footer a:hover, .site-footer a:focus-visible { color: #fff; text-decoration: underline; text-underline-offset: 4px; }

@media (max-width: 900px) {
  .hero { grid-template-columns: minmax(0, 1fr) 240px; min-height: 400px; }
  .notebook-card { grid-template-columns: 90px minmax(0, 1fr); gap: 20px; padding: 23px; }
  .card-icon { width: 90px; height: 90px; }
  .card-icon svg { width: 60px; height: 60px; }
  .drive-access { grid-template-columns: 76px minmax(0, 1fr); }
  .drive-icon { width: 76px; height: 76px; }
  .drive-button { grid-column: 2; justify-self: start; }
  .footer-purpose { display: none; }
}

@media (max-width: 720px) {
  .header-inner { padding: 22px 0; align-items: flex-start; flex-direction: column; gap: 16px; }
  .brand-logo { width: 58px; height: 58px; }
  .portal-link { margin-left: 74px; }
  .hero { grid-template-columns: 1fr; min-height: auto; }
  .hero-copy { padding: 52px 0 18px; }
  .hero-visual { display: none; }
  .notebooks { padding-top: 30px; }
  .notebook-grid { grid-template-columns: 1fr; }
  .notebook-card { min-height: 250px; }
  .drive-access { margin-bottom: 54px; }
  .footer-inner { padding: 28px 0; align-items: flex-start; flex-direction: column; }
  .site-footer a { padding: 14px 0 0; border-top: 1px solid rgba(121, 202, 221, 0.65); border-left: 0; }
}

@media (max-width: 480px) {
  .header-inner, main, .footer-inner { width: min(100% - 28px, 1180px); }
  .brand { gap: 12px; }
  .brand-copy { min-width: 0; }
  .brand-copy strong { font-size: 1.3rem; }
  .brand-copy span { font-size: 0.56rem; letter-spacing: 0.075em; }
  .portal-link { margin-left: 0; }
  .hero h1 { font-size: clamp(2.7rem, 15vw, 4rem); }
  .hero-lead { font-size: 1.23rem; }
  .notebook-card { min-height: 0; padding: 24px; grid-template-columns: 1fr; }
  .card-icon { width: 78px; height: 78px; }
  .card-icon svg { width: 54px; height: 54px; }
  .card-content > strong { font-size: 1.42rem; }
  .card-action { width: 100%; margin-top: 24px; }
  .drive-access { padding: 25px; grid-template-columns: 1fr; }
  .drive-button { width: 100%; grid-column: 1; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: 0.01ms !important; }
}