:root {
  --bg: #f5f7fb;
  --bg-soft: rgba(255, 255, 255, 0.84);
  --panel: rgba(255, 255, 255, 0.88);
  --panel-strong: rgba(255, 255, 255, 0.97);
  --border: rgba(35, 50, 90, 0.12);
  --border-strong: rgba(35, 50, 90, 0.18);
  --text: #182033;
  --muted: #4d5a73;
  --muted-2: #66748e;
  --accent: #2563eb;
  --accent-2: #d97706;
  --accent-3: #059669;
  --shadow: 0 18px 60px rgba(34, 48, 86, 0.12);
  --radius: 22px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 11rem;
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--text);
  background:
    radial-gradient(circle at top left, rgba(37, 99, 235, 0.08), transparent 34%),
    radial-gradient(circle at 85% 15%, rgba(217, 119, 6, 0.08), transparent 28%),
    linear-gradient(180deg, #fafcff 0%, #f0f4fb 100%);
  font-family: "Myriad Pro", "Myriad", "Helvetica Neue", "Segoe UI", Arial, sans-serif;
}

.bg-orb {
  position: fixed;
  inset: auto;
  pointer-events: none;
  filter: blur(40px);
  opacity: 0.4;
}

.bg-orb-a {
  width: 20rem;
  height: 20rem;
  top: -5rem;
  left: -6rem;
  background: rgba(37, 99, 235, 0.12);
}

.bg-orb-b {
  width: 18rem;
  height: 18rem;
  right: -4rem;
  top: 15rem;
  background: rgba(217, 119, 6, 0.1);
}

.hero,
.shell {
  width: min(1180px, calc(100% - 2rem));
  margin: 0 auto;
}

.hero {
  padding: 2rem 0 0.9rem;
  display: grid;
  grid-template-columns: minmax(0, 1.55fr) minmax(280px, 0.75fr);
  gap: 1.2rem;
  align-items: start;
}

.hero__copy {
  max-width: 42rem;
}

.eyebrow,
.course-panel__eyebrow {
  margin: 0 0 0.55rem;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  color: var(--accent);
  font-size: 0.74rem;
  font-weight: 700;
}

h1,
h2,
h3 {
  margin: 0;
  font-family: "Myriad Pro", "Myriad", "Helvetica Neue", "Segoe UI", Arial, sans-serif;
  letter-spacing: -0.02em;
}

h1 {
  font-size: clamp(2rem, 4.2vw, 4rem);
  line-height: 1;
  max-width: 14ch;
}

.lede {
  margin: 1rem 0 0;
  color: var(--muted);
  max-width: 54ch;
  font-size: 1.02rem;
  line-height: 1.6;
}

.hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.85rem;
}

.stat {
  border: 1px solid var(--border);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.95), rgba(255, 255, 255, 0.82));
  backdrop-filter: blur(12px);
  border-radius: 18px;
  padding: 1rem;
  box-shadow: var(--shadow);
}

.stat strong {
  display: block;
  font-size: 1.6rem;
  margin-bottom: 0.25rem;
}

.stat span {
  color: var(--muted);
  font-size: 0.94rem;
}

.toolbar {
  position: sticky;
  top: 0.75rem;
  z-index: 20;
  margin-top: 0.25rem;
  padding: 0.9rem;
  border: 1px solid var(--border);
  border-radius: 24px;
  background: rgba(255, 255, 255, 0.82);
  backdrop-filter: blur(18px);
  box-shadow: var(--shadow);
}

.searchbox input {
  width: 100%;
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 0.95rem 1rem;
  color: var(--text);
  background: rgba(255, 255, 255, 0.98);
  outline: none;
  font-size: 0.98rem;
}

.searchbox input:focus {
  border-color: rgba(139, 233, 253, 0.65);
  box-shadow: 0 0 0 4px rgba(139, 233, 253, 0.12);
}

.view-switch {
  margin-top: 0.75rem;
  display: inline-flex;
  gap: 0.5rem;
  padding: 0.35rem;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.8);
}

.view-switch__btn,
.chip,
.card__copy,
.card__link {
  border: 1px solid transparent;
  transition:
    transform 180ms ease,
    border-color 180ms ease,
    background-color 180ms ease,
    color 180ms ease;
}

.view-switch__btn {
  cursor: pointer;
  padding: 0.65rem 0.9rem;
  border-radius: 999px;
  color: var(--muted);
  background: transparent;
  font-weight: 600;
}

.view-switch__btn.is-active {
  color: #ffffff;
  background: linear-gradient(135deg, var(--accent), #4f8cf7);
}

.filter-chip-row {
  margin-top: 0.8rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.bookmark-row {
  margin-top: 0.75rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.category-anchor {
  display: block;
  height: 1px;
  margin-top: -1px;
  scroll-margin-top: 11rem;
}

.course-panel {
  scroll-margin-top: 11rem;
}

.chip {
  cursor: pointer;
  padding: 0.55rem 0.85rem;
  border-radius: 999px;
  color: var(--text);
  background: rgba(255, 255, 255, 0.88);
  border-color: var(--border);
  font-size: 0.9rem;
}

.chip.is-active {
  background: rgba(37, 99, 235, 0.12);
  border-color: rgba(37, 99, 235, 0.32);
  color: var(--accent);
}

.content {
  padding: 1.25rem 0 3rem;
}

.library-grid {
  display: grid;
  gap: 0.95rem;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.card,
.course-panel {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.98), rgba(246, 249, 255, 0.92));
  backdrop-filter: blur(14px);
  box-shadow: var(--shadow);
}

.card {
  padding: 1rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  height: 100%;
}

.card h3 {
  font-size: 1.1rem;
  line-height: 1.25;
}

.card__description {
  margin: 0;
  color: var(--muted);
  font-size: 0.92rem;
  line-height: 1.48;
}

.card__top {
  display: flex;
  gap: 1rem;
  align-items: flex-start;
  justify-content: space-between;
}

.card__copy,
.card__link {
  cursor: pointer;
  border-radius: 12px;
  font-weight: 700;
  text-decoration: none;
}

.card__copy {
  padding: 0.6rem 0.8rem;
  color: var(--text);
  background: rgba(255, 255, 255, 0.9);
  border-color: var(--border);
  white-space: nowrap;
}

.card__link {
  padding: 0.7rem 0.95rem;
  color: #ffffff;
  background: linear-gradient(135deg, var(--accent), #4f8cf7);
}

.card__footer {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  margin-top: auto;
}

.course-panel {
  padding: 1rem;
  margin-bottom: 1rem;
}

.course-panel__header {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  align-items: end;
  padding-bottom: 0.9rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  margin-bottom: 0.95rem;
}

.course-panel__meta {
  color: var(--muted-2);
  font-size: 0.9rem;
  text-align: right;
}

.course-group {
  margin-top: 1rem;
}

.course-group h3 {
  font-size: 1.05rem;
  margin-bottom: 0.75rem;
}

.course-group__empty {
  color: var(--muted-2);
  margin: 0;
  font-size: 0.95rem;
}

.course-grid {
  display: grid;
  gap: 0.85rem;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

.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;
}

.notice {
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 1rem;
  background: rgba(255, 255, 255, 0.9);
  color: var(--muted);
}

.empty-state {
  padding: 2rem 0;
  color: var(--muted);
  text-align: center;
}

@media (max-width: 860px) {
  .hero {
    grid-template-columns: 1fr;
  }

  .hero__stats {
    grid-template-columns: 1fr 1fr;
  }

  .course-panel__header {
    flex-direction: column;
    align-items: start;
  }

  .course-panel__meta {
    text-align: left;
  }
}

@media (max-width: 640px) {
  .hero,
  .shell {
    width: min(100% - 1rem, 1180px);
  }

  .hero {
    padding-top: 1.4rem;
  }

  .hero__stats {
    grid-template-columns: 1fr;
  }

  .card__footer,
  .card__top {
    flex-direction: column;
    align-items: stretch;
  }

  .card__link,
  .card__copy {
    width: 100%;
    text-align: center;
  }
}