:root {
  color-scheme: dark;
  font-family: Inter, "Segoe UI", Arial, sans-serif;
  background: #07111f;
  color: #eef8ff;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-width: 320px;
  background:
    radial-gradient(circle at 18% 5%, rgba(64, 145, 211, .22), transparent 31rem),
    linear-gradient(145deg, #081624, #07111f 58%, #0b1e32);
}

main {
  width: min(1500px, calc(100% - 48px));
  margin: 0 auto;
  padding: 48px 0 72px;
}

header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 32px;
  padding-bottom: 30px;
  border-bottom: 1px solid rgba(151, 210, 249, .2);
}

.eyebrow {
  margin: 0 0 10px;
  color: #6ec9ff;
  font-size: 13px;
  font-weight: 800;
  letter-spacing: .15em;
}

h1 {
  margin: 0;
  font-size: clamp(36px, 5vw, 68px);
  line-height: .95;
  letter-spacing: -.045em;
}

.summary {
  max-width: 760px;
  margin: 20px 0 0;
  color: #b9cad8;
  font-size: 18px;
  line-height: 1.55;
}

.back-link {
  flex: none;
  padding: 11px 15px;
  border: 1px solid rgba(105, 199, 255, .45);
  border-radius: 6px;
  color: #e7f7ff;
  font-size: 14px;
  font-weight: 800;
  text-decoration: none;
}

.back-link:hover { background: rgba(83, 175, 233, .14); }

.library-note {
  display: flex;
  align-items: center;
  gap: 18px;
  margin: 24px 0;
  color: #98afbf;
  font-size: 14px;
}

.library-note strong { color: #eef8ff; letter-spacing: .08em; }

.holiday-icon-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
}

.holiday-icon-card {
  overflow: hidden;
  border: 1px solid rgba(135, 196, 234, .22);
  border-radius: 10px;
  background: rgba(12, 30, 47, .78);
  box-shadow: 0 14px 32px rgba(0, 0, 0, .18);
}

.holiday-icon-preview {
  display: grid;
  height: 225px;
  place-items: center;
  border-bottom: 1px solid rgba(135, 196, 234, .18);
  background:
    radial-gradient(circle at 25% 15%, rgba(255, 255, 255, .16), transparent 55%),
    linear-gradient(145deg, #5d8fbe, #184773 62%, #0a2949);
}

.holiday-icon-preview img {
  display: block;
  width: 82%;
  height: 82%;
  object-fit: contain;
  filter: drop-shadow(0 8px 9px rgba(0, 0, 0, .3));
}

.holiday-icon-details { min-height: 98px; padding: 18px 20px 21px; }
.holiday-icon-details h2 { margin: 0; color: #f7fbff; font-size: 17px; letter-spacing: .04em; }
.holiday-icon-details p { margin: 9px 0 0; color: #9eb3c3; font-size: 14px; line-height: 1.45; }

@media (max-width: 640px) {
  main { width: min(100% - 28px, 1500px); padding-top: 28px; }
  header { display: block; }
  .back-link { display: inline-block; margin-top: 22px; }
  .library-note { align-items: flex-start; flex-direction: column; gap: 5px; }
}