:root {
  --blue: #0757bd;
  --blue-deep: #06275e;
  --cyan: #34c9f4;
  --ink: #10254a;
  --muted: #54708f;
  --line: rgba(23, 99, 188, .15);
  font-family: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
}

* { box-sizing: border-box; }
html { min-width: 320px; background: #eaf5ff; }
body { min-width: 320px; min-height: 100vh; margin: 0; color: var(--ink); background: linear-gradient(160deg, #edf8ff 0%, #dceeff 52%, #f8fcff 100%); }
a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; }
h1, h2, p { margin: 0; }

.promo-page { min-height: 100vh; padding: 18px 12px 30px; display: grid; place-items: center; background: radial-gradient(circle at 12% 4%, rgba(52,201,244,.28), transparent 24%), radial-gradient(circle at 96% 78%, rgba(31,96,210,.18), transparent 30%); }
.promo-card { position: relative; overflow: hidden; width: min(100%, 720px); padding: 22px 16px 17px; border: 1px solid rgba(255,255,255,.86); border-radius: 28px; background: linear-gradient(180deg, rgba(255,255,255,.93), rgba(246,251,255,.88)); box-shadow: 0 26px 80px rgba(26, 77, 140, .18); }
.promo-card::before { content: ""; position: absolute; inset: 0; z-index: 0; pointer-events: none; background: linear-gradient(180deg, rgba(238,249,255,.78), rgba(255,255,255,.98) 43%), url('./assets/background/campus-day-mobile.png') center top / cover no-repeat; opacity: .34; }
.promo-card > * { position: relative; z-index: 1; }
.promo-brand { display: flex; align-items: center; gap: 10px; }
.promo-logo { width: 48px; height: 48px; overflow: hidden; border: 3px solid #fff; border-radius: 50%; background: #fff; box-shadow: 0 5px 15px rgba(22,83,170,.18); }
.promo-logo img { width: 100%; height: 100%; object-fit: cover; }
.promo-brand strong, .promo-brand small { display: block; }
.promo-brand strong { color: var(--blue-deep); font-family: Georgia, "Songti SC", serif; font-size: 17px; }
.promo-brand small { margin-top: 2px; color: var(--muted); font-size: 10px; letter-spacing: .12em; }
.promo-hero-copy { padding: 45px 6px 28px; }
.promo-eyebrow { color: var(--blue); font-size: 10px; font-weight: 900; letter-spacing: .15em; }
.promo-hero-copy h1 { margin-top: 13px; color: var(--blue-deep); font-family: Georgia, "Songti SC", serif; font-size: clamp(42px, 13vw, 78px); line-height: .98; letter-spacing: -.06em; }
.promo-hero-copy h1 span { color: var(--blue); }
.promo-hero-copy > p:not(.promo-eyebrow) { max-width: 520px; margin-top: 18px; color: var(--muted); font-size: 14px; line-height: 1.8; }
.promo-actions { display: flex; align-items: center; flex-wrap: wrap; gap: 11px; margin-top: 22px; }
.open-button { display: inline-flex; align-items: center; justify-content: center; gap: 8px; min-height: 44px; padding: 0 18px; color: #fff; border-radius: 999px; background: linear-gradient(120deg, var(--blue), #2187ed); box-shadow: 0 10px 22px rgba(8, 87, 189, .22); font-size: 13px; font-weight: 800; }
.open-button:hover { transform: translateY(-2px); box-shadow: 0 14px 28px rgba(8, 87, 189, .28); }
.promo-note { color: var(--blue); font-size: 11px; font-weight: 800; }
.feature-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 9px; }
.feature-grid article { min-height: 102px; padding: 13px; border: 1px solid var(--line); border-radius: 17px; background: rgba(255,255,255,.75); box-shadow: 0 8px 22px rgba(32,100,170,.06); }
.feature-grid article > span { display: grid; place-items: center; width: 31px; height: 31px; color: #fff; border-radius: 10px; background: linear-gradient(145deg, #1d72dd, #54c8ef); font-size: 12px; font-weight: 900; }
.feature-grid strong, .feature-grid small { display: block; }
.feature-grid strong { margin-top: 10px; color: var(--blue-deep); font-family: Georgia, "Songti SC", serif; font-size: 14px; }
.feature-grid small { margin-top: 4px; color: var(--muted); font-size: 10px; line-height: 1.45; }
.qr-panel { display: flex; align-items: center; justify-content: space-between; gap: 17px; margin-top: 18px; padding: 17px; border: 1px solid rgba(22, 101, 191, .16); border-radius: 21px; background: linear-gradient(120deg, rgba(231,246,255,.92), rgba(255,255,255,.86)); }
.qr-copy { min-width: 0; }
.qr-copy h2 { margin-top: 8px; color: var(--blue-deep); font-family: Georgia, "Songti SC", serif; font-size: clamp(20px, 5vw, 29px); line-height: 1.18; }
.qr-copy > p:not(.promo-eyebrow) { margin-top: 9px; color: var(--muted); font-size: 11px; line-height: 1.6; }
.qr-copy code { display: inline-block; margin-top: 12px; padding: 6px 8px; color: var(--blue); border-radius: 8px; background: rgba(7,87,189,.08); font-size: 10px; }
.qr-frame { display: grid; justify-items: center; flex: none; width: 142px; padding: 8px 8px 7px; border: 1px solid rgba(7,87,189,.14); border-radius: 15px; background: #fff; box-shadow: 0 8px 18px rgba(34,91,150,.12); }
.qr-frame img { width: 124px; height: 124px; image-rendering: auto; }
.qr-frame span { margin-top: 5px; color: var(--blue); font-size: 10px; font-weight: 800; }
.promo-footer { display: flex; justify-content: space-between; gap: 10px; margin-top: 16px; color: #7790a7; font-size: 9px; line-height: 1.5; }

@media (min-width: 620px) {
  .promo-page { padding: 36px 24px; }
  .promo-card { padding: 30px 30px 20px; border-radius: 34px; }
  .promo-hero-copy { padding: 70px 10px 34px; }
  .feature-grid { grid-template-columns: repeat(4, 1fr); gap: 11px; }
  .feature-grid article { min-height: 125px; }
  .qr-panel { padding: 22px; }
  .qr-frame { width: 172px; }
  .qr-frame img { width: 150px; height: 150px; }
}

@media print {
  body, .promo-page { background: #fff; }
  .promo-page { padding: 0; }
  .promo-card { width: 100%; border: 0; box-shadow: none; }
  .promo-card::before { display: none; }
  .open-button { color: var(--blue); border: 1px solid var(--blue); background: #fff; box-shadow: none; }
}