:root {
  color-scheme: dark;
  --bg: #02091a;
  --panel: rgba(4, 14, 36, .9);
  --line: rgba(116, 139, 198, .26);
  --text: #f7f9ff;
  --muted: #a9b2ca;
  --purple: #a540d4;
  --blue: #087cf0;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  min-width: 320px;
  min-height: 100vh;
  overflow-x: hidden;
  font-family: "Microsoft YaHei UI", "PingFang SC", system-ui, sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at 50% 35%, rgba(13, 73, 178, .18), transparent 33rem),
    linear-gradient(145deg, #030718, var(--bg) 58%, #04132d);
}
a { color: inherit; }
.page-glow { position: fixed; inset: auto; width: 38rem; height: 38rem; filter: blur(80px); opacity: .18; pointer-events: none; }
.page-glow-left { left: -25rem; top: 32rem; background: #ce22f2; }
.page-glow-right { right: -24rem; top: 26rem; background: #087cf0; }
.topbar {
  position: relative;
  z-index: 2;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
  padding: 0 max(32px, calc((100vw - 1120px) / 2));
  border-bottom: 1px solid var(--line);
  background: rgba(2, 7, 22, .72);
  backdrop-filter: blur(16px);
}
.brand { display: flex; gap: 12px; align-items: center; text-decoration: none; font-size: 26px; font-weight: 700; }
.brand img { width: 40px; height: 40px; object-fit: contain; }
nav { display: flex; height: 100%; gap: 38px; }
nav a { position: relative; display: grid; place-items: center; text-decoration: none; color: var(--muted); font-size: 18px; }
nav a:hover, nav a:focus-visible, nav a.active { color: #fff; }
nav a.active::after { content: ""; position: absolute; bottom: 8px; left: 0; right: 0; height: 2px; background: linear-gradient(90deg, var(--purple), var(--blue)); }
main { position: relative; z-index: 1; width: min(1120px, calc(100% - 40px)); margin: 0 auto; }
.content-grid { display: grid; grid-template-columns: minmax(0, .9fr) minmax(480px, 1.1fr); align-items: center; gap: 54px; min-height: 540px; padding: 30px 0 20px; }
.hero { text-align: center; padding: 18px 0; }
.hero-logo { width: 164px; height: 164px; object-fit: contain; filter: drop-shadow(0 16px 42px rgba(41, 109, 255, .28)); }
h1 { margin: 10px 0 0; font-size: clamp(52px, 6vw, 68px); line-height: 1; letter-spacing: -3px; }
.subtitle { margin: 16px 0; font-size: clamp(21px, 2.5vw, 27px); color: #bdc5d8; }
.features { display: flex; justify-content: center; flex-wrap: wrap; gap: 22px; padding: 0; margin: 22px 0 0; list-style: none; color: #cfd5e4; }
.features li::before { content: "◆"; margin-right: 8px; color: #758dff; }
.download-card {
  padding: 28px 46px 24px;
  text-align: center;
  border: 1px solid rgba(66, 108, 177, .52);
  border-radius: 18px;
  background: linear-gradient(145deg, rgba(7, 17, 42, .94), rgba(2, 10, 27, .94));
  box-shadow: 0 20px 80px rgba(0, 0, 0, .28);
}
.download-icon { margin: -8px 0 2px; color: #a943df; font-size: 48px; font-weight: 300; line-height: 1; }
.download-card h2 { margin: 0; font-size: 30px; }
.platform, .filesize { color: var(--muted); font-size: 16px; }
.platform { margin: 10px 0; }
.divider { height: 1px; margin: 18px 0 14px; background: var(--line); }
.metadata { margin: 0 auto 18px; width: fit-content; text-align: left; }
.metadata div { display: flex; gap: 20px; margin: 6px 0; }
.metadata dt { color: var(--muted); }
.metadata dd { margin: 0; color: #4a89ff; font-weight: 600; }
button { font: inherit; }
.download-button, .confirm-button {
  width: 100%;
  border: 0;
  border-radius: 10px;
  color: #fff;
  cursor: pointer;
  background: linear-gradient(105deg, var(--purple), var(--blue));
  box-shadow: 0 12px 32px rgba(45, 77, 236, .25);
}
.download-button { min-height: 62px; font-size: 22px; font-weight: 700; }
.download-button:disabled { opacity: .45; cursor: wait; }
.windows-mark { margin-right: 9px; font-size: 31px; vertical-align: -3px; }
.filesize { margin: 13px 0 8px; }
.notice { display: flex; align-items: center; gap: 18px; margin-top: 0; padding: 16px 26px; border: 1px solid rgba(162, 61, 214, .72); border-radius: 14px; background: rgba(7, 13, 35, .76); }
.shield { display: grid; place-items: center; flex: 0 0 40px; height: 46px; border: 2px solid #9141db; border-radius: 45% 45% 50% 50%; color: #9141db; font-size: 21px; }
.notice strong { font-size: 17px; }
.notice p { margin: 5px 0 0; color: var(--muted); font-size: 14px; }
footer { padding: 20px 16px 18px; text-align: center; color: #7e8aa5; font-size: 12px; }
footer p { display: inline; margin: 0 10px; }
dialog { width: min(430px, calc(100% - 30px)); border: 1px solid rgba(90, 115, 182, .55); border-radius: 18px; color: var(--text); background: #071026; box-shadow: 0 24px 100px #000; }
dialog::backdrop { background: rgba(0, 4, 16, .78); backdrop-filter: blur(7px); }
dialog form { position: relative; padding: 24px; text-align: center; }
.dialog-close { position: absolute; right: 4px; top: -4px; border: 0; color: #9da8c0; background: transparent; font-size: 30px; cursor: pointer; }
.dialog-icon { display: grid; place-items: center; width: 54px; height: 54px; margin: 0 auto 14px; border-radius: 15px; background: linear-gradient(135deg, var(--purple), var(--blue)); font-size: 28px; font-weight: 800; }
dialog h2 { margin: 0 0 8px; }
dialog p { color: var(--muted); }
#download-code { width: 100%; height: 62px; margin: 14px 0 0; border: 1px solid #435274; border-radius: 10px; outline: 0; color: white; background: #030a19; text-align: center; text-transform: uppercase; font-size: 30px; font-weight: 800; letter-spacing: 12px; }
#download-code:focus { border-color: #798cff; box-shadow: 0 0 0 3px rgba(91, 91, 238, .2); }
.form-message { min-height: 22px; margin: 8px 0; color: #ff8585; }
.confirm-button { min-height: 52px; font-weight: 700; }
.confirm-button:disabled { opacity: .55; cursor: wait; }
.sr-only { position: absolute; width: 1px; height: 1px; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); }
@media (max-width: 640px) {
  .topbar { height: 72px; padding: 0 18px; }
  .brand { font-size: 23px; }
  .brand img { width: 38px; height: 38px; }
  nav { gap: 20px; }
  nav a { font-size: 16px; }
  .hero { padding-top: 46px; }
  .hero-logo { width: 150px; height: 150px; }
  .download-card { padding: 30px 20px; }
  .download-button { min-height: 66px; font-size: 21px; }
  .notice { align-items: flex-start; padding: 22px 20px; }
  footer p { display: block; margin: 7px; }
}
@media (max-width: 900px) {
  main { width: min(680px, calc(100% - 32px)); }
  .content-grid { grid-template-columns: 1fr; gap: 18px; min-height: 0; padding: 34px 0 20px; }
  .hero { padding: 0 0 16px; }
  .hero-logo { width: 140px; height: 140px; }
  .download-card { padding: 30px 28px; }
  .notice { margin-top: 18px; }
  footer { padding: 28px 16px; }
}
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }