:root {
  --bg: #faf6f0;
  --card: #fffdf9;
  --ink: #4a3b2e;
  --muted: #8a7763;
  --faint: #a0907c;
  --line: #eee0cd;
  --accent: #b3543f;
  --accent-dark: #a3472f;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.7 "Microsoft YaHei", "PingFang SC", system-ui, -apple-system, sans-serif;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; display: block; }

a { color: inherit; }

.head,
main,
footer {
  max-width: 1060px;
  margin-left: auto;
  margin-right: auto;
}

/* ---------- 顶栏 ---------- */
.head {
  display: flex;
  align-items: center;
  padding: 22px 28px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  font-weight: 700;
  font-size: 15px;
}

.brand img { width: 34px; height: 34px; border-radius: 9px; }

.brand span { display: flex; flex-direction: column; line-height: 1.25; }

.brand em {
  font-style: normal;
  font-size: 11px;
  font-weight: 400;
  color: var(--faint);
  letter-spacing: 0.5px;
}

/* ---------- Hero ---------- */
main { padding: 0 28px; }

.hero {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  align-items: center;
  gap: 48px;
  padding: 34px 0 56px;
}

.hero h1 {
  margin: 0 0 14px;
  font-size: clamp(34px, 5vw, 48px);
  line-height: 1.18;
  letter-spacing: -0.5px;
  text-wrap: balance;
}

.hero h1 span { color: var(--accent); }

.lead {
  margin: 0 0 26px;
  max-width: 24em;
  font-size: 16px;
  color: var(--muted);
  text-wrap: balance;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 11px 34px;
  border-radius: 11px;
  border: 0;
  background: var(--accent);
  color: #fff;
  font: inherit;
  font-size: 14.5px;
  font-weight: 600;
  text-decoration: none;
  box-shadow: 0 6px 16px rgba(179, 84, 63, 0.22);
  transition: background 0.15s, transform 0.1s;
}

.btn:hover { background: var(--accent-dark); }

.btn:active { transform: translateY(1px); }

.hero-art {
  position: relative;
  display: flex;
  justify-content: center;
}

.hero-art::before {
  content: "";
  position: absolute;
  inset: 8% 10%;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(179, 84, 63, 0.16), rgba(179, 84, 63, 0) 68%);
  filter: blur(6px);
}

.art-card {
  position: relative;
  width: min(380px, 100%);
  aspect-ratio: 1;
  border-radius: 30px;
  background: #fffdf9;
  border: 1px solid var(--line);
  box-shadow: 0 24px 60px rgba(120, 90, 60, 0.14);
  overflow: hidden;
}

.art-card img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: contain;
}

/* 减少动态效果时退回静态帧 */
.art-card img.art-still { display: none; }

@media (prefers-reduced-motion: reduce) {
  .art-card img.art-anim { display: none; }
  .art-card img.art-still { display: block; }
}

/* ---------- 特性 ---------- */
.features { padding-bottom: 40px; }

.grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
}

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 20px 18px;
  transition: transform 0.18s, box-shadow 0.18s;
}

.card:hover {
  transform: translateY(-3px);
  box-shadow: 0 12px 30px rgba(120, 90, 60, 0.1);
}

.card svg {
  width: 24px;
  height: 24px;
  fill: none;
  stroke: var(--accent);
  stroke-width: 1.6;
  stroke-linecap: round;
  stroke-linejoin: round;
  margin-bottom: 10px;
}

.card h3 {
  margin: 0 0 4px;
  font-size: 15px;
}

.card p {
  margin: 0;
  font-size: 13px;
  color: var(--muted);
}

/* ---------- 下载 ---------- */
.download { padding-bottom: 44px; }

.os-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}

.os-card {
  padding: 24px 22px 20px;
  border-radius: 22px;
  background: var(--card);
  border: 1px solid var(--line);
  box-shadow: 0 14px 34px rgba(120, 90, 60, 0.08);
}

.os-card.off { background: #fbf7f1; box-shadow: none; }

.os-head {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 18px;
}

.os-icon {
  width: 26px;
  height: 26px;
  flex: none;
  fill: var(--accent);
}

.os-card.off .os-icon { fill: var(--faint); }

.os-t { min-width: 0; }

.os-t h3 {
  margin: 0;
  font-size: 19px;
  line-height: 1.3;
}

.os-t p {
  margin: 0;
  font-size: 12.5px;
  color: var(--faint);
}

.tag {
  margin-left: auto;
  padding: 2px 10px;
  border-radius: 999px;
  background: #f6e6df;
  color: var(--accent);
  font-size: 11.5px;
  font-weight: 600;
  white-space: nowrap;
}

.os-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  width: 100%;
  margin-bottom: 10px;
  padding: 12px 16px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: #fff;
  color: var(--ink);
  font: inherit;
  font-size: 14.5px;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s, transform 0.1s;
}

.os-btn svg {
  width: 18px;
  height: 18px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.8;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.os-btn:hover { border-color: var(--accent); }

.os-btn:active { transform: translateY(1px); }

.os-btn.primary {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
  box-shadow: 0 6px 16px rgba(179, 84, 63, 0.22);
}

.os-btn.primary:hover { background: var(--accent-dark); border-color: var(--accent-dark); }

.os-btn:disabled {
  opacity: 0.5;
  cursor: default;
  background: transparent;
}

.os-btn:disabled:hover { border-color: var(--line); }

.os-note {
  margin: 4px 0 0;
  font-size: 12px;
  color: var(--faint);
  text-align: center;
}

.note {
  margin: 18px auto 0;
  max-width: 34em;
  text-align: center;
  font-size: 12px;
  line-height: 1.7;
  color: var(--faint);
}

/* ---------- 页脚 ---------- */
footer {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 8px;
  padding: 22px 28px 26px;
  border-top: 1px solid var(--line);
  font-size: 12.5px;
  color: var(--faint);
}

footer img { width: 20px; height: 20px; border-radius: 5px; }

footer .dot { opacity: 0.6; }

/* ---------- 窄屏 ---------- */
@media (max-width: 860px) {
  .hero {
    grid-template-columns: 1fr;
    gap: 34px;
    padding: 24px 0 44px;
  }

  .hero-art { order: -1; }

  .art-card { width: min(320px, 80%); }

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

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

@media (max-width: 560px) {
  .head { padding: 16px 18px; }
  main { padding: 0 18px; }
  .grid { grid-template-columns: 1fr; }
  .os-card { padding: 20px 16px 16px; }
  footer { padding: 20px 18px 24px; }
}