/* ============================================================
   数字盐化 · 单页下载落地页
   极简黑白风（参考 Marvis 风格：纯白底 + 纯黑字 + 胶囊按钮）
   ============================================================ */

:root {
  --black: #000000;
  --ink: #111111;
  --gray: #737373;
  --line: #ececec;
  --c-green: #00c853;
  --c-red: #ff1744;
  --c-purple: #6200ea;
  --c-blue: #00b0ff;
  --c-yellow: #ffd600;
  --c-cyan: #00b8d4;
  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  font-family: "PingFang SC", "Microsoft YaHei", "Segoe UI", "Helvetica Neue", Arial, sans-serif;
  background: #ffffff;
  color: var(--ink);
  line-height: 1.7;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

img { max-width: 100%; display: block; }
a { text-decoration: none; color: inherit; }
button { font-family: inherit; cursor: pointer; border: none; background: none; }

.container { width: min(1080px, 90%); margin-inline: auto; }

/* ---------------- 顶部品牌 ---------------- */
.site-top { padding: 28px 0; }
.top-inner { display: flex; align-items: center; justify-content: space-between; }
.brand { display: flex; align-items: center; gap: 11px; color: var(--black); }
.brand-badge {
  width: 38px;
  height: 38px;
  border-radius: 11px;
  object-fit: cover;
  flex-shrink: 0;
  display: block;
}
.brand strong { font-size: 17px; font-weight: 800; letter-spacing: 2.5px; }
.top-slogan { font-size: 13px; color: var(--gray); letter-spacing: 1px; }

/* ---------------- 首屏：标题 + 下载 ---------------- */
.hero-dl {
  text-align: center;
  padding: 76px 0 44px;
}
.dl-eyebrow {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.42em;
  color: var(--gray);
  text-transform: uppercase;
  margin-bottom: 22px;
}
.dl-title {
  font-size: clamp(3.2rem, 11vw, 6.6rem);
  font-weight: 900;
  color: var(--black);
  line-height: 1.08;
  letter-spacing: 0.04em;
}
.dl-sub {
  font-size: clamp(17px, 2.4vw, 22px);
  font-weight: 500;
  color: var(--black);
  margin-top: 14px;
  letter-spacing: 0.06em;
}
.dl-desc {
  font-size: 15px;
  color: var(--gray);
  margin-top: 12px;
  letter-spacing: 0.02em;
}
.dl-desc i {
  font-style: normal;
  margin: 0 10px;
  color: #d4d4d4;
}

/* ---------------- 下载按钮（胶囊） ---------------- */
.dl-btns {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 44px;
}
.dl-btn {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 13px 30px;
  border-radius: 999px;
  border: 1.5px solid var(--black);
  background: #fff;
  color: var(--black);
  font-size: 14.5px;
  font-weight: 600;
  letter-spacing: 0.05em;
  white-space: nowrap;
  transition: all 0.3s var(--ease);
}
.dl-btn svg { width: 18px; height: 18px; flex-shrink: 0; }
/* 手机端短标签（配合媒体查询切换）：微信小程序→小程序、App Store 下载→iOS 下载 */
.w-sm { display: none; }
.dl-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 24px rgba(0, 0, 0, 0.12);
}
.dl-btn.active {
  background: var(--black);
  color: #fff;
}

/* ---------------- 二维码面板 ---------------- */
.qr-panel {
  margin-top: 46px;
  display: flex;
  flex-direction: column;
  align-items: center;
}
.qr-frame {
  width: 188px;
  height: 188px;
  padding: 13px;
  border: 1.5px solid var(--line);
  border-radius: 22px;
  box-shadow: 0 20px 44px rgba(0, 0, 0, 0.08);
  background: #fff;
  transition: box-shadow 0.35s var(--ease), transform 0.35s var(--ease);
}
.qr-frame:hover {
  transform: translateY(-4px);
  box-shadow: 0 26px 54px rgba(0, 0, 0, 0.12);
}
.qr-frame img { width: 100%; height: 100%; object-fit: contain; }
.qr-caption {
  margin-top: 20px;
  font-size: 15px;
  font-weight: 500;
  color: var(--black);
}
.qr-tip {
  margin-top: 6px;
  font-size: 12.5px;
  color: var(--gray);
}

/* ---------------- 场景插画矩阵 ---------------- */
.scenes { padding: 92px 0 36px; }
.scene-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 40px 30px;
}
.scene-card { text-align: center; }
.scene-card img {
  width: 100%;
  aspect-ratio: 1 / 1;
  object-fit: cover;
  border-radius: 24px;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.08);
  background: #fafafa;
  transition: transform 0.4s var(--ease), box-shadow 0.4s var(--ease);
}
.scene-card:hover img {
  transform: translateY(-6px);
  box-shadow: 0 28px 52px rgba(0, 0, 0, 0.13);
}
.scene-card figcaption {
  margin-top: 17px;
  font-size: 14.5px;
  font-weight: 600;
  color: var(--black);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  letter-spacing: 0.08em;
}
.scene-dot { width: 9px; height: 9px; border-radius: 50%; flex-shrink: 0; }

/* ---------------- 底部标语 ---------------- */
.slogan { text-align: center; padding: 96px 0 108px; }
.slogan p {
  font-size: clamp(18px, 2.6vw, 24px);
  font-weight: 600;
  color: var(--black);
  letter-spacing: 0.14em;
}
.slogan small {
  display: block;
  margin-top: 12px;
  font-size: 13px;
  color: var(--gray);
  letter-spacing: 0.1em;
}

/* ---------------- 页脚 ---------------- */
.site-bottom {
  border-top: 1px solid var(--line);
  padding: 26px 0;
  text-align: center;
  font-size: 13px;
  color: var(--gray);
  letter-spacing: 0.03em;
}
.site-bottom i { font-style: normal; margin: 0 8px; color: #d4d4d4; }

/* ---------------- 入场动画 ---------------- */
/* html.js 由 main.js 添加：JS 未加载或加载失败时内容直接可见，不隐藏 */
html.js .reveal {
  opacity: 0;
  transform: translateY(26px);
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
}
html.js .reveal.visible { opacity: 1; transform: translateY(0); }
.reveal-delay-1 { transition-delay: 0.1s; }
.reveal-delay-2 { transition-delay: 0.2s; }

@media (prefers-reduced-motion: reduce) {
  html.js .reveal { opacity: 1; transform: none; transition: none; }
}

/* ---------------- 响应式 ---------------- */
@media (max-width: 720px) {
  .scene-grid { grid-template-columns: repeat(2, 1fr); gap: 30px 18px; }
  .hero-dl { padding-top: 52px; }
  .top-slogan { display: none; }

  /* 手机端：三个下载按钮强制单行，紧凑排布 */
  .dl-btns { flex-wrap: nowrap; gap: 8px; }
  .dl-btn { padding: 11px 14px; font-size: 13px; gap: 6px; letter-spacing: 0.02em; }
  .dl-btn svg { width: 15px; height: 15px; }
  .w-lg { display: none; }
  .w-sm { display: inline; }
}

@media (max-width: 480px) {
  .scene-grid { grid-template-columns: 1fr; gap: 28px; }
  .dl-desc i { margin: 0 6px; }
  .slogan { padding: 72px 0 84px; }
}

@media (max-width: 360px) {
  .dl-btns { gap: 6px; }
  .dl-btn { padding: 10px 11px; font-size: 12.5px; gap: 5px; letter-spacing: 0; }
  .dl-btn svg { width: 14px; height: 14px; }
}