/* 落地页：全屏高度布局 + 全宽内容带与视口对齐的内边距 */
:root {
  --bg: #0f1419;
  --fg: #e8edf2;
  --muted: #9aa7b4;
  --accent: #3d8bfd;
  --card: #181f27;
  --border: #2a3441;
  --pad-x: clamp(1rem, 4vw, 2.5rem);
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  height: 100%;
}

body {
  margin: 0;
  min-height: 100%;
  min-height: 100dvh;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background: radial-gradient(140vw 80vh at 15% -5%, #1a2840, var(--bg)) fixed;
  color: var(--fg);
  line-height: 1.6;
}

/* 整页纵向 flex：首屏铺满视口，底部页脚贴底（内容短时仍可全屏感） */
.page {
  min-height: 100vh;
  min-height: 100dvh;
  width: 100%;
  display: flex;
  flex-direction: column;
}

.hero {
  flex: 1;
  width: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: var(--pad-x);
  padding-top: clamp(2rem, 6vh, 4rem);
  padding-bottom: clamp(2rem, 5vh, 3rem);
}

/* APP 图标：与 public/icon/app_icon.svg 一致，部署为 /app_icon.svg */
.app-icon {
  width: clamp(88px, 18vmin, 140px);
  height: auto;
  aspect-ratio: 1;
  margin-bottom: 1.25rem;
  display: block;
  filter: drop-shadow(0 12px 32px rgba(0, 0, 0, 0.35));
}

.eyebrow {
  letter-spacing: 0.12em;
  text-transform: uppercase;
  font-size: 0.75rem;
  color: var(--muted);
  margin: 0 0 0.5rem;
}

.hero h1 {
  font-size: clamp(1.6rem, 3.6vw + 0.8rem, 2.5rem);
  line-height: 1.2;
  margin: 0 0 1rem;
  max-width: 22ch;
}

.lead {
  margin: 0 0 1.5rem;
  color: var(--muted);
  font-size: clamp(0.95rem, 1.2vw + 0.85rem, 1.1rem);
  max-width: min(40rem, 100%);
}

.cta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 1rem;
  justify-content: center;
}

.cta--row {
  margin-top: 1rem;
}

/* 首屏：Windows / Mac 下载卡片并排（窄屏自动折行） */
.download-cards {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: center;
  max-width: min(44rem, 100%);
  margin: 0 auto 0.5rem;
  text-align: left;
}

.download-card {
  flex: 1 1 14rem;
  max-width: 20rem;
  padding: 1.1rem 1.25rem;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: var(--card);
  text-decoration: none;
  color: var(--fg);
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  transition: border-color 0.15s ease, box-shadow 0.15s ease, transform 0.12s ease;
}

.download-card:hover {
  border-color: rgba(61, 139, 253, 0.55);
  box-shadow: 0 8px 28px rgba(0, 0, 0, 0.25);
  transform: translateY(-2px);
}

.download-card__platform {
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--muted);
}

.download-card__title {
  margin: 0;
  font-size: 1.05rem;
  font-weight: 650;
}

.download-card__meta {
  margin: 0;
  font-size: 0.88rem;
  color: var(--muted);
  line-height: 1.45;
}

.download-card__meta code {
  font-size: 0.82em;
  background: rgba(0, 0, 0, 0.25);
  padding: 0.1em 0.35em;
  border-radius: 4px;
  border: 1px solid var(--border);
}

.download-card__cta {
  margin-top: 0.35rem;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--accent);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.65rem 1.25rem;
  border-radius: 8px;
  font-weight: 600;
  text-decoration: none;
  border: 1px solid transparent;
  font-size: 0.95rem;
}

.btn--primary {
  background: var(--accent);
  color: #fff;
}

.btn--primary:hover {
  filter: brightness(1.08);
}

.btn--ghost {
  border-color: var(--border);
  color: var(--fg);
  background: transparent;
}

.btn--ghost:hover {
  background: rgba(255, 255, 255, 0.06);
}

.hint {
  font-size: 0.85rem;
  color: var(--muted);
  margin: 0;
  max-width: min(36rem, 100%);
}

/* 下方区块：全宽铺陈，仅段落宽度可读性限制 */
.sections {
  width: 100%;
  padding: 0 var(--pad-x) clamp(2.5rem, 6vh, 4rem);
  flex-shrink: 0;
}

.sections section {
  width: 100%;
  max-width: 56rem;
  margin-left: auto;
  margin-right: auto;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.25rem 1.5rem;
  margin-bottom: 1rem;
}

.sections h2 {
  margin: 0 0 0.75rem;
  font-size: 1.15rem;
}

.sections ul {
  margin: 0;
  padding-left: 1.15rem;
  color: var(--muted);
}

.sections p {
  margin: 0;
  color: var(--muted);
}

.footer {
  width: 100%;
  text-align: center;
  padding: 1.5rem var(--pad-x) 2rem;
  font-size: 0.8rem;
  color: var(--muted);
  flex-shrink: 0;
  margin-top: auto;
}

.footer code {
  background: var(--card);
  padding: 0.1rem 0.35rem;
  border-radius: 4px;
  border: 1px solid var(--border);
}

.footer__beian {
  color: var(--muted);
  text-decoration: none;
  border-bottom: 1px solid rgba(154, 167, 180, 0.45);
}

.footer__beian:hover {
  color: var(--fg);
  border-bottom-color: var(--accent);
}