@import url("https://fonts.googleapis.com/css2?family=DM+Serif+Display&family=IBM+Plex+Sans:wght@300;400;500;600&display=swap");
@import url("https://cdn.jsdelivr.net/npm/lxgw-wenkai-webfont@1.7.0/style.css");

:root {
  color-scheme: light;
  --bg: #f7f3ee;
  --bg-accent: #e9dfd1;
  --ink: #1c1b19;
  --muted: #5a5248;
  --accent: #3a6a6f;
  --accent-strong: #254a4d;
  --card: #fbf9f6;
  --shadow: 0 24px 60px rgba(28, 27, 25, 0.12);
  --radius: 24px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "IBM Plex Sans", system-ui, -apple-system, sans-serif;
  background: radial-gradient(circle at 20% 20%, #ffffff 0%, var(--bg) 45%, var(--bg-accent) 100%);
  color: var(--ink);
}

html[lang="zh-Hans"] body {
  font-family: "LXGW WenKai", "IBM Plex Sans", system-ui, -apple-system, sans-serif;
}

.page {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 32px 8vw 24px;
}

.brand {
  font-family: "DM Serif Display", serif;
  font-size: 28px;
  letter-spacing: 0.5px;
}

nav {
  display: flex;
  gap: 16px;
  align-items: center;
}

nav a {
  text-decoration: none;
  color: var(--ink);
  font-weight: 500;
}

.lang {
  display: inline-flex;
  gap: 8px;
  background: var(--card);
  padding: 6px;
  border-radius: 999px;
  box-shadow: var(--shadow);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.lang button {
  border: none;
  background: transparent;
  padding: 6px 12px;
  border-radius: 999px;
  font-weight: 500;
  color: var(--muted);
  cursor: pointer;
}

.lang button.active {
  background: var(--accent);
  color: #fff;
}

main {
  flex: 1;
  padding: 32px 8vw 80px;
  display: grid;
  gap: 64px;
}

.hero {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 32px;
  align-items: center;
}

.hero h1 {
  font-family: "DM Serif Display", serif;
  font-size: clamp(32px, 4vw, 56px);
  margin: 0 0 16px;
}

.hero p {
  font-size: 18px;
  color: var(--muted);
  line-height: 1.6;
  margin: 0 0 24px;
}

.cta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.cta a {
  text-decoration: none;
  padding: 12px 20px;
  border-radius: 999px;
  font-weight: 600;
}

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

.cta a.secondary {
  background: transparent;
  color: var(--accent-strong);
  border: 1px solid var(--accent-strong);
}

.features {
  display: grid;
  gap: 24px;
}

.story {
  display: grid;
  gap: 32px;
}

.story-header h2 {
  font-size: 28px;
  margin: 0 0 8px;
}

.story-header p {
  margin: 0;
  color: var(--muted);
  font-size: 18px;
}

.story-grid {
  display: grid;
  gap: 32px;
}

.story-item {
  display: grid;
  gap: 24px;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  align-items: center;
  background: var(--card);
  padding: 24px;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.story-item:nth-child(even) .story-media {
  order: 2;
}

.story-media img {
  width: 100%;
  height: auto;
  border-radius: 18px;
  display: block;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.25);
}

.story-text h3 {
  margin: 0 0 8px;
  font-size: 22px;
}

.story-text p {
  margin: 0;
  color: var(--muted);
  line-height: 1.6;
}

.features h2,
.download h2 {
  font-size: 28px;
  margin: 0 0 12px;
}

.feature-grid {
  display: grid;
  gap: 16px;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.feature {
  background: var(--card);
  padding: 24px;
  border-radius: 20px;
  box-shadow: var(--shadow);
}

.feature h3 {
  margin: 0 0 8px;
}

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

.assistant {
  background: var(--card);
  padding: 32px;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  display: grid;
  gap: 12px;
}

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

.assistant-grid {
  display: grid;
  gap: 16px;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
}

.download {
  background: var(--card);
  padding: 32px;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  display: grid;
  gap: 12px;
}

.download a {
  width: fit-content;
}

footer {
  padding: 24px 8vw 40px;
  color: var(--muted);
  font-size: 14px;
}

@media (max-width: 720px) {
  header {
    flex-direction: column;
    align-items: flex-start;
    gap: 16px;
  }

  nav {
    flex-wrap: wrap;
  }
}