/* Imago 教学软件 · 静态站点样式（无外部依赖，离线可读） */
:root {
  color-scheme: light dark;
  --bg: #faf7f2;
  --ink: #1c1b19;
  --muted: #6b655d;
  --line: #e5ded2;
  --card: #ffffff;
  --accent: #8a5a1b;
  --accent-soft: #f3e8d8;
  --chem: #0f766e;
  --phys: #1d4ed8;
  --math: #b45309;
  --shadow: 0 1px 2px rgba(28, 27, 25, .06), 0 12px 32px rgba(28, 27, 25, .06);
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #1b1917; --ink: #ece7df; --muted: #a9a094; --line: #3a352f;
    --card: #24211e; --accent: #d9a86a; --accent-soft: #2f2a25;
    --shadow: 0 1px 2px rgba(0, 0, 0, .3), 0 12px 32px rgba(0, 0, 0, .25);
  }
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0; color: var(--ink); background: var(--bg);
  font: 16px/1.7 -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB",
        "Microsoft YaHei", "Noto Sans CJK SC", sans-serif;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
img { max-width: 100%; height: auto; display: block; }
.wrap { max-width: 1080px; margin: 0 auto; padding: 0 20px; }

.site-header {
  border-bottom: 1px solid var(--line); background: color-mix(in srgb, var(--bg) 88%, transparent);
  position: sticky; top: 0; z-index: 10; backdrop-filter: blur(12px);
}
.site-header .wrap { display: flex; align-items: center; gap: 18px; min-height: 62px; }
.brand { display: flex; align-items: center; gap: 9px; font-weight: 700; letter-spacing: .02em; color: var(--ink); }
.brand img { width: 28px; height: 28px; border-radius: 7px; }
.site-nav { margin-left: auto; display: flex; gap: 18px; flex-wrap: wrap; font-size: .92rem; }
.site-nav a { color: var(--muted); }
.site-nav a[aria-current="page"] { color: var(--ink); font-weight: 600; }
.lang { font-size: .85rem; border: 1px solid var(--line); padding: 4px 9px; border-radius: 999px; color: var(--muted); }

.hero { padding: 64px 0 44px; }
.hero .eyebrow { color: var(--accent); font-weight: 600; letter-spacing: .08em; font-size: .8rem; text-transform: uppercase; }
.hero h1 { font-size: clamp(2rem, 4.6vw, 3.35rem); line-height: 1.15; margin: .35rem 0 1rem; letter-spacing: -.02em; }
.hero .lead { max-width: 44rem; color: var(--muted); font-size: 1.1rem; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 26px; }
.btn {
  display: inline-flex; align-items: center; gap: 8px; padding: 11px 18px; border-radius: 10px;
  background: var(--ink); color: var(--bg); font-weight: 600; font-size: .95rem;
}
.btn:hover { text-decoration: none; opacity: .88; }
.btn.secondary { background: transparent; color: var(--ink); border: 1px solid var(--line); }
.btn .tag { font-size: .74rem; font-weight: 500; opacity: .7; }

.product-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; padding: 10px 0 28px; }
.product-card {
  background: var(--card); border: 1px solid var(--line); border-radius: 16px; overflow: hidden;
  box-shadow: var(--shadow); display: flex; flex-direction: column;
}
.product-card .shot { aspect-ratio: 4 / 3; overflow: hidden; background: var(--accent-soft); }
.product-card .shot img { width: 100%; height: 100%; object-fit: cover; }
.product-card .body { padding: 18px 18px 20px; display: flex; flex-direction: column; gap: 8px; flex: 1; }
.product-card .title { display: flex; align-items: center; gap: 9px; font-weight: 700; font-size: 1.12rem; }
.product-card .title img { width: 26px; height: 26px; border-radius: 6px; }
.product-card p { margin: 0; color: var(--muted); font-size: .93rem; }
.product-card .more { margin-top: auto; font-size: .9rem; font-weight: 600; }
.badge { display: inline-block; font-size: .72rem; padding: 2px 8px; border-radius: 999px; background: var(--accent-soft); color: var(--accent); font-weight: 600; }
.badge.live { background: #e5f4ee; color: #0f766e; }
.badge.soon { background: #eef2ff; color: #1d4ed8; }

.section { padding: 42px 0; border-top: 1px solid var(--line); }
.section h2 { font-size: 1.55rem; margin: 0 0 8px; letter-spacing: -.01em; }
.section .sub { color: var(--muted); margin: 0 0 24px; }
.values { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
.value { background: var(--card); border: 1px solid var(--line); border-radius: 14px; padding: 18px; }
.value strong { display: block; margin-bottom: 6px; }
.value span { color: var(--muted); font-size: .9rem; }

.product-hero { padding: 48px 0 26px; }
.product-hero .back { font-size: .86rem; color: var(--muted); }
.product-hero .head { display: flex; align-items: center; gap: 16px; margin: 14px 0 10px; }
.product-hero .head img { width: 64px; height: 64px; border-radius: 14px; box-shadow: var(--shadow); }
.product-hero h1 { font-size: clamp(1.8rem, 3.6vw, 2.6rem); margin: 0; letter-spacing: -.02em; }
.product-hero .tagline { color: var(--muted); font-size: 1.08rem; max-width: 48rem; }
.product-hero .meta { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 18px; }

.shots { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; margin: 26px 0 6px; }
.shots figure { margin: 0; background: var(--card); border: 1px solid var(--line); border-radius: 12px; overflow: hidden; }
.shots img { width: 100%; }
.shots figcaption { padding: 9px 12px; font-size: .82rem; color: var(--muted); }

.feature-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 14px 26px; }
.feature { padding: 14px 0; border-top: 1px solid var(--line); }
.feature strong { display: block; margin-bottom: 4px; }
.feature p { margin: 0; color: var(--muted); font-size: .93rem; }

.prose { max-width: 46rem; }
.prose h2 { font-size: 1.15rem; margin: 2.2rem 0 .5rem; }
.prose h3 { font-size: 1rem; margin: 1.4rem 0 .35rem; }
.prose p { margin: .55rem 0; }
.prose ul { padding-left: 1.25rem; }
.prose li { margin: .3rem 0; }
.prose .lead { border-left: 3px solid var(--accent); background: var(--card); padding: .8rem 1rem; border-radius: 0 8px 8px 0; }

.site-footer { border-top: 1px solid var(--line); padding: 28px 0 40px; color: var(--muted); font-size: .88rem; }
.site-footer .wrap { display: flex; flex-wrap: wrap; gap: 16px; align-items: center; }
.site-footer nav { margin-left: auto; display: flex; gap: 16px; flex-wrap: wrap; }
.site-footer a { color: var(--muted); }

@media (max-width: 860px) {
  .product-grid, .values, .shots { grid-template-columns: 1fr 1fr; }
  .feature-grid { grid-template-columns: 1fr; }
}
@media (max-width: 560px) {
  .product-grid, .values, .shots { grid-template-columns: 1fr; }
  .site-header .wrap { min-height: 54px; gap: 10px; }
  .site-nav { gap: 12px; font-size: .86rem; }
  .hero { padding-top: 44px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}