/* xls.mom - 小蓝官方下载 */
:root {
  --blue: #2f8fff;
  --blue-dark: #1a6fd4;
  --blue-deep: #0d4a8f;
  --blue-soft: #e8f4ff;
  --blue-mid: #4aabff;
  --ink: #1a2332;
  --muted: #5a6a7a;
  --line: #d8e6f5;
  --bg: #f5f9fd;
  --white: #ffffff;
  --radius: 12px;
  --shadow: 0 8px 28px rgba(26, 111, 212, 0.12);
  --font: "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.75;
  font-size: 16px;
}

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

a {
  color: var(--blue-dark);
  text-decoration: none;
}

a:hover {
  color: var(--blue);
}

.container {
  width: min(1120px, 92%);
  margin: 0 auto;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.96);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(10px);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 64px;
  gap: 16px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  font-weight: 700;
  font-size: 1.05rem;
}

.brand img {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  object-fit: cover;
}

.nav {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.nav a {
  padding: 8px 12px;
  border-radius: 8px;
  color: var(--muted);
  font-size: 0.95rem;
}

.nav a:hover,
.nav a.active {
  color: var(--blue-dark);
  background: var(--blue-soft);
}

.nav-cta {
  background: linear-gradient(135deg, var(--blue-mid), var(--blue-dark)) !important;
  color: #fff !important;
  font-weight: 600;
}

.menu-toggle {
  display: none;
  border: 1px solid var(--line);
  background: var(--white);
  border-radius: 8px;
  padding: 8px 12px;
  cursor: pointer;
  color: var(--ink);
}

/* Hero */
.hero {
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(ellipse at 20% 20%, rgba(74, 171, 255, 0.28), transparent 50%),
    radial-gradient(ellipse at 80% 0%, rgba(47, 143, 255, 0.2), transparent 45%),
    linear-gradient(165deg, #eaf5ff 0%, #f7fbff 45%, #eef6fc 100%);
  padding: 56px 0 48px;
  border-bottom: 1px solid var(--line);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 40px;
  align-items: center;
}

.hero-badge {
  display: inline-block;
  padding: 4px 12px;
  border-radius: 999px;
  background: rgba(47, 143, 255, 0.12);
  color: var(--blue-dark);
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 14px;
}

.hero h1 {
  margin: 0 0 14px;
  font-size: clamp(1.7rem, 3.5vw, 2.45rem);
  line-height: 1.3;
  color: var(--blue-deep);
}

.hero-lead {
  margin: 0 0 24px;
  color: var(--muted);
  font-size: 1.05rem;
  max-width: 36em;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 18px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: 10px;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

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

.btn-primary {
  background: linear-gradient(135deg, var(--blue-mid), var(--blue-dark));
  color: #fff;
  box-shadow: 0 10px 24px rgba(26, 111, 212, 0.28);
}

.btn-primary:hover {
  color: #fff;
}

.btn-ghost {
  background: var(--white);
  color: var(--blue-dark);
  border: 1px solid var(--line);
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  color: var(--muted);
  font-size: 0.9rem;
}

.hero-visual {
  position: relative;
}

.hero-visual img {
  width: 100%;
  max-width: 360px;
  margin: 0 auto;
  border-radius: 20px;
  box-shadow: var(--shadow);
  border: 4px solid #fff;
}

/* Sections */
.section {
  padding: 56px 0;
}

.section-alt {
  background: var(--white);
}

.section-head {
  margin-bottom: 28px;
  max-width: 46em;
}

.section-head h2 {
  margin: 0 0 10px;
  font-size: clamp(1.4rem, 2.5vw, 1.9rem);
  color: var(--blue-deep);
}

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

.prose h2,
.prose h3 {
  color: var(--blue-deep);
  margin-top: 1.6em;
}

.prose p {
  margin: 0 0 1em;
  color: #2c3a4a;
}

.prose ul,
.prose ol {
  padding-left: 1.25em;
  color: #2c3a4a;
}

.prose li {
  margin-bottom: 0.45em;
}

/* Feature grid */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.feature-card {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: 0 4px 16px rgba(13, 74, 143, 0.06);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.feature-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow);
}

.feature-card img {
  width: 100%;
  aspect-ratio: 9 / 16;
  object-fit: cover;
  object-position: top;
  background: #eef5fb;
}

.feature-card .body {
  padding: 16px 18px 20px;
}

.feature-card h3 {
  margin: 0 0 8px;
  font-size: 1.08rem;
  color: var(--blue-deep);
}

.feature-card p {
  margin: 0;
  color: var(--muted);
  font-size: 0.94rem;
}

/* Showcase rows */
.showcase {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 28px;
  align-items: center;
  margin-bottom: 36px;
}

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

.showcase-media img {
  width: 100%;
  max-width: 320px;
  margin: 0 auto;
  border-radius: 16px;
  border: 3px solid #fff;
  box-shadow: var(--shadow);
}

.showcase-text h3 {
  margin: 0 0 12px;
  font-size: 1.35rem;
  color: var(--blue-deep);
}

.showcase-text p {
  margin: 0 0 12px;
  color: #2c3a4a;
}

.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 12px;
}

.tag {
  padding: 4px 10px;
  border-radius: 999px;
  background: var(--blue-soft);
  color: var(--blue-dark);
  font-size: 0.82rem;
}

/* Steps */
.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  counter-reset: step;
}

.step {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 20px;
  position: relative;
}

.step::before {
  counter-increment: step;
  content: counter(step);
  display: inline-flex;
  width: 32px;
  height: 32px;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--blue);
  color: #fff;
  font-weight: 700;
  margin-bottom: 12px;
}

.step h3 {
  margin: 0 0 8px;
  font-size: 1.05rem;
}

.step p {
  margin: 0;
  color: var(--muted);
  font-size: 0.92rem;
}

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

.gallery figure {
  margin: 0;
  background: var(--white);
  border-radius: 12px;
  overflow: hidden;
  border: 1px solid var(--line);
}

.gallery img {
  width: 100%;
  aspect-ratio: 9 / 16;
  object-fit: cover;
  object-position: top;
}

.gallery figcaption {
  padding: 10px 12px;
  font-size: 0.85rem;
  color: var(--muted);
  text-align: center;
}

/* CTA band */
.cta-band {
  background: linear-gradient(135deg, #1a6fd4, #0d4a8f 55%, #163a6b);
  color: #fff;
  padding: 48px 0;
  text-align: center;
}

.cta-band h2 {
  margin: 0 0 10px;
  font-size: 1.7rem;
}

.cta-band p {
  margin: 0 auto 22px;
  max-width: 40em;
  opacity: 0.92;
}

.cta-band .btn-primary {
  background: #fff;
  color: var(--blue-deep);
  box-shadow: none;
}

.cta-band .btn-primary:hover {
  color: var(--blue-dark);
}

/* Page hero (inner) */
.page-hero {
  background: linear-gradient(165deg, #eaf5ff, #f7fbff);
  border-bottom: 1px solid var(--line);
  padding: 40px 0 28px;
}

.page-hero h1 {
  margin: 0 0 10px;
  color: var(--blue-deep);
  font-size: clamp(1.5rem, 3vw, 2rem);
}

.page-hero p {
  margin: 0;
  color: var(--muted);
  max-width: 40em;
}

.breadcrumb {
  margin-bottom: 12px;
  font-size: 0.9rem;
  color: var(--muted);
}

.breadcrumb a {
  color: var(--blue-dark);
}

.content-wrap {
  padding: 40px 0 56px;
}

.content-panel {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px 32px;
  box-shadow: 0 4px 16px rgba(13, 74, 143, 0.05);
}

.toc {
  background: var(--blue-soft);
  border-radius: 10px;
  padding: 16px 18px;
  margin-bottom: 24px;
}

.toc strong {
  display: block;
  margin-bottom: 8px;
  color: var(--blue-deep);
}

.toc a {
  display: inline-block;
  margin: 4px 12px 4px 0;
}

/* Error pages */
.error-page {
  min-height: 70vh;
  display: flex;
  align-items: center;
  text-align: center;
  padding: 48px 0;
}

.error-code {
  font-size: 5rem;
  font-weight: 800;
  color: var(--blue);
  line-height: 1;
  margin: 0 0 12px;
}

/* Footer */
.site-footer {
  background: #0f2a4a;
  color: rgba(255, 255, 255, 0.85);
  padding: 40px 0 24px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 28px;
  margin-bottom: 28px;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 12px;
  color: #fff;
  font-weight: 700;
}

.footer-brand img {
  width: 36px;
  height: 36px;
  border-radius: 8px;
}

.site-footer a {
  color: rgba(255, 255, 255, 0.8);
}

.site-footer a:hover {
  color: #fff;
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.footer-links h4 {
  margin: 0 0 8px;
  color: #fff;
  font-size: 1rem;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  padding-top: 16px;
  font-size: 0.88rem;
  color: rgba(255, 255, 255, 0.65);
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 10px;
}

.internal-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 16px;
  margin-top: 20px;
  padding-top: 16px;
  border-top: 1px dashed var(--line);
  font-size: 0.92rem;
}

/* FAQ */
.faq details {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 14px 18px;
  margin-bottom: 10px;
}

.faq summary {
  cursor: pointer;
  font-weight: 600;
  color: var(--blue-deep);
}

.faq details p {
  margin: 10px 0 0;
  color: var(--muted);
}

/* Mobile */
@media (max-width: 900px) {
  .menu-toggle {
    display: inline-flex;
  }

  .nav {
    display: none;
    position: absolute;
    left: 0;
    right: 0;
    top: 64px;
    background: #fff;
    border-bottom: 1px solid var(--line);
    flex-direction: column;
    align-items: stretch;
    padding: 12px 4%;
    gap: 4px;
  }

  .nav.open {
    display: flex;
  }

  .hero-grid,
  .showcase,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .showcase:nth-child(even) .showcase-media {
    order: 0;
  }

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

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

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

  .content-panel {
    padding: 20px 16px;
  }

  .hero {
    padding: 36px 0 32px;
  }

  .section {
    padding: 40px 0;
  }
}

@media (max-width: 560px) {
  .steps {
    grid-template-columns: 1fr;
  }

  .hero-actions {
    flex-direction: column;
  }

  .btn {
    width: 100%;
  }

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