/* Echo 回声 · 使用指南文章页样式(品牌:深蓝 #2b3a67 / 主蓝 #3d5a99 / 浅蓝底 #f0f4fb) */
* { margin: 0; padding: 0; box-sizing: border-box; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  background: #f0f4fb;
  color: #1f2733;
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
}
a { text-decoration: none; }
a, button { touch-action: manipulation; }
a:focus-visible, button:focus-visible {
  outline: 3px solid #7fa3d9;
  outline-offset: 3px;
}

/* 品牌 header */
.blog-head {
  background: #ffffff;
  border-bottom: 1px solid #eef1f6;
  padding: 18px 0;
}
.blog-head-inner {
  max-width: 760px;
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  align-items: center;
  gap: 10px;
}
.blog-head a { display: flex; align-items: center; gap: 10px; }
.blog-logo { width: 30px; height: 30px; }
.blog-brand { font-size: 18px; font-weight: 700; color: #2b3a67; letter-spacing: 0.5px; }

/* 主内容 */
.blog-main {
  max-width: 760px;
  margin: 0 auto;
  padding: 40px 20px 20px;
}
.blog-breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 7px;
  margin-bottom: 16px;
  color: #5f6a7a;
  font-size: 13px;
}
.blog-breadcrumb a { color: #3d5a99; }
.blog-breadcrumb span[aria-hidden="true"] { color: #aab2bf; }
article {
  background: #ffffff;
  border-radius: 16px;
  padding: 40px 44px;
  box-shadow: 0 8px 30px rgba(34, 58, 107, 0.06);
}
.blog-lead { font-size: 16px; color: #354154; }
h1 {
  font-size: 28px;
  line-height: 1.4;
  color: #2b3a67;
  font-weight: 700;
}
.blog-meta {
  font-size: 13px;
  color: #5f6a7a;
  margin: 10px 0 28px;
  padding-bottom: 20px;
  border-bottom: 1px solid #eef1f6;
}
h2 {
  font-size: 20px;
  color: #2b3a67;
  margin: 30px 0 12px;
  font-weight: 700;
}
h3 { font-size: 16px; color: #1f2733; margin: 20px 0 8px; }
p { margin: 12px 0; font-size: 15px; color: #1f2733; }
ul, ol { margin: 12px 0 12px 22px; font-size: 15px; }
li { margin: 6px 0; }
strong { color: #2b3a67; }
article a:not(.blog-cta-btn) {
  color: #31528f;
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}
code {
  background: #eef2fb;
  color: #3d5a99;
  padding: 2px 6px;
  border-radius: 5px;
  font-size: 13px;
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
}

/* 关键要点框 */
.blog-tip {
  background: #f6f9fd;
  border-left: 3px solid #3d5a99;
  border-radius: 8px;
  padding: 14px 18px;
  margin: 18px 0;
  font-size: 14px;
  color: #5f6a7a;
}

/* 参考资料与延伸阅读 */
.blog-sources,
.related-guides {
  margin-top: 32px;
  padding-top: 2px;
}
.blog-sources h2,
.related-guides h2 { margin-top: 0; }
.blog-sources li,
.related-guides li { color: #4a5568; font-size: 14px; }
.blog-sources a,
.related-guides a {
  color: #31528f;
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

/* 指南聚合页 */
.guide-index {
  background: #ffffff;
  border-radius: 16px;
  padding: 40px 44px;
  box-shadow: 0 8px 30px rgba(34, 58, 107, 0.06);
}
.guide-index h1 {
  font-size: 30px;
  line-height: 1.4;
  color: #2b3a67;
}
.guide-index-intro { margin: 12px 0 28px; color: #4a5568; }
.guide-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}
.guide-item {
  display: flex;
  min-height: 190px;
  flex-direction: column;
  border: 1px solid #dfe6f2;
  border-radius: 14px;
  padding: 20px;
  color: #1f2733;
  transition: border-color 0.15s, box-shadow 0.15s, transform 0.15s;
}
.guide-item:hover {
  border-color: #3d5a99;
  box-shadow: 0 8px 22px rgba(34, 58, 107, 0.09);
  transform: translateY(-2px);
}
.guide-item strong { font-size: 17px; line-height: 1.5; }
.guide-item p { flex: 1; margin: 8px 0 14px; color: #5f6a7a; font-size: 14px; }
.guide-item span { color: #3d5a99; font-size: 13px; font-weight: 700; }
.guide-home {
  margin-top: 24px;
  padding: 18px 20px;
  border-radius: 12px;
  background: #eef2fb;
  color: #354154;
  font-size: 14px;
}
.guide-home a { color: #31528f; font-weight: 700; }

/* 底部 CTA */
.blog-cta {
  margin-top: 36px;
  background: linear-gradient(135deg, #2b3a67 0%, #3d5a99 100%);
  border-radius: 14px;
  padding: 28px 30px;
  text-align: center;
}
.blog-cta h3 { color: #ffffff; font-size: 18px; margin: 0 0 8px; }
.blog-cta p { color: #c9d6f0; font-size: 14px; margin: 0 0 18px; }
.blog-cta-btn {
  display: inline-block;
  background: #ffffff;
  color: #2b3a67;
  font-weight: 700;
  font-size: 15px;
  padding: 12px 32px;
  border-radius: 10px;
  letter-spacing: 0.5px;
}

/* footer */
.blog-foot {
  max-width: 760px;
  margin: 0 auto;
  padding: 30px 20px 50px;
  text-align: center;
}
.blog-foot p { font-size: 12px; color: #5f6a7a; margin: 4px 0; }
.blog-foot a { color: #4a5568; }

@media (max-width: 640px) {
  article { padding: 28px 22px; }
  .guide-index { padding: 28px 22px; }
  .guide-grid { grid-template-columns: 1fr; }
  h1 { font-size: 23px; }
  h2 { font-size: 18px; }
  .blog-main { padding-top: 24px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}