*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    "Helvetica Neue", Arial, "Noto Sans SC", sans-serif;
  line-height: 1.8;
  color: #1a1a1a;
  background: #fff;
  -webkit-font-smoothing: antialiased;
}

a {
  color: #1677ff;
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.site-header {
  border-bottom: 1px solid #eee;
  padding: 16px 0;
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.site-header .brand {
  font-size: 18px;
  font-weight: 700;
  color: #1a1a1a;
  text-decoration: none;
}

.site-header nav a {
  margin-left: 24px;
  font-size: 14px;
  color: #555;
}

.container {
  max-width: 720px;
  margin: 0 auto;
  padding: 0 20px;
}

main {
  padding: 40px 0 60px;
}

article h1 {
  font-size: 28px;
  line-height: 1.4;
  margin-bottom: 12px;
  color: #000;
}

article .meta {
  font-size: 14px;
  color: #888;
  margin-bottom: 32px;
}

article h2 {
  font-size: 22px;
  margin: 36px 0 16px;
  color: #111;
  border-bottom: 1px solid #f0f0f0;
  padding-bottom: 8px;
}

article h3 {
  font-size: 18px;
  margin: 28px 0 12px;
  color: #222;
}

article p {
  margin-bottom: 16px;
  font-size: 16px;
}

article ul,
article ol {
  margin: 0 0 16px 24px;
  font-size: 16px;
}

article li {
  margin-bottom: 8px;
}

article strong {
  color: #000;
}

.blog-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.blog-list li {
  padding: 20px 0;
  border-bottom: 1px solid #f0f0f0;
}

.blog-list li:last-child {
  border-bottom: none;
}

.blog-list a {
  font-size: 18px;
  font-weight: 600;
  color: #1a1a1a;
}

.blog-list a:hover {
  color: #1677ff;
}

.blog-list .desc {
  margin-top: 8px;
  font-size: 14px;
  color: #666;
  line-height: 1.6;
}

/* Breadcrumb */
.breadcrumb {
  font-size: 13px;
  color: #888;
  margin-bottom: 8px;
}

.breadcrumb a {
  color: #888;
}

.breadcrumb a:hover {
  color: #1677ff;
}

.breadcrumb span {
  margin: 0 6px;
  color: #ccc;
}

/* Table of Contents */
.toc {
  background: #f9fafb;
  border: 1px solid #eef0f2;
  border-radius: 8px;
  padding: 20px 24px;
  margin-bottom: 32px;
}

.toc summary {
  font-weight: 600;
  font-size: 15px;
  color: #333;
  cursor: pointer;
  list-style: none;
}

.toc summary::-webkit-details-marker {
  display: none;
}

.toc summary::before {
  content: "▸ ";
  color: #999;
}

.toc[open] summary::before {
  content: "▾ ";
}

.toc ol {
  margin: 12px 0 0 20px;
  padding: 0;
  font-size: 14px;
  line-height: 2;
  color: #555;
}

.toc li {
  margin: 0;
}

.toc a {
  color: #555;
  text-decoration: none;
}

.toc a:hover {
  color: #1677ff;
}

/* Related articles */
.related-articles {
  margin: 40px 0 0;
  padding: 24px;
  background: #fafbfc;
  border-radius: 8px;
}

.related-articles h3 {
  font-size: 16px;
  margin: 0 0 12px;
  color: #333;
}

.related-articles ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.related-articles li {
  margin-bottom: 8px;
  font-size: 14px;
}

.related-articles li::before {
  content: "→ ";
  color: #1677ff;
}

/* FAQ section */
.faq-section {
  margin: 40px 0 0;
}

.faq-section h2 {
  font-size: 20px;
  margin-bottom: 16px;
  border-bottom: none;
  padding-bottom: 0;
}

.faq-section dt {
  font-weight: 600;
  font-size: 15px;
  color: #222;
  margin: 16px 0 6px;
}

.faq-section dd {
  font-size: 15px;
  color: #555;
  margin: 0 0 16px;
  line-height: 1.7;
}

.cta-box {
  margin: 48px 0 0;
  padding: 28px;
  background: #f7f9fc;
  border-radius: 8px;
  text-align: center;
}

.cta-box p {
  margin-bottom: 16px;
  font-size: 15px;
  color: #444;
}

.cta-btn {
  display: inline-block;
  padding: 12px 32px;
  background: #1677ff;
  color: #fff;
  font-size: 16px;
  font-weight: 600;
  border-radius: 6px;
  text-decoration: none;
  transition: background 0.2s;
}

.cta-btn:hover {
  background: #0e5fd8;
  text-decoration: none;
}

.site-footer {
  border-top: 1px solid #eee;
  padding: 24px 0;
  font-size: 13px;
  color: #999;
  text-align: center;
}

@media (max-width: 480px) {
  article h1 {
    font-size: 22px;
  }

  article h2 {
    font-size: 19px;
  }

  .cta-box {
    padding: 20px 16px;
  }
}