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

:root {
  --cream: #f5f0e8;
  --ink: #0d0d0d;
  --ink-muted: #5a5a5a;
  --surface: #fffdf9;
  --surface-2: #faf6ef;
  --border: #0d0d0d;
  --border-soft: rgba(13, 13, 13, 0.12);

  --coral: #ff5c5c;
  --yellow: #ffe14d;
  --teal: #3dd9c4;
  --purple: #a78bfa;
  --pink: #ff8cc8;
  --blue: #4d9fff;
  --gold: #f5a623;

  --radius: 16px;
  --radius-sm: 10px;
  --font-display: "DM Sans", -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-body: "DM Sans", -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: "IBM Plex Mono", "SF Mono", "Fira Code", Consolas, monospace;

  --shadow-hard: 4px 4px 0 var(--ink);
  --shadow-hard-sm: 3px 3px 0 var(--ink);
  --shadow-hover: 6px 6px 0 var(--ink);

  --nav-h: 52px;

  --ink-on-bright: #0d0d0d;
  --invert-bg: #0d0d0d;
  --invert-fg: #f5f0e8;
  --invert-muted: rgba(245, 240, 232, 0.72);
}

[data-theme="dark"] {
  --cream: #12121a;
  --ink: #f5f0e8;
  --ink-muted: #d2d2dc;
  --surface: #1a1a26;
  --surface-2: #222230;
  --border: #f5f0e8;
  --border-soft: rgba(245, 240, 232, 0.22);
  --invert-bg: #0a0a12;
  --invert-fg: #f5f0e8;
  --invert-muted: rgba(245, 240, 232, 0.78);

  --coral: #ff6b6b;
  --yellow: #ffe14d;
  --teal: #3dd9c4;
  --purple: #c4b5fd;
  --pink: #ff8cc8;
  --blue: #6eb3ff;
  --gold: #ffb84d;

  --shadow-hard: 4px 4px 0 rgba(245, 240, 232, 0.25);
  --shadow-hard-sm: 3px 3px 0 rgba(245, 240, 232, 0.2);
  --shadow-hover: 6px 6px 0 rgba(245, 240, 232, 0.3);
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  background: var(--cream);
  color: var(--ink);
  line-height: 1.5;
  overflow-x: hidden;
}

.bg-shapes {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}

.shape {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  opacity: 0.35;
  animation: float 14s ease-in-out infinite;
}

.shape-1 { width: 400px; height: 400px; background: var(--coral); top: 5%; right: 5%; }
.shape-2 { width: 350px; height: 350px; background: var(--yellow); top: 45%; left: -8%; animation-delay: -4s; }
.shape-3 { width: 300px; height: 300px; background: var(--teal); top: 70%; right: -5%; animation-delay: -8s; }
.shape-4 { width: 250px; height: 250px; background: var(--purple); top: 25%; left: 35%; animation-delay: -12s; }

@keyframes float {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33% { transform: translate(25px, -35px) scale(1.06); }
  66% { transform: translate(-20px, 25px) scale(0.94); }
}

.site-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--nav-h);
  padding: 0 clamp(20px, 4vw, 48px);
  background: rgba(245, 240, 232, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 2px solid var(--border);
}

[data-theme="dark"] .site-nav {
  background: rgba(18, 18, 26, 0.88);
}

.nav-logo {
  font-family: var(--font-body);
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--ink);
  text-decoration: none;
  letter-spacing: -0.02em;
}

.nav-logo span {
  color: var(--coral);
}

.nav-links {
  display: flex;
  gap: 28px;
}

.nav-links a {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--ink-muted);
  text-decoration: none;
  transition: color 0.15s;
}

.nav-links a:hover {
  color: var(--ink);
}

.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  background: var(--surface);
  border: 2px solid var(--border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  box-shadow: var(--shadow-hard-sm);
  transition: transform 0.15s, box-shadow 0.15s;
}

.theme-toggle:hover {
  transform: translate(-2px, -2px);
  box-shadow: var(--shadow-hover);
}

.theme-icon {
  font-size: 1.15rem;
  line-height: 1;
}

.section {
  position: relative;
  z-index: 1;
}

.section-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: clamp(48px, 8vw, 96px) clamp(20px, 4vw, 48px);
}

.blog-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 272px;
  gap: 36px;
  align-items: start;
}

.blog-hero {
  padding-top: calc(var(--nav-h) + 36px);
}

.blog-kicker {
  display: inline-block;
  padding: 4px 10px;
  margin-bottom: 12px;
  background: var(--yellow);
  border: 2px solid var(--border);
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--ink-on-bright);
}

.blog-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 18px;
  font-size: 0.8rem;
  color: var(--ink-muted);
  font-weight: 600;
}

.blog-article {
  min-width: 0;
}

.blog-guide {
  position: sticky;
  top: calc(var(--nav-h) + 24px);
  padding: 20px 18px;
  background: var(--surface);
  border: 2px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-hard);
}

.blog-guide-kicker {
  display: inline-block;
  padding: 3px 8px;
  margin-bottom: 10px;
  background: var(--yellow);
  border: 2px solid var(--border);
  border-radius: 999px;
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: #0d0d0d;
}

.blog-guide-title {
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 8px;
}

.blog-guide-desc {
  font-size: 0.86rem;
  line-height: 1.6;
  color: var(--ink-muted);
  margin-bottom: 14px;
}

.blog-guide-cta {
  display: block;
  padding: 11px 12px;
  margin-bottom: 16px;
  background: var(--coral);
  color: #fff;
  border: 2px solid var(--border);
  border-radius: 999px;
  box-shadow: var(--shadow-hard-sm);
  text-align: center;
  text-decoration: none;
  font-weight: 700;
  font-size: 0.88rem;
}

[data-theme="dark"] .blog-guide-cta {
  color: var(--ink);
}

.blog-guide-cta:hover {
  transform: translate(-2px, -2px);
  box-shadow: var(--shadow-hover);
}

.blog-guide-steps {
  list-style: none;
  margin: 0 0 16px;
  padding: 0;
  display: grid;
  gap: 8px;
}

.blog-guide-steps li {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.84rem;
  font-weight: 600;
}

.blog-guide-steps span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 22px;
  height: 22px;
  background: var(--yellow);
  border: 2px solid var(--border);
  border-radius: 999px;
  font-size: 0.72rem;
  color: #0d0d0d;
  flex-shrink: 0;
}

.blog-guide-label {
  margin-bottom: 8px;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--ink-muted);
  text-transform: uppercase;
}

.blog-guide-links {
  display: grid;
  gap: 6px;
  margin-bottom: 14px;
}

.blog-guide-links a {
  color: var(--ink);
  text-decoration: none;
  font-size: 0.86rem;
  font-weight: 600;
}

.blog-guide-links a:hover {
  color: var(--coral);
}

.blog-guide-more {
  display: inline-block;
  font-size: 0.84rem;
  font-weight: 700;
  color: var(--coral);
  text-decoration: none;
}

.blog-guide-more:hover {
  text-decoration: underline;
}

.blog-article-head {
  margin-bottom: 28px;
}

.blog-article h1 {
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  font-weight: 600;
  line-height: 1.2;
  margin: 10px 0 16px;
}

.blog-article-body p {
  font-size: 1.02rem;
  line-height: 1.85;
  color: var(--ink);
  margin-bottom: 18px;
}

.blog-breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 14px;
  font-size: 0.8rem;
  color: var(--ink-muted);
}

.blog-breadcrumb a {
  color: var(--ink-muted);
  text-decoration: none;
  font-weight: 600;
}

.blog-breadcrumb a:hover {
  color: var(--coral);
}

.blog-lead {
  margin: 0 0 24px;
  padding: 16px 18px;
  background: var(--surface);
  border: 2px solid var(--border);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-hard-sm);
}

.blog-lead strong {
  display: block;
  margin-bottom: 8px;
  font-size: 0.82rem;
  letter-spacing: 0.04em;
}

.blog-lead p {
  margin-bottom: 0;
}

.blog-toc {
  margin: 0 0 28px;
  padding: 16px 18px 12px;
  background: var(--surface);
  border: 2px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-hard-sm);
}

.blog-toc-title {
  display: inline-block;
  padding: 3px 8px;
  margin-bottom: 12px;
  background: var(--yellow);
  border: 2px solid var(--border);
  border-radius: 999px;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: #0d0d0d;
}

.blog-article-body .blog-toc-list,
.blog-article-body .blog-toc-list ol {
  list-style: none;
  margin: 0;
  padding: 0;
}

.blog-toc-list {
  counter-reset: toc;
}

.blog-toc-list > li {
  counter-increment: toc;
}

.blog-article-body .blog-toc-list > li > a,
.blog-article-body .blog-toc-list ol a {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 7px 8px;
  margin: 0 -8px;
  border-radius: 8px;
  color: var(--ink);
  text-decoration: none;
  font-weight: 600;
  line-height: 1.45;
}

.blog-article-body .blog-toc-list > li > a::before,
.blog-article-body .blog-toc-list ol a::before {
  flex-shrink: 0;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--ink-muted);
}

.blog-article-body .blog-toc-list > li > a::before {
  content: counter(toc, decimal-leading-zero);
  width: 1.6em;
}

.blog-article-body .blog-toc-list > li > a:hover,
.blog-article-body .blog-toc-list ol a:hover {
  background: var(--surface-2);
  color: var(--coral);
}

.blog-article-body .blog-toc-list ol {
  counter-reset: toc-sub;
  margin: 2px 0 10px 1.7em;
  padding-left: 12px;
  border-left: 2px solid var(--border-soft);
}

.blog-article-body .blog-toc-list ol li {
  counter-increment: toc-sub;
}

.blog-article-body .blog-toc-list ol a {
  padding: 5px 8px;
  font-size: 0.86rem;
  font-weight: 500;
  color: var(--ink-muted);
}

.blog-article-body .blog-toc-list ol a::before {
  content: counter(toc) "." counter(toc-sub);
  width: 2em;
}

.blog-article-body h2,
.blog-article-body h3 {
  scroll-margin-top: calc(var(--nav-h) + 16px);
}

.blog-article-body h2 {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 600;
  margin: 32px 0 12px;
}

.blog-article-body h3 {
  font-family: var(--font-display);
  font-size: 1.08rem;
  font-weight: 600;
  margin: 24px 0 10px;
}

.blog-article-body ul,
.blog-article-body ol {
  margin: 0 0 18px 1.2em;
  color: var(--ink);
  line-height: 1.8;
}

.blog-article-body table {
  width: 100%;
  border-collapse: collapse;
  margin: 0 0 20px;
  font-size: 0.88rem;
  background: var(--surface);
  border: 2px solid var(--border);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-hard-sm);
  overflow: hidden;
}

.blog-article-body {
  overflow-x: auto;
}

.blog-article-body th,
.blog-article-body td {
  padding: 10px 12px;
  text-align: left;
  vertical-align: top;
  border-bottom: 1px solid var(--border-soft);
}

.blog-article-body th {
  background: var(--surface-2);
  font-weight: 700;
}

.blog-article-body tr:last-child td {
  border-bottom: none;
}

.blog-figure {
  margin: 0 0 22px;
  padding: 16px;
  background: var(--surface);
  border: 2px solid var(--border);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-hard-sm);
}

.blog-figure svg {
  display: block;
  width: 100%;
  height: auto;
}

.blog-figure figcaption {
  margin-top: 12px;
  font-size: 0.8rem;
  color: var(--ink-muted);
  font-weight: 600;
}

.blog-callout {
  margin: 0 0 20px;
  padding: 14px 16px;
  background: var(--surface-2);
  border: 2px solid var(--border);
  border-radius: var(--radius-sm);
}

.blog-callout p:last-child {
  margin-bottom: 0;
}

.blog-related {
  display: grid;
  gap: 10px;
  margin: 0 0 8px;
}

.blog-related a {
  display: block;
  padding: 12px 14px;
  background: var(--surface);
  border: 2px solid var(--border);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-hard-sm);
  text-decoration: none;
  color: var(--ink);
  font-weight: 600;
}

.blog-related a:hover {
  transform: translate(-2px, -2px);
  box-shadow: var(--shadow-hover);
}

.blog-article-body a {
  color: var(--coral);
  font-weight: 600;
}


.blog-article-body code {
  font-family: var(--font-mono);
  font-size: 0.88em;
  padding: 1px 6px;
  background: var(--surface-2);
  border: 1px solid var(--border-soft);
  border-radius: 6px;
}

.blog-article-body pre {
  margin: 0 0 20px;
  padding: 16px 18px;
  background: var(--surface);
  border: 2px solid var(--border);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-hard-sm);
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  line-height: 1.65;
}

.blog-back-link {
  display: inline-block;
  margin-bottom: 16px;
  font-weight: 700;
  color: var(--coral);
  text-decoration: none;
}

.blog-back-link:hover {
  text-decoration: underline;
}

.site-footer {
  position: relative;
  z-index: 1;
  background: var(--invert-bg);
  color: var(--invert-fg);
  border-top: 4px solid var(--coral);
}

.footer-bottom {
  max-width: 1100px;
  margin: 0 auto;
  padding: 20px clamp(20px, 4vw, 48px);
  border-top: 1px solid rgba(245, 240, 232, 0.15);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  font-size: 0.8rem;
  color: var(--invert-muted);
}

.footer-actions {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.footer-blog,
.footer-back {
  display: inline-block;
  padding: 8px 20px;
  font-weight: 700;
  font-size: 0.85rem;
  text-decoration: none;
  border: 2px solid var(--cream);
  border-radius: 999px;
  transition: transform 0.15s;
}

.footer-blog {
  background: var(--yellow);
  color: #0d0d0d;
}

.footer-back {
  background: var(--coral);
  color: var(--ink);
}

.footer-blog:hover,
.footer-back:hover {
  transform: translateY(-2px);
}

@media (max-width: 960px) {
  .blog-layout {
    grid-template-columns: 1fr;
  }

  .blog-guide {
    position: static;
    order: 2;
  }
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
  }

  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }
}