:root {
  --color-bg: #ffffff;
  --color-bg-subtle: #f4f6f8;
  --color-text: #0e1b3d;
  --color-text-muted: #5b6577;
  --color-border: #e2e6ec;
  --color-navy: #0e1b3d;
  --color-accent: #139e8c;
  --color-accent-contrast: #ffffff;
  --color-card-bg: #ffffff;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-mono: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
  --max-width: 980px;
  --radius: 14px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --color-bg: #0b1226;
    --color-bg-subtle: #121b38;
    --color-text: #f0f2f6;
    --color-text-muted: #a7afc2;
    --color-border: #243056;
    --color-navy: #0e1b3d;
    --color-accent: #22c3ac;
    --color-accent-contrast: #0b1226;
    --color-card-bg: #121b38;
  }
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-sans);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

a:hover {
  text-decoration: underline;
}

.wrapper {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* Header */
.site-header {
  border-bottom: 1px solid var(--color-border);
}

.site-header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 18px;
  padding-bottom: 18px;
}

.site-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--color-text);
}

.site-brand:hover {
  text-decoration: none;
}

.site-brand-mark {
  display: block;
  width: 32px;
  height: 32px;
  border-radius: 8px;
}

.site-header-right {
  display: flex;
  align-items: center;
  gap: 20px;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 24px;
}

.site-nav a {
  color: var(--color-text-muted);
  font-size: 0.95rem;
}

.site-nav a:hover {
  color: var(--color-text);
}

.nav-trigger {
  display: none;
}

.nav-toggle {
  display: none;
  cursor: pointer;
  padding: 8px;
  margin: -8px;
}

.nav-toggle svg {
  fill: var(--color-text);
}

.site-lang-switch {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 5px 10px;
  border-radius: 999px;
  color: var(--color-text-muted);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  transition: background 0.15s ease, color 0.15s ease;
}

.site-lang-switch:hover {
  text-decoration: none;
  background: var(--color-bg-subtle);
  color: var(--color-text);
}

.site-lang-switch svg {
  flex-shrink: 0;
}

/* Hero */
.hero {
  padding: 64px 0 40px;
  background: linear-gradient(180deg, var(--color-navy), #16275a 60%, var(--color-bg));
  border-bottom: 1px solid var(--color-border);
  color: #fff;
}

.hero-title,
.hero-subtitle {
  color: #fff;
}

.hero-subtitle {
  opacity: 0.85;
}

.hero-eyebrow {
  margin: 0 0 8px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-size: 0.8rem;
  font-weight: 700;
  color: #22c3ac;
}

.hero-title {
  margin: 0 0 14px;
  font-size: clamp(2rem, 4vw, 3rem);
  line-height: 1.1;
  font-weight: 800;
}

.hero-subtitle {
  margin: 0;
  max-width: 560px;
  color: var(--color-text-muted);
  font-size: 1.05rem;
}

/* Sections */
.section {
  padding: 48px 0;
}

.section-title {
  margin: 0 0 24px;
  font-size: 1.5rem;
  font-weight: 700;
}

.section-header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
}

.section-header .section-title {
  margin-bottom: 0;
}

.section-link {
  font-size: 0.92rem;
  font-weight: 600;
  white-space: nowrap;
}

/* Extension cards */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
}

.ext-card {
  display: block;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--color-card-bg);
  color: var(--color-text);
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.ext-card:hover {
  text-decoration: none;
  transform: translateY(-3px);
  box-shadow: 0 10px 24px rgba(0, 0, 0, 0.08);
}

.ext-card-top {
  height: 72px;
  display: flex;
  align-items: flex-end;
  justify-content: flex-end;
  padding: 12px 16px;
  background: linear-gradient(135deg, var(--color-navy), #1b2c5c);
}

.ext-card-badge {
  background: rgba(34, 195, 172, 0.2);
  color: #22c3ac;
  font-weight: 700;
  font-size: 0.78rem;
  padding: 4px 10px;
  border-radius: 999px;
}

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

.ext-card-category {
  margin: 0 0 6px;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--color-text-muted);
}

.ext-card-name {
  margin: 0 0 8px;
  font-size: 1.15rem;
  font-weight: 700;
}

.ext-card-summary {
  margin: 0;
  color: var(--color-text-muted);
  font-size: 0.92rem;
}

/* Archive */
.archive-year {
  margin-bottom: 8px;
}

.archive-year-title {
  margin: 32px 0 4px;
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--color-text-muted);
}

.archive-year:first-child .archive-year-title {
  margin-top: 0;
}

/* Post list */
.post-list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--color-border);
}

.post-list-item {
  border-bottom: 1px solid var(--color-border);
}

.post-list-item a {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
  padding: 16px 0;
  color: var(--color-text);
}

.post-list-item a:hover {
  text-decoration: none;
  color: var(--color-accent);
}

.post-list-title {
  font-weight: 600;
}

.post-list-date {
  flex-shrink: 0;
  color: var(--color-text-muted);
  font-size: 0.88rem;
}

/* Page & post content */
.page,
.post {
  padding-top: 48px;
  padding-bottom: 48px;
}

.page-title {
  font-size: 2rem;
  font-weight: 800;
  margin: 0 0 24px;
}

.post-header {
  margin-bottom: 24px;
}

.post-meta {
  color: var(--color-text-muted);
  font-size: 0.9rem;
  margin: 0 0 8px;
}

.post-category {
  margin-left: 10px;
  padding: 2px 8px;
  border-radius: 999px;
  background: var(--color-bg-subtle);
  font-size: 0.78rem;
  text-transform: uppercase;
}

.post-title {
  font-size: clamp(1.6rem, 3vw, 2.3rem);
  font-weight: 800;
  margin: 0;
  line-height: 1.25;
}

.page-content,
.post-content,
.about-content {
  font-size: 1.02rem;
}

.about-content {
  max-width: 760px;
}

.about-content p {
  color: var(--color-text);
}

.about-lede {
  font-size: 1.25rem;
  font-weight: 600;
  line-height: 1.4;
  color: var(--color-text);
}

.about-subhead {
  margin: 1.8em 0 0.5em;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--color-accent);
}

.about-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
  gap: 18px;
  margin-top: 28px;
}

.about-card {
  padding: 22px;
  border: 1.5px solid var(--color-accent);
  border-radius: var(--radius);
  background: var(--color-card-bg);
}

.about-card-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 42px;
  height: 42px;
  margin-bottom: 14px;
  border-radius: 10px;
  background: var(--color-bg-subtle);
  color: var(--color-accent);
}

.about-card-title {
  margin: 0 0 8px;
  font-size: 1rem;
  font-weight: 700;
  color: var(--color-text);
}

.about-card-body {
  margin: 0;
  font-size: 0.92rem;
  color: var(--color-text-muted) !important;
  line-height: 1.55;
}

.about-signature {
  display: flex;
  gap: 18px;
  align-items: flex-start;
  margin-top: 36px;
  padding: 24px;
  background: var(--color-bg-subtle);
  border-radius: var(--radius);
}

.about-signature-avatar {
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 52px;
  height: 52px;
  border-radius: 50%;
  background: var(--color-navy);
  color: #fff;
  font-weight: 700;
  font-size: 1.1rem;
  letter-spacing: 0.02em;
}

.about-signature-text {
  min-width: 0;
}

.about-signature-name {
  margin: 0 0 2px;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--color-text);
}

.about-signature-role {
  margin: 0 0 10px;
  font-size: 0.85rem;
  color: var(--color-accent);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.about-signature-body {
  margin: 0;
  font-size: 0.92rem;
  color: var(--color-text-muted) !important;
  line-height: 1.55;
}

.page-content h2,
.post-content h2 {
  margin-top: 2em;
  font-size: 1.4rem;
}

.page-content h3,
.post-content h3 {
  margin-top: 1.6em;
  font-size: 1.15rem;
}

.page-content p,
.post-content p {
  color: var(--color-text);
}

.page-content img,
.post-content img {
  max-width: 100%;
  border-radius: 10px;
  border: 1px solid var(--color-border);
}

.page-content code,
.post-content code {
  font-family: var(--font-mono);
  background: var(--color-bg-subtle);
  padding: 2px 6px;
  border-radius: 6px;
  font-size: 0.9em;
}

.page-content pre,
.post-content pre {
  background: #1b1b1b;
  color: #eee;
  padding: 16px;
  border-radius: 10px;
  overflow-x: auto;
}

.page-content pre code,
.post-content pre code {
  background: none;
  padding: 0;
  color: inherit;
}

.page-content ul,
.post-content ul {
  padding-left: 1.3em;
}

/* Post nav */
.post-nav {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding-bottom: 56px;
  border-top: 1px solid var(--color-border);
  padding-top: 24px;
}

.post-nav-link {
  display: flex;
  flex-direction: column;
  gap: 4px;
  max-width: 45%;
  color: var(--color-text);
}

.post-nav-next {
  margin-left: auto;
  text-align: right;
}

.post-nav-label {
  font-size: 0.8rem;
  color: var(--color-text-muted);
}

.post-nav-title {
  font-weight: 600;
}

.ext-page-category {
  margin: 0 0 6px;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--color-text-muted);
}

.ext-page-github {
  display: inline-block;
  font-weight: 600;
}

.contact-form {
  display: grid;
  gap: 18px;
  max-width: 560px;
  margin: 24px 0;
}

.contact-form label {
  display: block;
  font-weight: 600;
  font-size: 0.95rem;
}

.contact-form input,
.contact-form textarea {
  display: block;
  margin-top: 6px;
}

.contact-optional {
  font-weight: 400;
  color: var(--color-text-muted);
}

.contact-form input,
.contact-form textarea {
  width: 100%;
  padding: 11px 13px;
  font: inherit;
  font-weight: 400;
  color: var(--color-text);
  background: var(--color-card-bg);
  border: 1px solid var(--color-border);
  border-radius: 10px;
}

.contact-form input:focus,
.contact-form textarea:focus {
  outline: 2px solid var(--color-accent);
  outline-offset: 1px;
  border-color: transparent;
}

.contact-form textarea {
  resize: vertical;
}

.contact-submit {
  justify-self: start;
  padding: 12px 22px;
  font: inherit;
  font-weight: 700;
  color: var(--color-accent-contrast);
  background: var(--color-accent);
  border: 0;
  border-radius: 999px;
  cursor: pointer;
}

.contact-note {
  margin: 0;
  font-size: 0.85rem;
  color: var(--color-text-muted);
}

.contact-direct {
  color: var(--color-text-muted);
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--color-border);
  padding: 28px 0;
  margin-top: 24px;
}

.site-footer-inner {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  color: var(--color-text-muted);
  font-size: 0.9rem;
}

.site-footer-links {
  display: flex;
  gap: 16px;
}

/* Responsive */
@media (max-width: 600px) {
  .site-header-inner {
    position: relative;
    flex-wrap: wrap;
  }

  .site-header-right {
    flex-wrap: wrap;
    justify-content: flex-end;
    width: 100%;
  }

  .nav-toggle {
    display: block;
  }

  .site-nav {
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    left: 0;
    z-index: 20;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    margin: 0 16px;
    padding: 8px;
    background: var(--color-card-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    box-shadow: 0 16px 32px rgba(0, 0, 0, 0.16);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-6px);
    transition: opacity 0.15s ease, transform 0.15s ease, visibility 0.15s;
  }

  .nav-trigger:checked ~ .site-nav {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }

  .site-nav a {
    width: 100%;
    padding: 12px 10px;
    border-radius: 8px;
  }

  .site-nav a:hover {
    background: var(--color-bg-subtle);
  }

  .hero {
    padding: 48px 0 32px;
  }

  .card-grid {
    gap: 28px;
  }

  .post-nav {
    flex-direction: column;
  }

  .post-nav-link {
    max-width: 100%;
  }

  .post-nav-next {
    text-align: left;
  }
}