:root {
  --sans:
    -apple-system,
    BlinkMacSystemFont,
    "SF Pro Display",
    "SF Pro Text",
    "Segoe UI",
    Helvetica,
    Arial,
    sans-serif;
  --mono: "SFMono-Regular", ui-monospace, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
}

:root[data-theme="dark"] {
  --bg: #000000;
  --panel-soft: #111111;
  --ink: #f5f5f7;
  --muted: rgba(245, 245, 247, 0.72);
  --soft: rgba(245, 245, 247, 0.52);
  --line: rgba(245, 245, 247, 0.12);
  --line-strong: rgba(245, 245, 247, 0.24);
  --surface-hover: rgba(255, 255, 255, 0.08);
  --surface-active: rgba(255, 255, 255, 0.12);
  --code-inline: rgba(255, 255, 255, 0.08);
}

:root[data-theme="light"] {
  --bg: #f7f7f5;
  --panel-soft: #f0efea;
  --ink: #111111;
  --muted: rgba(17, 17, 17, 0.68);
  --soft: rgba(17, 17, 17, 0.48);
  --line: rgba(17, 17, 17, 0.1);
  --line-strong: rgba(17, 17, 17, 0.18);
  --surface-hover: rgba(17, 17, 17, 0.05);
  --surface-active: rgba(17, 17, 17, 0.08);
  --code-inline: rgba(17, 17, 17, 0.06);
}

* {
  box-sizing: border-box;
}

html {
  min-height: 100%;
  background: var(--bg);
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  transition: background 180ms ease, color 180ms ease;
}

body.mobile-menu-open {
  overflow: hidden;
}

button,
input,
textarea,
select {
  font: inherit;
}

a {
  color: inherit;
  text-decoration: none;
}

.site-frame {
  min-height: 100vh;
}

.site-footer {
  border-top: 1px solid var(--line);
}

.site-footer-row {
  width: min(1760px, calc(100vw - 64px));
  margin: 0 auto;
  padding: 22px 0 28px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.footer-links,
.footer-meta {
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

.footer-link {
  color: var(--muted);
  transition: color 160ms ease;
}

.footer-link:hover,
.footer-link:focus-visible {
  color: var(--ink);
  outline: none;
}

.footer-link-button {
  border: 0;
  background: transparent;
  padding: 0;
  cursor: pointer;
}

.footer-link.is-disabled {
  opacity: 0.45;
  pointer-events: none;
}

.footer-note {
  margin: 0;
  color: var(--soft);
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(18px);
  border-bottom: 1px solid transparent;
}

.site-header-row {
  width: min(1760px, calc(100vw - 64px));
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 18px 0;
}

.brand-mark {
  display: inline-flex;
  align-items: center;
  gap: 18px;
  min-width: 0;
}

.brand-logo {
  width: 48px;
  height: auto;
  display: block;
  flex: 0 0 auto;
}

.brand-logo-light {
  display: none;
}

:root[data-theme="dark"] .brand-logo-light {
  display: block;
}

:root[data-theme="dark"] .brand-logo-dark {
  display: none;
}

.brand-name {
  font-size: 1.35rem;
  line-height: 1;
  font-weight: 600;
  letter-spacing: -0.03em;
  white-space: nowrap;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.mobile-header-actions {
  display: none;
  align-items: center;
  gap: 10px;
}

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

.category-pill,
.theme-toggle,
.menu-toggle,
.share-button {
  border: 0;
  border-radius: 999px;
  background: transparent;
  color: var(--muted);
  padding: 10px 16px;
  cursor: pointer;
  transition: color 160ms ease, background 160ms ease, border-color 160ms ease;
}

.theme-toggle {
  width: 44px;
  height: 44px;
  padding: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.mobile-icon-button,
.menu-toggle {
  width: 44px;
  height: 44px;
  padding: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.menu-icon {
  width: 20px;
  height: 20px;
  display: block;
}

.menu-icon-close {
  display: none;
}

.menu-toggle.is-active .menu-icon-open {
  display: none;
}

.menu-toggle.is-active .menu-icon-close {
  display: block;
}

.theme-icon {
  width: 18px;
  height: 18px;
  display: block;
}

.theme-icon-moon {
  display: none;
}

:root[data-theme="light"] .theme-icon-sun {
  display: none;
}

:root[data-theme="light"] .theme-icon-moon {
  display: block;
}

.category-pill:hover,
.category-pill:focus-visible,
.theme-toggle:hover,
.theme-toggle:focus-visible,
.menu-toggle:hover,
.menu-toggle:focus-visible,
.share-button:hover,
.share-button:focus-visible {
  background: var(--surface-hover);
  color: var(--ink);
  outline: none;
}

.category-pill.is-active,
.theme-toggle.is-active,
.menu-toggle.is-active {
  background: var(--surface-active);
  color: var(--ink);
}

.page-shell {
  width: min(1760px, calc(100vw - 64px));
  margin: 0 auto;
}

.mobile-menu {
  position: fixed;
  top: 64px;
  right: 0;
  bottom: 0;
  left: 0;
  z-index: 30;
  background: color-mix(in srgb, var(--bg) 92%, transparent);
  backdrop-filter: blur(20px);
}

.mobile-menu-panel {
  min-height: calc(100vh - 64px);
  padding: 24px 24px 32px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.mobile-menu-nav {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 6px;
}

.mobile-menu-link,
.mobile-menu-secondary {
  border: 0;
  background: transparent;
  color: var(--ink);
  padding: 0;
  text-align: left;
  cursor: pointer;
}

.mobile-menu-link {
  font-size: clamp(2.8rem, 10vw, 4.3rem);
  line-height: 1.02;
  letter-spacing: -0.06em;
  font-weight: 500;
}

.mobile-menu-link.is-active {
  color: var(--muted);
}

.mobile-menu-footer {
  display: flex;
  flex-wrap: wrap;
  gap: 16px 22px;
  padding-top: 28px;
  border-top: 1px solid var(--line);
}

.mobile-menu-secondary {
  color: var(--muted);
  font-size: 1rem;
  line-height: 1.4;
}

.main-panel {
  display: flex;
  flex-direction: column;
  min-width: 0;
}

.article-index {
  max-width: 1280px;
  width: 100%;
  margin: 56px auto 0;
}

.index-header {
  margin-bottom: 22px;
}

.index-title {
  margin: 0;
  color: var(--ink);
  font-size: clamp(2.1rem, 4vw, 3.6rem);
  line-height: 0.98;
  font-weight: 500;
  letter-spacing: -0.045em;
}

.article-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
}

.article-link {
  border: 1px solid var(--line);
  border-radius: 22px;
  background: transparent;
  color: inherit;
  text-align: left;
  padding: 22px;
  min-height: 220px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  cursor: pointer;
  transition:
    background 180ms ease,
    border-color 180ms ease,
    transform 180ms ease,
    box-shadow 180ms ease;
}

.article-link:hover,
.article-link:focus-visible {
  background: var(--surface-hover);
  border-color: var(--line-strong);
  box-shadow: 0 22px 50px -28px rgba(0, 0, 0, 0.55);
  transform: translateY(-3px);
  outline: none;
}

.article-link.is-active {
  background: var(--surface-active);
  border-color: var(--line-strong);
}

.article-link:hover .article-link-title,
.article-link:focus-visible .article-link-title {
  color: color-mix(in srgb, var(--ink) 92%, white 8%);
}

.article-link:hover .article-link-excerpt,
.article-link:focus-visible .article-link-excerpt,
.article-link:hover .article-link-meta,
.article-link:focus-visible .article-link-meta {
  color: var(--ink);
}

.article-link-title {
  color: var(--ink);
  font-size: 1.35rem;
  line-height: 1.25;
  font-weight: 500;
}

.article-link-excerpt {
  color: var(--muted);
  font-size: 1rem;
  line-height: 1.55;
  flex: 1;
}

.article-link-meta {
  color: var(--muted);
  font-size: 0.95rem;
  line-height: 1.4;
}

.article-link-divider {
  opacity: 0.72;
  margin: 0 6px;
}

.hero-card {
  max-width: 900px;
  margin: 96px auto 0;
  padding: 140px 0 72px;
  text-align: center;
}

.hero-card.page-hero {
  margin-top: 40px;
  padding-top: 48px;
}

.hero-meta-line {
  margin: 0 0 34px;
  color: var(--muted);
  font-size: 1rem;
  line-height: 1.4;
}

.hero-date::after {
  content: "";
  display: inline-block;
  width: 1px;
  height: 1em;
  margin: 0 18px;
  vertical-align: -0.15em;
  background: var(--line-strong);
}

.hero-card h1 {
  margin: 0;
  max-width: 100%;
  font-size: clamp(2.7rem, 5.4vw, 5rem);
  line-height: 0.96;
  font-weight: 500;
  letter-spacing: -0.055em;
}

.hero-author {
  margin: 34px 0 0;
  color: var(--ink);
  font-size: 1rem;
  line-height: 1.5;
}

.hero-actions {
  margin-top: 34px;
  display: flex;
  justify-content: center;
  gap: 12px;
}

.share-button {
  border: 1px solid var(--line);
  color: var(--ink);
  padding: 10px 18px;
}

.share-button:hover,
.share-button:focus-visible {
  border-color: var(--line-strong);
}

.reader-card {
  max-width: 900px;
  width: 100%;
  min-width: 0;
  margin: 56px auto 0;
  padding: 0 0 120px;
}

.markdown-body {
  max-width: 900px;
  width: 100%;
  min-width: 0;
}

.markdown-body h1 {
  display: none;
}

.markdown-body h2,
.markdown-body h3 {
  color: var(--ink);
  font-weight: 500;
  letter-spacing: -0.03em;
}

.markdown-body h2 {
  margin: 72px 0 18px;
  font-size: clamp(2rem, 3vw, 2.7rem);
  line-height: 1.02;
}

.markdown-body h3 {
  margin: 40px 0 14px;
  font-size: 1.45rem;
  line-height: 1.14;
}

.markdown-body p,
.markdown-body ul,
.markdown-body ol,
.markdown-body pre,
.markdown-body blockquote,
.markdown-body img {
  margin: 0 0 28px;
}

.markdown-body p,
.markdown-body li,
.markdown-body blockquote {
  max-width: 860px;
  color: var(--ink);
  font-size: 1.18rem;
  line-height: 1.72;
  overflow-wrap: anywhere;
}

.markdown-body ul,
.markdown-body ol {
  max-width: 860px;
  padding-left: 26px;
}

.markdown-body li + li {
  margin-top: 10px;
}

.markdown-body code {
  font-family: var(--mono);
  font-size: 0.84em;
  padding: 0.14em 0.34em;
  border-radius: 6px;
  background: var(--code-inline);
  color: var(--ink);
}

.markdown-body pre {
  overflow-x: auto;
  padding: 20px 22px;
  border-radius: 16px;
  background: var(--panel-soft);
  border: 1px solid var(--line);
}

.markdown-body pre code {
  padding: 0;
  background: transparent;
}

.markdown-body blockquote {
  padding-left: 18px;
  border-left: 2px solid var(--line-strong);
  color: var(--muted);
}

.markdown-body a {
  color: var(--ink);
  text-decoration: underline;
  text-decoration-color: var(--line-strong);
  text-underline-offset: 0.16em;
}

.markdown-body img {
  display: block;
  max-width: 100%;
  height: auto;
  border-radius: 18px;
  border: 1px solid var(--line);
}

.empty-state {
  display: none;
}

@media (max-width: 980px) {
  .site-header-row,
  .page-shell,
  .site-footer-row {
    width: min(100vw - 24px, 1760px);
  }

  .site-header-row {
    gap: 18px;
  }

  .brand-name {
    font-size: 1.15rem;
  }

  .header-actions {
    gap: 8px;
  }

  .hero-card {
    margin-top: 48px;
    padding-top: 72px;
    padding-bottom: 48px;
  }

  .article-list {
    grid-template-columns: 1fr;
  }

  .hero-card h1 {
    font-size: clamp(2.2rem, 9vw, 3.6rem);
  }

  .reader-card {
    padding-bottom: 80px;
  }

  .markdown-body p,
  .markdown-body li,
  .markdown-body blockquote {
    font-size: 1.04rem;
    line-height: 1.68;
  }
}

@media (max-width: 720px) {
  .site-header-row,
  .page-shell,
  .site-footer-row {
    width: calc(100vw - 24px);
    max-width: calc(100vw - 24px);
  }

  .site-header-row {
    align-items: center;
    justify-content: space-between;
    flex-direction: row;
    gap: 12px;
    padding: 10px 0;
  }

  .brand-mark {
    gap: 12px;
  }

  .brand-logo {
    width: 40px;
  }

  .brand-name {
    font-size: 1.1rem;
    letter-spacing: -0.04em;
  }

  .header-actions {
    display: none;
  }

  .mobile-header-actions {
    display: flex;
  }

  .article-index {
    margin-top: 18px;
  }

  .index-header {
    margin-bottom: 12px;
  }

  .article-link {
    min-height: 0;
    padding: 18px;
    border-radius: 18px;
  }

  .hero-card,
  .hero-card.page-hero {
    margin-top: 8px;
    padding: 32px 0 56px 0;
    text-align: center;
  }

  .hero-meta-line {
    margin-bottom: 12px;
    font-size: 0.95rem;
  }

  .hero-date::after {
    margin: 0 12px;
  }

  .hero-card h1 {
    font-size: clamp(2.35rem, 11vw, 3.2rem);
    line-height: 0.94;
    letter-spacing: -0.05em;
  }

  .hero-author {
    margin-top: 16px;
  }

  .hero-actions {
    margin-top: 16px;
    justify-content: center;
    flex-wrap: wrap;
    gap: 10px;
  }

  .share-button {
    padding: 10px 16px;
  }

  .reader-card {
    margin-top: 8px;
    padding: 0 12px 64px 12px;
  }

  .reader-card,
  .markdown-body,
  .markdown-body p,
  .markdown-body ul,
  .markdown-body ol,
  .markdown-body blockquote,
  .markdown-body pre {
    max-width: 100%;
  }

  .markdown-body h2 {
    margin: 52px 0 14px;
    font-size: clamp(1.8rem, 7vw, 2.3rem);
  }

  .markdown-body h3 {
    margin: 30px 0 12px;
    font-size: 1.3rem;
  }

  .markdown-body p,
  .markdown-body li,
  .markdown-body blockquote {
    font-size: 1rem;
    line-height: 1.7;
  }

  .markdown-body ul,
  .markdown-body ol {
    padding-left: 22px;
  }

  .markdown-body pre {
    margin-left: -2px;
    margin-right: -2px;
    padding: 16px 18px;
    border-radius: 14px;
  }

  .site-footer-row {
    align-items: flex-start;
    flex-direction: column;
    padding: 18px 0 24px;
  }
}