@import url("https://fonts.googleapis.com/css2?family=IBM+Plex+Serif:wght@400;500;600&family=JetBrains+Mono:wght@400;600&family=Noto+Sans+SC:wght@400;500;600&family=Noto+Serif+SC:wght@400;500;600&family=Space+Grotesk:wght@400;500;600;700&display=swap");

:root {
  color-scheme: light;
  --paper: #f5f1ea;
  --paper-strong: #fffdf8;
  --ink: #1a1a1a;
  --muted: #5f5f5f;
  --accent: #df5e36;
  --accent-2: #2f8f7a;
  --border: rgba(23, 23, 23, 0.1);
  --shadow: 0 20px 50px rgba(20, 20, 20, 0.1);
  --radius-lg: 24px;
  --radius-md: 16px;
  --radius-sm: 10px;
  --font-body: "IBM Plex Serif", "Noto Serif SC", serif;
  --font-display: "Space Grotesk", "Noto Sans SC", sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, monospace;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: var(--font-body);
  color: var(--ink);
  background: var(--paper);
  min-height: 100vh;
  line-height: 1.7;
  letter-spacing: 0.01em;
}

html {
  scroll-behavior: smooth;
}

.bg-grid {
  position: fixed;
  inset: 0;
  z-index: -1;
  background-image:
    radial-gradient(circle at 15% 20%, rgba(223, 94, 54, 0.08), transparent 55%),
    radial-gradient(circle at 85% 15%, rgba(47, 143, 122, 0.12), transparent 50%),
    linear-gradient(120deg, rgba(255, 255, 255, 0.7), rgba(255, 255, 255, 0));
  background-size: 120% 120%;
  animation: paper-drift 18s ease-in-out infinite;
  pointer-events: none;
}

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

img {
  max-width: 100%;
  border-radius: var(--radius-sm);
}

.page {
  width: min(1100px, 92vw);
  margin: 0 auto;
  padding: 130px 0 90px;
}

.site-header {
  position: relative;
}

.nav {
  position: fixed;
  top: 24px;
  left: 24px;
  z-index: 40;
}

.nav-panel {
  display: grid;
  gap: 8px;
  width: 56px;
  max-height: 56px;
  padding: 6px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.86);
  border: 1px solid var(--border);
  box-shadow: 0 12px 30px rgba(15, 23, 42, 0.12);
  backdrop-filter: blur(14px);
  align-items: center;
  justify-items: center;
  grid-auto-rows: min-content;
  transition:
    width 260ms cubic-bezier(0.2, 0.8, 0.2, 1),
    max-height 260ms cubic-bezier(0.2, 0.8, 0.2, 1),
    padding 260ms ease,
    border-radius 260ms ease,
    box-shadow 260ms ease;
  overflow: hidden;
}

.nav:hover .nav-panel,
.nav.is-open .nav-panel,
.nav:focus-within .nav-panel {
  width: 220px;
  max-height: 420px;
  padding: 10px;
  border-radius: 20px;
  box-shadow: 0 20px 40px rgba(15, 23, 42, 0.2);
  align-items: stretch;
  justify-items: stretch;
}

.nav-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  padding: 0;
  border: none;
  border-radius: 50%;
  background: #fff;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--ink);
  cursor: pointer;
  box-shadow: inset 0 0 0 1px rgba(0, 0, 0, 0.08);
  transition: transform 200ms ease, box-shadow 200ms ease;
}

.nav-toggle:hover {
  transform: translateY(-1px);
  box-shadow: 0 10px 24px rgba(15, 23, 42, 0.18);
}

.nav-toggle-icon {
  position: relative;
  width: 18px;
  height: 2px;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
}

.nav-toggle-icon::before,
.nav-toggle-icon::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  height: 2px;
  border-radius: inherit;
  background: inherit;
}

.nav-toggle-icon::before {
  top: -5px;
}

.nav-toggle-icon::after {
  top: 5px;
}

.nav-toggle:focus-visible {
  outline: 2px solid rgba(223, 94, 54, 0.6);
  outline-offset: 3px;
}

.nav-link {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 12px;
  border-radius: 12px;
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 0.95rem;
  color: var(--muted);
  opacity: 0;
  transform: translateX(-8px);
  transition:
    opacity 220ms ease,
    transform 220ms ease,
    background 220ms ease,
    color 220ms ease;
  pointer-events: none;
}

.nav:hover .nav-link,
.nav.is-open .nav-link,
.nav:focus-within .nav-link {
  opacity: 1;
  transform: translateX(0);
  pointer-events: auto;
  transition-delay: calc(var(--i) * 40ms);
}

.nav-link:hover {
  background: rgba(223, 94, 54, 0.12);
  color: var(--ink);
}

.nav-link.active {
  background: var(--accent);
  color: #fff;
}

.hero {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 32px;
  align-items: center;
}

.eyebrow {
  font-family: var(--font-display);
  text-transform: uppercase;
  letter-spacing: 0.2em;
  font-size: 0.75rem;
  color: var(--muted);
}

.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(2.4rem, 4vw, 3.6rem);
  margin: 10px 0 12px;
}

.lead {
  font-size: 1.1rem;
  color: var(--muted);
  margin: 0 0 18px;
}

.hero-actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 18px;
  border-radius: 999px;
  background: var(--accent);
  color: #fff;
  font-family: var(--font-display);
  font-weight: 600;
  box-shadow: 0 12px 24px rgba(223, 94, 54, 0.2);
  transition: transform 220ms ease, box-shadow 220ms ease, background 220ms ease;
}

.button.ghost {
  background: transparent;
  color: var(--ink);
  border: 1px solid var(--border);
  box-shadow: none;
}

.button:hover {
  transform: translateY(-2px);
  box-shadow: 0 16px 30px rgba(223, 94, 54, 0.28);
}

.hero-card {
  background: var(--paper-strong);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px;
  box-shadow: var(--shadow);
}

.card-title {
  font-family: var(--font-display);
  font-weight: 600;
  margin-bottom: 12px;
}

.section-title {
  font-family: var(--font-display);
  font-size: 1.1rem;
  margin: 48px 0 18px;
}

.post-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 18px;
}

.post-card,
.post-item,
.search-card {
  background: var(--paper-strong);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 18px;
  transition: transform 220ms ease, box-shadow 220ms ease;
}

.post-card:hover,
.post-item:hover,
.search-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 18px 30px rgba(20, 20, 20, 0.12);
}

.post-card-header,
.post-item {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 12px;
}

.post-item {
  align-items: center;
}

.post-item h2,
.post-card h3 {
  margin: 0 0 10px;
  font-family: var(--font-display);
}

.post-date {
  font-family: var(--font-display);
  font-size: 0.85rem;
  color: var(--muted);
}

.post-summary {
  margin: 0 0 12px;
  color: var(--muted);
}

.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.tag {
  padding: 4px 10px;
  border-radius: 999px;
  background: rgba(47, 143, 122, 0.14);
  color: var(--accent-2);
  font-size: 0.8rem;
  font-family: var(--font-display);
  transition: transform 200ms ease, background 200ms ease, color 200ms ease;
}

.tag:hover {
  transform: translateY(-1px);
  background: rgba(47, 143, 122, 0.2);
  color: #1b5f52;
}

.page-header h1 {
  font-family: var(--font-display);
  margin-bottom: 6px;
}

.page-header p {
  margin-top: 0;
  color: var(--muted);
}

.post-list {
  display: grid;
  gap: 16px;
}

.post-layout {
  display: grid;
  grid-template-columns: 200px minmax(0, 1fr);
  gap: 22px;
}

.toc {
  position: sticky;
  top: 110px;
  align-self: start;
  background: var(--paper-strong);
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  padding: 16px;
  margin-left: -18px;
  max-height: 70vh;
  overflow: auto;
}

.toc-title {
  font-family: var(--font-display);
  font-weight: 600;
  margin-bottom: 12px;
}

.toc-links {
  display: grid;
  gap: 8px;
}

.toc-link {
  font-size: 0.9rem;
  color: var(--muted);
}

.toc-link.level-3 {
  padding-left: 12px;
}

.toc-link.level-4 {
  padding-left: 22px;
}

.toc-link:hover {
  color: var(--accent);
}

.toc-empty {
  color: var(--muted);
  font-size: 0.9rem;
}

.markdown {
  font-size: 1.02rem;
}

.markdown h1,
.markdown h2,
.markdown h3,
.markdown h4 {
  font-family: var(--font-display);
  margin-top: 2.2rem;
  scroll-margin-top: 110px;
}

.markdown h2 {
  font-size: 1.6rem;
}

.markdown h3 {
  font-size: 1.3rem;
}

.markdown p {
  margin: 1rem 0;
}

.markdown a {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 4px;
}

.markdown blockquote {
  margin: 1.6rem 0;
  padding: 1rem 1.2rem;
  background: rgba(223, 94, 54, 0.08);
  border-left: 3px solid var(--accent);
  border-radius: var(--radius-sm);
}

.markdown pre {
  background: #1f1f1f;
  color: #f4f4f4;
  padding: 16px;
  border-radius: var(--radius-sm);
  overflow: auto;
}

.markdown code {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  background: rgba(31, 31, 31, 0.08);
  padding: 0.1rem 0.3rem;
  border-radius: 6px;
}

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

.markdown ul,
.markdown ol {
  padding-left: 1.2rem;
}

.markdown table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.6rem 0;
}

.markdown th,
.markdown td {
  border: 1px solid var(--border);
  padding: 0.6rem;
  text-align: left;
}

.search-panel {
  display: grid;
  gap: 16px;
}

.search-bar {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.search-input {
  flex: 1 1 260px;
  padding: 12px 14px;
  border-radius: 12px;
  border: 1px solid var(--border);
  font-family: var(--font-display);
  font-size: 0.95rem;
}

.search-clear {
  padding: 10px 16px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--paper-strong);
  font-family: var(--font-display);
  cursor: pointer;
}

.search-stats {
  color: var(--muted);
  font-size: 0.9rem;
}

.site-footer {
  text-align: center;
  padding: 40px 0 60px;
  color: var(--muted);
  font-size: 0.9rem;
}

.empty-state {
  padding: 20px;
  background: rgba(255, 255, 255, 0.7);
  border-radius: var(--radius-md);
  border: 1px dashed var(--border);
  color: var(--muted);
}

[data-reveal] {
  opacity: 0;
  transform: translateY(16px);
  transition:
    opacity 650ms ease,
    transform 650ms cubic-bezier(0.22, 0.8, 0.28, 1);
  transition-delay: var(--delay, 0ms);
  will-change: transform, opacity;
}

[data-reveal].is-visible {
  opacity: 1;
  transform: translateY(0);
}

@media (max-width: 900px) {
  .hero {
    grid-template-columns: 1fr;
  }

  .post-layout {
    grid-template-columns: 1fr;
  }

  .toc {
    position: relative;
    top: auto;
    margin-left: 0;
  }
}

@media (min-width: 1024px) {
  .page-post .page {
    --toc-width: 220px;
    --toc-gap: 24px;
    width: min(
      1100px,
      calc(
        100% - (var(--toc-width) + var(--toc-gap)) - (var(--toc-width) + var(--toc-gap))
      )
    );
    margin: 0 auto;
  }

  .page-post .post-layout {
    display: block;
  }

  .page-post .toc {
    position: fixed;
    left: 24px;
    top: 96px;
    transform: none;
    margin-left: 0;
    width: var(--toc-width);
    max-height: calc(100vh - 120px);
    z-index: 20;
  }
}

@media (max-width: 720px) {
  .page {
    padding-top: 110px;
  }

  .nav {
    top: 18px;
    left: 18px;
  }

  .nav:hover .nav-panel {
    width: min(240px, 84vw);
  }
}

@media (prefers-reduced-motion: reduce) {
  * {
    scroll-behavior: auto;
    transition: none !important;
  }

  .bg-grid {
    animation: none !important;
  }
}

@keyframes paper-drift {
  0% {
    background-position: 0% 0%;
  }
  50% {
    background-position: 70% 35%;
  }
  100% {
    background-position: 0% 0%;
  }
}