@font-face {
  font-family: 'Geist';
  src: url('/fonts/Geist-Regular.woff2') format('woff2');
  font-weight: 400;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: 'Geist';
  src: url('/fonts/Geist-Medium.woff2') format('woff2');
  font-weight: 500;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: 'Geist';
  src: url('/fonts/Geist-SemiBold.woff2') format('woff2');
  font-weight: 600;
  font-style: normal;
  font-display: swap;
}

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

:root {
  --bg: #fafafa;
  --text: #000;
  --text-secondary: rgba(0, 0, 0, 0.5);
  --text-tertiary: rgba(0, 0, 0, 0.3);
  --border: rgba(0, 0, 0, 0.1);
  --subtle: rgba(0, 0, 0, 0.04);
  --font: 'Geist', -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'SF Pro Text', system-ui, sans-serif;
  --spring: cubic-bezier(0.34, 1.56, 0.64, 1);
}

html[data-theme="dark"] {
  --bg: #111;
  --text: #e8e8e8;
  --text-secondary: rgba(255, 255, 255, 0.5);
  --text-tertiary: rgba(255, 255, 255, 0.25);
  --border: rgba(255, 255, 255, 0.1);
  --subtle: rgba(255, 255, 255, 0.04);
}

html.transition,
html.transition *,
html.transition *::before,
html.transition *::after {
  transition: background-color 0.4s ease, color 0.4s ease, border-color 0.4s ease !important;
}

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  font-weight: 400;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100dvh;
  -webkit-font-smoothing: antialiased;
  -webkit-tap-highlight-color: transparent;
}

.page-content { padding: 0; }

.w {
  max-width: 680px;
  margin: 0 auto;
  padding: clamp(4rem, 10vw, 8rem) clamp(1.25rem, 5vw, 3rem) 3rem;
  padding-left: max(clamp(1.25rem, 5vw, 3rem), env(safe-area-inset-left));
  padding-right: max(clamp(1.25rem, 5vw, 3rem), env(safe-area-inset-right));
  padding-bottom: max(3rem, env(safe-area-inset-bottom));
}

header { margin-bottom: clamp(4rem, 8vw, 6rem); }

header h1 {
  font-family: var(--font);
  font-size: clamp(3rem, 8vw, 6rem);
  font-weight: 200;
  letter-spacing: -0.03em;
  line-height: 1.1;
  margin: 1.5rem 0 0.5rem;
  color: var(--text);
}

header p {
  color: var(--text-secondary);
  font-size: 1rem;
  margin-bottom: 0;
}

h1, h2, h3, h4 {
  font-family: var(--font);
  font-weight: 500;
  color: var(--text);
  line-height: 1.25;
  letter-spacing: -0.01em;
  margin: 2.5rem 0 0.75rem;
}

h1 { font-size: clamp(2rem, 5vw, 2.75rem); font-weight: 300; letter-spacing: -0.02em; }
h2 { font-size: 1.35rem; font-weight: 500; }
h3 { font-size: 1.05rem; font-weight: 500; color: var(--text-secondary); }
h4 { font-size: 0.95rem; font-weight: 500; color: var(--text-secondary); }

p { margin: 0 0 1rem; color: var(--text); }

a {
  color: var(--text);
  text-decoration: none;
  border-bottom: 1px solid var(--border);
  transition: border-color 0.3s ease, color 0.3s ease;
}

a:hover { border-bottom-color: var(--text); }

ul, ol {
  margin: 0 0 1rem;
  padding-left: 1.25rem;
  color: var(--text);
}

ul li, ol li { margin: 0.25rem 0; }

.horizontal-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.horizontal-list li { margin: 0; }

.horizontal-list a {
  color: var(--text-secondary);
  border-bottom: none;
  transition: color 0.3s ease;
}

.horizontal-list a:hover { color: var(--text); }

.dashed {
  border-top: 1px dashed var(--border);
  margin: 1.5rem 0;
}

.glass-card {
  background: transparent;
  border: none;
  border-radius: 0;
  padding: 0;
  margin: 1rem 0 2rem;
}

.glass-card h2:first-child,
.glass-card h1:first-child,
.glass-card h3:first-child { margin-top: 0; }

.post-title {
  font-size: clamp(2.25rem, 6vw, 3.25rem);
  font-weight: 300;
  letter-spacing: -0.02em;
  line-height: 1.1;
  margin: 0 0 0.5rem;
}

.post-meta {
  color: var(--text-tertiary);
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  margin: 0 0 2.5rem;
}

article img,
.glass-card img,
.page-content img {
  max-width: 100%;
  height: auto;
  display: block;
  margin: 2rem auto;
  border: 1px solid var(--border);
  border-radius: 4px;
}

code {
  font-family: ui-monospace, SFMono-Regular, 'SF Mono', Menlo, monospace;
  font-size: 0.9em;
  background: var(--subtle);
  padding: 0.15em 0.4em;
  border-radius: 3px;
}

pre {
  background: var(--subtle);
  border-radius: 4px;
  padding: 1rem;
  overflow-x: auto;
  margin: 1rem 0;
}

pre code { background: none; padding: 0; }

blockquote {
  border-left: 2px solid var(--border);
  margin: 1rem 0;
  padding: 0 0 0 1rem;
  color: var(--text-secondary);
}

hr {
  border: none;
  border-top: 1px dashed var(--border);
  margin: 2.5rem 0;
}

footer {
  margin-top: clamp(4rem, 8vw, 6rem);
  padding-top: 1rem;
  color: var(--text-secondary);
  font-size: 0.9rem;
}

.theme-toggle {
  position: fixed;
  bottom: clamp(1rem, 3vw, 2rem);
  right: clamp(1rem, 3vw, 2rem);
  width: 36px;
  height: 36px;
  border-radius: 50%;
  border: 1px solid var(--border);
  background: var(--bg);
  color: var(--text-secondary);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0;
  transition: color 0.4s ease-out, border-color 0.4s ease-out, transform 0.2s var(--spring);
}

.theme-toggle:hover {
  color: var(--text);
  transform: translateY(-2px);
}

.theme-toggle svg { width: 16px; height: 16px; }

@media (max-width: 640px) {
  header { margin-bottom: 3rem; }
  .post-title { font-size: clamp(1.75rem, 7vw, 2.25rem); }
}