/* ── Tokens (aligned with thinkingmachines.ai/blog) ───────── */
:root {
  --content-pad: 1.3rem;
  --content-max: calc(660px + 2 * var(--content-pad));
  --site-header-height: 54px;

  --bg: #ffffff;
  --bg-code: #f3f3f2;
  --fg: #282828;
  --fg1: #3c3836;
  --fg2: #504945;
  --fg3: #6b6866;
  --fg4: #676767;
  --fg5: #969696;
  --red: #ad2111;

  --font-serif: "Source Serif 4", "Iowan Old Style", Georgia, serif;
  --font-sans: "DM Sans", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-hand: "Caveat", "Segoe Script", cursive;
  --font-mono: "IBM Plex Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

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

html {
  overflow-y: scroll;
  overflow-x: clip;
  scroll-padding-top: calc(var(--site-header-height) + 1rem);
  scrollbar-width: thin;
  scrollbar-color: var(--fg4) var(--bg);
}

body {
  font-family: var(--font-serif);
  font-size: 17px;
  line-height: 1.6;
  background: var(--bg);
  color: var(--fg);
  min-height: 100vh;
  overflow-x: clip;
  -webkit-font-smoothing: antialiased;
}

img,
svg {
  display: block;
  max-width: 100%;
  height: auto;
}

a {
  color: inherit;
}

::-webkit-scrollbar {
  width: 8px;
  height: 8px;
  background: var(--bg);
}

::-webkit-scrollbar-thumb {
  background: var(--fg4);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--fg1);
}

/* ── Shell ─────────────────────────────────────────────────── */
#wrapper {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  padding: var(--site-header-height) 1rem 0;
}

/* ── Header (Thinking Machines–style) ─────────────────────── */
#header {
  background: var(--bg);
}

#header .site-header {
  position: fixed;
  top: 0;
  left: 1rem;
  right: 1rem;
  z-index: 1002;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--site-header-height);
  padding: 0 1rem;
  background: var(--bg);
}

@media (min-width: 769px) {
  #header .site-header {
    padding-left: 0.33rem;
    padding-right: 0.33rem;
  }
}

.logo-handwritten {
  font-family: var(--font-hand) !important;
  font-size: 28px !important;
  font-weight: 500 !important;
  line-height: 1 !important;
  letter-spacing: 0.02em !important;
  color: var(--fg) !important;
  text-decoration: none !important;
  transition: opacity 0.2s ease;
}

.logo-handwritten:hover {
  opacity: 0.75;
}

.nav-group {
  display: flex;
  align-items: center;
}

.top-nav {
  display: flex;
  gap: 1.75rem;
  align-items: center;
  font-family: var(--font-sans);
}

.top-nav a {
  font-family: var(--font-sans) !important;
  font-size: 15px;
  font-weight: 400;
  letter-spacing: -0.01em;
  color: var(--fg1) !important;
  text-decoration: none;
}

.top-nav a:hover,
.top-nav a[aria-current="page"] {
  text-decoration: underline;
  text-decoration-color: color-mix(in srgb, var(--fg) 20%, transparent);
  text-underline-offset: 2px;
}

.hamburger {
  display: none;
  position: relative;
  width: 40px;
  height: 40px;
  margin-left: 0.5rem;
  padding: 8px;
  border: none;
  background: transparent;
  cursor: pointer;
}

.hamburger span {
  position: absolute;
  left: 9px;
  right: 9px;
  height: 2px;
  background: var(--fg3);
  border-radius: 2px;
  transition: transform 0.25s ease, opacity 0.2s ease, top 0.25s ease, bottom 0.25s ease;
}

.hamburger span:nth-child(1) { top: 12px; }
.hamburger span:nth-child(2) { top: 19px; }
.hamburger span:nth-child(3) { bottom: 12px; }

.hamburger.is-active span:nth-child(1) {
  top: 19px;
  transform: rotate(45deg);
}

.hamburger.is-active span:nth-child(2) {
  opacity: 0;
}

.hamburger.is-active span:nth-child(3) {
  top: 19px;
  bottom: auto;
  transform: rotate(-45deg);
}

.mobile-menu-overlay {
  position: fixed;
  inset: 0;
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity 0.25s ease, visibility 0.25s ease;
}

.mobile-menu-overlay[hidden] {
  display: none;
}

.mobile-menu-overlay.open {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

.mobile-menu-nav {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  text-align: center;
}

.mobile-menu-nav a {
  font-family: var(--font-sans);
  font-size: 20px;
  letter-spacing: -0.01em;
  color: var(--fg) !important;
  text-decoration: none;
}

body.menu-open {
  overflow: hidden;
}

/* ── Footer ────────────────────────────────────────────────── */
#footer {
  margin-top: auto;
  padding: 3.5rem 0 2.5rem;
  font-family: var(--font-sans);
  font-size: 13px;
  color: var(--fg4);
}

body:has(.comic-post) #footer {
  background: var(--album-bg, #f7f5f0);
}

body:has(.comic-post) #header .site-header {
  background: var(--album-bg, #f7f5f0);
}

.footer-inner {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 0 var(--content-pad);
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 1rem;
  border-top: 1px solid color-mix(in srgb, var(--fg4) 12%, transparent);
  padding-top: 1.5rem;
}

.footer-inner a {
  color: var(--fg3);
  text-decoration: none;
}

.footer-inner a:hover {
  color: var(--fg);
  text-decoration: underline;
  text-decoration-color: color-mix(in srgb, var(--fg) 20%, transparent);
  text-underline-offset: 2px;
}

@media (max-width: 768px) {
  :root {
    --site-header-height: 50px;
  }

  #wrapper {
    padding-left: 0.33rem;
    padding-right: 0.33rem;
  }

  #header .site-header {
    left: 0;
    right: 0;
    padding: 0.75rem 1rem;
  }
}

@media (max-width: 640px) {
  .top-nav {
    display: none;
  }

  .hamburger {
    display: inline-block;
  }

  #header .site-header {
    padding-right: 0.6rem;
  }

  .logo-handwritten {
    font-size: 26px !important;
  }
}