:root {
  --ink: #16171a;
  --muted: #5b5f66;
  --rule: #e2e3e6;
  --accent: #d6381c;   /* 4.65:1 on paper */
  --paper: #fdfdfc;
  --measure: 36rem;
  --sans: "Helvetica Neue", Helvetica, Arial, "Liberation Sans", sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --ink: #e9eaec;
    --muted: #a0a4ac;
    --rule: #2c2e33;
    --accent: #ff7a5c; /* 7.18:1 on dark paper */
    --paper: #131417;
  }
}

/* Explicit choice wins over the system preference, in both directions. */
:root[data-theme="dark"] {
  --ink: #e9eaec;
  --muted: #a0a4ac;
  --rule: #2c2e33;
  --accent: #ff7a5c; /* 7.18:1 on dark paper */
  --paper: #131417;
}

:root[data-theme="light"] {
  --ink: #16171a;
  --muted: #5b5f66;
  --rule: #e2e3e6;
  --accent: #d6381c;   /* 4.65:1 on paper */
  --paper: #fdfdfc;
}

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

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  padding: 0 1.5rem 4rem;
  background: var(--paper);
  color: var(--ink);
  /* Helvetica set tight — Swiss convention, and Ville is a graphic designer.
     Arial is metric-compatible, so the tracking holds where Helvetica is absent. */
  font-family: var(--sans);
  font-size: 1.0625rem;
  line-height: 1.55;
  font-synthesis-weight: none;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.skip {
  position: absolute;
  left: -9999px;
}
.skip:focus {
  left: 1rem;
  top: 1rem;
  background: var(--accent);
  color: #fff;
  padding: 0.5rem 0.75rem;
  border-radius: 3px;
}

.site-head,
main,
.site-foot { max-width: var(--measure); margin-inline: auto; }

.site-head {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.25rem;
  align-items: baseline;
  padding: 2.5rem 0 2rem;
  border-bottom: 1px solid var(--rule);
}

.wordmark {
  font-weight: 700;
  letter-spacing: -0.03em;
  text-decoration: none;
  color: var(--ink);
  margin-right: auto;
}

.site-head nav {
  display: flex;
  flex-wrap: wrap;
  gap: 1.125rem;
  font-size: 0.8125rem;
  letter-spacing: -0.018em;
}

.site-head nav a { color: var(--muted); text-decoration: none; }
.site-head nav a:hover { color: var(--ink); }
.site-head nav a[aria-current="page"] { color: var(--ink); text-decoration: underline; text-underline-offset: 4px; }
.site-head nav a.lang { color: var(--accent); }

main { padding-top: 2.5rem; }

h1 {
  font-size: 2.125rem;
  line-height: 1.08;
  letter-spacing: -0.037em;
  margin: 0 0 0.875rem;
  font-weight: 700;
}

.lede {
  color: var(--muted);
  font-size: 1.1875rem;
  line-height: 1.45;
  margin: 0 0 2.25rem;
  max-width: 30rem;
}

h2 {
  font-size: 1.0625rem;
  font-weight: 700;
  letter-spacing: -0.021em;
  margin: 2.75rem 0 0.6rem;
}

p { margin: 0 0 1.25rem; }

a {
  color: var(--accent);
  text-underline-offset: 3px;
  text-decoration-thickness: 1px;
  text-decoration-color: color-mix(in srgb, var(--accent) 45%, transparent);
}
a:hover { text-decoration-thickness: 2px; text-decoration-color: var(--accent); }
a:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 2px; }

strong { font-weight: 600; }

ul.projects { list-style: none; margin: 0 0 2rem; padding: 0; }
ul.projects li { padding: 1.25rem 0; border-bottom: 1px solid var(--rule); }
ul.projects li:first-child { border-top: 1px solid var(--rule); }
ul.projects a {
  font-weight: 700;
  font-size: 1.0625rem;
  letter-spacing: -0.022em;
  text-decoration: none;
}
ul.projects a:hover { text-decoration: underline; }
ul.projects p { margin: 0.35rem 0 0; color: var(--muted); font-size: 0.9375rem; }

.sources {
  margin-top: 3.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--rule);
  font-size: 0.875rem;
  color: var(--muted);
}
.sources h2 { font-size: 0.6875rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.08em; margin: 0 0 0.75rem; }
.sources ol { margin: 0; padding-left: 1.25rem; }
.sources li { margin-bottom: 0.5rem; }

.site-foot {
  margin-top: 4rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--rule);
  font-size: 0.75rem;
  letter-spacing: 0;
  color: var(--muted);
}
.site-foot p { margin: 0; }

/* Theme switcher */
.theme-toggle {
  appearance: none;
  border: 1px solid var(--rule);
  background: transparent;
  color: var(--muted);
  border-radius: 999px;
  width: 3.25rem;
  height: 1.625rem;
  padding: 0;
  position: relative;
  cursor: pointer;
  flex: none;
  transition: border-color 0.2s, background-color 0.2s;
}
.theme-toggle:hover { border-color: var(--accent); }
.theme-toggle:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }

.theme-toggle .knob {
  position: absolute;
  top: 50%;
  left: 0.1875rem;
  width: 1.125rem;
  height: 1.125rem;
  margin-top: -0.5625rem;
  border-radius: 50%;
  background: var(--accent);
  transition: transform 0.24s cubic-bezier(0.4, 0, 0.2, 1);
}
:root[data-theme="dark"] .theme-toggle .knob { transform: translateX(1.5rem); }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .theme-toggle .knob { transform: translateX(1.5rem); }
}

.theme-toggle .glyph {
  position: absolute;
  top: 50%;
  margin-top: -0.4375rem;
  width: 0.875rem;
  height: 0.875rem;
  color: var(--muted);
  transition: opacity 0.2s;
}
.theme-toggle .glyph.sun { left: 0.375rem; }
.theme-toggle .glyph.moon { right: 0.375rem; }
:root[data-theme="dark"] .theme-toggle .glyph.moon { opacity: 0; }
:root[data-theme="light"] .theme-toggle .glyph.sun { opacity: 0; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .theme-toggle .glyph.moon { opacity: 0; }
}
@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) .theme-toggle .glyph.sun { opacity: 0; }
}

@media (prefers-reduced-motion: reduce) {
  .theme-toggle .knob { transition: none; }
}