:root {
  color-scheme: light;
  --paper: #f6f7f4;
  --paper-raised: #ffffff;
  --ink: #1b222c;
  --ink-soft: #46505c;
  --neutral: #4e5966;
  --rule: #d6d9d2;
  --seal: #93312e;
  --seal-soft: #f3e4e2;
  --bronze: #6e5220;
  --bronze-soft: #f0e9da;
  --code-bg: #202834;
  --code-ink: #dde3ea;
  --code-comment: #d7dee6;
  --code-accent: #e4b36a;
  --code-green: #9cc79b;
  --good: #1e5a38;
  --good-soft: #e2eee5;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    color-scheme: dark;
    --paper: #141922;
    --paper-raised: #1c232e;
    --ink: #e7e4dc;
    --ink-soft: #b4b0a6;
    --neutral: #b7bec8;
    --rule: #2e3745;
    --seal: #e7b2ac;
    --seal-soft: #33231f;
    --bronze: #e0b86a;
    --bronze-soft: #2c2517;
    --code-bg: #10151d;
    --code-ink: #d5dbe3;
    --code-comment: #d7dee6;
    --good: #7dbe93;
    --good-soft: #1b2a20;
  }
}

:root[data-theme="light"] {
  color-scheme: light;
  --paper: #f6f7f4;
  --paper-raised: #ffffff;
  --ink: #1b222c;
  --ink-soft: #46505c;
  --neutral: #4e5966;
  --rule: #d6d9d2;
  --seal: #93312e;
  --seal-soft: #f3e4e2;
  --bronze: #6e5220;
  --bronze-soft: #f0e9da;
  --code-bg: #202834;
  --code-ink: #dde3ea;
  --code-comment: #d7dee6;
  --code-accent: #e4b36a;
  --code-green: #9cc79b;
  --good: #1e5a38;
  --good-soft: #e2eee5;
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --paper: #141922;
  --paper-raised: #1c232e;
  --ink: #e7e4dc;
  --ink-soft: #b4b0a6;
  --neutral: #b7bec8;
  --rule: #2e3745;
  --seal: #e7b2ac;
  --seal-soft: #33231f;
  --bronze: #e0b86a;
  --bronze-soft: #2c2517;
  --code-bg: #10151d;
  --code-ink: #d5dbe3;
  --code-comment: #d7dee6;
  --good: #7dbe93;
  --good-soft: #1b2a20;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: Charter, "Iowan Old Style", Palatino, "Palatino Linotype", Georgia, "Times New Roman", serif;
  font-size: 1.0625rem;
  line-height: 1.65;
}

.skip {
  position: absolute;
  left: 0.75rem;
  top: -4rem;
  background: var(--ink);
  color: var(--paper);
  padding: 0.55rem 0.8rem;
  z-index: 20;
}

.skip:focus { top: 0.75rem; }

:focus-visible {
  outline: 3px solid var(--seal);
  outline-offset: 2px;
}

.site-header {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem 1rem;
  padding: 0.4rem 1.1rem;
  background: var(--paper);
  border-bottom: 1px solid var(--rule);
}

.wordmark {
  font-family: Charter, "Iowan Old Style", Palatino, Georgia, serif;
  font-weight: 600;
  color: var(--ink);
  text-decoration: none;
  letter-spacing: -0.01em;
  padding: 0.55rem 0;
}

.nav {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.15rem 0.15rem;
  margin-left: auto;
}

.nav a {
  color: var(--ink);
  text-decoration: underline;
  text-underline-offset: 0.22em;
  font-family: ui-monospace, "Cascadia Code", "SF Mono", Menlo, Consolas, monospace;
  font-size: 0.78rem;
  letter-spacing: 0.02em;
  padding: 0.65rem 0.45rem;
  min-height: 44px;
  display: inline-flex;
  align-items: center;
}

.nav a[aria-current="page"] {
  color: var(--seal);
  text-decoration-thickness: 2px;
}

.theme-toggle {
  font-family: ui-monospace, Menlo, Consolas, monospace;
  font-size: 0.75rem;
  min-height: 44px;
  padding: 0.4rem 0.7rem;
  color: var(--ink);
  background: transparent;
  border: 1px solid var(--ink);
  cursor: pointer;
}

.home, .sheet-main {
  max-width: 40rem;
  margin: 0 auto;
  padding: 2.4rem 1.2rem 4.5rem;
}

.sheet { padding: 1.5rem 1.2rem 4rem; }

.eyebrow, .toc-label {
  font-family: ui-monospace, Menlo, Consolas, monospace;
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--bronze);
  margin: 0 0 0.8rem;
}

h1 {
  font-size: clamp(2.1rem, 6vw, 3.15rem);
  line-height: 1.12;
  font-weight: 600;
  letter-spacing: -0.02em;
  margin: 0 0 1rem;
  text-wrap: balance;
}

h1 em, .prose h2 em { color: var(--seal); }

.home h2, .prose h2, .prose h3 {
  line-height: 1.25;
  font-weight: 600;
  text-wrap: balance;
}

.home h2 { font-size: 1.45rem; margin: 2.4rem 0 0.8rem; }
.prose h2 { font-size: clamp(1.45rem, 3vw, 1.8rem); margin: 2.6rem 0 0.8rem; padding-top: 0.6rem; border-top: 2px solid var(--ink); }
.prose h3 { font-size: 1.2rem; margin: 2rem 0 0.5rem; }

p { margin: 0 0 1rem; }
.home p, .prose p { max-width: 40rem; }

.principles { margin: 0; padding-left: 1.4rem; }
.principles li { margin: 0.95rem 0; padding-left: 0.2rem; }
.principles li::marker, .prose ol li::marker { color: var(--seal); font-weight: 600; }

.actions { display: flex; flex-wrap: wrap; gap: 0.7rem; margin: 1.8rem 0 0.4rem; }

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0.55rem 1rem;
  background: var(--seal);
  color: var(--paper);
  text-decoration: none;
  border: 2px solid var(--seal);
  font-family: ui-monospace, Menlo, Consolas, monospace;
  font-size: 0.82rem;
  letter-spacing: 0.03em;
}

.button-quiet {
  background: transparent;
  color: var(--ink);
  border-color: var(--ink);
}

.papers { padding-left: 1.2rem; }
.papers li { margin: 0.7rem 0; }

.notice {
  border-left: 3px solid var(--bronze);
  padding: 0.15rem 0 0.15rem 0.9rem;
  margin: 0 0 1.4rem;
}

.spaced { margin-top: 2rem; }

.toc { margin: 0 auto 1.5rem; max-width: 40rem; }
.toc-list { list-style: none; margin: 0; padding: 0; }
.toc-list a {
  color: var(--ink);
  text-decoration: underline;
  text-underline-offset: 0.18em;
  font-size: 0.92rem;
}
.toc-h3 { margin-left: 0.9rem; }
.toc-list li { margin: 0.35rem 0; }

.source-line {
  font-family: ui-monospace, Menlo, Consolas, monospace;
  font-size: 0.82rem;
  margin-top: 2.5rem;
}

.prose hr { border: 0; border-top: 1px solid var(--rule); margin: 2rem 0; }

.prose pre, .paper pre, .scroll {
  max-width: min(100%, calc(100vw - 2.5rem));
  overflow-x: auto;
}

.prose pre {
  background: var(--code-bg);
  color: var(--code-ink);
  padding: 1rem 1.05rem;
  margin: 0 0 1.2rem;
  font-size: 0.82rem;
  line-height: 1.55;
}

/* Companion papers color comments for a dark code background.
   Italic at this size antialiases below the contrast threshold. */
.c { color: var(--code-comment); font-style: normal; }

code, pre, .nav, .theme-toggle, .eyebrow, .toc-label, .source-line, .button {
  font-family: ui-monospace, "Cascadia Code", "SF Mono", Menlo, Consolas, monospace;
}

.prose :not(pre) > code, .home :not(pre) > code, .paper :not(pre) > code {
  font-size: 0.88em;
  background: var(--paper-raised);
  border: 1px solid var(--rule);
  padding: 0.05em 0.28em;
  overflow-wrap: anywhere;
}

.site-footer {
  border-top: 1px solid var(--rule);
  padding: 1.4rem 1.2rem 2.4rem;
  color: var(--ink-soft);
  font-size: 0.92rem;
}

.site-footer p { margin: 0.35rem auto; max-width: 40rem; }
.site-footer a { color: var(--seal); }

@media (min-width: 1100px) {
  .sheet {
    max-width: 68rem;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 16rem minmax(0, 42rem);
    gap: 2rem;
    align-items: start;
    justify-content: center;
  }
  .toc {
    position: sticky;
    top: 1rem;
    max-height: calc(100vh - 2rem);
    overflow: auto;
    margin: 0;
    padding-top: 2rem;
  }
  .sheet-main { margin: 0; max-width: none; }
}

@media (max-width: 720px) {
  .nav { margin-left: 0; }
  .site-header { padding-inline: 0.8rem; }
  .home, .sheet-main { padding-inline: 1rem; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation: none !important;
    transition: none !important;
  }
}