/* ==========================================================================
   Footnotes Press — Publication & Splash Page Styles
   Editorial light & dark theming, fluid typography, and intrinsic CSS layout
   ========================================================================== */

:root {
  /* Light palette (warm archival newsprint) */
  --bg-light: #faf7f2;
  --surface-light: #f2ece1;
  --ink-light: #1c1917;
  --ink-muted-light: #57534e;
  --accent-light: #a63a24;
  --accent-hover-light: #8a2e1b;
  --hairline-light: #ddd5c7;

  /* Dark palette (warm evening study) */
  --bg-dark: #161412;
  --surface-dark: #211e1b;
  --ink-dark: #f3efe8;
  --ink-muted-dark: #b8b0a4;
  --accent-dark: #e07a5f;
  --accent-hover-dark: #ea9179;
  --hairline-dark: #38332e;

  /* Base light tokens */
  --color-bg: var(--bg-light);
  --color-surface: var(--surface-light);
  --color-ink: var(--ink-light);
  --color-ink-muted: var(--ink-muted-light);
  --color-accent: var(--accent-light);
  --color-accent-hover: var(--accent-hover-light);
  --color-hairline: var(--hairline-light);

  /* Typography stacks */
  --font-serif: "Iowan Old Style", "Palatino Linotype", Palatino, "Book Antiqua", Georgia, serif;
  --font-sans: system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-mono: ui-monospace, "SF Mono", Menlo, Consolas, monospace;

  /* Layout measure */
  --container-max: 44rem;
  --gutter: clamp(1.25rem, 4vw, 2.25rem);

  /* MANDATORY: Automatically adapt native UI to user system preferences */
  color-scheme: light dark;
}

/* Fallback for browsers without light-dark() support */
@media (prefers-color-scheme: dark) {
  :root {
    --color-bg: var(--bg-dark);
    --color-surface: var(--surface-dark);
    --color-ink: var(--ink-dark);
    --color-ink-muted: var(--ink-muted-dark);
    --color-accent: var(--accent-dark);
    --color-accent-hover: var(--accent-hover-dark);
    --color-hairline: var(--hairline-dark);
  }
}

@supports (color: light-dark(white, black)) {
  :root {
    --color-bg: light-dark(var(--bg-light), var(--bg-dark));
    --color-surface: light-dark(var(--surface-light), var(--surface-dark));
    --color-ink: light-dark(var(--ink-light), var(--ink-dark));
    --color-ink-muted: light-dark(var(--ink-muted-light), var(--ink-muted-dark));
    --color-accent: light-dark(var(--accent-light), var(--accent-dark));
    --color-accent-hover: light-dark(var(--accent-hover-light), var(--accent-hover-dark));
    --color-hairline: light-dark(var(--hairline-light), var(--hairline-dark));
  }
}

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

html {
  scroll-behavior: smooth;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
}

body {
  margin: 0;
  background-color: var(--color-bg);
  color: var(--color-ink);
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.65;
  text-align: start;
  overflow-wrap: break-word;
  -webkit-font-smoothing: antialiased;
}

svg {
  display: block;
  max-inline-size: 100%;
}

p,
h1,
h2 {
  margin-block-start: 0;
}

p {
  text-wrap: pretty;
}

h1,
h2 {
  font-family: var(--font-serif);
  font-weight: 600;
  letter-spacing: -0.02em;
  text-wrap: balance;
}

a {
  color: var(--color-accent);
  text-underline-offset: 0.2em;
  text-decoration-thickness: 0.08em;
}

a:hover {
  color: var(--color-accent-hover);
}

:where(a:any-link, [tabindex]):focus-visible {
  outline: 3px solid var(--color-accent);
  outline-offset: 3px;
}

:target {
  scroll-margin-block-start: 2rem;
}

/* Visually hidden utility (for accessible skip links) */
.visually-hidden:where(:not(:focus-within, :active)) {
  position: absolute !important;
  clip-path: inset(50%) !important;
  overflow: hidden !important;
  width: 1px !important;
  height: 1px !important;
  margin: -1px !important;
  padding: 0 !important;
  border: 0 !important;
  white-space: nowrap !important;
}

.skip-link:focus-visible {
  position: fixed;
  inset-block-start: 0.75rem;
  inset-inline-start: 0.75rem;
  z-index: 100;
  padding: 0.65rem 1rem;
  background-color: var(--color-ink);
  color: var(--color-bg);
  border-radius: 0.375rem;
  font-weight: 600;
  text-decoration: none;
}

/* Full-viewport editorial shell */
.page-shell {
  display: grid;
  grid-template-rows: auto 1fr auto;
  min-block-size: 100dvb;
}

.container {
  inline-size: min(100% - 2 * var(--gutter), var(--container-max));
  margin-inline: auto;
}

/* Header */
.site-header {
  border-block-end: 1px solid var(--color-hairline);
  padding-block: 0.9rem;
}

.header-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: safe center;
  justify-content: space-between;
  gap: 0.5rem 1.25rem;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  min-block-size: 44px;
  color: var(--color-ink);
  font-family: var(--font-serif);
  font-size: 1.15rem;
  font-weight: 700;
  text-decoration: none;
}

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

.domain-tag {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--color-ink-muted);
}

.nav-link {
  display: inline-flex;
  align-items: center;
  min-block-size: 44px;
  padding-inline: 0.25rem;
  font-size: 0.94rem;
  font-weight: 500;
  color: var(--color-ink-muted);
  text-decoration: none;
}

.nav-link:hover {
  color: var(--color-ink);
}

/* Main Home Content */
.site-main {
  display: grid;
  align-content: safe center;
  padding-block: clamp(2.25rem, 6vw, 4.5rem);
}

.home-stack {
  display: grid;
  gap: 1.5rem;
}

.splash-card,
.issue-feature {
  padding: clamp(1.5rem, 4vw, 2.5rem);
  background-color: var(--color-surface);
  border: 1px solid var(--color-hairline);
  border-radius: 0.65rem;
}

.eyebrow {
  display: inline-flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-block-end: 0.85rem;
}

.splash-title {
  /* Max <= 2.5 * min for WCAG 1.4.4 zoom compatibility */
  font-size: clamp(2.1rem, 1.4rem + 2.8vw, 3.6rem);
  line-height: 1.1;
  margin-block-end: 1.1rem;
}

.fn-sup {
  font-size: 0.55em;
  vertical-align: super;
  margin-inline-start: 0.12em;
}

.splash-title .fn-sup {
  font-size: 0.42em;
}

.fn-sup a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-inline-size: 24px;
  min-block-size: 24px;
  border-radius: 999px;
  font-family: var(--font-mono);
  font-weight: 700;
  text-decoration: none;
}

.fn-sup a:hover {
  text-decoration: underline;
}

.splash-lead {
  font-size: clamp(1.05rem, 0.98rem + 0.35vw, 1.2rem);
  color: var(--color-ink);
  max-inline-size: 56ch;
  margin-block-end: 0;
}

/* Latest Issue Feature Card */
.issue-title {
  font-size: clamp(1.35rem, 1.15rem + 1vw, 1.85rem);
  line-height: 1.22;
  margin-block-end: 0.75rem;
}

.issue-title a {
  color: var(--color-ink);
  text-decoration: none;
}

.issue-title a:hover {
  color: var(--color-accent);
  text-decoration: underline;
}

.issue-excerpt {
  color: var(--color-ink-muted);
  max-inline-size: 58ch;
  margin-block-end: 1.1rem;
}

.read-link,
.back-link {
  display: inline-flex;
  align-items: center;
  min-block-size: 44px;
  font-weight: 600;
  font-size: 0.96rem;
  text-decoration: none;
}

.read-link:hover,
.back-link:hover {
  text-decoration: underline;
}

/* Article Page */
.post-main {
  padding-block: clamp(2.25rem, 6vw, 4.5rem);
}

.post-article {
  --container-max: 40rem;
}

.post-header {
  margin-block-end: 2rem;
  padding-block-end: 1.5rem;
  border-block-end: 1px solid var(--color-hairline);
}

.post-title {
  /* Max <= 2.5 * min for WCAG 1.4.4 zoom compatibility */
  font-size: clamp(1.85rem, 1.35rem + 2vw, 2.85rem);
  line-height: 1.15;
  margin-block-end: 0;
}

.post-body {
  font-size: 1.06rem;
  line-height: 1.72;
  max-inline-size: 60ch;
}

.post-body p {
  margin-block-end: 1.35rem;
}

.post-body h2 {
  font-size: clamp(1.3rem, 1.15rem + 0.6vw, 1.6rem);
  line-height: 1.25;
  margin-block: 2.25rem 0.85rem;
}

.post-nav {
  margin-block-start: 2rem;
  padding-block-start: 1.25rem;
  border-block-start: 1px solid var(--color-hairline);
}

/* Footnotes block */
.fn-rule {
  inline-size: 4.5rem;
  block-size: 1px;
  border: 0;
  background-color: var(--color-hairline);
  margin-block: 1.75rem 1.25rem;
  margin-inline: 0;
}

.footnotes {
  font-size: 0.92rem;
  color: var(--color-ink-muted);
}

.fn-list {
  margin: 0;
  padding-inline-start: 1.25rem;
}

.fn-list li {
  padding: 0.35rem 0.5rem;
  border-radius: 0.35rem;
}

.fn-list li + li {
  margin-block-start: 0.35rem;
}

.fn-list li:target {
  background-color: var(--color-surface);
  outline: 1px solid var(--color-accent);
}

.splash-card .fn-list li:target {
  background-color: var(--color-bg);
}

.fn-back {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-inline-size: 24px;
  min-block-size: 24px;
  margin-inline-start: 0.25rem;
  text-decoration: none;
  font-family: var(--font-mono);
}

@media (pointer: coarse) {
  .fn-sup a,
  .fn-back {
    min-inline-size: 36px;
    min-block-size: 36px;
  }
}

/* Footer */
.site-footer {
  border-block-start: 1px solid var(--color-hairline);
  padding-block: 1.25rem;
  font-size: 0.88rem;
  color: var(--color-ink-muted);
}

.footer-inner p {
  margin: 0;
}

/* Forced Colors / High Contrast Mode */
@media (forced-colors: active) {
  .splash-card,
  .issue-feature,
  .fn-list li:target {
    border: 1px solid CanvasText;
  }
}