/* ============================================================
   base.css — Foundations
   CSS custom properties (design tokens), modest reset, base
   typography, and page-frame layout. The aesthetic target is
   an institutional library catalog: warm paper-cream
   background, deep oxblood as the single accent color, refined
   serif headings paired with a humanist sans body face.
   ============================================================ */

/* ---- Design tokens -------------------------------------- */
:root {
  /* Surfaces — warm cream paper feel */
  --color-bg:           #f4ede0;
  --color-bg-deep:      #ebe2cf;
  --color-card:         #ffffff;
  --color-card-alt:     #faf6ed;

  /* Text */
  --color-text:         #1a1612;
  --color-text-muted:   #6b6359;
  --color-text-subtle:  #908778;

  /* Borders & dividers */
  --color-border:       #d8cdb6;
  --color-border-strong:#b8a98d;

  /* Brand & accents — institutional oxblood */
  --color-accent:       #7a2e2e;
  --color-accent-hover: #5e2222;
  --color-accent-soft:  #ede0e0;

  /* Status colors — muted, not garish */
  --color-success:      #4a6741;
  --color-success-soft: #e2e9d8;
  --color-warning:      #8a5a1a;
  --color-warning-soft: #f4ead4;
  --color-danger:       #8a2a2a;
  --color-danger-soft:  #f1dada;
  --color-info:         #3d5566;
  --color-info-soft:    #dde6ee;

  /* Type scale */
  --font-display: 'Fraunces', 'Source Serif Pro', Georgia, serif;
  --font-body:    'IBM Plex Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono:    'IBM Plex Mono', ui-monospace, 'SF Mono', Menlo, monospace;

  /* Spacing scale (rem) */
  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-5:  1.5rem;
  --space-6:  2rem;
  --space-7:  3rem;
  --space-8:  4rem;

  /* Radii — kept tight for institutional feel */
  --radius-sm:  2px;
  --radius-md:  4px;
  --radius-lg:  6px;

  /* Shadows */
  --shadow-sm:  0 1px 2px rgba(40, 28, 14, 0.06);
  --shadow-md:  0 2px 6px rgba(40, 28, 14, 0.08), 0 1px 2px rgba(40, 28, 14, 0.04);
  --shadow-lg:  0 12px 32px rgba(40, 28, 14, 0.18), 0 2px 8px rgba(40, 28, 14, 0.08);

  /* Transitions */
  --t-fast: 120ms ease;
  --t-base: 200ms ease;
}

/* ---- Reset --------------------------------------------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body, h1, h2, h3, h4, h5, h6, p, ul, ol, figure, blockquote {
  margin: 0;
}
ul, ol { padding: 0; list-style: none; }
img, svg { display: block; max-width: 100%; }
button, input, select, textarea { font: inherit; color: inherit; }
button { background: none; border: 0; cursor: pointer; }
a { color: inherit; }

/* ---- Base typography ----------------------------------- */
html, body {
  height: 100%;
}

body {
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.55;
  color: var(--color-text);
  background-color: var(--color-bg);
  /* Subtle paper texture via layered gradient noise.
     Two near-transparent radial gradients give the cream
     surface a hint of variation without being busy. */
  background-image:
    radial-gradient(at 18% 12%, rgba(122, 46, 46, 0.04) 0, transparent 35%),
    radial-gradient(at 82% 88%, rgba(60, 40, 20, 0.05) 0, transparent 40%);
  background-attachment: fixed;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 500;
  letter-spacing: -0.01em;
  color: var(--color-text);
}

h1 {
  font-size: clamp(1.75rem, 2.5vw + 1rem, 2.5rem);
  line-height: 1.1;
  font-variation-settings: 'opsz' 144, 'SOFT' 30;
}

h2 {
  font-size: 1.5rem;
  line-height: 1.2;
  font-variation-settings: 'opsz' 100;
}

h3 {
  font-size: 1.125rem;
  line-height: 1.3;
}

p { color: var(--color-text); }

a {
  color: var(--color-accent);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 2px;
  transition: color var(--t-fast);
}
a:hover { color: var(--color-accent-hover); }

code, .mono {
  font-family: var(--font-mono);
  font-size: 0.9em;
  letter-spacing: -0.01em;
}

/* ---- Focus outline (accessibility) --------------------- */
:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* ---- Page frame ---------------------------------------- */
.page {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

.page__main {
  flex: 1;
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--space-7) var(--space-5);
}

.page__footer {
  border-top: 1px solid var(--color-border);
  padding: var(--space-5);
  text-align: center;
  font-size: 0.8125rem;
  color: var(--color-text-subtle);
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.page__footer a {
  color: var(--color-text-subtle);
  text-decoration: underline;
  text-decoration-color: var(--color-border-strong);
}

/* ---- Page header section (within .page__main) ---------- */
.page-header {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: end;
  gap: var(--space-5);
  padding-bottom: var(--space-5);
  margin-bottom: var(--space-6);
  border-bottom: 1px solid var(--color-border);
}

.page-header__title { margin-bottom: var(--space-1); }

.page-header__eyebrow {
  font-family: var(--font-body);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: var(--space-2);
}

.page-header__sub {
  color: var(--color-text-muted);
  font-size: 0.95rem;
  max-width: 60ch;
}

.page-header__actions {
  display: flex;
  gap: var(--space-3);
  flex-wrap: wrap;
}

/* ---- Section spacing ----------------------------------- */
.section + .section { margin-top: var(--space-7); }

.section__head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: var(--space-4);
  margin-bottom: var(--space-4);
  padding-bottom: var(--space-3);
  border-bottom: 1px solid var(--color-border);
}

.section__title {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 500;
}

/* ---- Utility classes ----------------------------------- */
.muted   { color: var(--color-text-muted); }
.subtle  { color: var(--color-text-subtle); }
.center  { text-align: center; }
.hidden  { display: none !important; }

/* "Eyebrow" small label above headings — small caps treatment. */
.eyebrow {
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--color-text-subtle);
}

/* Responsive page padding */
@media (max-width: 720px) {
  .page__main { padding: var(--space-5) var(--space-4); }
  h1 { font-size: 1.75rem; }
}