/* ==========================================================================
   VIDP — Verified Image Disclosure Protocol
   Design system: editorial confidence meets documentation rigor
   ========================================================================== */

/* Font declarations */
@import url('https://fonts.googleapis.com/css2?family=Fraunces:ital,opsz,wght@0,9..144,400;0,9..144,500;0,9..144,600;0,9..144,700;0,9..144,800;1,9..144,400;1,9..144,500&family=JetBrains+Mono:ital,wght@0,400;0,500;0,600;1,400&family=Source+Serif+4:ital,opsz,wght@0,8..60,400;0,8..60,500;0,8..60,600;0,8..60,700;1,8..60,400;1,8..60,500&display=swap');

/* ==========================================================================
   Design tokens
   ========================================================================== */
:root {
  /* Color system — paper-like background, deep ink text */
  --ink: #1a1a1a;
  --ink-soft: #2a2a2a;
  --ink-mute: #4a4a4a;
  --ink-fade: #6a6a6a;
  --ink-ghost: #8a8a8a;

  --paper: #faf8f5;
  --paper-warm: #f5f1ea;
  --paper-warmer: #ede7db;
  --paper-cold: #ffffff;

  --rule: #1a1a1a;
  --rule-soft: #d4cec1;
  --rule-ghost: #e8e3d8;

  /* VIDP pill tier colors — the accent system */
  --tier-0: #1565c0;
  --tier-0-soft: rgba(21, 101, 192, 0.08);
  --tier-1: #2e7d32;
  --tier-1-soft: rgba(46, 125, 50, 0.08);
  --tier-2: #f57c00;
  --tier-2-soft: rgba(245, 124, 0, 0.08);
  --tier-3: #c62828;
  --tier-3-soft: rgba(198, 40, 40, 0.08);

  /* Semantic colors */
  --link: #1565c0;
  --link-hover: #0d47a1;

  /* Typography */
  --font-display: 'Fraunces', Georgia, serif;
  --font-body: 'Source Serif 4', Georgia, serif;
  --font-mono: 'JetBrains Mono', ui-monospace, 'SF Mono', Menlo, monospace;

  /* Scale — informed by editorial typography */
  --step--2: 0.694rem;
  --step--1: 0.833rem;
  --step-0: 1rem;
  --step-1: 1.2rem;
  --step-2: 1.44rem;
  --step-3: 1.728rem;
  --step-4: 2.074rem;
  --step-5: 2.488rem;
  --step-6: 2.986rem;
  --step-7: 3.583rem;
  --step-8: 4.3rem;

  /* Spatial system */
  --space-2xs: 0.25rem;
  --space-xs: 0.5rem;
  --space-s: 0.75rem;
  --space-m: 1rem;
  --space-l: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4.5rem;
  --space-4xl: 6rem;
  --space-5xl: 9rem;

  /* Layout */
  --measure: 65ch;
  --measure-narrow: 50ch;
  --measure-wide: 80ch;
  --max-page: 72rem;
  --max-spec: 68rem;

  /* Motion */
  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);
  --ease-in-out: cubic-bezier(0.65, 0, 0.35, 1);
  --duration-fast: 180ms;
  --duration-mid: 320ms;
  --duration-slow: 600ms;
}

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

html {
  font-size: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 5rem;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-body);
  font-size: var(--step-0);
  line-height: 1.6;
  color: var(--ink);
  background: var(--paper);
  background-image:
    radial-gradient(circle at 20% 10%, rgba(245, 241, 234, 0.6) 0%, transparent 40%),
    radial-gradient(circle at 80% 90%, rgba(237, 231, 219, 0.4) 0%, transparent 50%);
  background-attachment: fixed;
  min-height: 100vh;
  overflow-x: hidden;
}

::selection {
  background: var(--ink);
  color: var(--paper);
}

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

/* ==========================================================================
   Typography
   ========================================================================== */
.display {
  font-family: var(--font-display);
  font-weight: 500;
  line-height: 1.02;
  letter-spacing: -0.02em;
  font-optical-sizing: auto;
}

h1, .h1 {
  font-family: var(--font-display);
  font-size: clamp(var(--step-5), 5vw + 1rem, var(--step-8));
  font-weight: 500;
  line-height: 1.02;
  letter-spacing: -0.025em;
  color: var(--ink);
  font-optical-sizing: auto;
  font-variation-settings: "opsz" 144;
}

h2, .h2 {
  font-family: var(--font-display);
  font-size: clamp(var(--step-3), 3vw, var(--step-5));
  font-weight: 500;
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--ink);
  font-optical-sizing: auto;
}

h3, .h3 {
  font-family: var(--font-display);
  font-size: var(--step-3);
  font-weight: 600;
  line-height: 1.2;
  letter-spacing: -0.015em;
  color: var(--ink);
}

h4, .h4 {
  font-family: var(--font-display);
  font-size: var(--step-2);
  font-weight: 600;
  line-height: 1.25;
  letter-spacing: -0.01em;
}

h5, .h5 {
  font-family: var(--font-display);
  font-size: var(--step-1);
  font-weight: 600;
  line-height: 1.3;
}

h6, .h6 {
  font-family: var(--font-mono);
  font-size: var(--step--1);
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-mute);
}

p {
  max-width: var(--measure);
  margin-bottom: var(--space-m);
  font-feature-settings: "kern", "liga", "clig", "calt", "onum";
}

p.lead {
  font-size: clamp(var(--step-1), 1.5vw + 0.5rem, var(--step-3));
  line-height: 1.4;
  font-weight: 400;
  color: var(--ink-soft);
  max-width: 38ch;
  font-family: var(--font-display);
  font-style: italic;
  font-variation-settings: "opsz" 72;
}

a {
  color: var(--link);
  text-decoration: underline;
  text-decoration-color: var(--rule-soft);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  transition: text-decoration-color var(--duration-fast) var(--ease-out), color var(--duration-fast) var(--ease-out);
}

a:hover {
  color: var(--link-hover);
  text-decoration-color: currentColor;
}

strong, b {
  font-weight: 600;
  color: var(--ink);
}

em, i {
  font-style: italic;
}

code {
  font-family: var(--font-mono);
  font-size: 0.9em;
  background: var(--paper-warm);
  padding: 0.1em 0.35em;
  border-radius: 3px;
  border: 1px solid var(--rule-ghost);
}

pre {
  font-family: var(--font-mono);
  font-size: var(--step--1);
  line-height: 1.6;
  background: var(--paper-warm);
  padding: var(--space-m);
  border-radius: 4px;
  overflow-x: auto;
  border: 1px solid var(--rule-ghost);
  margin-bottom: var(--space-m);
}

pre code {
  background: transparent;
  padding: 0;
  border: 0;
}

blockquote {
  border-left: 2px solid var(--ink);
  padding-left: var(--space-l);
  margin: var(--space-xl) 0;
  font-family: var(--font-display);
  font-style: italic;
  font-size: var(--step-1);
  line-height: 1.45;
  color: var(--ink-soft);
  max-width: var(--measure-narrow);
}

hr {
  border: 0;
  border-top: 1px solid var(--rule-soft);
  margin: var(--space-2xl) 0;
}

.hr-heavy {
  border-top: 1px solid var(--ink);
  margin: var(--space-3xl) 0;
}

ul, ol {
  margin-bottom: var(--space-m);
  padding-left: var(--space-l);
  max-width: var(--measure);
}

li {
  margin-bottom: var(--space-xs);
}

li::marker {
  color: var(--ink-fade);
}

/* Small caps & micro labels */
.eyebrow {
  font-family: var(--font-mono);
  font-size: var(--step--2);
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-mute);
  margin-bottom: var(--space-s);
}

.label {
  font-family: var(--font-mono);
  font-size: var(--step--1);
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

/* ==========================================================================
   Layout primitives
   ========================================================================== */
.container {
  width: 100%;
  max-width: var(--max-page);
  margin-inline: auto;
  padding-inline: clamp(var(--space-l), 4vw, var(--space-2xl));
}

.container-narrow {
  max-width: var(--max-spec);
}

.stack > * + * {
  margin-top: var(--space-m);
}

.stack-l > * + * {
  margin-top: var(--space-l);
}

.stack-xl > * + * {
  margin-top: var(--space-xl);
}

.cluster {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-s);
  align-items: center;
}

.grid {
  display: grid;
  gap: var(--space-l);
}

.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

@media (max-width: 768px) {
  .grid-2, .grid-3, .grid-4 {
    grid-template-columns: 1fr;
  }
}

section {
  padding-block: clamp(var(--space-2xl), 8vw, var(--space-5xl));
}

/* ==========================================================================
   VIDP Pills — visual component matching the spec
   ========================================================================== */
.pill {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: #FFFFFF;
  padding: 0.5rem 0.875rem;
  border-radius: 6px;
  white-space: nowrap;
  line-height: 1;
}

.pill-tier-0 { background: rgba(21, 101, 192, 0.75); }
.pill-tier-1 { background: rgba(46, 125, 50, 0.75); }
.pill-tier-2 { background: rgba(245, 124, 0, 0.75); }
.pill-tier-3 { background: rgba(198, 40, 40, 0.75); }

.pill-solid.pill-tier-0 { background: var(--tier-0); }
.pill-solid.pill-tier-1 { background: var(--tier-1); }
.pill-solid.pill-tier-2 { background: var(--tier-2); }
.pill-solid.pill-tier-3 { background: var(--tier-3); }

.pill-sm {
  font-size: 0.6875rem;
  padding: 0.35rem 0.65rem;
}

.pill-lg {
  font-size: 0.9375rem;
  padding: 0.625rem 1.125rem;
}

/* Pill groups/stacks */
.pill-stack {
  display: inline-flex;
  flex-direction: column;
  gap: 0.25rem;
  align-items: flex-end;
}

.pill-row {
  display: inline-flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  align-items: center;
}

/* ==========================================================================
   Navigation header
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(250, 248, 245, 0.85);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--rule-ghost);
}

.site-header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 4rem;
  padding-inline: clamp(var(--space-l), 4vw, var(--space-2xl));
  max-width: var(--max-page);
  margin-inline: auto;
}

.site-logo {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.0625rem;
  letter-spacing: -0.01em;
  color: var(--ink);
  text-decoration: none;
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
}

.site-logo:hover {
  color: var(--ink);
}

.site-logo .wordmark-full {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-fade);
}

@media (max-width: 620px) {
  .site-logo .wordmark-full {
    display: none;
  }
}

.site-nav {
  display: flex;
  gap: var(--space-l);
  align-items: center;
}

.site-nav a {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-mute);
  text-decoration: none;
  padding: 0.5rem 0;
  position: relative;
  transition: color var(--duration-fast) var(--ease-out);
}

.site-nav a:hover,
.site-nav a.active {
  color: var(--ink);
}

.site-nav a.active::after {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 1px;
  background: var(--ink);
}

@media (max-width: 768px) {
  .site-nav {
    gap: var(--space-m);
  }
  .site-nav a:not(.nav-cta) {
    display: none;
  }
}

.nav-cta {
  padding: 0.5rem 0.875rem !important;
  background: var(--ink);
  color: var(--paper) !important;
  border-radius: 3px;
  transition: background var(--duration-fast) var(--ease-out), color var(--duration-fast) var(--ease-out) !important;
}

.nav-cta:hover {
  background: var(--tier-0);
  color: var(--paper) !important;
}

.nav-cta.active::after {
  display: none;
}

/* ==========================================================================
   Buttons
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding: 0.875rem 1.5rem;
  border: 1px solid var(--ink);
  background: var(--ink);
  color: var(--paper);
  text-decoration: none;
  border-radius: 3px;
  cursor: pointer;
  transition: all var(--duration-fast) var(--ease-out);
}

.btn:hover {
  background: var(--paper);
  color: var(--ink);
}

.btn-outline {
  background: transparent;
  color: var(--ink);
}

.btn-outline:hover {
  background: var(--ink);
  color: var(--paper);
}

.btn-ghost {
  background: transparent;
  border-color: transparent;
  color: var(--ink);
}

.btn-ghost:hover {
  background: var(--paper-warm);
  color: var(--ink);
  border-color: var(--rule-soft);
}

.btn-link {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink);
  text-decoration: none;
  padding: 0.5rem 0;
  border-bottom: 1px solid var(--ink);
  transition: gap var(--duration-fast) var(--ease-out);
}

.btn-link:hover {
  color: var(--ink);
  gap: 0.65rem;
}

.btn-link::after {
  content: '→';
  display: inline-block;
  transition: transform var(--duration-fast) var(--ease-out);
}

/* ==========================================================================
   Footer
   ========================================================================== */
.site-footer {
  border-top: 1px solid var(--ink);
  padding-block: var(--space-2xl) var(--space-xl);
  margin-top: var(--space-5xl);
  background: var(--paper-warm);
}

.site-footer-inner {
  max-width: var(--max-page);
  margin-inline: auto;
  padding-inline: clamp(var(--space-l), 4vw, var(--space-2xl));
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--space-2xl);
  margin-bottom: var(--space-2xl);
}

@media (max-width: 768px) {
  .site-footer-inner {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-xl);
  }
}

.footer-brand h4 {
  font-family: var(--font-display);
  font-size: var(--step-2);
  font-weight: 600;
  margin-bottom: var(--space-s);
}

.footer-brand p {
  font-size: var(--step--1);
  color: var(--ink-mute);
  max-width: 32ch;
  font-style: italic;
  font-family: var(--font-display);
}

.footer-col h5 {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-fade);
  margin-bottom: var(--space-m);
}

.footer-col ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.footer-col li {
  margin-bottom: var(--space-xs);
}

.footer-col a {
  font-size: var(--step--1);
  color: var(--ink-soft);
  text-decoration: none;
  transition: color var(--duration-fast) var(--ease-out);
}

.footer-col a:hover {
  color: var(--ink);
  text-decoration: underline;
  text-underline-offset: 2px;
}

.footer-meta {
  max-width: var(--max-page);
  margin-inline: auto;
  padding-inline: clamp(var(--space-l), 4vw, var(--space-2xl));
  padding-top: var(--space-l);
  border-top: 1px solid var(--rule-soft);
  display: flex;
  justify-content: space-between;
  gap: var(--space-m);
  flex-wrap: wrap;
  font-family: var(--font-mono);
  font-size: var(--step--2);
  letter-spacing: 0.04em;
  color: var(--ink-fade);
}

.footer-meta a {
  color: var(--ink-fade);
  text-decoration: none;
}

.footer-meta a:hover {
  color: var(--ink);
}

/* ==========================================================================
   Focus states (accessibility)
   ========================================================================== */
:focus-visible {
  outline: 2px solid var(--tier-0);
  outline-offset: 3px;
  border-radius: 2px;
}

.btn:focus-visible,
.nav-cta:focus-visible {
  outline-offset: 2px;
}

/* ==========================================================================
   Utilities
   ========================================================================== */
.text-center { text-align: center; }
.text-mute { color: var(--ink-mute); }
.text-fade { color: var(--ink-fade); }

.hide-sm { display: initial; }
.show-sm { display: none; }

@media (max-width: 768px) {
  .hide-sm { display: none; }
  .show-sm { display: initial; }
}

/* Motion — respect reduced motion preference */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* Print styles for the specification */
@media print {
  .site-header, .site-footer, .no-print {
    display: none !important;
  }
  body {
    background: white;
    color: black;
    font-size: 10.5pt;
  }
  h1, h2, h3, h4, h5, h6 {
    page-break-after: avoid;
  }
  p, li {
    page-break-inside: avoid;
  }
}