/* Diogenes Protocol — calm, accessible, self-contained.
   Single source of truth. No theme dependencies. */

/* ---------- Color system ---------- */
:root{
  color-scheme: light dark;

  --bg: #fbf7e6;          /* warm paper */
  --fg: #151515;
  --muted: rgba(0,0,0,.72);

  --line: rgba(0,0,0,.12);
  --surface: rgba(0,0,0,.04);

  --link: #2346a8;
  --link-visited: #4a3f9c;
  --link-hover: #b85c00;

  --focus: #111;
  --shadow: rgba(0,0,0,.08);
}

@media (prefers-color-scheme: dark){
  :root{
    --bg: #0f0f10;
    --fg: #f2f2f2;
    --muted: rgba(255,255,255,.72);

    --line: rgba(255,255,255,.16);
    --surface: rgba(255,255,255,.06);

    --link: #9fb5ff;
    --link-visited: #c0a6ff;
    --link-hover: #ffb15a;

    --focus: #f2f2f2;
    --shadow: rgba(0,0,0,.35);
  }
}

/* ---------- Base ---------- */
*{ box-sizing: border-box; }

html{ scroll-behavior: smooth; }

body{
  margin: 0;
  color: var(--fg);
  background: var(--bg);
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, Ubuntu, Cantarell, "Noto Sans", Arial, sans-serif;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

a{
  color: var(--link);
  text-decoration-thickness: 2px;
  text-underline-offset: 2px;
}
a:visited{ color: var(--link-visited); }
a:hover{ color: var(--link-hover); }
a:focus-visible{
  outline: 2px solid var(--focus);
  outline-offset: 2px;
  border-radius: 8px;
}

/* Skip link */
.skip-link{
  position: absolute;
  left: -999px;
  top: auto;
  width: 1px;
  height: 1px;
  overflow: hidden;
}
.skip-link:focus{
  left: 1rem;
  top: 1rem;
  width: auto;
  height: auto;
  padding: .5rem .75rem;
  background: var(--bg);
  color: var(--fg);
  border: 2px solid var(--focus);
  border-radius: 12px;
  z-index: 9999;
}

/* ---------- Layout ---------- */
.page-header{
  padding: 1.35rem 1rem 0.75rem;
  border-bottom: 1px solid var(--line);
  background: transparent;
}

.project-name{
  margin: 0;
  font-size: clamp(1.35rem, 2.6vw, 1.9rem);
  letter-spacing: .2px;
}

.project-tagline{
  margin: .25rem 0 0;
  font-size: 1rem;
  color: var(--muted);
  font-weight: 500;
}

.main-content{
  max-width: 58rem;
  margin: 0 auto;
  padding: 1rem 1rem 3rem;
  font-size: 17px;
}

@media (max-width: 540px){
  .main-content{ font-size: 16px; }
}

/* ---------- Navigation ---------- */
.site-nav{
  display: flex;
  flex-wrap: wrap;
  gap: .55rem .65rem;
  padding: .75rem .85rem;
  margin: 0 0 1.1rem;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--surface);
  box-shadow: 0 1px 0 var(--shadow);
}

.site-nav a{
  display: inline-block;
  padding: .22rem .45rem;
  border-radius: 12px;
  font-weight: 650;
  text-decoration: none;
}

.site-nav a:hover{
  background: rgba(0,0,0,.06);
}
@media (prefers-color-scheme: dark){
  .site-nav a:hover{ background: rgba(255,255,255,.08); }
}

/* ---------- Typography ---------- */
p, li{
  line-height: 1.65;
}

h1, h2, h3, h4{
  margin: 1.6rem 0 .65rem;
  line-height: 1.25;
}

h1{ font-size: 1.55rem; }
h2{ font-size: 1.25rem; }
h3{ font-size: 1.1rem; }

hr{
  border: 0;
  border-top: 1px solid var(--line);
  margin: 1.3rem 0;
}

blockquote{
  margin: 1rem 0;
  padding: .25rem 0 .25rem .9rem;
  border-left: 4px solid var(--line);
  color: var(--muted);
}

ul, ol{
  padding-left: 1.25rem;
}

code{
  padding: .12rem .32rem;
  border-radius: 7px;
  background: rgba(0,0,0,.05);
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  font-size: .95em;
}
@media (prefers-color-scheme: dark){
  code{ background: rgba(255,255,255,.10); }
}

pre{
  padding: .95rem 1.05rem;
  border-radius: 16px;
  overflow: auto;
  border: 1px solid var(--line);
  background: rgba(0,0,0,.03);
}
@media (prefers-color-scheme: dark){
  pre{ background: rgba(255,255,255,.06); }
}
pre code{
  padding: 0;
  background: transparent;
}

/* Tables (if any) */
table{
  width: 100%;
  border-collapse: collapse;
  margin: 1rem 0;
}
th, td{
  border: 1px solid var(--line);
  padding: .5rem .6rem;
  vertical-align: top;
}
th{
  background: var(--surface);
  text-align: left;
}

/* ---------- Corner art (uses your pre-feathered PNG alpha) ---------- */
.corner-art{
  position: fixed;
  right: -70px;
  bottom: -55px;
  width: clamp(260px, 40vw, 540px);
  height: auto;

  pointer-events: none;

  /* Below content but visible through transparent surfaces */
  z-index: 0;

  opacity: 0.22;
  filter: blur(1.2px) saturate(0.70) contrast(0.90) brightness(1.02);
  mix-blend-mode: multiply;
}

@media (prefers-color-scheme: dark){
  .corner-art{
    opacity: 0.16;
    filter: blur(1.3px) saturate(0.62) contrast(0.88) brightness(0.95);
    mix-blend-mode: screen;
  }
}

@media (max-width: 520px){
  .corner-art{
    right: -110px;
    bottom: -90px;
    opacity: 0.12;
  }
}

/* Ensure content layers above the art */
.page-header,
.main-content{
  position: relative;
  z-index: 1;
}

/* Print: remove decoration */
@media print{
  .corner-art{ display: none; }
  body{ background: #fff; color: #000; }
  a{ color: #000; text-decoration: underline; }
}

/* P2_NAV */
nav a.is-active { text-decoration: underline; }
.nav-sep { opacity: 0.65; padding: 0 0.35rem; }
.page-nav { margin-top: 2rem; display: flex; justify-content: space-between; gap: 1rem; flex-wrap: wrap; }