/* ============================================================
   NetSSR — design tokens
   ============================================================ */
:root{
  --paper:        #F2F4EE;
  --paper-2:      #E7EBE1;
  --paper-3:      #DCE2D5;
  --ink:          #101715;
  --ink-soft:     #4B564F;
  --ink-faint:    #7C877E;
  --line:         #C7D0C0;
  --line-strong:  #A9B6A0;
  --signal:       #2E6F5E;
  --signal-deep:  #1D4A3D;
  --signal-soft:  rgba(46,111,94,0.10);
  --amber:        #B07C1E;
  --panel:        #101715;
  --panel-text:   #EFF3EA;
  --panel-line:   #2B362F;

  --font-display: 'Space Grotesk', 'Arial Narrow', sans-serif;
  --font-body:    'IBM Plex Sans', system-ui, sans-serif;
  --font-mono:    'IBM Plex Mono', 'SF Mono', Consolas, monospace;

  --max: 1120px;
  --radius: 3px;
}

*,*::before,*::after{ box-sizing:border-box; }
html{ scroll-behavior:smooth; }
@media (prefers-reduced-motion: reduce){
  html{ scroll-behavior:auto; }
  *,*::before,*::after{ animation-duration:0.001ms !important; animation-iteration-count:1 !important; transition-duration:0.001ms !important; }
}

body{
  margin:0;
  background:var(--paper);
  color:var(--ink);
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.55;
  -webkit-font-smoothing:antialiased;
}

a{ color:inherit; }
h1,h2,h3{ font-family:var(--font-display); margin:0 0 .5em; letter-spacing:-0.01em; }
p{ margin:0 0 1em; color:var(--ink-soft); }
.mono{ font-family:var(--font-mono); }

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

/* subtle paper grain, purely decorative */
.grain{
  position:fixed; inset:0; pointer-events:none; z-index:1000;
  opacity:.035; mix-blend-mode:multiply;
  background-image:url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='120' height='120'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/></filter><rect width='100%25' height='100%25' filter='url(%23n)'/></svg>");
}

/* ============================================================
   Header
   ============================================================ */
.site-header{
  position:sticky; top:0; z-index:100;
  display:flex; align-items:center; justify-content:space-between;
  padding:18px clamp(20px,4vw,56px);
  background:rgba(242,244,238,0.88);
  backdrop-filter:blur(8px);
  border-bottom:1px solid var(--line);
}
.brand{ display:flex; align-items:center; gap:8px; text-decoration:none; }
.brand-mark{ color:var(--signal); font-size:18px; }
.brand-name{ font-family:var(--font-display); font-weight:600; font-size:19px; letter-spacing:-0.01em; }

.site-nav{ display:flex; gap:28px; }
.site-nav a{
  text-decoration:none; font-size:14.5px; color:var(--ink-soft);
  border-bottom:1px solid transparent; padding-bottom:2px;
  transition:color .15s ease, border-color .15s ease;
}
.site-nav a:hover{ color:var(--ink); border-color:var(--signal); }

.nav-cta{
  font-family:var(--font-mono); font-size:13px; text-decoration:none;
  padding:8px 14px; border:1px solid var(--ink); border-radius:2px;
  transition:background .15s ease, color .15s ease;
  white-space:nowrap;
}
.nav-cta:hover{ background:var(--ink); color:var(--paper); }

@media (max-width:760px){
  .site-nav{ display:none; }
}

/* ============================================================
   Hero
   ============================================================ */
.hero{
  padding:64px clamp(20px,4vw,56px) 40px;
  border-bottom:1px solid var(--line);
}
.hero-inner{ max-width:var(--max); margin:0 auto; }

.rfc-block{
  font-family:var(--font-mono);
  font-size:12.5px;
  line-height:1.6;
  color:var(--ink-faint);
  white-space:pre;
  overflow-x:auto;
  margin:0 0 40px;
  padding-bottom:20px;
  border-bottom:1px dashed var(--line-strong);
}

.hero-title{
  font-size:clamp(38px,6vw,68px);
  font-weight:600;
  line-height:1.04;
  max-width:16ch;
  color:var(--ink);
}
.hero-title-accent{
  display:block;
  color:var(--signal-deep);
}

.hero-lede{
  font-size:clamp(16px,1.8vw,19px);
  max-width:56ch;
  color:var(--ink-soft);
  margin-top:20px;
}

.hero-actions{ display:flex; gap:14px; flex-wrap:wrap; margin:30px 0 34px; }
.btn{
  font-family:var(--font-mono);
  font-size:14px;
  text-decoration:none;
  padding:13px 22px;
  border-radius:2px;
  border:1px solid var(--ink);
  transition:background .15s ease, color .15s ease, transform .1s ease;
}
.btn-primary{ background:var(--ink); color:var(--paper); }
.btn-primary:hover{ background:var(--signal-deep); border-color:var(--signal-deep); }
.btn-ghost{ background:transparent; color:var(--ink); }
.btn-ghost:hover{ background:var(--paper-2); }
.btn:active{ transform:translateY(1px); }

.hero-status{
  display:flex; align-items:center; gap:10px; flex-wrap:wrap;
  font-size:12.5px; color:var(--ink-faint);
}
.hero-status .sep{ opacity:.5; }
.dot{
  width:7px; height:7px; border-radius:50%;
  background:var(--signal);
  box-shadow:0 0 0 0 var(--signal-soft);
  animation:pulse 2.4s ease-out infinite;
}
@keyframes pulse{
  0%{ box-shadow:0 0 0 0 rgba(46,111,94,.35); }
  70%{ box-shadow:0 0 0 8px rgba(46,111,94,0); }
  100%{ box-shadow:0 0 0 0 rgba(46,111,94,0); }
}

/* ============================================================
   Section shared
   ============================================================ */
section{ padding:80px clamp(20px,4vw,56px); }
.section-head{ max-width:var(--max); margin:0 auto 44px; }
.eyebrow{
  font-size:12.5px; letter-spacing:.06em; color:var(--signal-deep);
  text-transform:uppercase; margin-bottom:10px;
}
.section-head h2{ font-size:clamp(26px,3.4vw,38px); max-width:16ch; }
.section-intro{ max-width:60ch; font-size:16px; }

/* ============================================================
   Object / protocol diagram
   ============================================================ */
.object{ background:var(--paper); border-bottom:1px solid var(--line); }

.packet{ max-width:var(--max); margin:0 auto; }
.packet-caption{
  display:flex; justify-content:space-between;
  font-size:11px; color:var(--ink-faint); margin:0 0 6px; padding:0 2px;
}
.packet-row{
  display:flex; border:1px solid var(--ink); border-radius:2px; overflow:hidden;
}
.field{
  font-family:var(--font-mono);
  border:none; border-right:1px solid var(--ink);
  background:var(--paper-2);
  padding:26px 10px;
  cursor:pointer;
  font-size:12.5px;
  color:var(--ink);
  text-align:center;
  transition:background .15s ease, color .15s ease;
}
.field:last-child{ border-right:none; }
.field-1{ flex:0 0 30%; }
.field-2{ flex:0 0 24%; }
.field-3{ flex:0 0 28%; }
.field-4{ flex:0 0 18%; }
.field:hover, .field:focus-visible{ background:var(--signal); color:var(--panel-text); }
.field[aria-pressed="true"]{ background:var(--ink); color:var(--paper); }
.field-label{ letter-spacing:.03em; }

.field-detail{
  margin-top:22px;
  border:1px dashed var(--line-strong);
  padding:22px 26px;
  min-height:96px;
}
.field-detail-title{
  font-size:12px; color:var(--signal-deep); margin:0 0 10px;
}
.field-detail-text{ font-size:15.5px; max-width:62ch; margin:0; }

@media (max-width:640px){
  .packet-row{ flex-direction:column; }
  .field{ border-right:none; border-bottom:1px solid var(--ink); flex:none !important; }
  .field:last-child{ border-bottom:none; }
  .packet-caption{ display:none; }
}

/* ============================================================
   Activities / route table
   ============================================================ */
.activities{ background:var(--paper-2); }
.route-table{
  list-style:none; margin:0 auto; padding:0; max-width:var(--max);
  border-top:1px solid var(--line-strong);
}
.route{
  display:grid; grid-template-columns:150px 1fr;
  gap:24px; padding:26px 0;
  border-bottom:1px solid var(--line);
}
.route-tag{
  font-size:12.5px; color:var(--signal-deep);
  padding-top:3px;
}
.route-body h3{ font-size:19px; margin-bottom:6px; }
.route-body p{ margin:0; max-width:64ch; }

@media (max-width:640px){
  .route{ grid-template-columns:1fr; gap:6px; }
}

/* ============================================================
   Get involved
   ============================================================ */
.involved{ background:var(--panel); color:var(--panel-text); }
.section-head-light .eyebrow{ color:#8FC3B0; }
.section-head-light h2{ color:var(--panel-text); }

.cards{
  max-width:var(--max); margin:0 auto;
  display:grid; grid-template-columns:repeat(3,1fr); gap:1px;
  background:var(--panel-line);
  border:1px solid var(--panel-line);
}
.card{
  background:var(--panel);
  padding:32px 26px;
}
.card-index{
  font-size:12px; color:#8FC3B0; margin-bottom:16px;
}
.card h3{ color:var(--panel-text); font-size:19px; }
.card p{ color:#B7C0BA; font-size:14.5px; }
.card-link{
  display:inline-block; margin-top:10px;
  font-family:var(--font-mono); font-size:13.5px;
  text-decoration:none; color:#8FC3B0;
  border-bottom:1px solid transparent;
}
.card-link:hover{ border-color:#8FC3B0; }

@media (max-width:820px){
  .cards{ grid-template-columns:1fr; }
}

/* ============================================================
   Footer
   ============================================================ */
.site-footer{
  background:var(--panel); color:var(--panel-text);
  padding:56px clamp(20px,4vw,56px) 30px;
  border-top:1px solid var(--panel-line);
}
.footer-grid{
  max-width:var(--max); margin:0 auto;
  display:grid; grid-template-columns:1.4fr 1fr 1fr; gap:32px;
  padding-bottom:36px; border-bottom:1px solid var(--panel-line);
}
.footer-brand{ font-family:var(--font-display); font-size:19px; margin-bottom:8px; }
.footer-tagline{ color:#9FAAA3; font-size:14px; max-width:32ch; }
.footer-heading{ font-size:11px; letter-spacing:.08em; color:#8FC3B0; margin-bottom:12px; }
.footer-line{ color:#C4CCC6; font-size:13.5px; margin:0 0 6px; }
.footer-line a{ text-decoration:none; }
.footer-line a:hover{ color:#8FC3B0; }

.footer-bottom{
  max-width:var(--max); margin:20px auto 0;
  font-size:12px; color:#7C877E;
}

@media (max-width:640px){
  .footer-grid{ grid-template-columns:1fr; gap:24px; }
}