/* =========================================================
   PlexisSystems — Shared foundation (tokens, nav, footer, UI)
   ========================================================= */

:root{
  /* Color */
  --ink:        #172033;   /* primary text — near-black navy */
  --ink-soft:   #64748B;   /* secondary text — slate gray */
  --ink-faint:  #94A3B8;   /* tertiary / placeholder */
  --navy:       #102A43;   /* brand primary — deep navy */
  --navy-700:   #0B1F33;   /* darker navy, footer variant */
  --blue:       #2563EB;   /* primary buttons / links — bright blue */
  --blue-600:   #1D4ED8;   /* button hover — darker blue */
  --blue-100:   #EFF6FF;   /* pale blue section background */
  --amber:      #F59E0B;   /* accent — warm orange */
  --amber-600:  #D97706;
  --teal:       #0D9488;   /* success / positive */
  --teal-100:   #CCFBF1;
  --bg:         #F8FAFC;   /* page background — soft white */
  --surface:    #FFFFFF;   /* card background — pure white */
  --border:     #E2E8F0;   /* light gray-blue */
  --border-soft:#EDF2F7;
  --danger:     #DC2626;

  /* Type */
  --font-display: 'Fraunces', Georgia, serif;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'JetBrains Mono', 'Courier New', monospace;

  /* Scale */
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 22px;
  --shadow-sm: 0 1px 2px rgba(22,33,62,0.06);
  --shadow-md: 0 8px 24px rgba(22,33,62,0.08);
  --shadow-lg: 0 20px 48px rgba(22,33,62,0.12);
  --container: 1160px;
}

*, *::before, *::after{ box-sizing: border-box; }
html{ scroll-behavior: smooth; }

/* Guarantee the hidden attribute always hides an element, even if a class
   on the same element (e.g. .btn's display:inline-flex) has equal CSS
   specificity and would otherwise win the cascade. */
[hidden]{ display: none !important; }

fieldset{ border: none; margin: 0; padding: 0; min-width: 0; }
legend{ padding: 0; }

body{
  margin:0;
  font-family: var(--font-body);
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  line-height: 1.6;
}
img{ max-width:100%; display:block; }
a{ color: inherit; text-decoration:none; }
h1,h2,h3,h4{
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.15;
  margin: 0 0 .5em;
  color: var(--navy);
}
p{ margin: 0 0 1em; color: var(--ink-soft); }
ul{ margin:0; padding:0; list-style:none; }
button{ font-family: inherit; cursor:pointer; }
input, select, textarea{ font-family: inherit; font-size: 1rem; }

.container{
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 28px;
}
.eyebrow{
  display:inline-flex;
  align-items:center;
  gap:8px;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--amber-600);
  font-weight: 700;
  margin-bottom: 14px;
}
.eyebrow::before{
  content:'';
  width:16px; height:1px;
  background: var(--amber-600);
}

/* Buttons */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:8px;
  padding: 13px 26px;
  border-radius: 100px;
  font-weight: 600;
  font-size: .95rem;
  border: 1px solid transparent;
  transition: transform .15s ease, box-shadow .15s ease, background .15s ease, color .15s ease, border-color .15s ease;
  white-space: nowrap;
}
.btn-primary{
  background: var(--blue);
  color: #fff;
  box-shadow: var(--shadow-sm);
}
.btn-primary:hover{ background: var(--blue-600); box-shadow: var(--shadow-md); transform: translateY(-1px); }
.btn-amber{
  background: var(--amber);
  color: #fff;
}
.btn-amber:hover{ background: var(--amber-600); transform: translateY(-1px); box-shadow: var(--shadow-md); }
.btn-outline{
  background: transparent;
  color: var(--navy);
  border-color: var(--border);
}
.btn-outline:hover{ border-color: var(--blue); color: var(--blue); background: var(--surface); }
.btn-block{ width:100%; }
.btn-sm{ padding: 9px 18px; font-size: .85rem; }

/* Nav */
.site-header{
  position: sticky;
  top:0;
  z-index: 100;
  background: rgba(246,247,251,0.86);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border-soft);
}
.nav{
  display:flex;
  align-items:center;
  justify-content:space-between;
  padding: 16px 28px;
  max-width: var(--container);
  margin: 0 auto;
}
.brand{
  display:flex;
  align-items:center;
  gap:10px;
}
.brand-logo{
  height: 34px;
  width: auto;
  display:block;
}
.logo-chip{
  display:inline-flex;
  align-items:center;
  background: #fff;
  padding: 8px 14px;
  border-radius: 10px;
}
.nav-links{
  display:flex;
  align-items:center;
  gap: 30px;
}
.nav-links a{
  font-size: .92rem;
  font-weight: 500;
  color: var(--ink-soft);
  position: relative;
  padding: 6px 0;
  transition: color .15s ease;
}
.nav-links a:hover, .nav-links a.active{ color: var(--navy); }
.nav-links a.active::after{
  content:'';
  position:absolute;
  left:0; right:0; bottom:0;
  height:2px;
  background: var(--blue);
  border-radius: 2px;
}
.nav-cta{ display:flex; align-items:center; gap: 14px; }
.nav-toggle{
  display:none;
  width: 40px; height: 40px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--surface);
  align-items:center;
  justify-content:center;
  flex-direction:column;
  gap:4px;
}
.nav-toggle span{ width: 18px; height: 2px; background: var(--navy); border-radius:2px; }

@media (max-width: 900px){
  .nav-links{
    position: fixed;
    top: 65px; left:0; right:0;
    background: var(--surface);
    flex-direction: column;
    align-items: stretch;
    gap:0;
    padding: 8px 28px 18px;
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow-md);
    transform: translateY(-8px);
    opacity: 0;
    pointer-events: none;
    transition: transform .2s ease, opacity .2s ease;
  }
  .nav-links.open{ transform: translateY(0); opacity:1; pointer-events:auto; }
  .nav-links a{ padding: 12px 0; border-bottom: 1px solid var(--border-soft); }
  .nav-links a.active::after{ display:none; }
  .nav-cta .btn-outline{ display:none; }
  .nav-toggle{ display:flex; }
}

/* Footer */
.site-footer{
  background: var(--navy);
  color: #C9CEDD;
  margin-top: 120px;
}
.footer-top{
  max-width: var(--container);
  margin:0 auto;
  padding: 64px 28px 40px;
  display:grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 40px;
}
.footer-brand .brand{ margin-bottom: 14px; }
.footer-brand p{ color:#A7ADC2; max-width: 300px; }
.footer-col h4{
  font-family: var(--font-body);
  color:#fff;
  font-size: .82rem;
  letter-spacing:.06em;
  text-transform: uppercase;
  margin-bottom: 16px;
}
.footer-col a, .footer-col li{
  display:block;
  color: #A7ADC2;
  font-size: .92rem;
  margin-bottom: 12px;
  transition: color .15s ease;
}
.footer-col a:hover{ color: var(--amber); }
.footer-bottom{
  border-top: 1px solid rgba(255,255,255,0.1);
  padding: 22px 28px;
  max-width: var(--container);
  margin: 0 auto;
  display:flex;
  justify-content:space-between;
  align-items:center;
  font-size: .82rem;
  color: #7C82A0;
  flex-wrap:wrap;
  gap: 10px;
}
@media (max-width: 800px){
  .footer-top{ grid-template-columns: 1fr 1fr; }
}
@media (max-width: 520px){
  .footer-top{ grid-template-columns: 1fr; }
}

/* Section rhythm */
section{ padding: 96px 0; }
.section-head{
  max-width: 640px;
  margin: 0 0 56px;
}
.section-head.center{ margin-left:auto; margin-right:auto; text-align:center; }

/* Cards */
.card{
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
}

/* Utility */
.pill{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding: 5px 14px;
  border-radius: 100px;
  font-size: .78rem;
  font-weight: 600;
  background: var(--teal-100);
  color: var(--teal);
}
.grid-2{ display:grid; grid-template-columns: 1fr 1fr; gap: 32px; }
.grid-3{ display:grid; grid-template-columns: repeat(3,1fr); gap: 28px; }
.grid-4{ display:grid; grid-template-columns: repeat(4,1fr); gap: 24px; }
@media (max-width: 900px){
  .grid-3{ grid-template-columns: 1fr 1fr; }
  .grid-4{ grid-template-columns: 1fr 1fr; }
}
@media (max-width: 640px){
  .grid-2, .grid-3, .grid-4{ grid-template-columns: 1fr; }
  section{ padding: 64px 0; }
  .footer-top{ padding: 48px 24px 32px; }
}

/* Focus visibility */
a:focus-visible, button:focus-visible, input:focus-visible, textarea:focus-visible, select:focus-visible{
  outline: 2px solid var(--amber);
  outline-offset: 2px;
}

@media (prefers-reduced-motion: reduce){
  *{ animation-duration: .001ms !important; transition-duration: .001ms !important; scroll-behavior:auto !important; }
}

/* Reveal-on-scroll utility, used by common.js */
.reveal{ opacity:0; transform: translateY(16px); transition: opacity .6s ease, transform .6s ease; }
.reveal.in{ opacity:1; transform:none; }

/* Pale-blue alternating section background */
.section-pale{
  background: var(--blue-100);
  border-top: 1px solid var(--border-soft);
  border-bottom: 1px solid var(--border-soft);
}

/* Page banner (used on inner pages) */
.page-banner{
  padding: 64px 0 56px;
  border-bottom: 1px solid var(--border-soft);
}
.page-banner h1{ font-size: clamp(2.1rem, 4vw, 2.9rem); margin-bottom: 12px; }
.page-banner p{ max-width: 580px; font-size: 1.08rem; }

/* Node / connection motif (signature element, reused sparingly) */
.node-dot{
  width: 9px; height: 9px;
  border-radius: 50%;
  background: var(--amber);
  flex-shrink: 0;
}