/* =========================================================
   SKOP Systems — styles
   Dark, minimal, technical, ancient-greek-tinged.
   ========================================================= */

:root {
  /* Palette */
  --bg-0: #07090d;          /* deepest */
  --bg-1: #0a0d12;          /* page */
  --bg-2: #0f131a;          /* card */
  --bg-3: #141923;          /* raised */
  --line: rgba(180, 200, 230, 0.08);
  --line-strong: rgba(180, 200, 230, 0.16);

  --ink: #ece7da;           /* warm off-white */
  --ink-soft: #b9b6ac;
  --ink-mute: #7a7a73;
  --ink-faint: rgba(236, 231, 218, 0.42);

  --accent: #6db3ff;        /* electric blue */
  --accent-2: #6fe3d4;      /* muted cyan */
  --accent-3: #d8b270;      /* amber-gold */
  --accent-glow: rgba(109, 179, 255, 0.35);

  /* Type */
  --font-sans: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, "SFMono-Regular", Menlo, monospace;
  --font-serif: "Cormorant Garamond", "EB Garamond", Georgia, serif;

  /* Layout */
  --max: 1200px;
  --pad-x: clamp(20px, 4vw, 56px);
  --radius: 14px;
  --radius-sm: 8px;

  /* Motion */
  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg-1);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

body {
  min-height: 100vh;
  overflow-x: hidden;
  background:
    radial-gradient(1200px 700px at 80% -10%, rgba(109, 179, 255, 0.07), transparent 60%),
    radial-gradient(900px 500px at -10% 30%, rgba(111, 227, 212, 0.05), transparent 60%),
    var(--bg-1);
}

a { color: inherit; text-decoration: none; }
img, svg { display: block; max-width: 100%; }

/* ---------- Ambient / grain ---------- */
.ambient {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}
.ambient-word {
  position: absolute;
  font-family: var(--font-serif);
  font-style: italic;
  color: rgba(236, 231, 218, 0.035);
  font-size: clamp(120px, 18vw, 320px);
  letter-spacing: -0.02em;
  user-select: none;
  white-space: nowrap;
  line-height: 1;
}
.w1 { top: 6vh;   left: -4vw; }
.w2 { top: 38vh;  right: -8vw; }
.w3 { top: 72vh;  left: 10vw;  font-size: clamp(80px, 12vw, 200px); }
.w4 { top: 120vh; right: 4vw; }
.w5 { top: 170vh; left: -6vw; }

.grain {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 1;
  opacity: 0.035;
  mix-blend-mode: overlay;
  background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='160' height='160'><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: 50;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px var(--pad-x);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  background: linear-gradient(to bottom, rgba(10, 13, 18, 0.78), rgba(10, 13, 18, 0.35));
  border-bottom: 1px solid var(--line);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
}
.brand-mark {
  width: 30px;
  height: 30px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}
.brand-mark .mark-ring { fill: none; stroke: var(--line-strong); stroke-width: 1; }
.brand-mark .mark-dot  { fill: var(--accent); }
.brand-mark .mark-node { fill: var(--ink-soft); }
.brand-mark .mark-edge { fill: none; stroke: var(--ink-mute); stroke-width: 0.8; }
.brand-text { display: inline-flex; align-items: baseline; gap: 8px; }
.brand-name {
  font-weight: 600;
  letter-spacing: 0.18em;
  font-size: 14px;
}
.brand-sub {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ink-mute);
  letter-spacing: 0.06em;
}

.site-nav {
  display: flex;
  gap: 28px;
  align-items: center;
  font-size: 13px;
}
.site-nav a {
  color: var(--ink-soft);
  position: relative;
  padding: 6px 0;
  transition: color 180ms var(--ease);
}
.site-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 0;
  height: 1px;
  background: var(--accent);
  transition: width 220ms var(--ease);
}
.site-nav a:hover { color: var(--ink); }
.site-nav a:hover::after { width: 100%; }

.nav-cta {
  padding: 8px 14px !important;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  color: var(--ink) !important;
}
.nav-cta::after { display: none; }
.nav-cta:hover {
  border-color: var(--accent);
  background: rgba(109, 179, 255, 0.06);
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 13px 20px;
  font-size: 14px;
  font-weight: 500;
  border-radius: 999px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 220ms var(--ease), background 220ms var(--ease),
              border-color 220ms var(--ease), color 220ms var(--ease),
              box-shadow 220ms var(--ease);
  letter-spacing: 0.01em;
  position: relative;
  isolation: isolate;
}
.btn-primary {
  background: linear-gradient(180deg, #1b2333, #11161f);
  border-color: rgba(109, 179, 255, 0.35);
  color: var(--ink);
  box-shadow: 0 0 0 1px rgba(109, 179, 255, 0.05) inset,
              0 8px 30px -12px var(--accent-glow);
}
.btn-primary:hover {
  border-color: var(--accent);
  box-shadow: 0 0 0 1px rgba(109, 179, 255, 0.15) inset,
              0 12px 40px -10px var(--accent-glow);
  transform: translateY(-1px);
}
.btn-ghost {
  background: transparent;
  border-color: var(--line-strong);
  color: var(--ink-soft);
}
.btn-ghost:hover {
  border-color: var(--ink-soft);
  color: var(--ink);
}
.btn-large {
  padding: 16px 26px;
  font-size: 15px;
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  min-height: clamp(620px, 92vh, 920px);
  display: flex;
  align-items: center;
  padding: clamp(60px, 10vh, 120px) var(--pad-x) clamp(60px, 8vh, 100px);
  overflow: hidden;
}

#topology {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 1;
  opacity: 0.95;
}

.hero-vignette {
  position: absolute;
  inset: 0;
  z-index: 2;
  pointer-events: none;
  background:
    radial-gradient(ellipse at center, transparent 30%, rgba(7,9,13,0.55) 75%, var(--bg-1) 100%),
    linear-gradient(to bottom, rgba(7,9,13,0.0) 60%, var(--bg-1) 100%);
}

.hero-lens {
  position: absolute;
  inset: 0;
  z-index: 3;
  pointer-events: none;
  background: radial-gradient(
    circle 320px at var(--mx, 50%) var(--my, 50%),
    rgba(109, 179, 255, 0.10),
    transparent 70%
  );
  transition: background-position 80ms linear;
  mix-blend-mode: screen;
}

.hero-content {
  position: relative;
  z-index: 4;
  max-width: var(--max);
  margin: 0 auto;
  width: 100%;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  padding: 7px 14px 7px 12px;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  background: rgba(15, 19, 26, 0.55);
  backdrop-filter: blur(6px);
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ink-soft);
  margin-bottom: 28px;
  animation: fadeUp 900ms var(--ease) both;
}
.eyebrow-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 14px var(--accent-glow);
  animation: pulse 2.4s ease-in-out infinite;
}
.eyebrow-greek {
  font-family: var(--font-serif);
  font-style: italic;
  font-size: 14px;
  color: var(--accent-3);
}
.eyebrow-sep { color: var(--ink-mute); }
.eyebrow-en { color: var(--ink-mute); }

.hero-title {
  font-size: clamp(38px, 6.4vw, 84px);
  line-height: 1.02;
  letter-spacing: -0.025em;
  font-weight: 500;
  margin: 0 0 24px;
  max-width: 18ch;
  animation: fadeUp 1000ms 80ms var(--ease) both;
}
.hero-title .accent {
  font-family: var(--font-serif);
  font-style: italic;
  font-weight: 500;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-sub {
  max-width: 58ch;
  color: var(--ink-soft);
  font-size: clamp(15px, 1.4vw, 18px);
  line-height: 1.65;
  margin: 0 0 36px;
  animation: fadeUp 1000ms 160ms var(--ease) both;
}

.hero-ctas {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
  animation: fadeUp 1000ms 240ms var(--ease) both;
}

.hero-meta {
  margin-top: clamp(36px, 7vh, 80px);
  display: flex;
  align-items: center;
  gap: 16px;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--ink-mute);
  text-transform: uppercase;
  letter-spacing: 0.12em;
  animation: fadeUp 1000ms 320ms var(--ease) both;
}
.meta-bar {
  width: 140px;
  height: 1px;
  background: var(--line-strong);
  overflow: hidden;
  position: relative;
}
.meta-bar-fill {
  position: absolute;
  inset: 0;
  width: 30%;
  background: linear-gradient(90deg, var(--accent), transparent);
  animation: scan 6s linear infinite;
}
.meta-coord { color: var(--ink-faint); }

/* ---------- Sections ---------- */
.section {
  position: relative;
  z-index: 4;
  padding: clamp(80px, 14vh, 160px) var(--pad-x);
  max-width: var(--max);
  margin: 0 auto;
}

.section-head {
  max-width: 760px;
  margin-bottom: 56px;
}
.section-kicker {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--accent-3);
  margin-bottom: 18px;
}
.section-title {
  font-size: clamp(30px, 4.4vw, 56px);
  line-height: 1.06;
  letter-spacing: -0.022em;
  font-weight: 500;
  margin: 0 0 18px;
}
.section-title .greek {
  font-family: var(--font-serif);
  font-style: italic;
  color: var(--accent-2);
  font-weight: 500;
}
.section-lede {
  color: var(--ink-soft);
  font-size: clamp(15px, 1.3vw, 17px);
  line-height: 1.7;
  max-width: 60ch;
  margin: 0;
}

/* ---------- Cards (Meaning) ---------- */
.cards {
  display: grid;
  gap: 20px;
}
.cards.three {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}
@media (max-width: 900px) {
  .cards.three { grid-template-columns: 1fr; }
}

.card {
  position: relative;
  display: flex;
  flex-direction: column;
  padding: 28px 26px 22px;
  background: linear-gradient(180deg, rgba(20, 25, 35, 0.6), rgba(15, 19, 26, 0.55));
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  transition: transform 320ms var(--ease), border-color 320ms var(--ease),
              background 320ms var(--ease);
}
.card::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(400px 200px at var(--cx, 50%) var(--cy, 0%),
              rgba(109, 179, 255, 0.08), transparent 60%);
  opacity: 0;
  transition: opacity 320ms var(--ease);
  pointer-events: none;
}
.card:hover {
  transform: translateY(-3px);
  border-color: var(--line-strong);
}
.card:hover::before { opacity: 1; }

.card-num {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--ink-mute);
  margin-bottom: 18px;
}
.card-title {
  font-size: 22px;
  font-weight: 500;
  margin: 0 0 8px;
  letter-spacing: -0.01em;
}
.card-body {
  color: var(--ink-soft);
  margin: 0 0 22px;
  font-size: 14.5px;
  line-height: 1.6;
}
.card-viz {
  margin-top: auto;
  border-top: 1px solid var(--line);
  padding-top: 18px;
}
.card-viz svg { width: 100%; height: 60px; }

.viz-node { fill: var(--ink-soft); }
.viz-node-primary { fill: var(--accent); filter: drop-shadow(0 0 6px var(--accent-glow)); }
.viz-edge { fill: none; stroke: var(--line-strong); stroke-width: 1; }
.viz-pulse { fill: var(--accent); filter: drop-shadow(0 0 4px var(--accent-glow)); }
.viz-ring { fill: none; stroke: var(--line-strong); stroke-width: 1; }
.card:nth-child(3) .viz-ring:nth-of-type(1) { animation: ringPulse 4s ease-in-out infinite; }
.card:nth-child(3) .viz-ring:nth-of-type(2) { animation: ringPulse 4s ease-in-out infinite 0.6s; }
.card:nth-child(3) .viz-ring:nth-of-type(3) { animation: ringPulse 4s ease-in-out infinite 1.2s; }

/* ---------- Principles ---------- */
.principles {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}
@media (max-width: 760px) {
  .principles { grid-template-columns: 1fr; }
}
.principle {
  background: var(--bg-1);
  padding: 36px 32px;
  position: relative;
  transition: background 320ms var(--ease);
}
.principle:hover {
  background: var(--bg-2);
}
.principle-index {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.22em;
  color: var(--accent);
  margin-bottom: 14px;
}
.principle-title {
  font-size: 20px;
  font-weight: 500;
  margin: 0 0 10px;
  letter-spacing: -0.01em;
}
.principle-body {
  color: var(--ink-soft);
  font-size: 14.5px;
  line-height: 1.65;
  margin: 0;
  max-width: 46ch;
}

/* ---------- Tags ---------- */
.tags {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}
.tag {
  padding: 10px 18px;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  font-size: 13.5px;
  color: var(--ink-soft);
  background: rgba(15, 19, 26, 0.5);
  font-family: var(--font-mono);
  letter-spacing: 0.01em;
  transition: border-color 220ms var(--ease), color 220ms var(--ease),
              background 220ms var(--ease), transform 220ms var(--ease);
  cursor: default;
}
.tag:hover {
  border-color: var(--accent);
  color: var(--ink);
  background: rgba(109, 179, 255, 0.06);
  transform: translateY(-1px);
}

/* ---------- Final CTA ---------- */
.cta {
  text-align: center;
  padding-top: clamp(100px, 16vh, 180px);
  padding-bottom: clamp(120px, 18vh, 200px);
  border-top: 1px solid var(--line);
  margin-top: 60px;
}
.cta-inner {
  max-width: 760px;
  margin: 0 auto;
}
.cta-title {
  font-size: clamp(32px, 5.2vw, 64px);
  line-height: 1.06;
  letter-spacing: -0.022em;
  font-weight: 500;
  margin: 18px 0 22px;
}
.cta-title .accent {
  font-family: var(--font-serif);
  font-style: italic;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.cta-body {
  color: var(--ink-soft);
  font-size: clamp(15px, 1.3vw, 17px);
  line-height: 1.65;
  margin: 0 0 36px;
  max-width: 52ch;
  margin-inline: auto;
}

/* ---------- Footer ---------- */
.site-footer {
  position: relative;
  z-index: 4;
  border-top: 1px solid var(--line);
  padding: 32px var(--pad-x);
}
.footer-inner {
  max-width: var(--max);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}
.footer-brand {
  display: inline-flex;
  align-items: baseline;
  gap: 14px;
}
.footer-brand .brand-name {
  letter-spacing: 0.2em;
  font-size: 13px;
}
.footer-tag {
  font-family: var(--font-serif);
  font-style: italic;
  color: var(--ink-mute);
  font-size: 13px;
}
.footer-meta {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--ink-mute);
  letter-spacing: 0.05em;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}
.footer-dot { color: var(--line-strong); }

/* ---------- Reveal ---------- */
.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 700ms var(--ease), transform 700ms var(--ease);
  transition-delay: var(--delay, 0ms);
}
.reveal.in {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- Keyframes ---------- */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(14px); }
  to   { opacity: 1; transform: translateY(0); }
}
@keyframes pulse {
  0%, 100% { transform: scale(1);    opacity: 1;   }
  50%      { transform: scale(1.35); opacity: 0.6; }
}
@keyframes scan {
  0%   { transform: translateX(-100%); }
  100% { transform: translateX(400%); }
}
@keyframes ringPulse {
  0%, 100% { opacity: 0.25; }
  50%      { opacity: 0.9; }
}

/* ---------- Responsive ---------- */
@media (max-width: 720px) {
  .site-nav { gap: 16px; font-size: 12px; }
  .site-nav a:not(.nav-cta) { display: none; }
  .hero { padding-top: 48px; }
  .hero-meta { display: none; }
  .principle { padding: 28px 22px; }
  .section { padding-top: 80px; padding-bottom: 80px; }
}

@media (max-width: 480px) {
  .brand-sub { display: none; }
  .hero-title { letter-spacing: -0.02em; }
}

/* ---------- Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
  .reveal { opacity: 1; transform: none; }
  #topology { opacity: 0.45; }
}

/* ---------- Selection ---------- */
::selection {
  background: rgba(109, 179, 255, 0.3);
  color: var(--ink);
}