/* =========================================================
   BiI — Ulf-Dirk Stockburger · Portfolio
   Aesthetic: industrial engineering blueprint, dark graphite
   ========================================================= */

:root {
  --bg:        #0b0d11;
  --bg-2:      #11141a;
  --surface:   #14181f;
  --surface-2: #181d26;
  /* halbtransparente Kachel-Flächen — Hintergrund (Zeichnung/Code) scheint durch */
  --glass:     rgba(20, 24, 31, .42);
  --glass-hi:  rgba(26, 32, 42, .62);
  --line:      #232a35;
  --line-soft: #1b212b;
  --ink:       #e8ecf2;
  --ink-dim:   #9aa6b6;
  --ink-faint: #5f6b7b;

  /* dual accents = the two directions */
  --signal:    #4da3ff;   /* PDM → */
  --signal-2:  #38e0c4;   /* glow */
  --amber:     #ff6b5a;   /* ERP ← (Koralle; Variablenname historisch) */

  --mono: "IBM Plex Mono", ui-monospace, monospace;
  --sans: "IBM Plex Sans", system-ui, sans-serif;
  --disp: "Chakra Petch", var(--sans);

  --maxw: 1180px;
  --pad: clamp(20px, 5vw, 80px);
  --ease: cubic-bezier(.2, .7, .2, 1);
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-weight: 300;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

::selection { background: var(--signal); color: #061018; }

a { color: inherit; text-decoration: none; }

/* ===== Backgrounds =====
   Schichtung (hinten→vorne): grid · glow · tech-drawing · code · grain · content */
.bp-grid {
  position: fixed; inset: 0; z-index: -5; pointer-events: none;
  background-image:
    linear-gradient(var(--line-soft) 1px, transparent 1px),
    linear-gradient(90deg, var(--line-soft) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(ellipse 90% 70% at 50% 30%, #000 40%, transparent 90%);
  opacity: .55;
}
.bp-glow {
  position: fixed; z-index: -4; pointer-events: none;
  top: -20%; left: 50%; transform: translateX(-50%);
  width: 1100px; height: 700px;
  background:
    radial-gradient(closest-side, rgba(77,163,255,.12), transparent 70%),
    radial-gradient(closest-side, rgba(56,224,196,.07), transparent 70%);
  background-position: 35% 40%, 70% 30%;
  background-repeat: no-repeat;
  filter: blur(10px);
}

/* Werkzeugbau-Zeichnung — fix LINKS, fadet nach rechts (zur Mitte) aus */
.bg-tech {
  position: fixed; z-index: -3; pointer-events: none;
  top: 50%; left: -3%; transform: translateY(-50%);
  width: min(56vw, 640px); aspect-ratio: 1;
  background: url("../assets/mould.svg") center / contain no-repeat;
  opacity: .55;
  -webkit-mask-image: linear-gradient(90deg, #000 60%, transparent 98%);
          mask-image: linear-gradient(90deg, #000 60%, transparent 98%);
}

/* Sourcecode — fix RECHTS, fadet nach links (zur Mitte) aus → Cross-Fade */
.bg-code {
  position: fixed; z-index: -2; pointer-events: none;
  right: clamp(-12px, 2vw, 40px); top: 86px;
  width: min(48vw, 600px); max-height: 84vh; overflow: hidden;
  margin: 0; white-space: pre; text-align: left;
  font-family: var(--mono); font-size: 12.5px; line-height: 1.75;
  color: var(--signal); opacity: .5;
  -webkit-mask-image: linear-gradient(270deg, #000 60%, transparent 98%);
          mask-image: linear-gradient(270deg, #000 60%, transparent 98%);
}
.grain {
  position: fixed; inset: 0; z-index: -1; pointer-events: none; opacity: .04;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='160' height='160'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='2'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

/* ===== Nav ===== */
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 50;
  display: flex; align-items: center; justify-content: space-between;
  padding: 16px var(--pad);
  background: var(--bg);
  border-bottom: 1px solid var(--line);
}
.brand { display: flex; flex-direction: column; line-height: 1; }
.brand-top { display: flex; align-items: center; gap: 7px; }
.brand-mark {
  display: inline-block; height: 19px; aspect-ratio: 294.8 / 172.8;
  background-color: var(--ink);
  -webkit-mask: url("../assets/bii-wordmark.svg") left center / contain no-repeat;
          mask: url("../assets/bii-wordmark.svg") left center / contain no-repeat;
}
.brand-arrow { color: var(--signal); font-size: 16px; line-height: 1; }
.brand-sub { font-family: var(--mono); font-size: 9.5px; letter-spacing: .28em; text-transform: uppercase; color: var(--ink-faint); margin-top: 5px; }

.nav-links { display: flex; align-items: center; gap: 30px; }
.nav-links a {
  font-family: var(--mono); font-size: 12.5px; letter-spacing: .03em;
  color: var(--ink-dim); transition: color .25s var(--ease); position: relative;
}
.nav-links a .idx { color: var(--signal); opacity: .55; margin-right: 4px; font-size: 10px; }
.nav-links a:hover { color: var(--ink); }
.nav-links a:not(.nav-cta)::after {
  content: ""; position: absolute; left: 0; bottom: -6px; height: 1px; width: 0;
  background: var(--signal); transition: width .3s var(--ease);
}
.nav-links a:not(.nav-cta):hover::after { width: 100%; }
.nav-cta {
  border: 1px solid var(--line); padding: 7px 16px; border-radius: 2px;
  color: var(--ink) !important;
}
.nav-cta:hover { border-color: var(--signal); background: rgba(77,163,255,.08); }
.nav-toggle { display: none; background: none; border: 0; color: var(--ink); font-size: 26px; cursor: pointer; }

/* ===== Hero ===== */
.hero {
  position: relative; min-height: 100vh;
  display: flex; flex-direction: column; justify-content: center;
  padding: 120px var(--pad) 60px;
  max-width: var(--maxw); margin: 0 auto; width: 100%;
}
.hero-tick {
  position: absolute; font-family: var(--mono); color: var(--line);
  font-size: 22px; user-select: none;
}
.hero-tick.tl { top: 96px; left: var(--pad); }
.hero-tick.tr { top: 96px; right: var(--pad); }
.hero-tick.bl { bottom: 40px; left: var(--pad); }
.hero-tick.br { bottom: 40px; right: var(--pad); }

.eyebrow {
  font-family: var(--mono); font-size: 12.5px; letter-spacing: .18em;
  text-transform: uppercase; color: var(--ink-dim);
  display: inline-flex; align-items: center; gap: 12px; margin-bottom: 28px;
}
.eyebrow .dot { width: 7px; height: 7px; border-radius: 50%; background: var(--signal-2); box-shadow: 0 0 12px var(--signal-2); animation: pulse 2.4s infinite; }
@keyframes pulse { 0%,100% { opacity: 1; } 50% { opacity: .35; } }

.hero-title {
  display: flex; align-items: baseline; gap: clamp(8px, 2vw, 24px);
  font-family: var(--disp); font-weight: 700; line-height: .9; margin-top: 6px;
}
/* BiI-Wortmarke = originaler Logo-Schriftzug als SVG (per Maske, themebar) */
.hero-title .wordmark {
  display: block;
  height: clamp(58px, 12.5vw, 150px);
  aspect-ratio: 294.8 / 172.8;
  background-color: var(--ink);
  -webkit-mask: url("../assets/bii-wordmark.svg") left center / contain no-repeat;
          mask: url("../assets/bii-wordmark.svg") left center / contain no-repeat;
}
.hero-mark { font-size: clamp(34px, 7vw, 88px); color: var(--amber); align-self: center; line-height: 1; }
.hero-expand {
  font-family: var(--mono); font-weight: 500;
  font-size: clamp(13px, 1.9vw, 19px); letter-spacing: .34em; text-transform: uppercase;
  color: var(--ink-dim); margin-top: 16px;
}

/* ERP-Hub — ERP im Mittelpunkt, von Quell-Systemen bidirektional bedient */
.hero-hub {
  display: flex; align-items: center; flex-wrap: wrap;
  gap: clamp(8px, 1.6vw, 16px); margin: 32px 0 30px;
}
.hub-side { display: flex; flex-direction: column; gap: 8px; }
.hub-node {
  font-family: var(--mono); font-size: 12.5px; letter-spacing: .03em; white-space: nowrap;
  color: var(--signal); border: 1px solid var(--line); border-radius: 2px;
  padding: 7px 13px; background: var(--glass);
  -webkit-backdrop-filter: blur(3px); backdrop-filter: blur(3px);
}
.hub-link { font-family: var(--mono); font-size: 18px; color: var(--ink-dim); animation: hubpulse 2.4s var(--ease) infinite; }
.hub-core {
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  padding: 14px 26px; border: 1px solid var(--amber); border-radius: 4px;
  background: linear-gradient(180deg, rgba(255,107,90,.14), transparent);
}
.hub-core-name { font-family: var(--disp); font-weight: 700; font-size: clamp(24px, 3.4vw, 34px); letter-spacing: .1em; color: var(--amber); line-height: 1; }
.hub-core-tag { font-family: var(--mono); font-size: 9px; letter-spacing: .22em; text-transform: uppercase; color: var(--ink-faint); margin-top: 6px; }
@keyframes hubpulse { 0%,100% { opacity: .4; } 50% { opacity: 1; } }

.hero-mission {
  font-family: var(--disp); font-weight: 500;
  font-size: clamp(19px, 2.6vw, 27px); line-height: 1.35;
  max-width: 720px; color: var(--ink); margin-bottom: 22px;
  border-left: 2px solid var(--signal); padding-left: 20px;
}
.hero-lede { max-width: 560px; color: var(--ink-dim); font-size: 16px; margin-bottom: 38px; }

.hero-cta { display: flex; gap: 14px; flex-wrap: wrap; }
.btn {
  font-family: var(--mono); font-size: 13px; letter-spacing: .04em;
  padding: 13px 24px; border-radius: 2px; display: inline-flex; align-items: center; gap: 9px;
  transition: all .25s var(--ease); cursor: pointer; border: 1px solid transparent;
}
.btn-primary { background: var(--signal); color: #061018; font-weight: 500; }
.btn-primary:hover { background: #6cb6ff; transform: translateY(-2px); box-shadow: 0 10px 30px rgba(77,163,255,.28); }
.btn-ghost { border-color: var(--line); color: var(--ink-dim); }
.btn-ghost:hover { border-color: var(--ink-dim); color: var(--ink); }

.hero-readout {
  position: absolute; bottom: 40px; right: var(--pad);
  display: flex; gap: 24px; font-family: var(--mono); font-size: 10.5px;
  letter-spacing: .12em; color: var(--ink-faint);
}

/* ===== Sections ===== */
.section { max-width: var(--maxw); margin: 0 auto; padding: 90px var(--pad); width: 100%; }
.section-head { display: flex; align-items: baseline; gap: 18px; margin-bottom: 46px; }
.section-no { font-family: var(--mono); font-size: 13px; color: var(--signal); }
.section-head h2 {
  font-family: var(--disp); font-weight: 600; font-size: clamp(28px, 4.5vw, 44px);
  text-transform: uppercase; letter-spacing: .01em;
}
.section-head .rule { flex: 1; height: 1px; background: linear-gradient(90deg, var(--line), transparent); align-self: center; }
.head-link { font-family: var(--mono); font-size: 12px; color: var(--ink-dim); white-space: nowrap; }
.head-link:hover { color: var(--signal); }
.section-intro { max-width: 640px; color: var(--ink-dim); margin-bottom: 40px; font-size: 17px; }

/* ===== About ===== */
.about-grid { display: grid; grid-template-columns: 1.6fr 1fr; gap: 56px; align-items: start; }
.about-lead p { font-size: 17.5px; color: var(--ink-dim); margin-bottom: 20px; }
.about-lead strong { color: var(--ink); font-weight: 600; }
.about-stats { list-style: none; display: grid; gap: 1px; background: transparent; border: 1px solid var(--line); border-radius: 3px; overflow: hidden; }
.about-stats li { background: var(--glass); -webkit-backdrop-filter: blur(3px); backdrop-filter: blur(3px); padding: 22px 24px; display: flex; flex-direction: column; gap: 4px; }
.stat-n { font-family: var(--disp); font-weight: 700; font-size: 26px; color: var(--signal); letter-spacing: .02em; }
.stat-l { font-family: var(--mono); font-size: 11px; letter-spacing: .14em; text-transform: uppercase; color: var(--ink-faint); }

/* ===== Expertise spec grid ===== */
.spec-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1px; background: transparent; border: 1px solid var(--line); border-radius: 3px; overflow: hidden; }
.spec { background: var(--glass); -webkit-backdrop-filter: blur(3px); backdrop-filter: blur(3px); padding: 26px 24px 30px; transition: background .3s var(--ease); position: relative; }
.spec:hover { background: var(--glass-hi); }
.spec::before { content: ""; position: absolute; left: 0; top: 0; width: 0; height: 2px; background: var(--signal); transition: width .35s var(--ease); }
.spec:hover::before { width: 100%; }
.spec header { display: flex; flex-direction: column; gap: 10px; margin-bottom: 14px; }
.spec-id { font-family: var(--mono); font-size: 11px; color: var(--signal); opacity: .7; letter-spacing: .1em; }
.spec h3 { font-family: var(--disp); font-weight: 600; font-size: 17px; }
.spec .tags { font-family: var(--mono); font-size: 12.5px; color: var(--ink-dim); line-height: 1.7; }

/* ===== Projects ===== */
.project.feature {
  display: block; border: 1px solid var(--line); border-radius: 4px;
  padding: 36px 40px; margin-bottom: 22px;
  background: linear-gradient(135deg, rgba(24,29,38,.55), rgba(20,24,31,.4) 60%);
  -webkit-backdrop-filter: blur(3px); backdrop-filter: blur(3px);
  position: relative; overflow: hidden; transition: border-color .3s var(--ease), transform .3s var(--ease);
}
.project.feature::after {
  content: "⇄"; position: absolute; right: -10px; bottom: -30px;
  font-size: 200px; font-family: var(--disp); color: var(--signal); opacity: .05; pointer-events: none;
}
.project.feature:hover { border-color: var(--signal); transform: translateY(-3px); }
.project-head { display: flex; justify-content: space-between; align-items: center; margin-bottom: 18px; }
.badge { font-family: var(--mono); font-size: 11px; letter-spacing: .12em; color: var(--amber); border: 1px solid rgba(255,178,62,.35); padding: 4px 10px; border-radius: 2px; }
.lang { font-family: var(--mono); font-size: 11.5px; color: var(--ink-faint); letter-spacing: .08em; }
.project.feature h3 { font-family: var(--disp); font-weight: 700; font-size: clamp(26px, 4vw, 38px); margin-bottom: 14px; }
.project.feature h3 .aka { color: var(--ink-faint); font-weight: 500; font-size: .6em; }
.project.feature p { max-width: 640px; color: var(--ink-dim); font-size: 16.5px; margin-bottom: 22px; }

.project-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.project {
  display: flex; flex-direction: column; gap: 12px;
  border: 1px solid var(--line); border-radius: 4px; padding: 26px 24px 22px;
  background: var(--glass); -webkit-backdrop-filter: blur(3px); backdrop-filter: blur(3px);
  transition: all .28s var(--ease); position: relative;
}
.project-grid .project:hover { border-color: var(--signal); transform: translateY(-3px); background: var(--glass-hi); }
.project .lang { align-self: flex-start; }
.project h3 { font-family: var(--disp); font-weight: 600; font-size: 21px; }
.project p { color: var(--ink-dim); font-size: 14.5px; flex: 1; }
.project-go { font-family: var(--mono); font-size: 12.5px; color: var(--signal); display: inline-flex; align-items: center; gap: 7px; }
.project-go .arrow { transition: transform .25s var(--ease); }
.project:hover .project-go .arrow { transform: translateX(5px); }

/* ===== Engineering ===== */
.eng-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.eng {
  display: flex; flex-direction: column;
  border: 1px solid var(--line); border-left: 2px solid var(--signal);
  border-radius: 3px; padding: 30px 30px 28px;
  background: var(--glass); -webkit-backdrop-filter: blur(3px); backdrop-filter: blur(3px);
  transition: background .3s var(--ease), transform .28s var(--ease), border-color .28s var(--ease);
}
.eng:hover { background: var(--glass-hi); transform: translateY(-3px); border-color: var(--signal); }
.eng-tag { font-family: var(--mono); font-size: 11px; letter-spacing: .12em; text-transform: uppercase; color: var(--signal); }
.eng h3 { font-family: var(--disp); font-weight: 700; font-size: 25px; margin: 12px 0 12px; }
.eng p { color: var(--ink-dim); font-size: 15.5px; flex: 1; }
.eng-go { margin-top: 18px; font-family: var(--mono); font-size: 12.5px; color: var(--signal); display: inline-flex; align-items: center; gap: 8px; }
.eng-go .arrow { transition: transform .25s var(--ease); }
.eng:hover .eng-go .arrow { transform: translateX(5px); }

/* ===== Contact ===== */
.contact-inner { text-align: center; padding: 30px 0 10px; }
.contact-claim { font-family: var(--disp); font-weight: 700; font-size: clamp(30px, 6vw, 60px); text-transform: uppercase; line-height: 1; }
.contact-sub { color: var(--ink-dim); max-width: 460px; margin: 20px auto 36px; font-size: 16.5px; }
.contact-links { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }

/* ===== Footer ===== */
.footer {
  max-width: var(--maxw); margin: 0 auto; padding: 30px var(--pad) 50px; width: 100%;
  display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap;
  border-top: 1px solid var(--line);
  font-family: var(--mono); font-size: 11.5px; letter-spacing: .06em; color: var(--ink-faint);
}
.footer .f-brand { color: var(--ink-dim); }

/* ===== Reveal animation =====
   Hidden ONLY when JS is active (html.js), so content stays visible
   if scripting is off or fails. */
.reveal { transition: opacity .7s var(--ease), transform .7s var(--ease); }
.js .reveal { opacity: 0; transform: translateY(22px); }
.hero .reveal { transition-delay: calc(var(--d, 0) * 90ms); }
.js .reveal.in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  .js .reveal { opacity: 1; transform: none; transition: none; }
  .eyebrow .dot, .flow-arrows .ar-r, .flow-arrows .ar-l { animation: none; }
}

/* ===== Responsive ===== */
@media (max-width: 900px) {
  .nav-links { display: none; }
  .nav-toggle { display: block; }
  .nav.open .nav-links {
    display: flex; flex-direction: column; gap: 18px; align-items: flex-start;
    position: absolute; top: 100%; left: 0; right: 0; padding: 24px var(--pad);
    background: var(--bg-2); border-bottom: 1px solid var(--line);
  }
  .about-grid { grid-template-columns: 1fr; gap: 34px; }
  .spec-grid { grid-template-columns: repeat(2, 1fr); }
  .project-grid { grid-template-columns: 1fr 1fr; }
  .eng-grid { grid-template-columns: 1fr; }
  .hero-readout { position: static; margin-top: 40px; flex-wrap: wrap; gap: 14px; }
  .hero-tick { display: none; }
  /* Mobil: BEIDE sichtbar — Zeichnung links, Code rechts, fadend zur Mitte */
  .bg-tech { width: 86vw; left: -10%; opacity: .3;
    -webkit-mask-image: linear-gradient(90deg, #000 55%, transparent 95%);
            mask-image: linear-gradient(90deg, #000 55%, transparent 95%); }
  .bg-code { width: 74vw; right: -8%; font-size: 11px; opacity: .3;
    -webkit-mask-image: linear-gradient(270deg, #000 50%, transparent 92%);
            mask-image: linear-gradient(270deg, #000 50%, transparent 92%); }
}
@media (max-width: 560px) {
  .spec-grid, .project-grid { grid-template-columns: 1fr; }
  .about-stats { grid-template-columns: 1fr 1fr; grid-auto-flow: row; }
  .footer { flex-direction: column; gap: 8px; }
  /* ERP-Hub vertikal: Quellen-Reihe → ⇅ → ERP → ⇅ → Quellen-Reihe */
  .hero-hub { flex-direction: column; align-items: flex-start; gap: 12px; }
  .hub-side { flex-direction: row; flex-wrap: wrap; }
  .hub-link { transform: rotate(90deg); }
}