/* =========================================================
   BERTRAM BAU & INVEST — HIGHEND DESIGN SYSTEM
   Apple-inspired. Editorial. Cinematic.
   ========================================================= */

:root {
  --bg: #fbfbfd;
  --bg-elev: #ffffff;
  --ink: #0a0a0c;
  --ink-2: #1d1d1f;
  --muted: #6e6e73;
  --line: #d2d2d7;
  --accent: #1d1d1f;
  --gold: #b08d57;
  --radius: 22px;
  --radius-lg: 32px;
  --ease: cubic-bezier(.22, 1, .36, 1);
  --ease-smooth: cubic-bezier(.65, .05, .36, 1);
  --container: 1240px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale; }
body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'Helvetica Neue', sans-serif;
  font-weight: 400;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.5;
  letter-spacing: -0.01em;
  overflow-x: hidden;
}
img { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
button { font: inherit; cursor: pointer; border: none; background: none; color: inherit; }

.container { max-width: var(--container); margin: 0 auto; padding: 0 32px; }

/* ===== Reveal animation ===== */
.reveal {
  opacity: 0;
  transform: translateY(36px);
  transition: opacity 1.1s var(--ease), transform 1.1s var(--ease);
}
.reveal.in {
  opacity: 1;
  transform: translateY(0);
}
.reveal:nth-child(2) { transition-delay: .08s; }
.reveal:nth-child(3) { transition-delay: .16s; }
.reveal:nth-child(4) { transition-delay: .24s; }
.reveal:nth-child(5) { transition-delay: .32s; }
.reveal:nth-child(6) { transition-delay: .4s; }

/* =========================================================
   NAV
   ========================================================= */
.nav {
  position: fixed; top: 0; left: 0; right: 0;
  z-index: 100;
  padding: 14px 0;
  background: rgba(251, 251, 253, 0.72);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid rgba(0,0,0,0);
  transition: border-color .3s var(--ease), background .3s var(--ease), padding .3s var(--ease);
}
.nav.scrolled {
  border-bottom-color: rgba(0,0,0,.08);
  padding: 10px 0;
}
.nav-inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 32px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
}
.nav-logo {
  display: flex; align-items: center; gap: 12px;
  font-weight: 600;
  font-size: 14px;
  letter-spacing: -.01em;
}
.logo-mark {
  display: inline-flex;
  width: 34px; height: 34px;
  align-items: center; justify-content: center;
  background: var(--ink);
  color: #fff;
  border-radius: 9px;
  font-weight: 700;
  font-size: 12px;
  letter-spacing: .04em;
}
.logo-mark.big { width: 56px; height: 56px; font-size: 18px; border-radius: 14px; }
.logo-divider { display:none; }
.logo-name { color: var(--ink-2); }

.nav-links {
  list-style: none;
  display: flex;
  gap: 36px;
  margin-left: auto;
  margin-right: 32px;
}
.nav-links a {
  font-size: 13px;
  color: var(--muted);
  font-weight: 500;
  transition: color .25s var(--ease);
}
.nav-links a:hover { color: var(--ink); }

.nav-cta {
  background: var(--ink);
  color: #fff;
  padding: 10px 20px;
  border-radius: 999px;
  font-size: 13px;
  font-weight: 500;
  transition: transform .25s var(--ease), background .25s var(--ease);
}
.nav-cta:hover { transform: translateY(-1px); background: #000; }

.nav-burger { display:none; flex-direction:column; gap:5px; padding:8px; }
.nav-burger span { width:22px; height:1.5px; background: var(--ink); transition: transform .3s var(--ease); }

/* =========================================================
   HERO
   ========================================================= */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  overflow: hidden;
  padding: 140px 32px 80px;
}
.hero-bg {
  position: absolute; inset: 0;
  background:
    radial-gradient(ellipse 80% 60% at 50% 30%, rgba(255,255,255,1) 0%, rgba(255,255,255,0) 70%),
    linear-gradient(180deg, #f3f3f5 0%, #e8e8ec 50%, #d8d9dd 100%);
  z-index: 0;
}
.hero-bg::before {
  content: '';
  position: absolute; inset: 0;
  background:
    radial-gradient(circle at 20% 20%, rgba(176,141,87,.08), transparent 40%),
    radial-gradient(circle at 80% 80%, rgba(29,29,31,.06), transparent 50%);
}
.hero-grain {
  position: absolute; inset: 0;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='2'/%3E%3CfeColorMatrix values='0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 .12 0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  opacity: .5;
  mix-blend-mode: multiply;
  z-index: 1;
  pointer-events: none;
}
.hero-content {
  position: relative;
  z-index: 2;
  max-width: 980px;
}
.hero-eyebrow {
  font-size: 13px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 28px;
  font-weight: 500;
}
.hero-title {
  font-size: clamp(56px, 9vw, 128px);
  font-weight: 600;
  line-height: 1.02;
  letter-spacing: -0.045em;
  color: var(--ink);
  margin-bottom: 32px;
}
.hero-accent {
  background: linear-gradient(180deg, #1d1d1f 0%, #6e6e73 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  font-style: italic;
  font-weight: 500;
}
.hero-sub {
  font-size: clamp(17px, 1.5vw, 22px);
  color: var(--muted);
  max-width: 640px;
  margin: 0 auto 48px;
  font-weight: 400;
  line-height: 1.5;
}
.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 16px 32px;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 500;
  transition: transform .25s var(--ease), background .25s var(--ease), color .25s var(--ease);
  letter-spacing: -.005em;
}
.btn-primary {
  background: var(--ink);
  color: #fff;
}
.btn-primary:hover { transform: translateY(-2px); background: #000; }
.btn-ghost {
  color: var(--ink);
  border: 1px solid var(--line);
  background: rgba(255,255,255,.6);
  backdrop-filter: blur(10px);
}
.btn-ghost:hover { background: #fff; transform: translateY(-2px); }
.btn .arrow { transition: transform .3s var(--ease); }
.btn:hover .arrow { transform: translateX(4px); }
.btn.full { width: 100%; justify-content: center; padding: 18px; margin-top: 8px; }

.hero-scroll {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  z-index: 2;
}
.hero-scroll span {
  font-size: 11px;
  letter-spacing: .25em;
  text-transform: uppercase;
  color: var(--muted);
}
.scroll-line {
  width: 1px;
  height: 48px;
  background: linear-gradient(180deg, var(--ink) 0%, transparent 100%);
  position: relative;
  overflow: hidden;
}
.scroll-line::after {
  content: '';
  position: absolute;
  top: -100%;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(180deg, transparent, var(--ink));
  animation: scrollPulse 2.4s var(--ease) infinite;
}
@keyframes scrollPulse {
  0% { top: -100%; }
  100% { top: 200%; }
}

/* =========================================================
   MARQUEE
   ========================================================= */
.marquee {
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  padding: 32px 0;
  overflow: hidden;
  background: var(--bg);
}
.marquee-track {
  display: flex;
  gap: 48px;
  white-space: nowrap;
  animation: scroll 36s linear infinite;
  font-size: 14px;
  font-weight: 500;
  color: var(--muted);
  letter-spacing: -.005em;
}
.marquee-track span:nth-child(odd) { font-weight: 600; color: var(--ink-2); letter-spacing: -.01em; }
@keyframes scroll {
  to { transform: translateX(-50%); }
}

/* =========================================================
   STATEMENT
   ========================================================= */
.statement {
  padding: 160px 0;
  text-align: center;
}
.statement-eyebrow {
  font-size: 13px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 32px;
  font-weight: 500;
}
.statement-text {
  font-size: clamp(32px, 5vw, 64px);
  font-weight: 600;
  line-height: 1.1;
  letter-spacing: -.035em;
  max-width: 1100px;
  margin: 0 auto;
}
.muted { color: var(--muted); font-weight: 400; }

/* =========================================================
   SECTIONS COMMON
   ========================================================= */
.section-head {
  max-width: 760px;
  margin: 0 auto 80px;
  text-align: center;
}
.eyebrow {
  font-size: 13px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 18px;
  font-weight: 500;
}
.eyebrow.light { color: rgba(255,255,255,.6); }
.section-title {
  font-size: clamp(40px, 5vw, 72px);
  font-weight: 600;
  line-height: 1.05;
  letter-spacing: -.035em;
  margin-bottom: 24px;
}
.section-lead {
  font-size: 19px;
  color: var(--muted);
  line-height: 1.55;
}

/* =========================================================
   SERVICES
   ========================================================= */
.services { padding: 140px 0 160px; }
.service-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}
.service-card {
  background: var(--bg-elev);
  border-radius: var(--radius);
  padding: 48px 36px;
  transition: transform .5s var(--ease), box-shadow .5s var(--ease);
  border: 1px solid var(--line);
  position: relative;
  overflow: hidden;
}
.service-card::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(176,141,87,.04), transparent 60%);
  opacity: 0;
  transition: opacity .5s var(--ease);
}
.service-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 30px 80px -20px rgba(0,0,0,.15);
}
.service-card:hover::before { opacity: 1; }
.service-num {
  font-size: 13px;
  font-weight: 500;
  color: var(--gold);
  letter-spacing: .08em;
  margin-bottom: 32px;
}
.service-card h3 {
  font-size: 24px;
  font-weight: 600;
  letter-spacing: -.02em;
  margin-bottom: 12px;
  position: relative;
}
.service-card p {
  color: var(--muted);
  font-size: 15px;
  line-height: 1.6;
  position: relative;
}

/* =========================================================
   FEATURED PROJECT (Cinematic)
   ========================================================= */
.featured {
  position: relative;
  height: 90vh;
  min-height: 700px;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  color: #fff;
}
.featured-bg {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(180deg, rgba(0,0,0,.55) 0%, rgba(0,0,0,.7) 100%),
    linear-gradient(135deg, #2a2d31 0%, #0a0b0d 100%);
  background-size: cover;
  background-position: center;
  z-index: 0;
}
.featured-bg::after {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 20% 30%, rgba(176,141,87,.18), transparent 50%),
    radial-gradient(circle at 80% 70%, rgba(60,80,120,.2), transparent 50%);
}
.featured-content {
  position: relative;
  z-index: 2;
  text-align: center;
  max-width: 1000px;
  padding: 0 32px;
}
.featured-title {
  font-size: clamp(56px, 9vw, 128px);
  font-weight: 600;
  line-height: 1;
  letter-spacing: -.045em;
  margin-bottom: 24px;
}
.featured-sub {
  font-size: 19px;
  color: rgba(255,255,255,.8);
  margin-bottom: 60px;
  font-weight: 400;
}
.featured-meta {
  display: flex;
  gap: 64px;
  justify-content: center;
  flex-wrap: wrap;
}
.featured-meta div {
  display: flex; flex-direction: column; gap: 6px;
}
.featured-meta span {
  font-size: 11px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: rgba(255,255,255,.5);
}
.featured-meta strong {
  font-size: 24px;
  font-weight: 500;
  letter-spacing: -.01em;
}

/* =========================================================
   PROJECTS GRID
   ========================================================= */
.projects { padding: 160px 0; }
.project-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}
.project-card {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  height: 480px;
  cursor: pointer;
  isolation: isolate;
  background: #1d1d1f;
  transition: transform .6s var(--ease);
}
.project-card.large {
  grid-column: 1 / -1;
  height: 620px;
}
.project-card[data-bg="metro"] { background: linear-gradient(135deg, #3d4f5c 0%, #1a2530 100%); }
.project-card[data-bg="edag"] { background: linear-gradient(135deg, #5a6470 0%, #2a3540 100%); }
.project-card[data-bg="hypo"] { background: linear-gradient(135deg, #8a7355 0%, #2d2620 100%); }
.project-card[data-bg="g12"] { background: linear-gradient(135deg, #4a5a4d 0%, #1f2a23 100%); }
.project-card[data-bg="bs"] { background: linear-gradient(135deg, #6b6e75 0%, #2a2c30 100%); }
.project-card::before {
  content:'';
  position: absolute; inset: 0;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.6' numOctaves='2'/%3E%3CfeColorMatrix values='0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 .15 0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  opacity: .4;
  mix-blend-mode: overlay;
}
.project-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, transparent 40%, rgba(0,0,0,.65) 100%);
  z-index: 1;
  transition: background .5s var(--ease);
}
.project-card:hover { transform: translateY(-4px); }
.project-card:hover .project-overlay {
  background: linear-gradient(180deg, rgba(0,0,0,.2) 0%, rgba(0,0,0,.8) 100%);
}
.project-text {
  position: absolute;
  bottom: 0;
  left: 0; right: 0;
  padding: 40px;
  z-index: 2;
  color: #fff;
}
.project-tag {
  display: inline-block;
  font-size: 11px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: rgba(255,255,255,.7);
  margin-bottom: 16px;
  font-weight: 500;
}
.project-text h3 {
  font-size: clamp(26px, 3vw, 40px);
  font-weight: 600;
  letter-spacing: -.02em;
  margin-bottom: 8px;
  line-height: 1.1;
}
.project-text p {
  font-size: 15px;
  color: rgba(255,255,255,.7);
}

/* =========================================================
   PHILOSOPHY
   ========================================================= */
.philosophy {
  padding: 160px 0;
  background: var(--bg-elev);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.philosophy-grid {
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: 100px;
  align-items: start;
}
.philosophy-text .section-title { margin-bottom: 32px; }
.philosophy-text .lead {
  font-size: 18px;
  color: var(--muted);
  line-height: 1.65;
  margin-bottom: 20px;
  max-width: 540px;
}
.philosophy-pillars {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
}
.pillar {
  border-top: 1px solid var(--line);
  padding-top: 24px;
}
.pillar span {
  font-size: 16px;
  font-weight: 600;
  letter-spacing: -.01em;
  display: block;
  margin-bottom: 12px;
}
.pillar p {
  font-size: 14px;
  color: var(--muted);
  line-height: 1.6;
}

/* =========================================================
   NUMBERS
   ========================================================= */
.numbers {
  padding: 140px 0;
  background: var(--bg);
}
.number-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}
.number {
  text-align: center;
  padding: 32px;
  border-right: 1px solid var(--line);
}
.number:last-child { border-right: none; }
.number strong {
  font-size: clamp(56px, 7vw, 96px);
  font-weight: 600;
  line-height: 1;
  letter-spacing: -.04em;
  display: inline-block;
}
.number sup {
  font-size: clamp(18px, 2vw, 28px);
  font-weight: 500;
  color: var(--muted);
  vertical-align: top;
  margin-left: 4px;
  letter-spacing: -.01em;
}
.number span {
  display: block;
  margin-top: 16px;
  font-size: 13px;
  color: var(--muted);
  letter-spacing: .12em;
  text-transform: uppercase;
  font-weight: 500;
}

/* =========================================================
   CONTACT
   ========================================================= */
.contact {
  padding: 160px 0;
  background: linear-gradient(180deg, #0a0a0c 0%, #18181b 100%);
  color: #fff;
  position: relative;
  overflow: hidden;
}
.contact::before {
  content: '';
  position: absolute; inset: 0;
  background: radial-gradient(circle at 20% 30%, rgba(176,141,87,.1), transparent 50%);
}
.contact-inner {
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: 100px;
  position: relative;
  z-index: 2;
}
.contact-title {
  font-size: clamp(48px, 6vw, 88px);
  font-weight: 600;
  line-height: 1.05;
  letter-spacing: -.04em;
  margin-bottom: 32px;
}
.contact-lead {
  font-size: 19px;
  color: rgba(255,255,255,.7);
  line-height: 1.55;
  max-width: 460px;
  margin-bottom: 64px;
}
.contact-details {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 36px;
}
.contact-details .label {
  display: block;
  font-size: 11px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: rgba(255,255,255,.4);
  margin-bottom: 8px;
  font-weight: 500;
}
.contact-details a, .contact-details p {
  font-size: 16px;
  color: #fff;
  line-height: 1.5;
  transition: color .25s var(--ease);
}
.contact-details a:hover { color: var(--gold); }

/* form */
.contact-form {
  background: rgba(255,255,255,.04);
  border: 1px solid rgba(255,255,255,.1);
  border-radius: var(--radius-lg);
  padding: 40px;
  backdrop-filter: blur(20px);
}
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.contact-form label {
  display: block;
  margin-bottom: 18px;
}
.contact-form span {
  display: block;
  font-size: 11px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: rgba(255,255,255,.5);
  margin-bottom: 10px;
  font-weight: 500;
}
.contact-form input,
.contact-form textarea {
  width: 100%;
  background: rgba(255,255,255,.06);
  border: 1px solid rgba(255,255,255,.12);
  border-radius: 12px;
  padding: 14px 16px;
  color: #fff;
  font: inherit;
  font-size: 15px;
  transition: border-color .25s var(--ease), background .25s var(--ease);
  resize: vertical;
}
.contact-form input:focus,
.contact-form textarea:focus {
  outline: none;
  border-color: rgba(255,255,255,.4);
  background: rgba(255,255,255,.1);
}
.contact-form .btn-primary {
  background: #fff;
  color: var(--ink);
}
.contact-form .btn-primary:hover { background: var(--gold); color: #fff; }

/* =========================================================
   FOOTER
   ========================================================= */
.footer {
  background: #0a0a0c;
  color: rgba(255,255,255,.6);
  padding: 80px 0 32px;
  font-size: 13px;
}
.footer-top {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 60px;
  padding-bottom: 60px;
  border-bottom: 1px solid rgba(255,255,255,.08);
}
.footer-brand { display: flex; flex-direction: column; gap: 20px; }
.footer-brand p { font-size: 14px; color: rgba(255,255,255,.7); line-height: 1.6; }
.footer-cols {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}
.footer-cols h4 {
  font-size: 12px;
  letter-spacing: .15em;
  text-transform: uppercase;
  color: #fff;
  margin-bottom: 18px;
  font-weight: 600;
}
.footer-cols a {
  display: block;
  margin-bottom: 12px;
  color: rgba(255,255,255,.55);
  transition: color .25s var(--ease);
}
.footer-cols a:hover { color: #fff; }
.footer-bottom {
  padding-top: 32px;
  font-size: 12px;
  color: rgba(255,255,255,.4);
  line-height: 1.6;
}

/* =========================================================
   RESPONSIVE
   ========================================================= */
@media (max-width: 1000px) {
  .nav-links { display: none; }
  .nav-burger { display: flex; }
  .service-grid { grid-template-columns: 1fr 1fr; }
  .project-grid { grid-template-columns: 1fr; }
  .project-card.large { grid-column: 1; height: 520px; }
  .philosophy-grid { grid-template-columns: 1fr; gap: 60px; }
  .number-grid { grid-template-columns: 1fr 1fr; gap: 40px 16px; }
  .number { border-right: none; }
  .number:nth-child(odd) { border-right: 1px solid var(--line); }
  .contact-inner { grid-template-columns: 1fr; gap: 60px; }
  .footer-top { grid-template-columns: 1fr; }
}
@media (max-width: 640px) {
  .container, .nav-inner { padding: 0 22px; }
  .nav-cta { display: none; }
  .logo-name { display: none; }
  .hero { padding: 120px 22px 100px; min-height: 90vh; }
  .statement, .services, .projects, .philosophy, .numbers, .contact { padding: 100px 0; }
  .service-grid { grid-template-columns: 1fr; }
  .service-card { padding: 36px 28px; }
  .featured { height: auto; min-height: 600px; padding: 100px 0; }
  .featured-meta { gap: 32px; }
  .philosophy-pillars { grid-template-columns: 1fr; }
  .number-grid { grid-template-columns: 1fr; gap: 24px; }
  .number { border-right: none !important; padding: 24px 0; border-bottom: 1px solid var(--line); }
  .number:last-child { border-bottom: none; }
  .form-row { grid-template-columns: 1fr; }
  .contact-form { padding: 28px; }
  .contact-details { grid-template-columns: 1fr; gap: 28px; }
  .footer-cols { grid-template-columns: 1fr 1fr; }
  .hero-title { letter-spacing: -.035em; }
}