@import url('https://fonts.googleapis.com/css2?family=Archivo:wght@400;500;600;700&family=Archivo+Narrow:wght@400;500;600;700&display=swap');

/* Design DNA: Split-screen hero — geometric type left, White City apartment interior right; primary red/yellow/blue Bauhaus accents on white; crisp modernist mood */

:root {
  --bt-white: #FFFFFF;
  --bt-graphite: #222222;
  --bt-red: #E03C31;
  --bt-yellow: #F5C400;
  --bt-blue: #1C4B8F;
  --bt-gray: #666666;
  --bt-light: #F4F4F4;
  --bt-border: #E0E0E0;
  --bt-font: 'Archivo', sans-serif;
  --bt-font-narrow: 'Archivo Narrow', sans-serif;
  --bt-max: 1200px;
  --bt-header-h: 72px;
  --bt-transition: 0.25s ease;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--bt-font);
  font-size: 16px;
  line-height: 1.6;
  color: var(--bt-graphite);
  background: var(--bt-white);
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: inherit;
  text-decoration: none;
  transition: color var(--bt-transition);
}

a:hover {
  color: var(--bt-red);
}

ul {
  list-style: none;
}

/* ── Header ── */

.bt-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--bt-header-h);
  background: var(--bt-white);
  border-bottom: 3px solid var(--bt-graphite);
  display: flex;
  align-items: center;
}

.bt-header__inner {
  width: 100%;
  max-width: var(--bt-max);
  margin: 0 auto;
  padding: 0 32px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.bt-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-family: var(--bt-font-narrow);
  font-weight: 700;
  font-size: 1.35rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.bt-logo__mark {
  width: 36px;
  height: 36px;
  background: var(--bt-red);
  position: relative;
  flex-shrink: 0;
}

.bt-logo__mark::after {
  content: '';
  position: absolute;
  bottom: 0;
  right: 0;
  width: 50%;
  height: 50%;
  background: var(--bt-blue);
}

.bt-logo__mark::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 50%;
  height: 50%;
  background: var(--bt-yellow);
}

.bt-logo span {
  display: block;
  font-size: 0.65rem;
  font-weight: 400;
  letter-spacing: 0.2em;
  color: var(--bt-gray);
  margin-top: 2px;
}

.bt-nav {
  display: flex;
  align-items: center;
  gap: 32px;
}

.bt-nav a {
  font-family: var(--bt-font-narrow);
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  position: relative;
}

.bt-nav a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--bt-red);
  transition: width var(--bt-transition);
}

.bt-nav a:hover::after,
.bt-nav a.bt-active::after {
  width: 100%;
}

.bt-nav a.bt-active {
  color: var(--bt-red);
}

.bt-burger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.bt-burger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--bt-graphite);
  transition: var(--bt-transition);
}

.bt-burger.bt-open span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.bt-burger.bt-open span:nth-child(2) {
  opacity: 0;
}

.bt-burger.bt-open span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* ── Hero Split-screen ── */

.bt-hero {
  margin-top: var(--bt-header-h);
  display: grid;
  grid-template-columns: 1fr 1fr;
  min-height: calc(100vh - var(--bt-header-h));
}

.bt-hero__text {
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 64px 48px 64px max(48px, calc((100vw - var(--bt-max)) / 2 + 32px));
  background: var(--bt-white);
}

.bt-hero__label {
  font-family: var(--bt-font-narrow);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.25em;
  text-transform: uppercase;
  color: var(--bt-red);
  margin-bottom: 24px;
}

.bt-hero__title {
  font-family: var(--bt-font-narrow);
  font-size: clamp(2.5rem, 5vw, 4rem);
  font-weight: 700;
  line-height: 1.05;
  letter-spacing: -0.02em;
  text-transform: uppercase;
  margin-bottom: 24px;
}

.bt-hero__title em {
  font-style: normal;
  color: var(--bt-blue);
}

.bt-hero__desc {
  font-size: 1.05rem;
  color: var(--bt-gray);
  max-width: 420px;
  margin-bottom: 40px;
}

.bt-hero__accent-bar {
  display: flex;
  gap: 0;
  margin-bottom: 40px;
}

.bt-hero__accent-bar span {
  display: block;
  height: 4px;
}

.bt-hero__accent-bar span:nth-child(1) { width: 48px; background: var(--bt-red); }
.bt-hero__accent-bar span:nth-child(2) { width: 32px; background: var(--bt-yellow); }
.bt-hero__accent-bar span:nth-child(3) { width: 24px; background: var(--bt-blue); }

.bt-hero__image {
  position: relative;
  overflow: hidden;
}

.bt-hero__image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

/* ── Buttons ── */

.bt-btn {
  display: inline-block;
  font-family: var(--bt-font-narrow);
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  padding: 14px 32px;
  border: 2px solid var(--bt-graphite);
  background: var(--bt-graphite);
  color: var(--bt-white);
  cursor: pointer;
  transition: all var(--bt-transition);
}

.bt-btn:hover {
  background: var(--bt-red);
  border-color: var(--bt-red);
  color: var(--bt-white);
}

.bt-btn--outline {
  background: transparent;
  color: var(--bt-graphite);
}

.bt-btn--outline:hover {
  background: var(--bt-graphite);
  color: var(--bt-white);
}

.bt-btn--red {
  background: var(--bt-red);
  border-color: var(--bt-red);
}

.bt-btn--red:hover {
  background: var(--bt-blue);
  border-color: var(--bt-blue);
}

/* ── Sections ── */

.bt-section {
  padding: 80px 32px;
}

.bt-section--light {
  background: var(--bt-light);
}

.bt-container {
  max-width: var(--bt-max);
  margin: 0 auto;
}

.bt-section__header {
  margin-bottom: 48px;
}

.bt-section__label {
  font-family: var(--bt-font-narrow);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.25em;
  text-transform: uppercase;
  color: var(--bt-red);
  margin-bottom: 12px;
}

.bt-section__title {
  font-family: var(--bt-font-narrow);
  font-size: clamp(1.75rem, 3vw, 2.5rem);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: -0.01em;
}

/* ── Grid layouts ── */

.bt-grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}

.bt-grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.bt-grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

/* ── Cards ── */

.bt-card {
  background: var(--bt-white);
  border: 1px solid var(--bt-border);
  overflow: hidden;
  transition: transform var(--bt-transition), box-shadow var(--bt-transition);
}

.bt-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.08);
}

.bt-card__img {
  aspect-ratio: 4/3;
  overflow: hidden;
}

.bt-card__img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s ease;
}

.bt-card:hover .bt-card__img img {
  transform: scale(1.04);
}

.bt-card__body {
  padding: 24px;
}

.bt-card__tag {
  font-family: var(--bt-font-narrow);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--bt-blue);
  margin-bottom: 8px;
}

.bt-card__title {
  font-family: var(--bt-font-narrow);
  font-size: 1.15rem;
  font-weight: 600;
  text-transform: uppercase;
  margin-bottom: 8px;
}

.bt-card__text {
  font-size: 0.9rem;
  color: var(--bt-gray);
  line-height: 1.5;
}

/* ── Service card ── */

.bt-svc {
  padding: 32px;
  border-left: 4px solid var(--bt-red);
  background: var(--bt-white);
}

.bt-svc:nth-child(2) { border-color: var(--bt-yellow); }
.bt-svc:nth-child(3) { border-color: var(--bt-blue); }

.bt-svc__num {
  font-family: var(--bt-font-narrow);
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--bt-light);
  line-height: 1;
  margin-bottom: 16px;
}

.bt-svc__title {
  font-family: var(--bt-font-narrow);
  font-size: 1.25rem;
  font-weight: 600;
  text-transform: uppercase;
  margin-bottom: 12px;
}

/* ── Stats ── */

.bt-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
  padding: 48px 0;
  border-top: 1px solid var(--bt-border);
  border-bottom: 1px solid var(--bt-border);
}

.bt-stat__num {
  font-family: var(--bt-font-narrow);
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--bt-red);
  line-height: 1;
}

.bt-stat__label {
  font-size: 0.85rem;
  color: var(--bt-gray);
  margin-top: 8px;
}

/* ── CTA Banner ── */

.bt-cta {
  position: relative;
  overflow: hidden;
  min-height: 360px;
  display: flex;
  align-items: center;
}

.bt-cta__bg {
  position: absolute;
  inset: 0;
}

.bt-cta__bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.bt-cta__overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, rgba(34,34,34,0.85) 0%, rgba(34,34,34,0.4) 100%);
}

.bt-cta__content {
  position: relative;
  z-index: 1;
  padding: 64px 32px;
  max-width: var(--bt-max);
  margin: 0 auto;
  width: 100%;
  color: var(--bt-white);
}

.bt-cta__title {
  font-family: var(--bt-font-narrow);
  font-size: clamp(1.75rem, 3vw, 2.5rem);
  font-weight: 700;
  text-transform: uppercase;
  margin-bottom: 16px;
}

.bt-cta__text {
  font-size: 1.05rem;
  opacity: 0.85;
  max-width: 480px;
  margin-bottom: 32px;
}

/* ── Page header ── */

.bt-page-header {
  margin-top: var(--bt-header-h);
  padding: 64px 32px 48px;
  background: var(--bt-light);
  border-bottom: 3px solid var(--bt-graphite);
}

.bt-page-header__inner {
  max-width: var(--bt-max);
  margin: 0 auto;
}

.bt-page-header h1 {
  font-family: var(--bt-font-narrow);
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: -0.01em;
}

.bt-page-header p {
  margin-top: 12px;
  color: var(--bt-gray);
  max-width: 560px;
}

/* ── About values ── */

.bt-values {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.bt-value {
  padding: 32px;
  border-top: 3px solid var(--bt-graphite);
}

.bt-value:nth-child(1) { border-color: var(--bt-red); }
.bt-value:nth-child(2) { border-color: var(--bt-yellow); }
.bt-value:nth-child(3) { border-color: var(--bt-blue); }

.bt-value h3 {
  font-family: var(--bt-font-narrow);
  font-size: 1.1rem;
  font-weight: 600;
  text-transform: uppercase;
  margin-bottom: 12px;
}

/* ── Contact form ── */

.bt-form {
  max-width: 640px;
}

.bt-form__group {
  margin-bottom: 24px;
}

.bt-form label {
  display: block;
  font-family: var(--bt-font-narrow);
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 8px;
}

.bt-form input,
.bt-form textarea,
.bt-form select {
  width: 100%;
  padding: 14px 16px;
  font-family: var(--bt-font);
  font-size: 1rem;
  border: 1px solid var(--bt-border);
  background: var(--bt-white);
  color: var(--bt-graphite);
  transition: border-color var(--bt-transition);
}

.bt-form input:focus,
.bt-form textarea:focus,
.bt-form select:focus {
  outline: none;
  border-color: var(--bt-blue);
}

.bt-form textarea {
  min-height: 140px;
  resize: vertical;
}

.bt-form__row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.bt-contact-info {
  padding: 32px;
  background: var(--bt-graphite);
  color: var(--bt-white);
}

.bt-contact-info h3 {
  font-family: var(--bt-font-narrow);
  font-size: 1.1rem;
  font-weight: 600;
  text-transform: uppercase;
  margin-bottom: 24px;
}

.bt-contact-info p {
  margin-bottom: 16px;
  font-size: 0.95rem;
  opacity: 0.85;
}

.bt-contact-info a {
  color: var(--bt-yellow);
}

.bt-contact-info a:hover {
  color: var(--bt-white);
}

/* ── Privacy ── */

.bt-privacy h2 {
  font-family: var(--bt-font-narrow);
  font-size: 1.35rem;
  font-weight: 600;
  text-transform: uppercase;
  margin: 40px 0 16px;
}

.bt-privacy h2:first-child {
  margin-top: 0;
}

.bt-privacy p,
.bt-privacy li {
  color: var(--bt-gray);
  margin-bottom: 12px;
}

.bt-privacy ul {
  list-style: disc;
  padding-left: 24px;
  margin-bottom: 16px;
}

/* ── Footer ── */

.bt-footer {
  background: var(--bt-graphite);
  color: var(--bt-white);
  padding: 64px 32px 32px;
}

.bt-footer__inner {
  max-width: var(--bt-max);
  margin: 0 auto;
}

.bt-footer__grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
  margin-bottom: 48px;
}

.bt-footer__col h4 {
  font-family: var(--bt-font-narrow);
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  margin-bottom: 20px;
  color: var(--bt-yellow);
}

.bt-footer__col p,
.bt-footer__col a {
  font-size: 0.9rem;
  opacity: 0.8;
  line-height: 1.8;
}

.bt-footer__col a:hover {
  opacity: 1;
  color: var(--bt-yellow);
}

.bt-footer__col ul li {
  margin-bottom: 8px;
}

.bt-footer__logo {
  font-family: var(--bt-font-narrow);
  font-size: 1.2rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 12px;
}

.bt-footer__bottom {
  border-top: 1px solid rgba(255,255,255,0.15);
  padding-top: 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.8rem;
  opacity: 0.6;
}

/* ── Cookie pill ── */

.bt-cookie {
  position: fixed;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 2000;
  background: var(--bt-graphite);
  color: var(--bt-white);
  padding: 16px 28px;
  border-radius: 50px;
  display: flex;
  align-items: center;
  gap: 20px;
  max-width: 90vw;
  box-shadow: 0 8px 32px rgba(0,0,0,0.2);
  font-size: 0.85rem;
}

.bt-cookie p {
  flex: 1;
  line-height: 1.4;
}

.bt-cookie a {
  color: var(--bt-yellow);
  text-decoration: underline;
}

.bt-cookie__btn {
  font-family: var(--bt-font-narrow);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  padding: 8px 20px;
  background: var(--bt-red);
  color: var(--bt-white);
  border: none;
  border-radius: 50px;
  cursor: pointer;
  white-space: nowrap;
  transition: background var(--bt-transition);
}

.bt-cookie__btn:hover {
  background: var(--bt-blue);
}

.bt-cookie.bt-hidden {
  display: none;
}

/* ── Project gallery ── */

.bt-gallery__item {
  position: relative;
  overflow: hidden;
  aspect-ratio: 4/3;
}

.bt-gallery__item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s ease;
}

.bt-gallery__item:hover img {
  transform: scale(1.05);
}

.bt-gallery__caption {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 20px 24px;
  background: linear-gradient(transparent, rgba(34,34,34,0.85));
  color: var(--bt-white);
}

.bt-gallery__caption h3 {
  font-family: var(--bt-font-narrow);
  font-size: 1rem;
  font-weight: 600;
  text-transform: uppercase;
}

.bt-gallery__caption p {
  font-size: 0.8rem;
  opacity: 0.75;
  margin-top: 4px;
}

/* ── Responsive 900px ── */

@media (max-width: 900px) {
  .bt-hero {
    grid-template-columns: 1fr;
    min-height: auto;
  }

  .bt-hero__text {
    padding: 48px 32px;
    order: 1;
  }

  .bt-hero__image {
    order: 0;
    min-height: 50vh;
  }

  .bt-grid-2,
  .bt-grid-3,
  .bt-grid-4,
  .bt-values,
  .bt-stats {
    grid-template-columns: 1fr 1fr;
  }

  .bt-footer__grid {
    grid-template-columns: 1fr 1fr;
  }

  .bt-burger {
    display: flex;
  }

  .bt-nav {
    position: fixed;
    top: var(--bt-header-h);
    left: 0;
    right: 0;
    background: var(--bt-white);
    flex-direction: column;
    padding: 24px 32px;
    gap: 20px;
    border-bottom: 2px solid var(--bt-border);
    transform: translateY(-120%);
    opacity: 0;
    transition: transform var(--bt-transition), opacity var(--bt-transition);
    pointer-events: none;
  }

  .bt-nav.bt-open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }
}

/* ── Responsive 560px ── */

@media (max-width: 560px) {
  .bt-section {
    padding: 56px 20px;
  }

  .bt-hero__text {
    padding: 40px 20px;
  }

  .bt-grid-2,
  .bt-grid-3,
  .bt-grid-4,
  .bt-values,
  .bt-stats,
  .bt-footer__grid {
    grid-template-columns: 1fr;
  }

  .bt-form__row {
    grid-template-columns: 1fr;
  }

  .bt-footer__bottom {
    flex-direction: column;
    gap: 8px;
    text-align: center;
  }

  .bt-cookie {
    flex-direction: column;
    border-radius: 16px;
    text-align: center;
    padding: 20px;
  }

  .bt-page-header {
    padding: 48px 20px 36px;
  }
}