:root {
  --black: #050505;
  --ink: #171717;
  --graphite: #2b2c2c;
  --mist: #d9d8d3;
  --paper: #f6f3ec;
  --white: #ffffff;
  --steel: #b8c1c8;
  --citron: #d7ff64;
  --clay: #b56b4a;
  --line-dark: rgba(255, 255, 255, 0.18);
  --line-light: rgba(5, 5, 5, 0.14);
  --shadow-soft: 0 24px 80px rgba(0, 0, 0, 0.16);
  --radius: 8px;
  --page-pad: 32px;
  --max: 1240px;
  --font-sans: Inter, Pretendard, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: var(--font-sans);
  line-height: 1.55;
  text-rendering: optimizeLegibility;
}

img,
svg {
  display: block;
  max-width: 100%;
}

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

button,
input,
select,
textarea {
  font: inherit;
}

button {
  cursor: pointer;
}

::selection {
  color: var(--black);
  background: var(--citron);
}

.skip-link,
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.skip-link:focus {
  z-index: 100;
  width: auto;
  height: auto;
  margin: 16px;
  padding: 10px 14px;
  color: var(--black);
  background: var(--citron);
  clip: auto;
}

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 50;
  display: flex;
  width: 100%;
  align-items: center;
  justify-content: space-between;
  padding: 20px var(--page-pad);
  color: var(--white);
  transition: background 200ms ease, color 200ms ease, border-color 200ms ease;
}

.site-header.is-scrolled,
.site-header.is-open {
  color: var(--ink);
  background: rgba(246, 243, 236, 0.92);
  border-bottom: 1px solid var(--line-light);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  gap: 12px;
  align-items: center;
  min-height: 42px;
}

.brand-mark {
  display: grid;
  width: 48px;
  height: 42px;
  place-items: center;
  color: var(--black);
  background: var(--white);
  border: 1px solid rgba(255, 255, 255, 0.42);
  border-radius: 2px;
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0;
}

.site-header.is-scrolled .brand-mark,
.site-header.is-open .brand-mark {
  color: var(--white);
  background: var(--black);
  border-color: var(--black);
}

.brand-name {
  font-size: 0.95rem;
  font-weight: 700;
}

.site-nav {
  display: flex;
  gap: 28px;
  align-items: center;
  font-size: 0.9rem;
  font-weight: 600;
}

.site-nav a {
  position: relative;
  padding: 6px 0;
}

.site-nav a::after {
  position: absolute;
  right: 0;
  bottom: 0;
  left: 0;
  height: 1px;
  content: "";
  background: currentColor;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 180ms ease;
}

.site-nav a:hover::after,
.site-nav a:focus-visible::after {
  transform: scaleX(1);
}

.nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  padding: 0;
  color: inherit;
  background: transparent;
  border: 1px solid currentColor;
  border-radius: 999px;
}

.nav-toggle-line {
  display: block;
  width: 16px;
  height: 1px;
  margin: 5px auto;
  background: currentColor;
}

.hero {
  position: relative;
  display: grid;
  min-height: 92svh;
  overflow: hidden;
  color: var(--white);
  background: var(--black);
}

.hero-image,
.hero-overlay {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.hero-image {
  object-fit: cover;
  object-position: center;
}

.hero-overlay {
  background:
    linear-gradient(90deg, rgba(5, 5, 5, 0.92), rgba(5, 5, 5, 0.48) 48%, rgba(5, 5, 5, 0.22)),
    linear-gradient(0deg, rgba(5, 5, 5, 0.88), rgba(5, 5, 5, 0.02) 46%, rgba(5, 5, 5, 0.34));
}

.hero-content {
  position: relative;
  z-index: 1;
  display: flex;
  width: min(100%, var(--max));
  min-height: inherit;
  flex-direction: column;
  justify-content: center;
  margin: 0 auto;
  padding: 116px var(--page-pad) 64px;
}

.eyebrow,
.section-kicker {
  margin: 0 0 18px;
  color: inherit;
  font-size: 0.76rem;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

.hero h1 {
  max-width: 980px;
  margin: 0;
  font-size: 5.6rem;
  line-height: 0.95;
  letter-spacing: 0;
}

.hero-grid {
  display: grid;
  max-width: 960px;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 32px;
  margin-top: 34px;
}

.hero-copy {
  margin: 0;
  color: rgba(255, 255, 255, 0.86);
  font-size: 1.18rem;
  line-height: 1.72;
}

.hero-copy-en {
  color: rgba(255, 255, 255, 0.68);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 32px;
}

.button {
  display: inline-flex;
  min-height: 46px;
  align-items: center;
  justify-content: center;
  padding: 0 20px;
  border: 1px solid currentColor;
  border-radius: 999px;
  font-size: 0.93rem;
  font-weight: 750;
  transition: transform 160ms ease, background 160ms ease, color 160ms ease, border-color 160ms ease;
}

.button:hover,
.button:focus-visible {
  transform: translateY(-2px);
}

.button-light {
  color: var(--black);
  background: var(--white);
  border-color: var(--white);
}

.button-light:hover,
.button-light:focus-visible {
  background: var(--citron);
  border-color: var(--citron);
}

.button-ghost {
  color: var(--white);
  background: rgba(255, 255, 255, 0.08);
}

.button-dark {
  width: 100%;
  color: var(--white);
  background: var(--black);
  border-color: var(--black);
}

.hero-signals {
  display: grid;
  width: min(100%, 760px);
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0;
  padding: 0;
  margin: 68px 0 0;
  list-style: none;
  border-top: 1px solid var(--line-dark);
  border-left: 1px solid var(--line-dark);
}

.hero-signals li {
  min-height: 92px;
  padding: 16px;
  border-right: 1px solid var(--line-dark);
  border-bottom: 1px solid var(--line-dark);
  color: rgba(255, 255, 255, 0.9);
  font-size: 0.92rem;
  font-weight: 700;
}

.hero-signals span {
  display: block;
  margin-bottom: 10px;
  color: var(--steel);
  font-size: 0.72rem;
}

.proof-band {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  color: var(--white);
  background: var(--black);
  border-top: 1px solid var(--line-dark);
}

.proof-band div {
  min-height: 144px;
  padding: 28px var(--page-pad);
  border-right: 1px solid var(--line-dark);
}

.proof-band strong,
.proof-band span {
  display: block;
}

.proof-band strong {
  margin-bottom: 8px;
  font-size: 1.2rem;
}

.proof-band span {
  max-width: 360px;
  color: rgba(255, 255, 255, 0.66);
}

.section {
  padding: 112px var(--page-pad);
}

.section-light {
  color: var(--ink);
  background: var(--paper);
}

.section-dark {
  color: var(--white);
  background: var(--black);
}

.split-layout,
.section-header,
.contact-layout {
  display: grid;
  width: min(100%, var(--max));
  grid-template-columns: minmax(0, 0.95fr) minmax(0, 1.05fr);
  gap: 76px;
  margin: 0 auto;
}

.section-header {
  align-items: end;
  margin-bottom: 52px;
}

.section-header p {
  max-width: 560px;
  margin: 0;
  color: rgba(23, 23, 23, 0.72);
}

.section-dark .section-header p {
  color: rgba(255, 255, 255, 0.64);
}

h2 {
  margin: 0;
  font-size: 3.3rem;
  line-height: 1.04;
  letter-spacing: 0;
}

h3 {
  margin: 0;
  font-size: 1.28rem;
  line-height: 1.22;
  letter-spacing: 0;
}

p {
  font-size: 1rem;
}

.lead {
  margin-top: 0;
  font-size: 1.28rem;
  line-height: 1.66;
}

.body-stack p {
  margin: 0 0 20px;
  color: rgba(23, 23, 23, 0.76);
}

.service-grid {
  display: grid;
  width: min(100%, var(--max));
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  margin: 0 auto;
  background: var(--line-dark);
  border: 1px solid var(--line-dark);
}

.service-card {
  min-height: 420px;
  padding: 28px;
  background: #0d0d0d;
}

.card-index {
  display: inline-block;
  margin-bottom: 56px;
  color: var(--citron);
  font-size: 0.78rem;
  font-weight: 800;
}

.service-card p,
.service-card li {
  color: rgba(255, 255, 255, 0.68);
}

.service-card p {
  margin: 18px 0 28px;
}

.service-card ul {
  padding: 0;
  margin: 0;
  list-style: none;
}

.service-card li {
  padding: 10px 0;
  border-top: 1px solid var(--line-dark);
}

.filter-bar {
  display: flex;
  width: min(100%, var(--max));
  flex-wrap: wrap;
  gap: 8px;
  margin: -20px auto 30px;
}

.filter-button {
  min-height: 38px;
  padding: 0 14px;
  color: var(--ink);
  background: transparent;
  border: 1px solid var(--line-light);
  border-radius: 999px;
  font-size: 0.86rem;
  font-weight: 750;
}

.filter-button.is-active,
.filter-button:hover,
.filter-button:focus-visible {
  color: var(--white);
  background: var(--black);
  border-color: var(--black);
}

.works-grid {
  display: grid;
  width: min(100%, var(--max));
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
  margin: 0 auto;
}

.work-card {
  overflow: hidden;
  background: var(--white);
  border: 1px solid var(--line-light);
  border-radius: var(--radius);
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.06);
  transition: opacity 180ms ease, transform 180ms ease;
}

.work-card.is-hidden {
  display: none;
}

.work-media {
  aspect-ratio: 1 / 0.72;
  border-bottom: 1px solid var(--line-light);
  background:
    linear-gradient(135deg, rgba(215, 255, 100, 0.18), rgba(255, 255, 255, 0) 44%),
    linear-gradient(45deg, #101010, #50545a);
}

.work-media-b {
  background:
    repeating-linear-gradient(90deg, rgba(255, 255, 255, 0.18), rgba(255, 255, 255, 0.18) 1px, transparent 1px, transparent 18px),
    linear-gradient(135deg, #111111, #b8c1c8);
}

.work-media-c {
  background:
    radial-gradient(circle at 26% 28%, rgba(215, 255, 100, 0.6), transparent 18%),
    linear-gradient(135deg, #151515, #b56b4a);
}

.work-media-d {
  background:
    linear-gradient(90deg, rgba(5, 5, 5, 0.8), rgba(5, 5, 5, 0)),
    linear-gradient(135deg, #d9d8d3, #5d666b);
}

.work-content {
  min-height: 206px;
  padding: 22px;
}

.work-content span {
  display: inline-block;
  margin-bottom: 18px;
  color: rgba(23, 23, 23, 0.62);
  font-size: 0.74rem;
  font-weight: 800;
  text-transform: uppercase;
}

.work-content p {
  margin: 16px 0 0;
  color: rgba(23, 23, 23, 0.7);
  font-size: 0.94rem;
}

.statement-band {
  padding: 112px var(--page-pad);
  color: var(--white);
  background:
    linear-gradient(90deg, rgba(5, 5, 5, 0.96), rgba(5, 5, 5, 0.72)),
    url("../img/bzxb-brand-visual.png") center / cover;
}

.statement-band h2,
.statement-band p {
  width: min(100%, var(--max));
  margin-right: auto;
  margin-left: auto;
}

.statement-band h2 {
  max-width: 940px;
  font-size: 4.2rem;
}

.statement-band p:not(.section-kicker) {
  max-width: 720px;
  margin-top: 28px;
  margin-bottom: 0;
  color: rgba(255, 255, 255, 0.72);
  font-size: 1.2rem;
}

.clients-section .section-header {
  margin-bottom: 34px;
}

.logo-wall {
  display: grid;
  width: min(100%, var(--max));
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  margin: 0 auto;
  background: var(--line-light);
  border: 1px solid var(--line-light);
}

.logo-wall span {
  display: grid;
  min-height: 76px;
  place-items: center;
  padding: 16px;
  background: rgba(255, 255, 255, 0.5);
  color: rgba(23, 23, 23, 0.7);
  font-size: 0.95rem;
  font-weight: 750;
  text-align: center;
}

.program-list {
  display: grid;
  gap: 1px;
  background: var(--line-dark);
  border: 1px solid var(--line-dark);
}

.program-item {
  padding: 28px;
  background: #0d0d0d;
}

.program-item span {
  display: block;
  margin-bottom: 16px;
  color: var(--citron);
  font-size: 1.1rem;
  font-weight: 800;
}

.program-item p {
  margin: 0;
  color: rgba(255, 255, 255, 0.72);
}

.contact-layout {
  align-items: start;
}

.contact-email {
  margin-top: 28px;
}

.contact-email a {
  display: inline-flex;
  min-height: 42px;
  align-items: center;
  padding: 0 16px;
  color: var(--ink);
  border: 1px solid var(--line-light);
  border-radius: 999px;
  font-weight: 800;
}

.contact-email a:hover,
.contact-email a:focus-visible {
  background: var(--citron);
  border-color: var(--citron);
}

.contact-form {
  display: grid;
  gap: 16px;
  padding: 28px;
  background: var(--white);
  border: 1px solid var(--line-light);
  border-radius: var(--radius);
  box-shadow: var(--shadow-soft);
}

.contact-form label {
  display: grid;
  gap: 8px;
}

.contact-form span {
  font-size: 0.82rem;
  font-weight: 800;
}

.contact-form input,
.contact-form select,
.contact-form textarea {
  width: 100%;
  padding: 13px 14px;
  color: var(--ink);
  background: #fbfaf6;
  border: 1px solid var(--line-light);
  border-radius: 6px;
  outline: none;
}

.contact-form input:focus,
.contact-form select:focus,
.contact-form textarea:focus {
  border-color: var(--black);
  box-shadow: 0 0 0 3px rgba(215, 255, 100, 0.55);
}

.form-status {
  min-height: 24px;
  margin: 0;
  color: rgba(23, 23, 23, 0.7);
  font-size: 0.9rem;
}

.site-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 30px var(--page-pad);
  color: rgba(255, 255, 255, 0.72);
  background: var(--black);
  border-top: 1px solid var(--line-dark);
}

.site-footer strong,
.site-footer span {
  display: block;
}

.site-footer strong {
  color: var(--white);
}

.site-footer a {
  font-size: 0.9rem;
  font-weight: 800;
}

.reveal {
  opacity: 0;
  transform: translateY(16px);
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
  transition: opacity 520ms ease, transform 520ms ease;
}

:focus-visible {
  outline: 2px solid var(--citron);
  outline-offset: 3px;
}

@media (max-width: 1100px) {
  :root {
    --page-pad: 24px;
  }

  .hero h1 {
    font-size: 4.35rem;
  }

  h2 {
    font-size: 2.65rem;
  }

  .split-layout,
  .section-header,
  .contact-layout {
    grid-template-columns: 1fr;
    gap: 34px;
  }

  .service-grid,
  .works-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .service-card {
    min-height: 340px;
  }

  .logo-wall {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (max-width: 760px) {
  :root {
    --page-pad: 18px;
  }

  .site-header {
    padding-top: 14px;
    padding-bottom: 14px;
  }

  .brand-name {
    display: none;
  }

  .nav-toggle {
    display: block;
  }

  .site-nav {
    position: fixed;
    top: 70px;
    right: 18px;
    left: 18px;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 8px;
    color: var(--ink);
    background: rgba(246, 243, 236, 0.98);
    border: 1px solid var(--line-light);
    border-radius: var(--radius);
    box-shadow: var(--shadow-soft);
  }

  .site-nav.is-open {
    display: flex;
  }

  .site-nav a {
    padding: 14px 12px;
  }

  .hero {
    min-height: 92svh;
  }

  .hero-content {
    padding-top: 104px;
    padding-bottom: 42px;
  }

  .hero-overlay {
    background:
      linear-gradient(90deg, rgba(5, 5, 5, 0.94), rgba(5, 5, 5, 0.62)),
      linear-gradient(0deg, rgba(5, 5, 5, 0.88), rgba(5, 5, 5, 0.14));
  }

  .hero h1 {
    font-size: 3.05rem;
    line-height: 1;
  }

  .hero-grid {
    grid-template-columns: 1fr;
    gap: 14px;
    margin-top: 24px;
  }

  .hero-copy {
    font-size: 1rem;
  }

  .hero-signals {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    margin-top: 38px;
  }

  .hero-signals li {
    min-height: 80px;
    padding: 12px;
    font-size: 0.82rem;
  }

  .proof-band {
    grid-template-columns: 1fr;
  }

  .proof-band div {
    min-height: 112px;
    border-right: 0;
    border-bottom: 1px solid var(--line-dark);
  }

  .section,
  .statement-band {
    padding-top: 78px;
    padding-bottom: 78px;
  }

  h2,
  .statement-band h2 {
    font-size: 2.28rem;
  }

  .lead {
    font-size: 1.08rem;
  }

  .service-grid,
  .works-grid,
  .logo-wall {
    grid-template-columns: 1fr;
  }

  .service-card {
    min-height: auto;
  }

  .card-index {
    margin-bottom: 42px;
  }

  .work-content {
    min-height: auto;
  }

  .contact-form {
    padding: 20px;
  }

  .site-footer {
    flex-direction: column;
    align-items: flex-start;
    gap: 18px;
  }
}

@media (max-width: 420px) {
  .hero h1 {
    font-size: 2.55rem;
  }

  .hero-signals {
    grid-template-columns: 1fr;
  }

  .button {
    width: 100%;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.001ms !important;
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
  }

  .reveal {
    opacity: 1;
    transform: none;
  }
}