/* =========================================================
   BUILD DIFFERENT STUDIO
   Premium black / silver editorial design system
   ========================================================= */

:root {
  --black: #050505;
  --near-black: #0B0B0B;
  --white: #F5F2EA;
  --pure-white: #FFFFFF;
  --silver: #B8B8B8;
  --muted-silver: #7A7A7A;
  --line: rgba(255, 255, 255, 0.16);
  --line-dark: rgba(0, 0, 0, 0.14);

  --serif: "Cormorant Garamond", Georgia, serif;
  --sans: "Inter", -apple-system, BlinkMacSystemFont, sans-serif;

  --container: 1200px;
  --gutter: clamp(1.25rem, 5vw, 4rem);
  --section-y: clamp(4.5rem, 11vw, 9rem);

  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

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

html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  background: var(--black);
  color: var(--white);
  font-family: var(--sans);
  font-weight: 300;
  line-height: 1.65;
  letter-spacing: 0.01em;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }

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

/* ---------- Layout helpers ---------- */
.container { width: 100%; max-width: var(--container); margin-inline: auto; padding-inline: var(--gutter); }
.narrow { max-width: 760px; }

section { position: relative; }

/* ---------- Typography ---------- */
.eyebrow {
  font-size: 0.72rem;
  letter-spacing: 0.32em;
  text-transform: uppercase;
  color: var(--muted-silver);
  font-weight: 400;
  margin-bottom: 1.4rem;
}

.display {
  font-family: var(--serif);
  font-weight: 500;
  line-height: 1.04;
  letter-spacing: -0.01em;
  font-size: clamp(2rem, 5.2vw, 3.6rem);
}

.section-intro {
  color: var(--silver);
  font-size: 1.05rem;
  margin-top: 1.2rem;
  max-width: 46ch;
}
.section-intro.wide { max-width: 62ch; }

.prose p { color: var(--silver); margin-bottom: 1.15rem; font-size: 1.05rem; }
.prose p:last-child { margin-bottom: 0; }
.prose .lead { color: var(--white); font-family: var(--serif); font-size: 1.5rem; line-height: 1.3; font-style: italic; margin-block: 1.6rem; }

.service-line {
  font-size: 0.78rem;
  letter-spacing: 0.26em;
  text-transform: uppercase;
  color: var(--silver);
  font-weight: 400;
}
.service-line.small { font-size: 0.68rem; color: var(--muted-silver); }

/* =========================================================
   HEADER
   ========================================================= */
.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 100;
  background: transparent;
  border-bottom: 1px solid transparent;
  transition: background 0.5s var(--ease), border-color 0.5s var(--ease), backdrop-filter 0.5s var(--ease);
}
.site-header.scrolled {
  background: rgba(5, 5, 5, 0.82);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 80px;
}

.brand { display: flex; align-items: center; gap: 0.8rem; }
.brand-mark { width: 40px; height: 40px; border-radius: 50%; object-fit: cover; }
.brand-text { display: flex; flex-direction: column; line-height: 1; }
.brand-name { font-family: var(--serif); font-size: 1.18rem; font-weight: 500; letter-spacing: 0.02em; }
.brand-sub { font-size: 0.62rem; letter-spacing: 0.34em; text-transform: uppercase; color: var(--muted-silver); margin-top: 3px; }

.nav { display: flex; gap: 2.4rem; }
.nav a {
  font-size: 0.74rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--silver);
  position: relative;
  padding-bottom: 4px;
  transition: color 0.3s var(--ease);
}
.nav a::after {
  content: "";
  position: absolute;
  left: 0; bottom: 0;
  width: 0; height: 1px;
  background: var(--white);
  transition: width 0.4s var(--ease);
}
.nav a:hover { color: var(--white); }
.nav a:hover::after { width: 100%; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 0.74rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  font-weight: 400;
  padding: 0.95rem 1.9rem;
  border: 1px solid transparent;
  transition: all 0.4s var(--ease);
  cursor: pointer;
  white-space: nowrap;
}
.btn-solid { background: var(--white); color: var(--black); }
.btn-solid:hover { background: var(--pure-white); transform: translateY(-2px); }
.btn-outline { border-color: var(--line); color: var(--white); }
.btn-outline:hover { border-color: var(--silver); background: rgba(255,255,255,0.04); }
.btn-ghost { color: var(--silver); border-color: transparent; padding-inline: 0.6rem; }
.btn-ghost:hover { color: var(--white); }

/* ---------- Mobile nav ---------- */
.nav-toggle { display: none; flex-direction: column; gap: 6px; background: none; border: 0; cursor: pointer; padding: 8px; }
.nav-toggle span { width: 26px; height: 1.5px; background: var(--white); transition: transform 0.35s var(--ease), opacity 0.35s var(--ease); }
.nav-toggle[aria-expanded="true"] span:first-child { transform: translateY(3.75px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:last-child { transform: translateY(-3.75px) rotate(-45deg); }

.mobile-nav[hidden] { display: none; }
.mobile-nav {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
  padding: 1rem var(--gutter) 2.2rem;
  background: rgba(5, 5, 5, 0.96);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
}
.mobile-nav a {
  font-size: 0.82rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--silver);
  padding: 0.85rem 0;
  border-bottom: 1px solid var(--line);
}
.mobile-nav a:last-child { border-bottom: 0; margin-top: 1rem; }

/* =========================================================
   GRID-LINE BACKGROUNDS (architectural)
   ========================================================= */
.grid-lines { position: absolute; inset: 0; overflow: hidden; pointer-events: none; }
.grid-lines svg { width: 100%; height: 100%; }
.grid-lines .gl line, .grid-lines .gl circle {
  fill: none;
  stroke: rgba(255, 255, 255, 0.07);
  stroke-width: 1;
  vector-effect: non-scaling-stroke;
}

/* =========================================================
   HERO
   ========================================================= */
.hero {
  min-height: 100svh;
  display: flex;
  align-items: center;
  padding-top: 80px;
  background: radial-gradient(120% 90% at 50% 0%, #101010 0%, var(--black) 60%);
}
.hero-inner { position: relative; max-width: 900px; padding-block: clamp(3rem, 8vw, 6rem); }

.watermark {
  position: absolute;
  top: -3.5rem;
  right: 0;
  font-family: var(--serif);
  font-size: clamp(9rem, 26vw, 20rem);
  font-weight: 600;
  line-height: 0.8;
  color: rgba(255, 255, 255, 0.025);
  pointer-events: none;
  user-select: none;
  z-index: 0;
}

.hero-title {
  font-family: var(--serif);
  font-weight: 500;
  font-size: clamp(2.8rem, 9vw, 6rem);
  line-height: 0.98;
  letter-spacing: -0.015em;
  position: relative;
  z-index: 1;
}
.hero-title .accent {
  background: linear-gradient(100deg, var(--pure-white) 18%, var(--silver) 55%, var(--muted-silver) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-sub {
  margin-top: 1.8rem;
  max-width: 50ch;
  font-size: clamp(1.02rem, 1.6vw, 1.22rem);
  color: var(--silver);
  font-weight: 300;
  position: relative; z-index: 1;
}

.hero .service-line {
  margin-top: 2.2rem;
  padding-top: 2.2rem;
  border-top: 1px solid var(--line);
  display: inline-block;
  position: relative; z-index: 1;
}

.hero-actions { margin-top: 2.6rem; display: flex; flex-wrap: wrap; gap: 1rem; align-items: center; position: relative; z-index: 1; }

/* =========================================================
   LIGHT SECTIONS (off-white / black text)
   ========================================================= */
.section-light {
  background: var(--white);
  color: var(--near-black);
  padding-block: var(--section-y);
}
.section-light .display,
.section-light .difference-intro h2,
.section-light h3 { color: var(--near-black); }
.section-light .prose p { color: #2a2a2a; }
.section-light .prose .lead { color: var(--near-black); }
.section-light .eyebrow { color: var(--muted-silver); }
.section-light .section-intro { color: #3a3a3a; }

/* ---------- Problem section ---------- */
.problem { position: relative; }
.problem .narrow { position: relative; }
.rule-vertical { position: absolute; left: calc(var(--gutter) - 1px); top: 0.4rem; width: 1px; height: 3.2rem; background: var(--near-black); }
.problem .display { margin-bottom: 2.2rem; padding-left: 2rem; }
.problem .prose { padding-left: 2rem; }

/* =========================================================
   STRATEGY (dark manifesto)
   ========================================================= */
.strategy { padding-block: var(--section-y); background: var(--near-black); overflow: hidden; }
.hairlines {
  position: absolute; inset: 0; pointer-events: none;
  background-image: repeating-linear-gradient(to bottom, transparent 0, transparent 119px, var(--line) 119px, var(--line) 120px);
  opacity: 0.5;
}
.strategy .container { position: relative; }
.strategy .display { margin-bottom: 3rem; }
.strategy-grid { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(2rem, 6vw, 5rem); align-items: start; }

.manifesto p {
  font-family: var(--serif);
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  line-height: 1.12;
  color: var(--muted-silver);
  font-weight: 500;
}
.manifesto .manifesto-final { color: var(--white); margin-top: 0.4rem; }

/* =========================================================
   SERVICES
   ========================================================= */
.services { padding-block: var(--section-y); }
.section-head { margin-bottom: clamp(2.5rem, 6vw, 4rem); }
.section-head .display { margin-top: 0.2rem; }

.card-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.5rem; }
.card {
  border: 1px solid var(--line);
  padding: clamp(1.8rem, 3vw, 2.6rem);
  display: flex;
  flex-direction: column;
  background: linear-gradient(180deg, rgba(255,255,255,0.012), transparent);
  transition: transform 0.5s var(--ease), border-color 0.5s var(--ease), background 0.5s var(--ease);
}
.card:hover {
  transform: translateY(-6px);
  border-color: rgba(255,255,255,0.32);
  background: linear-gradient(180deg, rgba(255,255,255,0.04), transparent);
}
.card-index { font-family: var(--serif); font-size: 1.1rem; color: var(--muted-silver); letter-spacing: 0.1em; }
.card h3 { font-family: var(--serif); font-size: 1.7rem; font-weight: 500; margin: 0.8rem 0 1rem; line-height: 1.1; }
.card > p { color: var(--silver); font-size: 0.98rem; margin-bottom: 1.6rem; }
.card-label { font-size: 0.66rem; letter-spacing: 0.26em; text-transform: uppercase; color: var(--muted-silver); margin-bottom: 0.9rem; }
.card ul { display: flex; flex-direction: column; gap: 0.55rem; margin-bottom: 2rem; }
.card li { font-size: 0.92rem; color: var(--silver); padding-left: 1.1rem; position: relative; }
.card li::before { content: ""; position: absolute; left: 0; top: 0.62em; width: 5px; height: 1px; background: var(--silver); }

.card-cta {
  margin-top: auto;
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--white);
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}
.card-cta span { transition: transform 0.35s var(--ease); display: inline-block; }
.card:hover .card-cta span, .concept:hover .card-cta span { transform: translateX(6px); }

/* =========================================================
   PROCESS / STEPS
   ========================================================= */
.steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 0; counter-reset: none; }
.step { position: relative; padding: 2.2rem 1.8rem 2.2rem 0; }
.step + .step { border-left: 1px solid var(--line-dark); padding-left: 1.8rem; }
.step-num {
  display: block;
  font-family: var(--serif);
  font-size: clamp(3.4rem, 7vw, 5rem);
  font-weight: 500;
  line-height: 1;
  color: rgba(11,11,11,0.16);
  margin-bottom: 0.8rem;
}
.step h3 { font-family: var(--serif); font-size: 1.5rem; font-weight: 500; margin-bottom: 0.6rem; }
.step-body p { color: #3a3a3a; font-size: 0.96rem; }

/* =========================================================
   CONCEPTS
   ========================================================= */
.concepts { padding-block: var(--section-y); background: var(--black); }
.concept-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px; background: var(--line); border: 1px solid var(--line); }
.concept {
  background: var(--black);
  padding: clamp(1.8rem, 3vw, 2.6rem);
  display: flex;
  flex-direction: column;
  min-height: 280px;
  transition: background 0.5s var(--ease);
}
.concept:hover { background: var(--near-black); }
.concept-index { font-family: var(--serif); font-size: 0.95rem; color: var(--muted-silver); letter-spacing: 0.12em; margin-bottom: 1.4rem; }
.concept h3 { font-family: var(--serif); font-size: 1.55rem; font-weight: 500; line-height: 1.12; margin-bottom: 0.9rem; }
.concept p { color: var(--silver); font-size: 0.96rem; margin-bottom: 1.6rem; }
.concept .card-cta { margin-top: auto; }

/* =========================================================
   DIFFERENCE / PRINCIPLES
   ========================================================= */
.difference-layout { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(2.5rem, 7vw, 6rem); align-items: start; }
.difference-intro .display { margin-bottom: 1.8rem; }
.principles { display: grid; grid-template-columns: 1fr 1fr; gap: 1px; background: var(--line-dark); border: 1px solid var(--line-dark); }
.principle { background: var(--white); padding: clamp(1.6rem, 3vw, 2.2rem); }
.principle h3 { font-family: var(--serif); font-size: 1.45rem; font-weight: 500; margin-bottom: 0.6rem; color: var(--near-black); }
.principle p { color: #3a3a3a; font-size: 0.95rem; }

/* =========================================================
   FINAL CTA
   ========================================================= */
.final-cta {
  padding-block: clamp(6rem, 14vw, 11rem);
  background: radial-gradient(120% 100% at 50% 100%, #101010 0%, var(--black) 65%);
  text-align: center;
  overflow: hidden;
}
.cta-inner { position: relative; max-width: 820px; }
.cta-inner .watermark { top: 50%; left: 50%; transform: translate(-50%, -50%); right: auto; }
.cta-inner .hero-title { font-size: clamp(2.6rem, 7.5vw, 5rem); }
.cta-inner .hero-sub { margin-inline: auto; margin-bottom: 2.6rem; }

/* =========================================================
   FOOTER
   ========================================================= */
.site-footer { background: var(--black); border-top: 1px solid var(--line); padding-top: clamp(3rem, 6vw, 4.5rem); }
.footer-inner { display: flex; justify-content: space-between; align-items: flex-start; gap: 2.5rem; flex-wrap: wrap; padding-bottom: 3rem; }
.footer-brand { display: flex; gap: 1rem; align-items: center; }
.footer-brand .brand-mark { width: 44px; height: 44px; border-radius: 50%; }
.footer-name { font-family: var(--serif); font-size: 1.25rem; font-weight: 500; }
.footer-tag { color: var(--muted-silver); font-size: 0.86rem; margin-top: 0.2rem; max-width: 34ch; }
.footer-nav { display: flex; flex-wrap: wrap; gap: 0.4rem 2rem; }
.footer-nav a { font-size: 0.72rem; letter-spacing: 0.16em; text-transform: uppercase; color: var(--silver); transition: color 0.3s var(--ease); }
.footer-nav a:hover { color: var(--white); }
.footer-bottom {
  display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 1rem;
  border-top: 1px solid var(--line);
  padding-block: 1.8rem 2.4rem;
}
.footer-slogan { font-family: var(--serif); font-style: italic; color: var(--silver); font-size: 1.05rem; }

/* =========================================================
   SCROLL REVEAL
   ========================================================= */
.reveal { opacity: 0; transform: translateY(26px); transition: opacity 0.9s var(--ease), transform 0.9s var(--ease); }
.reveal.in { opacity: 1; transform: none; }

/* =========================================================
   RESPONSIVE
   ========================================================= */
@media (max-width: 980px) {
  .difference-layout { grid-template-columns: 1fr; }
  .card-grid { grid-template-columns: 1fr; }
  .concept-grid { grid-template-columns: 1fr 1fr; }
  .steps { grid-template-columns: 1fr 1fr; }
  .step + .step { border-left: 0; padding-left: 0; }
  .steps .step:nth-child(even) { border-left: 1px solid var(--line-dark); padding-left: 1.8rem; }
  .strategy-grid { grid-template-columns: 1fr; gap: 2.5rem; }
}

@media (max-width: 720px) {
  .nav, .nav-cta { display: none; }
  .nav-toggle { display: flex; }
  .concept-grid { grid-template-columns: 1fr; }
  .principles { grid-template-columns: 1fr; }
  .steps { grid-template-columns: 1fr; }
  .steps .step:nth-child(even) { border-left: 0; padding-left: 0; }
  .step { border-top: 1px solid var(--line-dark); }
  .step:first-child { border-top: 0; }
  .footer-bottom { flex-direction: column; align-items: flex-start; }
}

/* ---------- Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  * { animation-duration: 0.001ms !important; transition-duration: 0.001ms !important; }
}