/* =========================================================
   CHAT'STUDIO — Xưởng thiết kế nội thất — Interior Design
   Design system dùng chung cho toàn bộ website
   ========================================================= */

:root {
  --color-bg: #faf8f4;
  --color-bg-alt: #f2ede4;
  --color-surface: #ffffff;
  --color-ink: #2b2620;
  --color-ink-soft: #5c5548;
  --color-line: #e4dcce;
  --color-wood: #7c5c3e;
  --color-wood-dark: #4a3826;
  --color-terracotta: #b5652d;
  --color-terracotta-dark: #9a5323;
  --color-sage: #6f7a5e;

  --font-display: "Fraunces", "Times New Roman", serif;
  --font-body: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;

  --container: 1200px;
  --radius: 4px;
  --shadow-soft: 0 10px 40px -12px rgba(43, 38, 32, 0.18);
  --transition: 0.35s cubic-bezier(0.22, 1, 0.36, 1);
}

* { box-sizing: border-box; min-width: 0; }
html { scroll-behavior: smooth; }
body { overflow-x: hidden; }

body {
  margin: 0;
  background: var(--color-bg);
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

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

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

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.15;
  margin: 0 0 0.5em;
  letter-spacing: -0.01em;
  overflow-wrap: break-word;
}

h1 { font-size: clamp(2.4rem, 5vw, 4rem); font-weight: 500; }
h2 { font-size: clamp(1.9rem, 3.2vw, 2.6rem); }
h3 { font-size: 1.3rem; }

p { margin: 0 0 1em; color: var(--color-ink-soft); overflow-wrap: break-word; }

.container {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 28px;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 0.78rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--color-terracotta);
  font-weight: 600;
  margin-bottom: 14px;
}
.eyebrow::before {
  content: "";
  width: 26px;
  height: 1px;
  background: var(--color-terracotta);
  display: inline-block;
}

.section { padding: 100px 0; }
.section-tight { padding: 64px 0; }
.section-alt { background: var(--color-bg-alt); }
.section-dark {
  background: var(--color-ink);
  color: #f2ede4;
}
.section-dark p { color: #cfc7b8; }
.section-dark h2, .section-dark h3 { color: #faf8f4; }

.section-head {
  max-width: 640px;
  margin-bottom: 56px;
}
.section-head.center {
  margin-left: auto;
  margin-right: auto;
  text-align: center;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 15px 30px;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 0.92rem;
  letter-spacing: 0.02em;
  text-align: center;
  border: 1px solid transparent;
  cursor: pointer;
  transition: all var(--transition);
  max-width: 100%;
}
.btn-primary {
  background: var(--color-terracotta);
  color: #fff;
}
.btn-primary:hover { background: var(--color-terracotta-dark); transform: translateY(-2px); }
.btn-outline {
  background: transparent;
  border-color: currentColor;
  color: var(--color-ink);
}
.btn-outline:hover { background: var(--color-ink); color: #fff; border-color: var(--color-ink); }
.btn-light {
  background: #fff;
  color: var(--color-ink);
}
.btn-light:hover { background: var(--color-terracotta); color: #fff; transform: translateY(-2px); }
.btn-ghost-light {
  border-color: rgba(255,255,255,0.6);
  color: #fff;
}
.btn-ghost-light:hover { background: #fff; color: var(--color-ink); }

/* ---------- Header ---------- */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  padding: 22px 0;
  transition: all var(--transition);
}
.site-header.is-scrolled,
.site-header.is-solid {
  padding: 14px 0;
  background: rgba(250, 248, 244, 0.92);
  backdrop-filter: blur(10px);
  box-shadow: 0 1px 0 var(--color-line);
}
.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand {
  font-family: var(--font-display);
  font-size: 1.4rem;
  font-weight: 600;
  color: var(--color-ink);
  display: flex;
  align-items: center;
  gap: 12px;
  line-height: 1.1;
}
.brand-logo {
  height: 46px;
  width: auto;
  flex-shrink: 0;
  transition: height var(--transition);
}
.brand-text { display: flex; flex-direction: column; flex-shrink: 0; overflow-wrap: break-word; }
.site-header.is-scrolled .brand-logo,
.site-footer .brand-logo { height: 40px; }
.site-header.is-transparent:not(.is-scrolled) .brand,
.site-header.is-transparent:not(.is-scrolled) .main-nav a,
.site-header.is-transparent:not(.is-scrolled) .nav-toggle span {
  color: #fff;
}
.brand small {
  font-family: var(--font-body);
  font-size: 0.6rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--color-terracotta);
  font-weight: 600;
}
.footer-brand .brand-logo { height: 52px; }

.main-nav { display: flex; align-items: center; gap: 38px; }
.main-nav a {
  font-size: 0.92rem;
  font-weight: 500;
  position: relative;
  padding: 4px 0;
}
.main-nav a::after {
  content: "";
  position: absolute;
  left: 0; bottom: -2px;
  width: 0; height: 1.5px;
  background: currentColor;
  transition: width var(--transition);
}
.main-nav a:hover::after,
.main-nav a.active::after { width: 100%; }
.main-nav a.active { color: var(--color-terracotta); }

.header-cta { display: flex; align-items: center; gap: 20px; }
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
}
.nav-toggle span {
  width: 24px; height: 2px;
  background: var(--color-ink);
  transition: var(--transition);
}

/* ---------- Hero (inner pages) ---------- */
.page-hero {
  position: relative;
  min-height: 56vh;
  display: flex;
  align-items: flex-end;
  color: #fff;
  background-size: cover;
  background-position: center;
  padding-top: 140px;
}
.page-hero::before {
  content: "";
  position: absolute; inset: 0;
  background: linear-gradient(180deg, rgba(20,17,12,0.35) 0%, rgba(20,17,12,0.72) 100%);
}
.page-hero .container { position: relative; padding-bottom: 64px; }
.page-hero .eyebrow { color: #e9c9a6; }
.page-hero .eyebrow::before { background: #e9c9a6; }
.page-hero p.lead {
  max-width: 560px;
  color: #ece5d8;
  font-size: 1.05rem;
}

/* ---------- Home Hero ---------- */
.hero-home {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  background-size: cover;
  background-position: center;
  color: #fff;
  overflow: hidden;
}
.hero-home::before {
  content: "";
  position: absolute; inset: 0;
  background: linear-gradient(180deg, rgba(15,13,10,0.35) 0%, rgba(15,13,10,0.55) 55%, rgba(15,13,10,0.85) 100%);
}
.hero-home .container { position: relative; padding-top: 120px; padding-bottom: 90px; }
.hero-home .eyebrow { color: #e9c9a6; }
.hero-home .eyebrow::before { background: #e9c9a6; }
.hero-home h1 { max-width: 780px; color: #fff; }
.hero-home p.lead {
  max-width: 520px;
  font-size: 1.08rem;
  color: #ece5d8;
}
.hero-actions { display: flex; gap: 16px; margin-top: 34px; flex-wrap: wrap; }

.hero-scroll {
  position: absolute;
  bottom: 34px; left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: #ece5d8;
}
.hero-scroll .line {
  width: 1px; height: 40px;
  background: rgba(255,255,255,0.5);
  overflow: hidden;
  position: relative;
}
.hero-scroll .line::after {
  content: "";
  position: absolute; top: -100%; left: 0;
  width: 100%; height: 100%;
  background: #fff;
  animation: scrollLine 1.8s infinite;
}
@keyframes scrollLine { to { top: 100%; } }

/* ---------- Stat strip ---------- */
.stat-strip {
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-line);
}
.stat-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  padding: 44px 0;
}
.stat-item { text-align: center; padding: 0 12px; border-left: 1px solid var(--color-line); }
.stat-item:first-child { border-left: none; }
.stat-num {
  font-family: var(--font-display);
  font-size: 2.1rem;
  color: var(--color-terracotta);
  display: block;
}
.stat-label { font-size: 0.85rem; color: var(--color-ink-soft); }

/* ---------- Split / feature blocks ---------- */
.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
}
.split.reverse .split-media { order: 2; }
.split.reverse .split-copy { order: 1; }
.split-media { position: relative; }
.split-media img { border-radius: var(--radius); }
.split-media .frame {
  position: absolute;
  inset: 18px -18px -18px 18px;
  border: 1.5px solid var(--color-terracotta);
  z-index: -1;
  border-radius: var(--radius);
}
.split-copy .tag-list { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 24px; }
.tag-list li {
  list-style: none;
  font-size: 0.85rem;
  background: var(--color-bg-alt);
  padding: 8px 16px;
  border-radius: 30px;
  color: var(--color-ink-soft);
}

/* ---------- Cards ---------- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 26px;
}
.service-card {
  background: var(--color-surface);
  border: 1px solid var(--color-line);
  border-radius: var(--radius);
  padding: 36px 28px;
  transition: all var(--transition);
}
.service-card:hover {
  border-color: var(--color-terracotta);
  transform: translateY(-6px);
  box-shadow: var(--shadow-soft);
}
.service-card .num {
  font-family: var(--font-display);
  font-size: 0.85rem;
  color: var(--color-terracotta);
  letter-spacing: 0.1em;
}
.service-card h3 { margin-top: 14px; }
.service-card p { font-size: 0.94rem; margin-bottom: 18px; }
.service-card .card-link {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--color-ink);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}
.service-card .card-link svg { transition: transform var(--transition); }
.service-card:hover .card-link svg { transform: translateX(4px); }

/* ---------- Process steps ---------- */
.process-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 30px;
  counter-reset: step;
}
.process-step { position: relative; padding-top: 20px; }
.process-step::before {
  counter-increment: step;
  content: "0" counter(step);
  font-family: var(--font-display);
  font-size: 2.6rem;
  color: var(--color-line);
  display: block;
  margin-bottom: 10px;
}
.process-step h3 { font-size: 1.1rem; }
.process-step p { font-size: 0.92rem; }
.process-grid .process-step:not(:last-child)::after {
  content: "";
  position: absolute;
  top: 30px; right: -18px;
  width: 12px; height: 1px;
  background: var(--color-line);
  display: none;
}
@media (min-width: 900px) {
  .process-grid .process-step:not(:last-child)::after { display: block; }
}

/* ---------- Gallery ---------- */
.gallery-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}
.gallery-grid.dense .g-item:nth-child(3n+1) { grid-row: span 2; }
.g-item {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius);
  cursor: pointer;
  background: var(--color-bg-alt);
}
.g-item img {
  width: 100%; height: 100%;
  object-fit: cover;
  transition: transform 0.6s ease;
}
.g-item:hover img { transform: scale(1.06); }
.g-item .g-cap {
  position: absolute; inset: auto 0 0 0;
  padding: 18px 20px;
  background: linear-gradient(0deg, rgba(20,17,12,0.82), transparent);
  color: #fff;
  opacity: 0;
  transform: translateY(8px);
  transition: all var(--transition);
}
.g-item:hover .g-cap { opacity: 1; transform: translateY(0); }
.g-cap .g-tag {
  font-size: 0.68rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: #e9c9a6;
  display: block;
  margin-bottom: 3px;
}
.g-cap .g-title { font-family: var(--font-display); font-size: 1.05rem; }

/* filter tabs */
.filter-bar {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 40px;
}
.filter-btn {
  padding: 10px 20px;
  border-radius: 30px;
  border: 1px solid var(--color-line);
  background: transparent;
  font-size: 0.86rem;
  font-weight: 500;
  cursor: pointer;
  color: var(--color-ink-soft);
  transition: all var(--transition);
}
.filter-btn:hover { border-color: var(--color-terracotta); color: var(--color-ink); }
.filter-btn.active { background: var(--color-ink); border-color: var(--color-ink); color: #fff; }
.g-item.is-hidden { display: none; }

/* ---------- Decor detail cards ---------- */
.decor-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 30px;
}
.decor-card {
  background: var(--color-surface);
  border: 1px solid var(--color-line);
  border-radius: var(--radius);
  overflow: hidden;
  transition: all var(--transition);
}
.decor-card:hover { box-shadow: var(--shadow-soft); transform: translateY(-6px); }
.decor-card .thumb { aspect-ratio: 4/5; overflow: hidden; cursor: pointer; }
.decor-card .thumb img { width: 100%; height: 100%; object-fit: cover; transition: transform 0.6s ease; }
.decor-card:hover .thumb img { transform: scale(1.05); }
.decor-body { padding: 22px 24px 26px; }
.decor-body .g-tag {
  font-size: 0.7rem; letter-spacing: 0.12em; text-transform: uppercase;
  color: var(--color-terracotta); font-weight: 600;
}
.decor-body h3 { margin: 8px 0 6px; }
.decor-body p { font-size: 0.9rem; margin-bottom: 0; }

/* ---------- Values ---------- */
.value-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 30px;
}
.value-item { text-align: left; }
.value-icon {
  width: 52px; height: 52px;
  border-radius: 50%;
  background: var(--color-bg-alt);
  display: flex; align-items: center; justify-content: center;
  color: var(--color-terracotta);
  margin-bottom: 18px;
}

/* ---------- Testimonial ---------- */
.quote-block {
  max-width: 760px;
  margin: 0 auto;
  text-align: center;
}
.quote-block blockquote {
  font-family: var(--font-display);
  font-size: clamp(1.3rem, 2.4vw, 1.9rem);
  font-weight: 400;
  line-height: 1.5;
  margin: 0 0 26px;
  color: #fff;
}
.quote-cite { font-size: 0.9rem; color: #e9c9a6; }

/* ---------- CTA banner ---------- */
.cta-banner {
  background: var(--color-terracotta);
  color: #fff;
  border-radius: var(--radius);
  padding: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 40px;
  flex-wrap: wrap;
}
.cta-banner h2 { color: #fff; margin-bottom: 8px; }
.cta-banner p { color: #fbe6d3; margin: 0; }

/* ---------- Contact ---------- */
.contact-grid {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 60px;
}
.info-card {
  display: flex;
  gap: 18px;
  padding: 22px 0;
  border-bottom: 1px solid var(--color-line);
}
.info-card:first-child { padding-top: 0; }
.info-icon {
  width: 44px; height: 44px;
  border-radius: 50%;
  background: var(--color-bg-alt);
  color: var(--color-terracotta);
  display: flex; align-items: center; justify-content: center;
  flex-shrink: 0;
}
.info-card h4 { margin: 0 0 4px; font-family: var(--font-body); font-size: 0.95rem; font-weight: 700; }
.info-card p { margin: 0; font-size: 0.92rem; }
.social-row { display: flex; gap: 12px; margin-top: 28px; }
.social-row a {
  width: 42px; height: 42px;
  border-radius: 50%;
  border: 1px solid var(--color-line);
  display: flex; align-items: center; justify-content: center;
  transition: all var(--transition);
}
.social-row a:hover { background: var(--color-terracotta); border-color: var(--color-terracotta); color: #fff; }

.form-card {
  background: var(--color-surface);
  border: 1px solid var(--color-line);
  border-radius: var(--radius);
  padding: 40px;
}
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.field { margin-bottom: 20px; }
.field label {
  display: block;
  font-size: 0.82rem;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--color-ink);
}
.field input, .field select, .field textarea {
  width: 100%;
  padding: 13px 16px;
  border: 1px solid var(--color-line);
  border-radius: var(--radius);
  font-family: var(--font-body);
  font-size: 0.94rem;
  background: var(--color-bg);
  color: var(--color-ink);
  transition: border-color var(--transition);
}
.field input:focus, .field select:focus, .field textarea:focus {
  outline: none;
  border-color: var(--color-terracotta);
}
.field textarea { resize: vertical; min-height: 120px; }
.form-note { font-size: 0.8rem; color: var(--color-ink-soft); margin-top: 14px; }

.map-block {
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--color-line);
  height: 360px;
}
.map-block iframe { width: 100%; height: 100%; border: 0; filter: grayscale(30%); }

/* ---------- Footer ---------- */
.site-footer {
  background: var(--color-ink);
  color: #cfc7b8;
  padding: 76px 0 28px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 0.8fr 0.8fr 1fr;
  gap: 50px;
  padding-bottom: 50px;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}
.footer-brand .brand { color: #fff; }
.footer-brand p { font-size: 0.9rem; max-width: 280px; margin-top: 16px; }
.footer-col h4 {
  color: #fff; font-family: var(--font-body); font-size: 0.85rem;
  text-transform: uppercase; letter-spacing: 0.08em; margin-bottom: 20px;
}
.footer-col ul { list-style: none; padding: 0; margin: 0; display: flex; flex-direction: column; gap: 12px; }
.footer-col a { font-size: 0.9rem; color: #cfc7b8; transition: color var(--transition); }
.footer-col a:hover { color: #e9c9a6; }
.footer-bottom {
  display: flex; justify-content: space-between; align-items: center;
  padding-top: 24px; font-size: 0.82rem; color: #8f8878; flex-wrap: wrap; gap: 10px;
}

/* ---------- Lightbox ---------- */
.lightbox {
  position: fixed; inset: 0;
  background: rgba(15,13,10,0.94);
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  padding: 40px;
}
.lightbox.is-open { display: flex; }
.lightbox img { max-width: 90vw; max-height: 85vh; border-radius: 2px; }
.lightbox-close {
  position: absolute; top: 28px; right: 32px;
  background: none; border: none; color: #fff;
  font-size: 1.8rem; cursor: pointer; line-height: 1;
}
.lightbox-caption {
  position: absolute; bottom: 30px; left: 50%; transform: translateX(-50%);
  color: #e9c9a6; font-size: 0.85rem; letter-spacing: 0.05em;
}

/* ---------- Reveal on scroll ---------- */
.reveal { opacity: 0; transform: translateY(24px); transition: all 0.8s cubic-bezier(0.22,1,0.36,1); }
.reveal.is-visible { opacity: 1; transform: translateY(0); }

/* =========================================================
   Responsive
   ========================================================= */
@media (max-width: 1180px) {
  .main-nav { gap: 22px; }
  .brand-text small { display: none; }
}

@media (max-width: 1024px) {
  .main-nav, .header-cta .btn { display: none; }
  .nav-toggle { display: flex; }
  .card-grid, .process-grid, .decor-grid { grid-template-columns: repeat(2, 1fr); }
  .value-grid { grid-template-columns: repeat(2, 1fr); }
  .split { grid-template-columns: 1fr; gap: 40px; }
  .split.reverse .split-media, .split.reverse .split-copy { order: initial; }
  .contact-grid { grid-template-columns: 1fr; }
  .stat-grid { grid-template-columns: repeat(2, 1fr); }
  .stat-item:nth-child(3) { border-left: none; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 760px) {
  .card-grid, .process-grid, .decor-grid, .gallery-grid { grid-template-columns: 1fr 1fr; }
  .gallery-grid.dense .g-item:nth-child(3n+1) { grid-row: auto; }
  .value-grid { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .cta-banner { padding: 40px 28px; flex-direction: column; align-items: flex-start; }
  .footer-grid { grid-template-columns: 1fr; gap: 34px; }
  .section { padding: 64px 0; }
  h1 { font-size: 2.3rem; }
}

@media (max-width: 520px) {
  .card-grid, .process-grid, .decor-grid, .gallery-grid, .value-grid { grid-template-columns: 1fr; }
  .stat-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 400px) {
  .container { padding: 0 18px; }
  .btn { padding: 13px 20px; font-size: 0.88rem; }
  .hero-actions, .header-cta { width: 100%; }
  .hero-actions .btn { width: 100%; }
  .brand-text small { display: none; }
  .brand { font-size: 1.15rem; gap: 8px; }
  .brand-logo { height: 34px; }
  .cta-banner { padding: 32px 20px; }
}

@media (max-width: 340px) {
  .brand-text { display: none; }
}

/* Mobile nav drawer */
.mobile-nav {
  position: fixed; inset: 0;
  background: var(--color-bg);
  z-index: 99;
  display: none;
  flex-direction: column;
  padding: 120px 32px 40px;
  gap: 26px;
}
.mobile-nav.is-open { display: flex; }
@media (min-width: 1025px) {
  .mobile-nav { display: none !important; }
}
.mobile-nav a { font-family: var(--font-display); font-size: 1.6rem; }
.mobile-nav a.active { color: var(--color-terracotta); }
.mobile-nav .mobile-nav-cta {
  font-family: var(--font-body);
  font-size: 0.95rem;
  margin-top: 10px;
  align-self: flex-start;
}