/* ============================================
   SU HÀO INTERIOR — Design System
   Typography: Cinzel (heading) + Josefin Sans (body)
   Colors: Black #171717 + Gold #D4AF37 + White
   ============================================ */

@import url('https://fonts.googleapis.com/css2?family=Playfair+Display:ital,wght@0,400;0,500;0,600;0,700;1,400&family=Be+Vietnam+Pro:wght@300;400;500;600;700&display=swap');

/* ── Design Tokens ── */
:root {
  /* Colors */
  --color-primary: #171717;
  --color-secondary: #404040;
  --color-cta: #D4AF37;
  --color-cta-hover: #c4a030;
  --color-bg: #FFFFFF;
  --color-bg-alt: #F8F7F4;
  --color-bg-dark: #0a0a0a;
  --color-text: #171717;
  --color-text-muted: #5a5a5a;
  --color-text-light: #888888;
  --color-border: #e5e5e5;
  --color-border-light: #f0f0f0;

  /* Typography */
  --font-heading: 'Playfair Display', Georgia, serif;
  --font-body: 'Be Vietnam Pro', sans-serif;

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;
  --space-4xl: 6rem;
  --space-5xl: 8rem;

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07);
  --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 40px rgba(0, 0, 0, 0.12);

  /* Borders */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --radius-full: 9999px;

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 400ms ease;

  /* Container */
  --container-max: 1200px;
  --container-narrow: 800px;

  /* Navbar */
  --navbar-height: 80px;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-body);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.7;
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

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

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

ul,
ol {
  list-style: none;
}

button {
  font-family: var(--font-body);
  cursor: pointer;
  border: none;
  background: none;
}

/* ── Typography ── */
h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-heading);
  font-weight: 600;
  line-height: 1.2;
  color: var(--color-primary);
  letter-spacing: 0.02em;
}

h1 {
  font-size: clamp(2rem, 5vw, 3.5rem);
}

h2 {
  font-size: clamp(1.5rem, 3.5vw, 2.5rem);
}

h3 {
  font-size: clamp(1.25rem, 2.5vw, 1.75rem);
}

h4 {
  font-size: clamp(1.1rem, 2vw, 1.35rem);
}

p {
  margin-bottom: var(--space-md);
  color: var(--color-text-muted);
}

.text-gold {
  color: var(--color-cta);
}

.text-muted {
  color: var(--color-text-muted);
}

.text-light {
  color: var(--color-text-light);
}

.text-center {
  text-align: center;
}

.text-uppercase {
  text-transform: uppercase;
  letter-spacing: 0.15em;
  font-size: 0.85em;
}

.section-label {
  font-family: var(--font-body);
  text-transform: uppercase;
  letter-spacing: 0.2em;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--color-cta);
  margin-bottom: var(--space-sm);
  display: block;
}

.section-title {
  margin-bottom: var(--space-lg);
}

.section-subtitle {
  font-size: 1.1rem;
  color: var(--color-text-muted);
  max-width: 600px;
  margin: 0 auto var(--space-2xl);
  line-height: 1.8;
  font-weight: 300;
}

/* ── Layout ── */
.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-xl);
}

.container-narrow {
  max-width: var(--container-narrow);
  margin: 0 auto;
  padding: 0 var(--space-xl);
}

section {
  padding: var(--space-4xl) 0;
}

.section-dark {
  background: var(--color-bg-dark);
  color: #fff;
}

.section-dark h2,
.section-dark h3,
.section-dark h4 {
  color: #fff;
}

.section-dark p {
  color: rgba(255, 255, 255, 0.7);
}

.section-alt {
  background: var(--color-bg-alt);
}

.grid {
  display: grid;
  gap: var(--space-xl);
}

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

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

.grid-4 {
  grid-template-columns: repeat(4, 1fr);
}

.flex {
  display: flex;
  align-items: center;
}

.flex-between {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.flex-center {
  display: flex;
  align-items: center;
  justify-content: center;
}

.flex-col {
  display: flex;
  flex-direction: column;
}

.gap-sm {
  gap: var(--space-sm);
}

.gap-md {
  gap: var(--space-md);
}

.gap-lg {
  gap: var(--space-lg);
}

.gap-xl {
  gap: var(--space-xl);
}

/* ── Navbar ── */
.navbar {
  position: fixed;
  top: 16px;
  left: 16px;
  right: 16px;
  z-index: 50;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-radius: var(--radius-lg);
  padding: 0 var(--space-xl);
  height: var(--navbar-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  transition: all var(--transition-base);
  border: 1px solid rgba(0, 0, 0, 0.05);
}

.navbar.scrolled {
  background: rgba(255, 255, 255, 0.97);
  box-shadow: var(--shadow-md);
  top: 8px;
}

.navbar-logo {
  font-family: var(--font-heading);
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--color-primary);
  letter-spacing: 0.05em;
}

.navbar-logo span {
  color: var(--color-cta);
}

.navbar-links {
  display: flex;
  gap: var(--space-xl);
}

.navbar-links a {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--color-secondary);
  position: relative;
  padding: var(--space-xs) 0;
  cursor: pointer;
}

.navbar-links a::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-cta);
  transition: width var(--transition-base);
}

.navbar-links a:hover {
  color: var(--color-primary);
}

.navbar-links a:hover::after,
.navbar-links a.active::after {
  width: 100%;
}

.navbar-cta {
  background: var(--color-primary);
  color: #fff !important;
  padding: 10px 24px;
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 600;
  transition: all var(--transition-fast);
  cursor: pointer;
}

.navbar-cta:hover {
  background: var(--color-cta);
  transform: translateY(-1px);
}

.navbar-cta::after {
  display: none !important;
}

/* Mobile Menu */
.mobile-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 8px;
}

.mobile-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-primary);
  transition: all var(--transition-fast);
}

.mobile-menu {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(255, 255, 255, 0.98);
  backdrop-filter: blur(20px);
  z-index: 99;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-xl);
}

.mobile-menu.active {
  display: flex;
}

.mobile-menu a {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  color: var(--color-primary);
  cursor: pointer;
}

.mobile-menu a:hover {
  color: var(--color-cta);
}

.mobile-close {
  position: absolute;
  top: 32px;
  right: 32px;
  font-size: 2rem;
  cursor: pointer;
  color: var(--color-primary);
  background: none;
  border: none;
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* ── Hero Section ── */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  overflow: hidden;
  padding-top: calc(var(--navbar-height) + 32px);
}

.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.hero-bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(0, 0, 0, 0.65) 0%, rgba(0, 0, 0, 0.3) 50%, rgba(0, 0, 0, 0.1) 100%);
  z-index: 1;
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 700px;
  padding: var(--space-3xl) 0;
}

.hero h1 {
  color: #fff;
  font-size: clamp(2.5rem, 6vw, 4rem);
  line-height: 1.15;
  margin-bottom: var(--space-lg);
}

.hero h1 span {
  color: var(--color-cta);
}

.hero p {
  color: rgba(255, 255, 255, 0.85);
  font-size: 1.15rem;
  margin-bottom: var(--space-2xl);
  font-weight: 300;
  line-height: 1.8;
}

.hero-buttons {
  display: flex;
  gap: var(--space-md);
  flex-wrap: wrap;
}

/* ── Buttons ── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: 14px 32px;
  border-radius: var(--radius-full);
  font-size: 0.95rem;
  font-weight: 600;
  transition: all var(--transition-fast);
  cursor: pointer;
  border: none;
  font-family: var(--font-body);
  letter-spacing: 0.02em;
}

.btn-primary {
  background: var(--color-cta);
  color: #fff;
}

.btn-primary:hover {
  background: var(--color-cta-hover);
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(212, 175, 55, 0.3);
}

.btn-secondary {
  background: transparent;
  color: #fff;
  border: 2px solid rgba(255, 255, 255, 0.5);
}

.btn-secondary:hover {
  border-color: #fff;
  background: rgba(255, 255, 255, 0.1);
}

.btn-outline {
  background: transparent;
  color: var(--color-primary);
  border: 2px solid var(--color-primary);
}

.btn-outline:hover {
  background: var(--color-primary);
  color: #fff;
}

.btn-dark {
  background: var(--color-primary);
  color: #fff;
}

.btn-dark:hover {
  background: #2a2a2a;
  transform: translateY(-2px);
}

.btn-sm {
  padding: 10px 20px;
  font-size: 0.85rem;
}

.btn-lg {
  padding: 18px 40px;
  font-size: 1.05rem;
}

/* ── USP Bar ── */
.usp-bar {
  background: var(--color-primary);
  padding: var(--space-2xl) 0;
}

.usp-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-xl);
  text-align: center;
}

.usp-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-sm);
}

.usp-icon {
  width: 48px;
  height: 48px;
  color: var(--color-cta);
  margin-bottom: var(--space-sm);
}

.usp-number {
  font-family: var(--font-heading);
  font-size: 2rem;
  font-weight: 700;
  color: var(--color-cta);
}

.usp-text {
  color: rgba(255, 255, 255, 0.8);
  font-size: 0.9rem;
  font-weight: 300;
}

/* ── Cards ── */
.project-card {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  cursor: pointer;
  aspect-ratio: 4/3;
}

.project-card img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-slow);
}

.project-card:hover img {
  transform: scale(1.05);
}

.project-card-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(to top, rgba(0, 0, 0, 0.7) 0%, rgba(0, 0, 0, 0) 60%);
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  padding: var(--space-xl);
  transition: all var(--transition-base);
}

.project-card:hover .project-card-overlay {
  background: linear-gradient(to top, rgba(0, 0, 0, 0.85) 0%, rgba(0, 0, 0, 0.2) 70%);
}

.project-card-tag {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  color: var(--color-cta);
  font-weight: 600;
  margin-bottom: var(--space-xs);
}

.project-card-title {
  font-family: var(--font-heading);
  font-size: 1.25rem;
  color: #fff;
  margin-bottom: var(--space-xs);
}

.project-card-meta {
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.6);
  font-weight: 300;
}

/* ── Pricing Tiers ── */
.tier-card {
  background: #fff;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-2xl);
  text-align: center;
  transition: all var(--transition-base);
  cursor: pointer;
  position: relative;
}

.tier-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
}

.tier-card.featured {
  border-color: var(--color-cta);
  box-shadow: 0 0 0 2px var(--color-cta), var(--shadow-lg);
}

.tier-badge {
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--color-cta);
  color: #fff;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 4px 20px;
  border-radius: var(--radius-full);
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.tier-name {
  font-family: var(--font-heading);
  font-size: 1.3rem;
  margin-bottom: var(--space-sm);
}

.tier-price {
  font-family: var(--font-heading);
  font-size: 2rem;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: var(--space-md);
}

.tier-price span {
  font-family: var(--font-body);
  font-size: 0.85rem;
  font-weight: 400;
  color: var(--color-text-muted);
}

.tier-features {
  text-align: left;
  margin-bottom: var(--space-xl);
}

.tier-features li {
  padding: var(--space-sm) 0;
  font-size: 0.9rem;
  color: var(--color-text-muted);
  display: flex;
  align-items: flex-start;
  gap: var(--space-sm);
  border-bottom: 1px solid var(--color-border-light);
}

.tier-features li:last-child {
  border-bottom: none;
}

.check-icon {
  width: 18px;
  height: 18px;
  color: var(--color-cta);
  flex-shrink: 0;
  margin-top: 2px;
}

/* ── Process Timeline ── */
.process-steps {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: var(--space-md);
  position: relative;
}

.process-steps::before {
  content: '';
  position: absolute;
  top: 40px;
  left: 10%;
  right: 10%;
  height: 2px;
  background: var(--color-border);
}

.process-step {
  text-align: center;
  position: relative;
  z-index: 1;
}

.step-number {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  background: var(--color-bg-alt);
  border: 2px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto var(--space-md);
  transition: all var(--transition-base);
}

.step-number svg {
  width: 32px;
  height: 32px;
  color: var(--color-cta);
}

.process-step:hover .step-number {
  background: var(--color-cta);
  border-color: var(--color-cta);
}

.process-step:hover .step-number svg {
  color: #fff;
}

.step-label {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: var(--space-xs);
}

.step-desc {
  font-size: 0.8rem;
  color: var(--color-text-light);
  font-weight: 300;
}

/* ── Testimonials ── */
.testimonial-card {
  background: #fff;
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-xl);
  padding: var(--space-2xl);
  position: relative;
}

.testimonial-quote {
  font-size: 1.05rem;
  line-height: 1.8;
  color: var(--color-text-muted);
  margin-bottom: var(--space-lg);
  font-style: italic;
  font-weight: 300;
}

.testimonial-quote::before {
  content: '"';
  font-family: var(--font-heading);
  font-size: 4rem;
  color: var(--color-cta);
  opacity: 0.3;
  position: absolute;
  top: 16px;
  left: 24px;
  line-height: 1;
}

.testimonial-author {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

.testimonial-avatar {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--color-bg-alt);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-heading);
  font-weight: 700;
  color: var(--color-cta);
  font-size: 1.1rem;
}

.testimonial-name {
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--color-primary);
}

.testimonial-project {
  font-size: 0.8rem;
  color: var(--color-text-light);
}

.testimonial-stars {
  display: flex;
  gap: 2px;
  margin-bottom: var(--space-sm);
}

.testimonial-stars svg {
  width: 16px;
  height: 16px;
  color: var(--color-cta);
  fill: var(--color-cta);
}

/* ── Blog Cards ── */
.blog-card {
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: #fff;
  border: 1px solid var(--color-border-light);
  transition: all var(--transition-base);
  cursor: pointer;
}

.blog-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.blog-card-image {
  aspect-ratio: 16/10;
  overflow: hidden;
}

.blog-card-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-slow);
}

.blog-card:hover .blog-card-image img {
  transform: scale(1.05);
}

.blog-card-body {
  padding: var(--space-lg);
}

.blog-card-category {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  color: var(--color-cta);
  font-weight: 600;
  margin-bottom: var(--space-sm);
}

.blog-card-title {
  font-family: var(--font-heading);
  font-size: 1.1rem;
  margin-bottom: var(--space-sm);
  line-height: 1.4;
}

.blog-card-excerpt {
  font-size: 0.9rem;
  color: var(--color-text-muted);
  font-weight: 300;
  margin-bottom: var(--space-md);
  line-height: 1.6;
}

.blog-card-meta {
  font-size: 0.8rem;
  color: var(--color-text-light);
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

/* ── Services ── */
.service-card {
  background: #fff;
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-xl);
  padding: var(--space-2xl);
  transition: all var(--transition-base);
  cursor: pointer;
}

.service-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--color-cta);
}

.service-icon {
  width: 56px;
  height: 56px;
  background: var(--color-bg-alt);
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: var(--space-lg);
  color: var(--color-cta);
  transition: all var(--transition-base);
}

.service-card:hover .service-icon {
  background: var(--color-cta);
  color: #fff;
}

.service-icon svg {
  width: 28px;
  height: 28px;
}

.service-title {
  font-family: var(--font-heading);
  font-size: 1.2rem;
  margin-bottom: var(--space-sm);
}

.service-desc {
  font-size: 0.9rem;
  color: var(--color-text-muted);
  font-weight: 300;
  line-height: 1.7;
}

/* ── Stats Counter ── */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-xl);
  text-align: center;
}

.stat-item {
  padding: var(--space-xl) 0;
}

.stat-number {
  font-family: var(--font-heading);
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--color-cta);
  margin-bottom: var(--space-xs);
}

.stat-label {
  font-size: 0.9rem;
  color: rgba(255, 255, 255, 0.6);
  font-weight: 300;
}

/* ── Contact Form ── */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-3xl);
}

.form-group {
  margin-bottom: var(--space-lg);
}

.form-group label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: var(--space-sm);
  color: var(--color-primary);
}

.form-input,
.form-select,
.form-textarea {
  width: 100%;
  padding: 14px 18px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  font-size: 0.95rem;
  font-family: var(--font-body);
  transition: border-color var(--transition-fast);
  background: #fff;
  color: var(--color-text);
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(23, 23, 23, 0.08);
}

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

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
}

/* ── Footer ── */
.footer {
  background: var(--color-bg-dark);
  color: rgba(255, 255, 255, 0.7);
  padding: var(--space-4xl) 0 var(--space-xl);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: var(--space-3xl);
  margin-bottom: var(--space-3xl);
}

.footer-brand .navbar-logo {
  color: #fff;
  font-size: 1.5rem;
  margin-bottom: var(--space-md);
  display: block;
}

.footer-brand p {
  color: rgba(255, 255, 255, 0.5);
  font-size: 0.9rem;
  line-height: 1.8;
}

.footer-title {
  font-family: var(--font-heading);
  font-size: 0.95rem;
  color: #fff;
  margin-bottom: var(--space-lg);
  letter-spacing: 0.05em;
}

.footer-links li {
  margin-bottom: var(--space-sm);
}

.footer-links a {
  font-size: 0.9rem;
  color: rgba(255, 255, 255, 0.5);
  transition: color var(--transition-fast);
  cursor: pointer;
}

.footer-links a:hover {
  color: var(--color-cta);
}

.footer-social {
  display: flex;
  gap: var(--space-md);
  margin-top: var(--space-md);
}

.footer-social a {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  border: 1px solid rgba(255, 255, 255, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition-fast);
  cursor: pointer;
}

.footer-social a:hover {
  border-color: var(--color-cta);
  background: var(--color-cta);
  color: #fff;
}

.footer-social svg {
  width: 18px;
  height: 18px;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: var(--space-xl);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.4);
}

/* ── Scroll Animations ── */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity var(--transition-slow), transform var(--transition-slow);
}

.reveal.active {
  opacity: 1;
  transform: translateY(0);
}

@media (prefers-reduced-motion: reduce) {
  .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .project-card img,
  .blog-card-image img {
    transition: none;
  }

  .project-card:hover img,
  .blog-card:hover .blog-card-image img {
    transform: none;
  }
}

/* ── Back to Top ── */
.back-to-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--color-primary);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-base);
  z-index: 40;
  border: none;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  background: var(--color-cta);
  transform: translateY(-3px);
}

.back-to-top svg {
  width: 20px;
  height: 20px;
}

/* ── Divider ── */
.divider {
  width: 60px;
  height: 3px;
  background: var(--color-cta);
  margin: var(--space-md) auto;
  border-radius: 2px;
}

/* ── Filter Buttons ── */
.filter-bar {
  display: flex;
  gap: var(--space-sm);
  flex-wrap: wrap;
  justify-content: center;
  margin-bottom: var(--space-2xl);
}

.filter-btn {
  padding: 8px 20px;
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--color-text-muted);
  background: var(--color-bg-alt);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all var(--transition-fast);
  font-family: var(--font-body);
}

.filter-btn:hover {
  color: var(--color-primary);
  border-color: var(--color-border);
}

.filter-btn.active {
  background: var(--color-primary);
  color: #fff;
}

/* ── Page Header ── */
.page-header {
  padding: calc(var(--navbar-height) + 48px) 0 var(--space-3xl);
  background: var(--color-bg-alt);
  text-align: center;
}

.page-header h1 {
  margin-bottom: var(--space-md);
}

.breadcrumb {
  font-size: 0.85rem;
  color: var(--color-text-light);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
}

.breadcrumb a {
  color: var(--color-text-muted);
  cursor: pointer;
}

.breadcrumb a:hover {
  color: var(--color-cta);
}

/* ── CTA Section ── */
.cta-section {
  background: var(--color-primary);
  padding: var(--space-4xl) 0;
  text-align: center;
}

.cta-section h2 {
  color: #fff;
  margin-bottom: var(--space-md);
}

.cta-section p {
  color: rgba(255, 255, 255, 0.7);
  max-width: 500px;
  margin: 0 auto var(--space-xl);
  font-weight: 300;
}

/* ── Responsive ── */
@media (max-width: 1024px) {
  .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }

  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .process-steps {
    grid-template-columns: repeat(3, 1fr);
  }

  .process-steps .process-step:nth-child(n+4) {
    display: none;
  }

  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .contact-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  section {
    padding: var(--space-3xl) 0;
  }

  .container {
    padding: 0 var(--space-md);
  }

  .navbar-links {
    display: none;
  }

  .mobile-toggle {
    display: flex;
  }

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

  .hero h1 {
    font-size: clamp(2rem, 8vw, 2.8rem);
  }

  .hero-content {
    padding: var(--space-xl) 0;
  }

  .usp-grid {
    grid-template-columns: 1fr;
    gap: var(--space-lg);
  }

  .process-steps {
    grid-template-columns: 1fr;
    gap: var(--space-lg);
  }

  .process-steps::before {
    display: none;
  }

  .process-steps .process-step:nth-child(n+4) {
    display: block;
  }

  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-md);
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: var(--space-xl);
  }

  .footer-bottom {
    flex-direction: column;
    gap: var(--space-md);
    text-align: center;
  }

  .form-row {
    grid-template-columns: 1fr;
  }

  .hero-buttons {
    flex-direction: column;
  }

  .btn {
    text-align: center;
    justify-content: center;
  }

  .filter-bar {
    gap: var(--space-xs);
  }

  .filter-btn {
    padding: 6px 14px;
    font-size: 0.8rem;
  }
}

@media (max-width: 375px) {
  html {
    font-size: 14px;
  }

  .navbar {
    padding: 0 var(--space-md);
    left: 8px;
    right: 8px;
    top: 8px;
  }
}