/* === Reset & Base === */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  color: #1a1a1a;
  background: #fff;
  overflow: hidden;
  -webkit-font-smoothing: antialiased;
}

/* === Scroll Container === */
.scroll-container {
  height: 100vh;
  overflow-y: auto;
  scroll-snap-type: y mandatory;
  scroll-behavior: smooth;
}

/* === Sections === */
.section {
  min-height: 100vh;
  scroll-snap-align: start;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  padding: 100px 24px 60px;
}
.section-content {
  max-width: 900px;
  width: 100%;
  text-align: center;
}
.section h1 {
  font-size: clamp(2.4rem, 6vw, 4rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.1;
  margin-bottom: 16px;
}
.section h2 {
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.15;
  margin-bottom: 12px;
}
.section-sub {
  font-size: clamp(1rem, 2.5vw, 1.25rem);
  color: #555;
  font-weight: 400;
  line-height: 1.5;
  margin-bottom: 48px;
}

/* Section backgrounds */
.section-hero { background: #fafafa; }
.section-ads { background: #f0f4ff; }
.section-marketing { background: #f5f0ff; }
.section-ai { background: #fff8eb; }
.section-contact { background: #fafafa; }

/* Section icon */
.section-icon { margin-bottom: 32px; }

/* === Hero logos === */
.hero-logos {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  margin-bottom: 48px;
  max-width: 560px;
  margin-left: auto;
  margin-right: auto;
}
.hero-logo-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}
.hero-logo-card span {
  font-size: 0.75rem;
  font-weight: 500;
  color: #888;
  white-space: nowrap;
}

/* === Detail cards === */
.section-details {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  text-align: left;
}
.detail-card {
  background: rgba(255,255,255,0.7);
  backdrop-filter: blur(8px);
  border: 1px solid rgba(0,0,0,0.06);
  border-radius: 12px;
  padding: 28px 24px;
}
.detail-card h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 8px;
}
.detail-card p {
  font-size: 0.9rem;
  color: #666;
  line-height: 1.55;
}

/* === Header === */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 0 32px;
  height: 64px;
  display: flex;
  align-items: center;
  background: rgba(255,255,255,0.72);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(0,0,0,0.06);
  transition: background 0.3s;
}
.header-inner {
  display: flex;
  align-items: center;
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
}
.header-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: inherit;
}
.header-logo {
  color: #1a1a1a;
  transition: color 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}
.logo-cube {
  transition: x 0.6s cubic-bezier(0.4, 0, 0.2, 1),
              y 0.6s cubic-bezier(0.4, 0, 0.2, 1),
              fill 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}
.header-brand-name {
  font-size: 1rem;
  font-weight: 600;
  letter-spacing: -0.02em;
  transition: color 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

/* === Nav dots === */
.nav-dots {
  position: fixed;
  right: 28px;
  top: 50%;
  transform: translateY(-50%);
  z-index: 100;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.nav-dot {
  width: 12px;
  height: 12px;
  border: none;
  background: none;
  padding: 0;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
}
.nav-dot span {
  display: block;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: rgba(0,0,0,0.15);
  transition: transform 0.3s, background 0.3s;
}
.nav-dot.active span {
  background: #1a1a1a;
  transform: scale(1.4);
}

/* === Scroll indicator === */
.scroll-indicator {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
}
.scroll-indicator-line {
  width: 1px;
  height: 48px;
  background: linear-gradient(to bottom, #1a1a1a, transparent);
  animation: scrollPulse 2s ease-in-out infinite;
}
@keyframes scrollPulse {
  0%, 100% { opacity: 1; transform: scaleY(1); }
  50% { opacity: 0.3; transform: scaleY(0.6); }
}

/* === Contact form === */
.contact-form {
  max-width: 440px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 14px;
}
.form-group input,
.form-group textarea {
  width: 100%;
  padding: 14px 18px;
  font-family: inherit;
  font-size: 0.95rem;
  border: 1px solid #ddd;
  border-radius: 10px;
  background: #fff;
  color: #1a1a1a;
  outline: none;
  transition: border-color 0.2s;
  resize: vertical;
}
.form-group input:focus,
.form-group textarea:focus {
  border-color: #1a1a1a;
}
.btn-submit {
  padding: 14px 32px;
  font-family: inherit;
  font-size: 1rem;
  font-weight: 600;
  color: #fff;
  background: #1a1a1a;
  border: none;
  border-radius: 10px;
  cursor: pointer;
  transition: opacity 0.2s;
}
.btn-submit:hover { opacity: 0.85; }

/* === Responsive === */
@media (max-width: 768px) {
  .hero-logos {
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
    max-width: 280px;
  }
  .section-details {
    grid-template-columns: 1fr;
    gap: 16px;
  }
  .nav-dots { right: 14px; gap: 10px; }
  .header { padding: 0 20px; }
  .section { padding: 80px 20px 40px; }
  .section-icon svg { width: 80px; height: 80px; }
}

@media (max-width: 480px) {
  .hero-logos { grid-template-columns: repeat(2, 1fr); }
  .hero-logo-card svg { width: 56px; height: 56px; }
}