/* Yadan Tech landing page */
:root {
  color-scheme: dark;
  color: #ffffff;
  background: #050a1d;
  font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 16px;
  line-height: 1.6;
}
* {
  box-sizing: border-box;
}
body {
  margin: 0;
  min-height: 100vh;
  background: radial-gradient(circle at top, rgba(38, 81, 243, 0.18), transparent 40%),
    linear-gradient(180deg, #07112a 0%, #02050f 100%);
}
img {
  max-width: 100%;
  display: block;
}
a {
  color: inherit;
  text-decoration: none;
}
.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  backdrop-filter: blur(18px);
  background: rgba(3, 9, 28, 0.88);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}
.topbar-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1rem 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.85rem;
  color: #fff;
  font-weight: 700;
  letter-spacing: 0.02em;
}
.logo {
  width: 48px;
  height: 48px;
}
.nav-links {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}
.nav-links a {
  color: #dbe2ff;
  padding: 0.6rem 0.85rem;
  border-radius: 999px;
  transition: background 0.2s ease, color 0.2s ease;
}
.nav-links a:hover,
.nav-links a:focus-visible {
  background: rgba(255, 255, 255, 0.08);
  color: #fff;
}
.nav-cta {
  background: #2873ff;
  color: #fff;
  padding: 0.8rem 1rem;
}
header.hero-section {
  position: relative;
  min-height: 82vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 4rem 2rem;
  text-align: center;
}
.hero-overlay {
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at top right, rgba(16, 145, 255, 0.25), transparent 30%),
    linear-gradient(135deg, rgba(0, 0, 0, 0.45), transparent 55%);
}
.hero-content {
  position: relative;
  max-width: 900px;
  z-index: 1;
}
.eyebrow {
  margin: 0 auto 1rem;
  display: inline-flex;
  padding: 0.65rem 1.15rem;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.08);
  color: #a0c8ff;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  font-size: 0.8rem;
}
h1 {
  font-size: clamp(2.8rem, 4vw, 4.4rem);
  margin: 0 0 1rem;
  letter-spacing: -0.03em;
}
.hero-content p {
  margin: 0 auto 1.4rem;
  color: #d0d7f4;
  font-size: 1.05rem;
}
.hero-sm {
  font-size: 1.05rem;
  color: #a8c6ff;
  margin-bottom: 2rem;
}
.hero-actions {
  display: flex;
  justify-content: center;
  gap: 1rem;
  flex-wrap: wrap;
}
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 180px;
  padding: 1rem 1.5rem;
  border-radius: 999px;
  font-weight: 700;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
  cursor: pointer;
}
.btn:hover {
  transform: translateY(-2px);
}
.primary {
  background: #2873ff;
  color: #fff;
  box-shadow: 0 16px 40px rgba(40, 115, 255, 0.22);
}
.secondary {
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.12);
  color: #eef2ff;
}
.link-button {
  display: inline-flex;
  align-items: center;
  padding: 0.85rem 1.15rem;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.08);
  color: #eef2ff;
  font-weight: 700;
  transition: background 0.2s ease;
}
.link-button:hover {
  background: rgba(255, 255, 255, 0.14);
}
main {
  padding: 3rem 2rem 4rem;
  max-width: 1200px;
  margin: 0 auto;
}
.section {
  margin-bottom: 3.5rem;
}
.section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 1.5rem;
}
.section h2 {
  font-size: clamp(2rem, 3vw, 2.8rem);
  margin: 0;
}
.section p {
  color: #c8d4ff;
  max-width: 760px;
}
.cards-grid .cards {
  display: grid;
  gap: 1.4rem;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}
.card {
  padding: 1.75rem;
  border-radius: 24px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.08);
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.12);
}
.card h3 {
  margin-top: 0;
  color: #fff;
}
.card p {
  margin: 0.75rem 0 0;
  color: #d8e0ff;
}
.split {
  display: grid;
  grid-template-columns: 1.45fr 0.85fr;
  gap: 2rem;
  align-items: start;
}
.feature-list {
  list-style: none;
  padding: 0;
  margin: 1.75rem 0 0;
  display: grid;
  gap: 1rem;
}
.feature-list li {
  padding: 1rem 1.15rem;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.08);
}
.info-panel {
  padding: 2rem;
  border-radius: 28px;
  background: linear-gradient(180deg, rgba(20, 72, 155, 0.95), rgba(17, 39, 88, 0.96));
  box-shadow: 0 24px 56px rgba(6, 22, 61, 0.25);
}
.info-panel h3 {
  margin-top: 0;
}
.platform-list {
  display: grid;
  gap: 0.9rem;
  margin-top: 1.5rem;
}
.platform-list span {
  display: inline-flex;
  padding: 0.85rem 1rem;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.08);
  color: #eef4ff;
}
.expertise-row .expertise-grid {
  display: grid;
  gap: 1rem;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
}
.expertise-card {
  display: block;
  padding: 1.4rem;
  border-radius: 20px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.08);
  text-align: center;
  color: #eef2ff;
  font-weight: 700;
  transition: transform 0.2s ease, background 0.2s ease;
}
.expertise-card:hover {
  background: rgba(255, 255, 255, 0.08);
  transform: translateY(-2px);
}
.cta-panel {
  display: grid;
  grid-template-columns: 1.5fr 1fr;
  gap: 2rem;
  padding: 2.5rem;
  border-radius: 28px;
  background: rgba(14, 35, 77, 0.92);
  border: 1px solid rgba(255, 255, 255, 0.08);
}
.contact-card {
  padding: 1.6rem 1.75rem;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 22px;
}
.contact-card p {
  margin: 0.85rem 0;
}
.page-content {
  padding: 3rem 2rem 4rem;
  max-width: 1100px;
  margin: 0 auto;
}
.form-card {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 28px;
  padding: 2rem;
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.15);
  max-width: 700px;
  margin-top: 1.5rem;
}
label {
  display: block;
  margin-bottom: 1rem;
  color: #d7e0ff;
  font-weight: 600;
}
input,
textarea {
  width: 100%;
  padding: 0.95rem 1rem;
  margin-top: 0.5rem;
  border-radius: 16px;
  border: 1px solid rgba(255, 255, 255, 0.14);
  background: rgba(255, 255, 255, 0.06);
  color: #f7fbff;
  font-size: 1rem;
}
input:focus,
textarea:focus {
  outline: none;
  border-color: #4b93ff;
  box-shadow: 0 0 0 4px rgba(40, 115, 255, 0.12);
}
.success-message {
  display: none;
  margin-top: 1rem;
  color: #b5ffd6;
  background: rgba(40, 166, 130, 0.16);
  padding: 1rem 1.25rem;
  border-radius: 16px;
  border: 1px solid rgba(76, 217, 150, 0.25);
}
footer {
  padding: 1.75rem 2rem 2.5rem;
  text-align: center;
  color: #8ea5ff;
}
.social-links {
  display: flex;
  justify-content: center;
  gap: 1rem;
  margin-bottom: 1rem;
}
.social-links a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.08);
  color: #dbe2ff;
  transition: background 0.2s ease, transform 0.2s ease;
}
.social-links a:hover {
  background: rgba(255, 255, 255, 0.14);
  transform: scale(1.1);
}
@media (max-width: 860px) {
  .split,
  .cta-panel {
    grid-template-columns: 1fr;
  }
}
@media (max-width: 680px) {
  .topbar-inner,
  .section-header {
    flex-direction: column;
    align-items: flex-start;
  }
}
@media (max-width: 520px) {
  .hero-section {
    padding: 3rem 1.25rem;
  }
  .hero-actions {
    flex-direction: column;
  }
}