* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue",
    Arial, "Noto Sans", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color: #1f2933;
  background-color: #f5f7fa;
}

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

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

a:hover {
  text-decoration: underline;
}

.container {
  width: 100%;
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 16px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background-color: #ffffffcc;
  backdrop-filter: blur(8px);
  border-bottom: 1px solid #e1e4ea;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 0;
}

.logo {
  font-weight: 700;
  font-size: 20px;
  color: #2563eb;
}

.nav {
  display: flex;
  gap: 16px;
  font-size: 14px;
}

.nav a {
  padding: 6px 10px;
  border-radius: 999px;
  transition: background-color 0.2s ease, color 0.2s ease;
}

.nav a:hover {
  background-color: #2563eb0f;
  color: #1d4ed8;
}

.hero {
  background: radial-gradient(circle at top left, #dbeafe, #eff6ff 40%, #f9fafb);
}

.hero-inner {
  display: grid;
  grid-template-columns: minmax(0, 3fr) minmax(0, 2.5fr);
  gap: 40px;
  align-items: center;
  padding: 64px 0 56px;
}

.hero-text h1 {
  font-size: clamp(28px, 3vw, 36px);
  margin: 0 0 16px;
  color: #111827;
}

.hero-text p {
  margin: 0 0 24px;
  line-height: 1.7;
  color: #4b5563;
}

.btn-primary {
  display: inline-block;
  padding: 10px 18px;
  border-radius: 999px;
  border: none;
  background: linear-gradient(135deg, #2563eb, #16a085);
  color: #ffffff;
  font-size: 14px;
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.btn-primary:hover {
  text-decoration: none;
  transform: translateY(-1px);
  box-shadow: 0 10px 20px rgba(37, 99, 235, 0.25);
}

.btn-primary:disabled {
  opacity: 0.65;
  box-shadow: none;
  cursor: not-allowed;
}

.btn-full {
  width: 100%;
  text-align: center;
}

.hero-image {
  position: relative;
  min-height: 220px;
}

.hero-circle {
  position: absolute;
  inset: 10% 0 0 10%;
  border-radius: 32px;
  background: radial-gradient(circle at 20% 20%, #93c5fd, #22c55e);
  opacity: 0.18;
}

.hero-card {
  position: absolute;
  right: 10px;
  bottom: 10px;
  padding: 16px 18px;
  border-radius: 18px;
  background-color: #ffffff;
  box-shadow: 0 10px 30px rgba(15, 23, 42, 0.12);
  max-width: 220px;
}

.hero-card-title {
  display: block;
  font-size: 13px;
  color: #6b7280;
  margin-bottom: 4px;
}

.hero-card-text {
  font-size: 14px;
  font-weight: 600;
  color: #111827;
}

.section {
  padding: 56px 0;
}

.section-alt {
  background-color: #ffffff;
}

.section-title {
  font-size: 22px;
  margin: 0 0 8px;
  color: #111827;
}

.section-subtitle {
  margin: 0 0 24px;
  color: #6b7280;
  font-size: 14px;
}

.cards {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
}

.card {
  background-color: #ffffff;
  border-radius: 16px;
  padding: 20px 18px 18px;
  box-shadow: 0 8px 20px rgba(15, 23, 42, 0.06);
  border: 1px solid #e5e7eb;
}

.card h3 {
  margin: 0 0 10px;
  font-size: 18px;
}

.card p {
  margin: 0 0 10px;
  font-size: 14px;
  color: #4b5563;
}

.card ul {
  margin: 0;
  padding-left: 18px;
  font-size: 13px;
  color: #6b7280;
}

.card li + li {
  margin-top: 4px;
}

.knowledge-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
}

.knowledge-item {
  background-color: #f9fafb;
  border-radius: 14px;
  padding: 16px 16px 14px;
  border: 1px solid #e5e7eb;
}

.knowledge-item h3 {
  margin: 0 0 8px;
  font-size: 16px;
}

.knowledge-item p {
  margin: 0 0 8px;
  font-size: 13px;
  color: #4b5563;
}

.tag {
  display: inline-block;
  padding: 3px 8px;
  border-radius: 999px;
  background-color: #dbeafe;
  color: #1d4ed8;
  font-size: 12px;
}

.about {
  display: grid;
  grid-template-columns: minmax(0, 3fr) minmax(0, 2fr);
  gap: 24px;
  align-items: center;
}

.about-text p {
  margin: 0 0 10px;
  color: #4b5563;
  line-height: 1.7;
}

.about-highlights {
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.highlight {
  background-color: #ffffff;
  border-radius: 14px;
  padding: 14px 16px;
  border: 1px solid #e5e7eb;
  box-shadow: 0 6px 16px rgba(15, 23, 42, 0.06);
}

.highlight-number {
  display: block;
  font-size: 22px;
  font-weight: 700;
  color: #2563eb;
}

.highlight-label {
  font-size: 13px;
  color: #6b7280;
}

.contact {
  display: grid;
  grid-template-columns: minmax(0, 3fr) minmax(0, 3fr);
  gap: 24px;
}

.contact-info ul {
  padding-left: 18px;
  margin: 8px 0 0;
  font-size: 14px;
  color: #4b5563;
}

.contact-info li + li {
  margin-top: 4px;
}

.contact-form h3 {
  margin-top: 0;
  margin-bottom: 10px;
}

.contact-form form {
  background-color: #ffffff;
  border-radius: 16px;
  padding: 16px 16px 14px;
  border: 1px solid #e5e7eb;
}

.contact-form label {
  display: block;
  font-size: 13px;
  color: #374151;
  margin-bottom: 10px;
}

.contact-form input,
.contact-form textarea {
  width: 100%;
  margin-top: 4px;
  border-radius: 10px;
  border: 1px solid #d1d5db;
  padding: 8px 10px;
  font-size: 13px;
  font-family: inherit;
  outline: none;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

.contact-form input:focus,
.contact-form textarea:focus {
  border-color: #2563eb;
  box-shadow: 0 0 0 1px #2563eb33;
}

.site-footer {
  border-top: 1px solid #e5e7eb;
  background-color: #ffffff;
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 8px;
  font-size: 12px;
  color: #6b7280;
  padding: 14px 0;
}

.footer-links a {
  color: #4b5563;
}

.footer-links a:hover {
  color: #1d4ed8;
}

@media (max-width: 900px) {
  .hero-inner {
    grid-template-columns: minmax(0, 1fr);
    padding: 40px 0 32px;
  }

  .hero-image {
    order: -1;
    min-height: 160px;
  }

  .cards,
  .knowledge-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .about,
  .contact {
    grid-template-columns: minmax(0, 1fr);
  }

  .about-highlights {
    flex-direction: row;
    flex-wrap: wrap;
  }

  .highlight {
    flex: 1 1 30%;
  }
}

@media (max-width: 640px) {
  .header-inner {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
  }

  .nav {
    flex-wrap: wrap;
    gap: 8px;
  }

  .hero-inner {
    padding-top: 28px;
  }

  .section {
    padding: 40px 0;
  }

  .cards,
  .knowledge-list {
    grid-template-columns: minmax(0, 1fr);
  }

  .about-highlights {
    flex-direction: column;
  }
}