* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Microsoft YaHei", Arial, sans-serif;
  color: #10203f;
  background: linear-gradient(135deg, #eef6ff 0%, #ffffff 45%, #dcebff 100%);
  line-height: 1.7;
}

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

.topbar {
  max-width: 1280px;
  margin: 0 auto;
  padding: 22px 24px;
  display: flex;
  align-items: center;
  gap: 28px;
}

.site-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 24px;
  font-weight: 900;
  color: #0d6cff;
}

.logo-icon {
  width: 42px;
  height: 42px;
  border-radius: 13px;
  background: #0d6cff;
  color: white;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.nav {
  display: flex;
  gap: 22px;
  margin-left: auto;
  font-weight: 700;
  color: #30405f;
}

.nav a:hover {
  color: #0d6cff;
}

.lang-select {
  border: 1px solid #dce8fa;
  background: white;
  border-radius: 999px;
  padding: 9px 14px;
  color: #30405f;
}

main {
  max-width: 1280px;
  margin: 0 auto;
  padding: 20px 24px 60px;
}

.hero {
  min-height: 620px;
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 42px;
  align-items: center;
}

.eyebrow {
  display: inline-block;
  padding: 7px 14px;
  border-radius: 999px;
  background: #eaf3ff;
  color: #0d6cff;
  font-weight: 800;
  margin-bottom: 22px;
}

.hero h1 {
  font-size: clamp(42px, 6vw, 76px);
  line-height: 1.08;
  letter-spacing: -2px;
  margin-bottom: 24px;
}

.hero-desc {
  max-width: 680px;
  font-size: 20px;
  color: #4d5f7c;
  margin-bottom: 30px;
}

.hero-actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 28px;
}

.btn {
  padding: 13px 22px;
  border-radius: 999px;
  font-weight: 900;
  transition: 0.25s;
}

.btn.primary {
  background: #0d6cff;
  color: white;
  box-shadow: 0 15px 32px rgba(13, 108, 255, 0.28);
}

.btn.ghost {
  background: white;
  border: 1px solid #dce8fa;
  color: #0d6cff;
}

.btn:hover {
  transform: translateY(-3px);
}

.search-box input {
  width: 100%;
  max-width: 560px;
  padding: 16px 20px;
  border: 1px solid #dce8fa;
  border-radius: 18px;
  font-size: 16px;
  box-shadow: 0 14px 32px rgba(16, 60, 120, 0.08);
}

.hero-card {
  background: rgba(255, 255, 255, 0.9);
  border: 1px solid rgba(255, 255, 255, 0.95);
  border-radius: 28px;
  box-shadow: 0 28px 70px rgba(42, 100, 180, 0.22);
  padding: 22px;
}

.browser-top {
  display: flex;
  gap: 10px;
  margin-bottom: 22px;
}

.browser-top span {
  width: 14px;
  height: 14px;
  border-radius: 50%;
}

.browser-top span:nth-child(1) {
  background: #ff4d4f;
}

.browser-top span:nth-child(2) {
  background: #ffbe2e;
}

.browser-top span:nth-child(3) {
  background: #28c840;
}

.preview-grid,
.tool-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
}

.category-card,
.tool-card,
.guide-card,
.feature-card {
  background: white;
  border: 1px solid #e8eef8;
  border-radius: 20px;
  padding: 20px;
  box-shadow: 0 12px 28px rgba(16, 60, 120, 0.08);
  transition: 0.25s;
}

.category-card:hover,
.tool-card:hover,
.guide-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 18px 35px rgba(16, 90, 200, 0.14);
}

.category-icon,
.tool-icon {
  width: 52px;
  height: 52px;
  border-radius: 15px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 900;
  margin-bottom: 12px;
}

.category-card h3,
.tool-card h3,
.guide-card h3 {
  font-size: 19px;
  margin-bottom: 8px;
}

.category-card p,
.tool-card p,
.guide-card p,
.feature-card p {
  color: #65748c;
  font-size: 14px;
}

.features {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 22px;
  margin-top: 20px;
}

.feature-card strong {
  display: block;
  font-size: 19px;
  margin-bottom: 8px;
}

.ad-box {
  margin-top: 60px;
  min-height: 110px;
  border: 2px dashed #b9ccec;
  border-radius: 22px;
  background: rgba(255, 255, 255, 0.58);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #7b8ca8;
  font-weight: 800;
}

.section {
  margin-top: 76px;
}

.section-title {
  text-align: center;
  margin-bottom: 30px;
}

.section-title h2 {
  font-size: 36px;
  margin-bottom: 10px;
}

.section-title p {
  color: #65748c;
  font-size: 17px;
}

.guide-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
}

.guide-card span,
.badge {
  display: inline-block;
  margin-bottom: 12px;
  padding: 4px 10px;
  border-radius: 999px;
  background: #eef5ff;
  color: #0d6cff;
  font-size: 12px;
  font-weight: 800;
}

.faq-wrap {
  max-width: 900px;
  margin: 0 auto;
  display: grid;
  gap: 16px;
}

details {
  background: white;
  border: 1px solid #e8eef8;
  border-radius: 18px;
  padding: 20px 24px;
  box-shadow: 0 10px 24px rgba(16, 60, 120, 0.06);
}

summary {
  font-size: 18px;
  font-weight: 900;
  cursor: pointer;
}

details p {
  margin-top: 12px;
  color: #65748c;
}

.footer {
  max-width: 1280px;
  margin: 0 auto;
  padding: 38px 24px;
  border-top: 1px solid #dce8fa;
  text-align: center;
  color: #65748c;
}

.footer div {
  display: flex;
  justify-content: center;
  gap: 22px;
  flex-wrap: wrap;
  margin-bottom: 12px;
}

.footer a {
  color: #0d6cff;
  font-weight: 800;
}

.hidden {
  display: none !important;
}

@media (max-width: 980px) {
  .hero {
    grid-template-columns: 1fr;
    min-height: auto;
  }

  .hero-card {
    order: -1;
  }

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

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

  .nav {
    display: none;
  }
}

@media (max-width: 560px) {
  .topbar {
    padding: 16px 14px;
  }

  main {
    padding: 10px 14px 50px;
  }

  .features,
  .guide-grid,
  .preview-grid,
  .tool-grid {
    grid-template-columns: 1fr;
  }

  .hero h1 {
    font-size: 42px;
  }

  .hero-desc {
    font-size: 17px;
  }

  .lang-select {
    max-width: 120px;
  }
}