:root {
  --bg: #f3f7fc;
  --surface: #ffffff;
  --surface-soft: #f7faff;
  --text: #162033;
  --muted: #5d6b85;
  --line: #d9e3f0;
  --primary: #0f62fe;
  --primary-dark: #0b4fd0;
  --accent: #18a0fb;
  --success: #1d9b6c;
  --shadow: 0 20px 60px rgba(15, 38, 95, 0.12);
  --radius-lg: 28px;
  --radius-md: 18px;
  --radius-sm: 12px;
  --container: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Microsoft YaHei", "PingFang SC", "Segoe UI", sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at top right, rgba(24, 160, 251, 0.18), transparent 26%),
    linear-gradient(180deg, #eef4fb 0%, #f8fbff 35%, #ffffff 100%);
  line-height: 1.6;
}

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

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

button,
a {
  -webkit-tap-highlight-color: transparent;
}

.site-shell {
  min-height: 100vh;
}

.container {
  width: min(calc(100% - 40px), var(--container));
  margin: 0 auto;
}

.section {
  padding: 92px 0;
}

.section-muted {
  background: rgba(255, 255, 255, 0.78);
  backdrop-filter: blur(12px);
}

.section-heading {
  max-width: 760px;
  margin: 0 auto 42px;
  text-align: center;
}

.section-heading-left {
  margin-left: 0;
  text-align: left;
}

.section-heading h2,
.section-heading h3,
.hero-copy h1 {
  margin: 0;
  letter-spacing: -0.02em;
  line-height: 1.2;
}

.section-heading h2 {
  font-size: clamp(1.95rem, 3vw, 2.8rem);
}

.section-heading p,
.hero-desc,
.feature-card p,
.version-card p,
.review-card p,
.faq-answer p,
.footer-brand p,
.footer-links a,
.brand-text span {
  color: var(--muted);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 14px;
  color: var(--primary);
  font-size: 0.95rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.eyebrow::before {
  content: "";
  width: 34px;
  height: 2px;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--primary), transparent);
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(248, 251, 255, 0.78);
  border-bottom: 1px solid rgba(217, 227, 240, 0.7);
  backdrop-filter: blur(14px);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 86px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  min-width: 0;
}

.brand img {
  width: 50px;
  height: 50px;
  border-radius: 14px;
  box-shadow: 0 10px 25px rgba(15, 98, 254, 0.16);
}

.brand-text {
  display: grid;
  gap: 2px;
}

.brand-text strong {
  font-size: 1.04rem;
}

.brand-text span {
  font-size: 0.87rem;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 24px;
  font-weight: 600;
}

.nav-menu a:not(.btn) {
  position: relative;
  color: #32415f;
}

.nav-menu a:not(.btn)::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -8px;
  width: 100%;
  height: 2px;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.24s ease;
  background: var(--primary);
}

.nav-menu a:not(.btn):hover::after {
  transform: scaleX(1);
}

.nav-toggle {
  display: none;
  padding: 0;
  border: 0;
  background: transparent;
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  margin: 5px 0;
  background: var(--text);
  border-radius: 999px;
}

.hero {
  position: relative;
  overflow: hidden;
  padding: 84px 0 60px;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 20px auto auto 50%;
  width: 700px;
  height: 700px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(15, 98, 254, 0.14), transparent 62%);
  transform: translateX(-6%);
  pointer-events: none;
}

.hero-grid {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(420px, 0.98fr);
  gap: 42px;
  align-items: center;
}

.hero-copy h1 {
  max-width: 720px;
  font-size: clamp(1.72rem, 3.43vw, 2.98rem);
}

.hero-desc {
  max-width: 660px;
  margin: 22px 0 0;
  font-size: 1.08rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 30px;
}

.hero-points {
  display: grid;
  grid-template-columns: repeat(1, minmax(0, 1fr));
  gap: 12px;
  margin: 28px 0 0;
  padding: 0;
  list-style: none;
}

.hero-points li {
  position: relative;
  padding-left: 28px;
  color: #31425f;
  font-weight: 600;
}

.hero-points li::before {
  content: "";
  position: absolute;
  top: 10px;
  left: 0;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--success), #59c99d);
  box-shadow: 0 0 0 5px rgba(29, 155, 108, 0.12);
}

.hero-visual {
  display: flex;
  justify-content: flex-end;
}

.visual-card {
  width: min(100%, 560px);
  padding: 18px;
  border: 1px solid rgba(217, 227, 240, 0.95);
  border-radius: calc(var(--radius-lg) + 4px);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.94), rgba(244, 248, 255, 0.98));
  box-shadow: var(--shadow);
}

.visual-card img {
  width: 100%;
  border-radius: 22px;
}

.card-grid {
  display: grid;
  gap: 22px;
}

.advantages-grid {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.feature-card,
.version-card,
.review-card,
.faq-item {
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: var(--surface);
  box-shadow: 0 18px 46px rgba(15, 38, 95, 0.06);
}

.feature-card {
  padding: 28px;
}

.feature-card h3,
.version-card h3,
.review-card h3,
.footer-links h3 {
  margin: 16px 0 10px;
  font-size: 1.18rem;
}

.icon-chip {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  border-radius: 14px;
  color: var(--primary);
  font-weight: 800;
  background: rgba(15, 98, 254, 0.1);
}

.versions-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
  align-items: stretch;
}

.version-card {
  position: relative;
  padding: 30px;
}

.version-card.featured {
  border-color: rgba(15, 98, 254, 0.22);
  background: linear-gradient(180deg, #f8fbff 0%, #ffffff 100%);
}

.badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 56px;
  padding: 6px 12px;
  border-radius: 999px;
  color: #ffffff;
  font-size: 0.8rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--primary), var(--accent));
}

.version-card ul {
  margin: 18px 0 24px;
  padding-left: 18px;
  color: #344360;
}

.version-card li + li {
  margin-top: 10px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 22px;
  border-radius: 14px;
  border: 1px solid transparent;
  font-weight: 700;
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease, background 0.2s ease;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn-primary {
  color: #ffffff;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  box-shadow: 0 16px 34px rgba(15, 98, 254, 0.24);
}

.btn-primary:hover {
  box-shadow: 0 20px 38px rgba(15, 98, 254, 0.28);
}

.btn-secondary {
  color: var(--primary);
  border-color: rgba(15, 98, 254, 0.18);
  background: rgba(15, 98, 254, 0.06);
}

.btn-sm {
  min-height: 42px;
  padding: 0 18px;
}

.btn-block {
  width: 100%;
}

.reviews-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.review-card {
  padding: 28px;
}

.review-top {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 18px;
}

.review-top h3 {
  margin: 0 0 4px;
}

.review-top p {
  margin: 0;
  font-size: 0.92rem;
}

.avatar {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 52px;
  height: 52px;
  border-radius: 50%;
  color: #ffffff;
  font-weight: 800;
  background: linear-gradient(135deg, #0f62fe, #18a0fb);
}

.faq-wrap {
  display: grid;
  grid-template-columns: minmax(320px, 0.88fr) minmax(0, 1.12fr);
  gap: 28px;
  align-items: start;
}

.faq-list {
  display: grid;
  gap: 16px;
}

.faq-item {
  overflow: hidden;
}

.faq-question {
  position: relative;
  width: 100%;
  padding: 22px 60px 22px 24px;
  border: 0;
  background: transparent;
  color: var(--text);
  text-align: left;
  font-size: 1rem;
  font-weight: 700;
  cursor: pointer;
}

.faq-question::after,
.faq-question::before {
  content: "";
  position: absolute;
  top: 50%;
  right: 24px;
  width: 14px;
  height: 2px;
  background: var(--primary);
  border-radius: 999px;
  transform: translateY(-50%);
  transition: transform 0.2s ease;
}

.faq-question::before {
  transform: translateY(-50%) rotate(90deg);
}

.faq-item.is-open .faq-question::before {
  transform: translateY(-50%) rotate(0deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.24s ease;
}

.faq-item.is-open .faq-answer {
  max-height: 220px;
}

.faq-answer p {
  margin: 0;
  padding: 0 24px 22px;
}

.site-footer {
  color: #dfe8f7;
  background: #09172c;
}

.footer-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) repeat(3, minmax(0, 0.8fr));
  gap: 28px;
  padding: 60px 0 28px;
}

.brand-footer img {
  box-shadow: none;
}

.footer-brand p {
  max-width: 420px;
  margin: 18px 0 0;
  color: rgba(223, 232, 247, 0.78);
}

.footer-links {
  display: grid;
  align-content: start;
  gap: 12px;
}

.footer-links h3 {
  margin-top: 0;
  color: #ffffff;
}

.footer-links a {
  color: rgba(223, 232, 247, 0.76);
}

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

.footer-bottom {
  padding: 18px 0 34px;
  border-top: 1px solid rgba(223, 232, 247, 0.12);
}

.footer-bottom p {
  margin: 0;
  color: rgba(223, 232, 247, 0.7);
  text-align: center;
}

@media (max-width: 1100px) {
  .advantages-grid,
  .versions-grid,
  .reviews-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .hero-grid,
  .faq-wrap,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .hero-visual {
    justify-content: flex-start;
  }
}

@media (max-width: 780px) {
  .section {
    padding: 72px 0;
  }

  .nav {
    min-height: 78px;
  }

  .nav-toggle {
    display: block;
  }

  .nav-menu {
    position: absolute;
    top: calc(100% + 10px);
    left: 20px;
    right: 20px;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 12px;
    padding: 18px;
    border: 1px solid var(--line);
    border-radius: var(--radius-md);
    background: rgba(255, 255, 255, 0.98);
    box-shadow: var(--shadow);
  }

  .nav-menu.is-open {
    display: flex;
  }

  .hero {
    padding-top: 56px;
  }

  .hero-copy h1 {
    font-size: clamp(1.4rem, 5.6vw, 2.1rem);
  }

  .advantages-grid,
  .versions-grid,
  .reviews-grid {
    grid-template-columns: 1fr;
  }

  .feature-card,
  .version-card,
  .review-card {
    padding: 24px;
  }

  .footer-grid {
    padding-top: 48px;
  }
}