/* 快连官网 - 全站样式（无外部字体/图标库） */
:root {
  --primary: #6E8EFB;
  --primary-dark: #5A7CF0;
  --secondary: #4ADEDE;
  --accent: #FF7BAC;
  --light: #F5F8FF;
  --dark: #1A2332;
  --gray: #66788A;
  --light-gray: #EAEFF5;
  --border-radius: 18px;
  --shadow: 0 15px 40px rgba(0, 0, 0, 0.07);
  --shadow-hover: 0 25px 55px rgba(110, 142, 251, 0.15);
  --transition: all 0.35s cubic-bezier(0.25, 0.46, 0.45, 0.94);
  --font: system-ui, -apple-system, "Segoe UI", "PingFang SC", "Hiragino Sans GB",
    "Microsoft YaHei", "Noto Sans SC", "WenQuanYi Micro Hei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font);
  line-height: 1.75;
  color: var(--dark);
  background-color: #ffffff;
  overflow-x: hidden;
}

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

a {
  color: inherit;
}

.skip-link {
  position: absolute;
  left: 16px;
  top: -80px;
  z-index: 10000;
  background: var(--primary);
  color: #fff;
  padding: 10px 16px;
  border-radius: 10px;
  font-weight: 700;
  text-decoration: none;
}

.skip-link:focus {
  top: 16px;
}

.icon {
  width: 1em;
  height: 1em;
  fill: currentColor;
  display: inline-block;
  vertical-align: -0.15em;
  flex-shrink: 0;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.container {
  width: 100%;
  max-width: 1320px;
  margin: 0 auto;
  padding: 0 32px;
}

/* Header */
.page-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background-color: rgba(255, 255, 255, 0.97);
  backdrop-filter: blur(15px);
  padding: 22px 0;
  box-shadow: 0 4px 25px rgba(0, 0, 0, 0.03);
  transition: var(--transition);
}

.page-header.scrolled {
  padding: 18px 0;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.07);
}

.header-wrapper {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.brand-identity {
  display: flex;
  align-items: center;
}

.main-logo {
  display: flex;
  align-items: center;
  font-size: 28px;
  font-weight: 800;
  color: var(--primary);
  text-decoration: none;
  gap: 12px;
}

.logo-symbol {
  width: 48px;
  height: 48px;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  transform: rotate(-8deg);
  font-size: 22px;
}

.logo-mark {
  height: 36px;
  width: auto;
}

.primary-navigation {
  display: flex;
  list-style: none;
}

.nav-element {
  margin-left: 48px;
}

.nav-link {
  text-decoration: none;
  color: var(--dark);
  font-weight: 700;
  font-size: 17px;
  position: relative;
  padding: 10px 0;
  transition: var(--transition);
}

.nav-link:hover,
.nav-link.active {
  color: var(--primary);
}

.nav-link.active::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: linear-gradient(to right, var(--primary), var(--secondary));
  border-radius: 2px;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 20px;
}

.action-button {
  padding: 16px 38px;
  border-radius: var(--border-radius);
  text-decoration: none;
  font-weight: 700;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  transition: var(--transition);
  cursor: pointer;
  border: none;
  font-size: 17px;
  font-family: var(--font);
  line-height: 1.2;
}

.action-button.primary {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: white;
  box-shadow: 0 10px 30px rgba(110, 142, 251, 0.3);
}

.action-button.primary:hover {
  transform: translateY(-4px);
  box-shadow: 0 16px 40px rgba(110, 142, 251, 0.4);
}

.action-button.outline {
  background-color: transparent;
  color: var(--primary);
  border: 2px solid var(--primary);
}

.action-button.outline:hover {
  background-color: rgba(110, 142, 251, 0.05);
  transform: translateY(-4px);
}

.mobile-nav-toggle {
  display: none;
  font-size: 28px;
  color: var(--dark);
  cursor: pointer;
  background: none;
  border: none;
  padding: 6px;
}

/* Hero */
.hero-section {
  padding: 190px 0 110px;
  background: linear-gradient(135deg, #F0F5FF 0%, #E8EEFF 100%);
  position: relative;
  overflow: hidden;
}

.hero-section::before {
  content: "";
  position: absolute;
  top: -350px;
  right: -180px;
  width: 850px;
  height: 850px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(110, 142, 251, 0.1) 0%, rgba(110, 142, 251, 0) 70%);
}

.hero-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  position: relative;
  z-index: 2;
  gap: 40px;
}

.hero-text-content {
  flex: 1;
  max-width: 640px;
}

.hero-headline {
  font-size: 4.2rem;
  line-height: 1.15;
  margin-bottom: 28px;
  color: var(--dark);
}

.highlighted-text {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: 1.3rem;
  color: var(--gray);
  margin-bottom: 40px;
  max-width: 560px;
}

.feature-highlights {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  margin-bottom: 48px;
}

.highlight-badge {
  display: flex;
  align-items: center;
  background-color: white;
  padding: 16px 26px;
  border-radius: 50px;
  box-shadow: var(--shadow);
  font-weight: 600;
  gap: 12px;
}

.highlight-badge .icon {
  color: var(--primary);
  font-size: 18px;
}

.hero-cta {
  display: flex;
  gap: 24px;
}

.hero-visual {
  flex: 1;
  display: flex;
  justify-content: flex-end;
  position: relative;
}

.hero-image {
  width: 100%;
  max-width: 620px;
  border-radius: var(--border-radius);
  box-shadow: 0 40px 80px rgba(0, 0, 0, 0.18);
  transform: perspective(1800px) rotateY(-15deg) rotateX(4deg);
  transition: var(--transition);
  object-fit: cover;
  aspect-ratio: 1680 / 901;
}

.hero-image:hover {
  transform: perspective(1800px) rotateY(-8deg) rotateX(2deg);
}

.floating-element {
  position: absolute;
  background-color: white;
  border-radius: 18px;
  padding: 26px;
  box-shadow: 0 22px 50px rgba(0, 0, 0, 0.15);
  display: flex;
  align-items: center;
  animation: floatAnimation 7s ease-in-out infinite;
}

.floating-element.servers {
  top: 15%;
  left: -30px;
  animation-delay: 0.4s;
}

.floating-element.speed {
  bottom: 22%;
  right: -40px;
  animation-delay: 0.9s;
}

.element-icon {
  width: 56px;
  height: 56px;
  border-radius: 16px;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  display: flex;
  align-items: center;
  justify-content: center;
  margin-right: 20px;
  color: white;
  font-size: 26px;
}

.element-text h3 {
  font-size: 18px;
  margin-bottom: 8px;
}

.element-text p {
  font-size: 15px;
  color: var(--gray);
  margin: 0;
}

@keyframes floatAnimation {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-20px); }
}

.metrics-section {
  display: flex;
  justify-content: space-around;
  margin-top: 100px;
  flex-wrap: wrap;
  gap: 50px;
}

.metric-item {
  text-align: center;
}

.metric-value {
  font-size: 3.5rem;
  font-weight: 900;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 12px;
  line-height: 1;
}

.metric-label {
  font-size: 1.1rem;
  color: var(--gray);
  font-weight: 600;
}

/* Features */
.features-section,
.pricing-section,
.faq-section {
  padding: 130px 0;
}

.section-header {
  text-align: center;
  margin-bottom: 90px;
}

.section-title {
  font-size: 3.5rem;
  margin-bottom: 28px;
  color: var(--dark);
}

.section-subtitle {
  font-size: 1.3rem;
  color: var(--gray);
  max-width: 760px;
  margin: 0 auto;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(380px, 100%), 1fr));
  gap: 45px;
}

.feature-card {
  background-color: white;
  border-radius: var(--border-radius);
  padding: 56px 46px;
  box-shadow: var(--shadow);
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.feature-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 6px;
  background: linear-gradient(to right, var(--primary), var(--secondary));
}

.feature-card:hover {
  transform: translateY(-12px);
  box-shadow: var(--shadow-hover);
}

.card-icon {
  width: 82px;
  height: 82px;
  border-radius: 22px;
  background: linear-gradient(135deg, rgba(110, 142, 251, 0.12), rgba(74, 222, 222, 0.12));
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 36px;
  color: var(--primary);
  font-size: 40px;
}

.feature-card h3 {
  font-size: 2rem;
  margin-bottom: 26px;
  color: var(--dark);
}

.feature-card p {
  color: var(--gray);
}

/* Download */
.download-section {
  padding: 110px 0;
  background-color: var(--light);
}

.download-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 70px;
}

.download-content {
  flex: 1;
}

.download-content h2 {
  font-size: 3.5rem;
  margin-bottom: 32px;
  color: var(--dark);
}

.download-content h2 span {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.download-content > p {
  font-size: 1.3rem;
  color: var(--gray);
  margin-bottom: 48px;
  max-width: 540px;
}

.platform-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
  margin-bottom: 48px;
  max-width: 540px;
}

.platform-item {
  display: flex;
  align-items: center;
  background-color: white;
  border-radius: var(--border-radius);
  padding: 30px;
  box-shadow: var(--shadow);
  transition: var(--transition);
  text-decoration: none;
  color: inherit;
}

.platform-item:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-hover);
}

.platform-item.windows { border-left: 6px solid var(--primary); }
.platform-item.macos { border-left: 6px solid #000000; }
.platform-item.android { border-left: 6px solid #3DDC84; }
.platform-item.ios { border-left: 6px solid #007AFF; }

.platform-icon {
  font-size: 42px;
  margin-right: 28px;
}

.platform-item.windows .platform-icon { color: var(--primary); }
.platform-item.macos .platform-icon { color: #000000; }
.platform-item.android .platform-icon { color: #3DDC84; }
.platform-item.ios .platform-icon { color: #007AFF; }

.platform-details h3,
.platform-details h4 {
  font-size: 1.3rem;
  margin-bottom: 10px;
}

.platform-details p {
  font-size: 1rem;
  color: var(--gray);
  margin: 0;
}

.download-visual {
  flex: 1;
  display: flex;
  justify-content: center;
}

.download-visual img {
  max-width: 100%;
  border-radius: var(--border-radius);
  box-shadow: 0 32px 64px rgba(0, 0, 0, 0.15);
  object-fit: cover;
  aspect-ratio: 718 / 607;
}

.hint {
  font-size: 1rem;
  color: var(--gray);
  margin-top: 28px;
  display: flex;
  align-items: center;
  gap: 8px;
}

/* Pricing */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.price-card {
  background: #fff;
  border-radius: var(--border-radius);
  padding: 48px 36px;
  box-shadow: var(--shadow);
  text-align: center;
  position: relative;
  transition: var(--transition);
}

.price-card:hover {
  transform: translateY(-10px);
  box-shadow: var(--shadow-hover);
}

.price-card.featured {
  border: 2px solid var(--primary);
  transform: scale(1.04);
}

.price-badge {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: #fff;
  font-size: 13px;
  font-weight: 700;
  padding: 6px 16px;
  border-radius: 999px;
}

.price-card h3 {
  font-size: 1.5rem;
  margin-bottom: 16px;
}

.price-amount {
  font-size: 2.6rem;
  font-weight: 900;
  margin-bottom: 8px;
}

.price-amount span {
  font-size: 1rem;
  font-weight: 600;
  color: var(--gray);
}

.price-card ul {
  list-style: none;
  text-align: left;
  margin: 28px 0 36px;
  color: var(--gray);
}

.price-card li {
  margin-bottom: 12px;
  padding-left: 8px;
}

/* FAQ */
.faq-wrapper {
  max-width: 960px;
  margin: 0 auto;
}

.faq-item {
  margin-bottom: 28px;
  border-radius: var(--border-radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: var(--transition);
  background: #fff;
}

.faq-item:hover {
  box-shadow: 0 20px 45px rgba(0, 0, 0, 0.1);
}

.faq-question {
  padding: 34px 38px;
  background-color: white;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-weight: 700;
  font-size: 1.2rem;
  width: 100%;
  border: 0;
  font-family: var(--font);
  text-align: left;
  color: var(--dark);
  gap: 16px;
}

.faq-question .icon {
  color: var(--primary);
  transition: var(--transition);
  font-size: 18px;
}

.faq-answer {
  padding: 0 38px;
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease, padding 0.35s ease;
  background-color: white;
}

.faq-answer p {
  padding: 0 0 22px;
  color: var(--gray);
}

.faq-item.active .faq-answer {
  max-height: 2200px;
  padding-bottom: 16px;
}

.faq-item.active .faq-question .icon {
  transform: rotate(180deg);
}

/* Footer */
.page-footer {
  background-color: var(--dark);
  color: white;
  padding: 110px 0 60px;
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 60px;
  margin-bottom: 80px;
}

.footer-logo {
  display: flex;
  align-items: center;
  font-size: 32px;
  font-weight: 900;
  color: white;
  margin-bottom: 32px;
  text-decoration: none;
  gap: 16px;
}

.footer-logo-icon {
  width: 56px;
  height: 56px;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 26px;
}

.footer-description {
  color: #A0AEC0;
  margin-bottom: 40px;
  line-height: 2;
}

.social-icons {
  display: flex;
  gap: 20px;
}

.social-icon {
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background-color: rgba(255, 255, 255, 0.12);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  text-decoration: none;
  transition: var(--transition);
  font-size: 18px;
}

.social-icon:hover {
  background-color: var(--primary);
  transform: translateY(-5px);
}

.footer-links h3,
.footer-contact h3 {
  font-size: 1.4rem;
  margin-bottom: 36px;
  position: relative;
  padding-bottom: 16px;
}

.footer-links h3::after,
.footer-contact h3::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 50px;
  height: 4px;
  background: linear-gradient(to right, var(--primary), var(--secondary));
}

.footer-links ul {
  list-style: none;
}

.footer-links li {
  margin-bottom: 20px;
}

.footer-links a {
  color: #A0AEC0;
  text-decoration: none;
  transition: var(--transition);
}

.footer-links a:hover {
  color: var(--primary);
  padding-left: 12px;
}

.footer-contact p {
  color: #A0AEC0;
  margin-bottom: 22px;
  display: flex;
  align-items: center;
  gap: 14px;
}

.footer-contact .icon {
  color: var(--primary);
  width: 20px;
}

.footer-bottom {
  text-align: center;
  padding-top: 60px;
  border-top: 1px solid #2D3748;
  color: #718096;
  font-size: 1rem;
}

.footer-bottom a {
  color: #A0AEC0;
  text-decoration: none;
}

.footer-bottom a:hover {
  color: #fff;
}

/* Mobile menu */
.mobile-menu {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: white;
  z-index: 9999;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  transform: translateX(100%);
  transition: transform 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.mobile-menu.active {
  transform: translateX(0);
}

.mobile-close {
  position: absolute;
  top: 40px;
  right: 40px;
  font-size: 32px;
  color: var(--dark);
  cursor: pointer;
  background: none;
  border: none;
}

.mobile-nav {
  list-style: none;
  text-align: center;
}

.mobile-nav li {
  margin-bottom: 45px;
}

.mobile-nav a {
  font-size: 2.1rem;
  font-weight: 800;
  color: var(--dark);
  text-decoration: none;
}

.mobile-nav a:hover,
.mobile-nav a.active {
  color: var(--primary);
}

.mobile-actions {
  margin-top: 60px;
  display: flex;
  flex-direction: column;
  gap: 24px;
}

/* Download page extras */
.page-hero {
  padding: 170px 0 70px;
  background: linear-gradient(135deg, #F0F5FF 0%, #E8EEFF 100%);
  text-align: center;
}

.breadcrumb {
  display: flex;
  justify-content: center;
  gap: 8px;
  color: var(--gray);
  font-size: 14px;
  margin-bottom: 24px;
}

.breadcrumb a {
  color: var(--primary);
  text-decoration: none;
}

.download-cards {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
  margin: 40px 0 80px;
}

.download-card {
  background: #fff;
  border-radius: var(--border-radius);
  padding: 40px 36px;
  box-shadow: var(--shadow);
}

.download-card h2 {
  font-size: 1.6rem;
  margin: 16px 0 10px;
}

.download-card p {
  color: var(--gray);
  margin-bottom: 24px;
}

.download-card .meta {
  font-size: 14px;
  color: var(--gray);
  margin-bottom: 20px;
}

.not-found {
  min-height: 70vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 160px 24px 80px;
}

.not-found h1 {
  font-size: 5rem;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(50px); }
  to { opacity: 1; transform: translateY(0); }
}

.animate-in {
  animation: fadeIn 0.9s ease forwards;
}

.delay-1 { animation-delay: 0.1s; }
.delay-2 { animation-delay: 0.2s; }
.delay-3 { animation-delay: 0.3s; }
.delay-4 { animation-delay: 0.4s; }

.scroll-animate {
  opacity: 0;
  transform: translateY(60px);
  transition: opacity 1s ease, transform 1s ease;
}

.scroll-animate.visible {
  opacity: 1;
  transform: translateY(0);
}

@media (max-width: 1200px) {
  .hero-container,
  .download-container {
    flex-direction: column;
    text-align: center;
  }

  .hero-visual,
  .download-visual {
    margin-top: 80px;
  }

  .hero-headline {
    font-size: 3.6rem;
  }

  .feature-highlights,
  .hero-cta {
    justify-content: center;
  }

  .section-title,
  .download-content h2 {
    font-size: 3rem;
  }

  .hint {
    justify-content: center;
  }
}

@media (max-width: 960px) {
  .pricing-grid,
  .download-cards {
    grid-template-columns: 1fr;
  }

  .price-card.featured {
    transform: none;
  }
}

@media (max-width: 850px) {
  .primary-navigation,
  .header-actions .action-button.outline {
    display: none;
  }

  .mobile-nav-toggle {
    display: block;
  }

  .hero-section {
    padding: 170px 0 90px;
  }

  .hero-headline {
    font-size: 3.2rem;
  }

  .hero-cta {
    flex-direction: column;
    align-items: center;
  }

  .action-button {
    width: 100%;
    max-width: 340px;
  }

  .features-grid,
  .platform-grid {
    grid-template-columns: 1fr;
  }

  .floating-element {
    display: none;
  }
}

@media (max-width: 550px) {
  .container {
    padding: 0 20px;
  }

  .hero-headline {
    font-size: 2.4rem;
  }

  .section-title,
  .download-content h2 {
    font-size: 2.2rem;
  }

  .feature-card {
    padding: 46px 28px;
  }

  .faq-question {
    padding: 28px 20px;
    font-size: 1.05rem;
  }

  .faq-answer {
    padding-left: 20px;
    padding-right: 20px;
  }

  .metric-value {
    font-size: 2.4rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *,
  *::before,
  *::after {
    animation: none !important;
    transition: none !important;
  }
}