/* ========================================
   VideoStreamPerf - 清新简洁宣传网页样式
   ======================================== */

/* ---------- Reset & Base ---------- */
*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 72px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text",
    "Helvetica Neue", Arial, sans-serif;
  color: #1d1d1f;
  background: #ffffff;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

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

/* ---------- Utility ---------- */
.container {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 100px 0;
}

.section-title {
  font-size: 2.25rem;
  font-weight: 700;
  text-align: center;
  margin-bottom: 12px;
  letter-spacing: -0.02em;
  color: #1d1d1f;
}

.section-desc {
  font-size: 1.125rem;
  text-align: center;
  color: #6e6e73;
  margin-bottom: 56px;
  max-width: 560px;
  margin-left: auto;
  margin-right: auto;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 14px 32px;
  border-radius: 12px;
  font-size: 1rem;
  font-weight: 600;
  transition: all 0.3s ease;
  cursor: pointer;
  border: none;
}

.btn-primary {
  background: #007aff;
  color: #ffffff;
  box-shadow: 0 4px 14px rgba(0, 122, 255, 0.25);
}

.btn-primary:hover {
  background: #0066d6;
  box-shadow: 0 6px 20px rgba(0, 122, 255, 0.35);
  transform: translateY(-1px);
}

.btn-secondary {
  background: #f5f5f7;
  color: #1d1d1f;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
}

.btn-secondary:hover {
  background: #e8e8ed;
  transform: translateY(-1px);
}

.btn-lg {
  padding: 18px 40px;
  font-size: 1.125rem;
  border-radius: 14px;
}

.apple-icon {
  flex-shrink: 0;
}

/* ---------- Navbar ---------- */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.72);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid rgba(0, 0, 0, 0.06);
  transition: background 0.3s ease;
}

.navbar.scrolled {
  background: rgba(255, 255, 255, 0.92);
  box-shadow: 0 1px 12px rgba(0, 0, 0, 0.06);
}

.nav-container {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.nav-brand {
  font-size: 1.25rem;
  font-weight: 700;
  color: #1d1d1f;
  display: flex;
  align-items: center;
  gap: 6px;
}

.brand-icon {
  color: #007aff;
  font-size: 0.875rem;
}

.nav-links {
  list-style: none;
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-links a {
  padding: 8px 16px;
  font-size: 0.9375rem;
  font-weight: 500;
  color: #6e6e73;
  border-radius: 8px;
  transition: all 0.2s ease;
}

.nav-links a:hover {
  color: #1d1d1f;
  background: rgba(0, 0, 0, 0.04);
}

.nav-links a.active {
  color: #007aff;
}

.nav-cta {
  background: #007aff !important;
  color: #ffffff !important;
  border-radius: 20px !important;
  padding: 8px 20px !important;
}

.nav-cta:hover {
  background: #0066d6 !important;
}

.nav-privacy {
  background: rgba(0, 0, 0, 0.04) !important;
  border: 1px solid rgba(0, 0, 0, 0.08) !important;
  border-radius: 20px !important;
  padding: 8px 18px !important;
  color: #424245 !important;
}

.nav-privacy:hover {
  background: rgba(0, 0, 0, 0.08) !important;
  color: #1d1d1f !important;
}

/* Nav right area */
.nav-right {
  display: flex;
  align-items: center;
  gap: 12px;
}

/* Language toggle */
.lang-toggle {
  display: flex;
  align-items: center;
  gap: 6px;
  background: rgba(0, 0, 0, 0.04);
  border: 1px solid rgba(0, 0, 0, 0.06);
  border-radius: 20px;
  padding: 6px 14px;
  cursor: pointer;
  font-size: 0.8125rem;
  font-weight: 500;
  color: #6e6e73;
  transition: all 0.2s ease;
  font-family: inherit;
  white-space: nowrap;
}

.lang-toggle:hover {
  background: rgba(0, 0, 0, 0.08);
  color: #1d1d1f;
}

.lang-label {
  line-height: 1;
}

/* Mobile toggle */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: #1d1d1f;
  border-radius: 2px;
  transition: all 0.3s ease;
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  overflow: hidden;
  padding-top: 64px;
}

.hero-bg {
  position: absolute;
  inset: 0;
  z-index: -1;
  background: linear-gradient(160deg, #f0f6ff 0%, #ffffff 40%, #f0fdf4 70%, #fefce8 100%);
}

.hero-bg::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -30%;
  width: 80%;
  height: 80%;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(0, 122, 255, 0.06) 0%, transparent 70%);
}

.hero-bg::after {
  content: '';
  position: absolute;
  bottom: -30%;
  left: -20%;
  width: 60%;
  height: 60%;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(52, 199, 89, 0.05) 0%, transparent 70%);
}

.hero-content {
  position: relative;
  z-index: 1;
  padding: 0 24px;
}

.hero-title {
  font-size: 4.5rem;
  font-weight: 800;
  letter-spacing: -0.04em;
  margin-bottom: 16px;
  background: linear-gradient(135deg, #1d1d1f 0%, #007aff 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: 1.5rem;
  font-weight: 500;
  color: #6e6e73;
  margin-bottom: 20px;
}

.hero-desc {
  font-size: 1.125rem;
  color: #86868b;
  line-height: 1.75;
  margin-bottom: 40px;
}

/* ---------- Features ---------- */
.features {
  background: #f5f5f7;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.feature-card {
  background: #ffffff;
  border-radius: 20px;
  padding: 36px 28px;
  text-align: center;
  transition: all 0.3s ease;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.04);
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.08);
}

.feature-icon {
  width: 64px;
  height: 64px;
  margin: 0 auto 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 16px;
  background: linear-gradient(135deg, #e8f2ff 0%, #f0f6ff 100%);
  color: #007aff;
}

.feature-card:nth-child(2) .feature-icon {
  background: linear-gradient(135deg, #e5f9ed 0%, #f0fdf4 100%);
  color: #34c759;
}

.feature-card:nth-child(3) .feature-icon {
  background: linear-gradient(135deg, #fff4e5 0%, #fffbf0 100%);
  color: #ff9500;
}

.feature-card:nth-child(4) .feature-icon {
  background: linear-gradient(135deg, #fce5f0 0%, #fef0f6 100%);
  color: #ff2d55;
}

.feature-card h3 {
  font-size: 1.125rem;
  font-weight: 650;
  margin-bottom: 10px;
  color: #1d1d1f;
}

.feature-card p {
  font-size: 0.9375rem;
  color: #6e6e73;
  line-height: 1.6;
}

/* ---------- Screenshots ---------- */
.screenshots-gallery {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.screenshot-item {
  position: relative;
  border-radius: 16px;
  overflow: hidden;
  cursor: pointer;
  background: #f5f5f7;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.06);
  transition: all 0.3s ease;
}

.screenshot-item:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.1);
}

.screenshot-item img {
  width: 100%;
  height: auto;
  display: block;
  transition: transform 0.3s ease;
}

.screenshot-item:hover img {
  transform: scale(1.02);
}

.screenshot-label {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 24px 16px 14px;
  background: linear-gradient(to top, rgba(0, 0, 0, 0.5), transparent);
  color: #ffffff;
  font-size: 0.875rem;
  font-weight: 500;
}

/* Span first 2 items larger */
.screenshots-gallery .screenshot-item:nth-child(1) {
  grid-column: span 2;
}

/* ---------- Video ---------- */
.video-section {
  background: #f5f5f7;
}

.video-wrapper {
  max-width: 900px;
  margin: 0 auto;
  border-radius: 20px;
  overflow: hidden;
  box-shadow: 0 8px 40px rgba(0, 0, 0, 0.1);
  background: #000;
}

.video-wrapper video {
  width: 100%;
  display: block;
}

/* ---------- Report ---------- */
.report-wrapper {
  max-width: 900px;
  margin: 0 auto 32px;
  border-radius: 16px;
  overflow: hidden;
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.08);
  background: #f5f5f7;
}

.report-wrapper iframe {
  width: 100%;
  height: 600px;
  border: none;
}

.report-actions {
  text-align: center;
}

/* ---------- Download CTA ---------- */
.download-section {
  background: linear-gradient(160deg, #f0f6ff 0%, #ffffff 50%, #f0fdf4 100%);
}

.download-content {
  text-align: center;
  max-width: 560px;
  margin: 0 auto;
}

.download-content h2 {
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.download-content p {
  font-size: 1.125rem;
  color: #6e6e73;
  margin-bottom: 36px;
}

/* ---------- Footer ---------- */
.footer {
  padding: 32px 0;
  text-align: center;
  color: #86868b;
  font-size: 0.875rem;
  border-top: 1px solid #e8e8ed;
}

.footer-line {
  margin-bottom: 0;
}

/* ---------- Lightbox ---------- */
.lightbox {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 2000;
  background: rgba(0, 0, 0, 0.85);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  align-items: center;
  justify-content: center;
}

.lightbox.active {
  display: flex;
}

.lightbox-content {
  max-width: 90vw;
  max-height: 90vh;
}

.lightbox-content img {
  max-width: 90vw;
  max-height: 85vh;
  object-fit: contain;
  border-radius: 12px;
  box-shadow: 0 16px 64px rgba(0, 0, 0, 0.3);
}

.lightbox-close {
  position: absolute;
  top: 20px;
  right: 24px;
  background: none;
  border: none;
  color: #ffffff;
  font-size: 2.5rem;
  cursor: pointer;
  opacity: 0.8;
  transition: opacity 0.2s ease;
  line-height: 1;
  z-index: 10;
}

.lightbox-close:hover {
  opacity: 1;
}

.lightbox-prev,
.lightbox-next {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  background: rgba(255, 255, 255, 0.15);
  border: none;
  color: #ffffff;
  font-size: 1.5rem;
  cursor: pointer;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.2s ease;
  z-index: 10;
}

.lightbox-prev:hover,
.lightbox-next:hover {
  background: rgba(255, 255, 255, 0.3);
}

.lightbox-prev {
  left: 20px;
}

.lightbox-next {
  right: 20px;
}

/* ---------- Fade-in Animation ---------- */
.fade-in {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- Responsive ---------- */
@media (max-width: 1024px) {
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .section {
    padding: 72px 0;
  }

  .section-title {
    font-size: 1.75rem;
  }

  .section-desc {
    font-size: 1rem;
    margin-bottom: 40px;
  }

  /* Navbar mobile */
  .nav-toggle {
    display: flex;
  }

  .nav-links {
    display: none;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.96);
    backdrop-filter: saturate(180%) blur(20px);
    -webkit-backdrop-filter: saturate(180%) blur(20px);
    flex-direction: column;
    padding: 16px 24px;
    gap: 4px;
    border-bottom: 1px solid rgba(0, 0, 0, 0.06);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
  }

  .nav-links.open {
    display: flex;
  }

  .nav-links a {
    padding: 12px 16px;
    width: 100%;
  }

  .nav-cta {
    text-align: center;
    border-radius: 12px !important;
    margin-top: 8px;
  }

  /* Hero mobile */
  .hero-title {
    font-size: 2.75rem;
  }

  .hero-subtitle {
    font-size: 1.25rem;
  }

  .hero-desc {
    font-size: 1rem;
  }

  /* Features mobile */
  .features-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  /* Screenshots mobile */
  .screenshots-gallery {
    grid-template-columns: 1fr;
  }

  .screenshots-gallery .screenshot-item:nth-child(1) {
    grid-column: span 1;
  }

  /* Video mobile */
  .video-wrapper {
    border-radius: 12px;
  }

  /* Report mobile */
  .report-wrapper iframe {
    height: 400px;
  }

  /* Download mobile */
  .download-content h2 {
    font-size: 2rem;
  }

  /* Lightbox mobile */
  .lightbox-prev {
    left: 8px;
  }

  .lightbox-next {
    right: 8px;
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 2.25rem;
  }

  .btn {
    padding: 12px 24px;
    font-size: 0.9375rem;
  }

  .btn-lg {
    padding: 14px 32px;
    font-size: 1rem;
  }
}

/* ---------- Privacy policy page (aligned with landing) ---------- */
body.privacy-page {
  padding-top: 0;
}

.privacy-page .nav-current {
  padding: 8px 16px;
  font-size: 0.9375rem;
  font-weight: 600;
  color: #007aff;
}

.privacy-hero {
  position: relative;
  text-align: center;
  padding: 104px 24px 56px;
  overflow: hidden;
}

.privacy-hero-inner {
  position: relative;
  z-index: 1;
  max-width: 640px;
  margin: 0 auto;
}

.privacy-hero-title {
  font-size: clamp(2.25rem, 5.5vw, 3.5rem);
  font-weight: 800;
  letter-spacing: -0.04em;
  margin-bottom: 12px;
  background: linear-gradient(135deg, #1d1d1f 0%, #007aff 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.privacy-hero-subtitle {
  font-size: 1.25rem;
  font-weight: 500;
  color: #6e6e73;
  margin-bottom: 10px;
  line-height: 1.45;
}

.privacy-hero-updated {
  font-size: 0.9375rem;
  color: #86868b;
  margin-bottom: 28px;
}

.privacy-hero-cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 32px;
  border-radius: 12px;
  font-size: 1rem;
  font-weight: 600;
  color: #ffffff;
  background: #007aff;
  box-shadow: 0 4px 14px rgba(0, 122, 255, 0.25);
  transition: all 0.3s ease;
}

.privacy-hero-cta:hover {
  background: #0066d6;
  box-shadow: 0 6px 20px rgba(0, 122, 255, 0.35);
  transform: translateY(-1px);
}

.privacy-body {
  background: #f5f5f7;
  padding: 40px 0 88px;
}

.privacy-stack {
  max-width: 800px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 28px;
}

.privacy-card {
  scroll-margin-top: 88px;
  background: #ffffff;
  border-radius: 20px;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.04);
  border: 1px solid rgba(0, 0, 0, 0.05);
  overflow: hidden;
  transition: box-shadow 0.3s ease;
}

.privacy-card:hover {
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.08);
}

.privacy-card-head {
  padding: 24px 28px 0;
}

.privacy-badge {
  display: inline-flex;
  align-items: center;
  padding: 6px 14px;
  font-size: 0.6875rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: #007aff;
  background: linear-gradient(135deg, #e8f2ff 0%, #f0f6ff 100%);
  border-radius: 100px;
}

.privacy-badge-zh {
  color: #1a7f37;
  background: linear-gradient(135deg, #e5f9ed 0%, #f0fdf4 100%);
}

.privacy-card-body {
  padding: 12px 32px 40px;
}

.privacy-card-body > p:first-of-type {
  margin-top: 4px;
}

.privacy-zh-title {
  font-size: 1.75rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: #1d1d1f;
  margin: 8px 0 6px;
  padding: 0;
  border: none;
}

.privacy-card-body .privacy-updated {
  font-size: 0.9375rem;
  color: #6e6e73;
  margin-bottom: 20px;
}

.privacy-card-body h2:not(.privacy-zh-title) {
  font-size: 1.125rem;
  font-weight: 650;
  margin: 26px 0 10px;
  color: #1d1d1f;
  padding-left: 14px;
  border-left: 3px solid #007aff;
}

.privacy-card-zh .privacy-card-body h2:not(.privacy-zh-title) {
  border-left-color: #34c759;
}

.privacy-card-body p,
.privacy-card-body li {
  font-size: 1rem;
  color: #424245;
  line-height: 1.7;
}

.privacy-card-body p {
  margin-bottom: 14px;
}

.privacy-card-body ul {
  margin: 0 0 14px 1.25rem;
}

.privacy-card-body li {
  margin-bottom: 8px;
}

.privacy-card-body a {
  color: #007aff;
  font-weight: 500;
  text-decoration: none;
}

.privacy-card-body a:hover {
  color: #0066d6;
  text-decoration: underline;
}

@media (max-width: 768px) {
  .privacy-hero {
    padding: 88px 20px 44px;
  }

  .privacy-hero-subtitle {
    font-size: 1.0625rem;
  }

  .privacy-body {
    padding: 28px 0 72px;
  }

  .privacy-card-head {
    padding: 20px 20px 0;
  }

  .privacy-card-body {
    padding: 10px 20px 32px;
  }

  .privacy-zh-title {
    font-size: 1.5rem;
  }
}