/* ========== CSS Variables ========== */
:root {
  --tg-blue: #24A1DE;
  --tg-blue-dark: #1a8bc4;
  --tg-blue-light: #e8f5fc;
  --accent-green: #34b566;
  --accent-orange: #f5a623;
  --accent-purple: #8e6cd6;
  --text-primary: #1a1a1a;
  --text-secondary: #5a5a5a;
  --text-muted: #8a8a8a;
  --bg-white: #ffffff;
  --bg-light: #f5f7fa;
  --bg-dark: #0f1623;
  --bg-card: #ffffff;
  --border-light: #e4e8ee;
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.06);
  --shadow-md: 0 8px 30px rgba(0,0,0,0.08);
  --shadow-lg: 0 20px 60px rgba(0,0,0,0.12);
  --radius-sm: 8px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-xl: 32px;
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif;
  color: var(--text-primary);
  background: var(--bg-white);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  color: var(--tg-blue);
  text-decoration: none;
  transition: var(--transition);
}

a:hover {
  color: var(--tg-blue-dark);
}

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

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  outline: none;
}

ul, ol {
  list-style: none;
}

/* ========== Animations ========== */
@keyframes spin {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes slideInLeft {
  from {
    opacity: 0;
    transform: translateX(-40px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes slideInRight {
  from {
    opacity: 0;
    transform: translateX(40px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes pulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.05); }
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

@keyframes shimmer {
  0% { background-position: -200% 0; }
  100% { background-position: 200% 0; }
}

.animate-fadeInUp {
  animation: fadeInUp 0.7s ease-out forwards;
}

.animate-fadeIn {
  animation: fadeIn 0.5s ease-out forwards;
}

.animate-slideInLeft {
  animation: slideInLeft 0.7s ease-out forwards;
}

.animate-slideInRight {
  animation: slideInRight 0.7s ease-out forwards;
}

.delay-100 { animation-delay: 0.1s; }
.delay-200 { animation-delay: 0.2s; }
.delay-300 { animation-delay: 0.3s; }
.delay-400 { animation-delay: 0.4s; }
.delay-500 { animation-delay: 0.5s; }

/* ========== Container ========== */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ========== Navigation ========== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-light);
  transition: var(--transition);
}

.navbar-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.navbar-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
}

.navbar-logo svg {
  width: 36px;
  height: 36px;
  flex-shrink: 0;
}

.navbar-menu {
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 10px 20px;
  border-radius: 100px;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: var(--transition);
  white-space: nowrap;
}

.nav-item:hover {
  background: var(--bg-light);
  color: var(--text-primary);
}

.nav-item.active {
  background: var(--tg-blue);
  color: #fff;
}

.nav-item.active:hover {
  background: var(--tg-blue-dark);
  color: #fff;
}

.nav-item svg {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

/* Mobile menu toggle */
.menu-toggle {
  display: none;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
  background: var(--bg-light);
  align-items: center;
  justify-content: center;
}

/* ========== Buttons ========== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 28px;
  border-radius: 100px;
  font-size: 1rem;
  font-weight: 600;
  transition: var(--transition);
  white-space: nowrap;
}

.btn-primary {
  background: var(--tg-blue);
  color: #fff;
  box-shadow: 0 4px 16px rgba(36, 161, 222, 0.3);
}

.btn-primary:hover {
  background: var(--tg-blue-dark);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(36, 161, 222, 0.4);
}

.btn-primary:active {
  transform: translateY(0);
}

.btn-secondary {
  background: var(--bg-light);
  color: var(--text-primary);
  border: 1px solid var(--border-light);
}

.btn-secondary:hover {
  background: var(--border-light);
  transform: translateY(-2px);
}

.btn-large {
  padding: 16px 36px;
  font-size: 1.1rem;
}

.btn svg {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
}

/* ========== Hero Section ========== */
.hero {
  position: relative;
  padding: 140px 0 100px;
  background: linear-gradient(135deg, var(--bg-light) 0%, var(--bg-white) 50%, var(--tg-blue-light) 100%);
  overflow: hidden;
}

.hero-bg-pattern {
  position: absolute;
  inset: 0;
  opacity: 0.4;
  background-image: radial-gradient(circle at 20% 50%, rgba(36,161,222,0.08) 0%, transparent 50%),
                      radial-gradient(circle at 80% 80%, rgba(36,161,222,0.06) 0%, transparent 40%);
}

.hero-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
  position: relative;
  z-index: 1;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 18px;
  background: rgba(36, 161, 222, 0.1);
  color: var(--tg-blue);
  border-radius: 100px;
  font-size: 0.875rem;
  font-weight: 600;
  margin-bottom: 24px;
  animation: fadeInUp 0.5s ease-out;
}

.hero-badge svg {
  width: 16px;
  height: 16px;
}

.hero-title {
  font-size: 3rem;
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: 20px;
  letter-spacing: -0.02em;
}

.hero-title .highlight {
  background: linear-gradient(135deg, var(--tg-blue) 0%, var(--accent-purple) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-desc {
  font-size: 1.15rem;
  color: var(--text-secondary);
  margin-bottom: 32px;
  max-width: 480px;
  line-height: 1.7;
}

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

.hero-stats {
  display: flex;
  gap: 40px;
  margin-top: 40px;
  padding-top: 32px;
  border-top: 1px solid var(--border-light);
}

.hero-stat {
  text-align: left;
}

.hero-stat-num {
  font-size: 1.75rem;
  font-weight: 800;
  color: var(--tg-blue);
  line-height: 1;
}

.hero-stat-label {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-top: 6px;
}

.hero-visual {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
}

.hero-phone-mockup {
  width: 280px;
  height: 560px;
  background: var(--bg-dark);
  border-radius: 40px;
  padding: 12px;
  box-shadow: var(--shadow-lg), 0 0 0 1px rgba(0,0,0,0.1);
  animation: float 6s ease-in-out infinite;
}

.hero-phone-screen {
  width: 100%;
  height: 100%;
  background: linear-gradient(180deg, #1a2a4a 0%, #0f1623 100%);
  border-radius: 32px;
  overflow: hidden;
  position: relative;
  display: flex;
  flex-direction: column;
}

.phone-header {
  padding: 16px 20px;
  display: flex;
  align-items: center;
  gap: 12px;
  border-bottom: 1px solid rgba(255,255,255,0.06);
}

.phone-avatar {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--tg-blue) 0%, var(--accent-purple) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 0.75rem;
  font-weight: 700;
}

.phone-chat-info {
  flex: 1;
}

.phone-chat-name {
  color: #fff;
  font-size: 0.875rem;
  font-weight: 600;
}

.phone-chat-status {
  color: var(--accent-green);
  font-size: 0.75rem;
}

.phone-messages {
  flex: 1;
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.phone-msg {
  max-width: 80%;
  padding: 10px 14px;
  border-radius: 18px;
  font-size: 0.8rem;
  line-height: 1.4;
}

.phone-msg-in {
  background: rgba(255,255,255,0.08);
  color: #e0e0e0;
  align-self: flex-start;
  border-bottom-left-radius: 4px;
}

.phone-msg-out {
  background: var(--tg-blue);
  color: #fff;
  align-self: flex-end;
  border-bottom-right-radius: 4px;
}

.phone-input {
  padding: 12px 16px;
  display: flex;
  align-items: center;
  gap: 10px;
  border-top: 1px solid rgba(255,255,255,0.06);
}

.phone-input-bar {
  flex: 1;
  height: 36px;
  background: rgba(255,255,255,0.08);
  border-radius: 18px;
}

.phone-send-btn {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--tg-blue);
  display: flex;
  align-items: center;
  justify-content: center;
}

.hero-phone-mockup::before {
  content: '';
  position: absolute;
  top: -20px;
  right: -40px;
  width: 120px;
  height: 120px;
  background: var(--tg-blue);
  opacity: 0.15;
  border-radius: 50%;
  filter: blur(40px);
}

.hero-phone-mockup::after {
  content: '';
  position: absolute;
  bottom: 40px;
  left: -30px;
  width: 80px;
  height: 80px;
  background: var(--accent-purple);
  opacity: 0.12;
  border-radius: 50%;
  filter: blur(30px);
}

/* ========== Section Styles ========== */
.section {
  padding: 80px 0;
}

.section-header {
  text-align: center;
  max-width: 640px;
  margin: 0 auto 56px;
}

.section-label {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  background: var(--tg-blue-light);
  color: var(--tg-blue);
  border-radius: 100px;
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 16px;
}

.section-title {
  font-size: 2.25rem;
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 16px;
}

.section-desc {
  font-size: 1.05rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

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

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 36px 28px;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--tg-blue), var(--accent-purple));
  opacity: 0;
  transition: var(--transition);
}

.feature-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
  border-color: transparent;
}

.feature-card:hover::before {
  opacity: 1;
}

.feature-icon {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
}

.feature-icon.blue { background: var(--tg-blue-light); color: var(--tg-blue); }
.feature-icon.green { background: rgba(52,181,102,0.1); color: var(--accent-green); }
.feature-icon.orange { background: rgba(245,166,35,0.1); color: var(--accent-orange); }
.feature-icon.purple { background: rgba(142,108,214,0.1); color: var(--accent-purple); }

.feature-icon svg {
  width: 28px;
  height: 28px;
}

.feature-title {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 10px;
}

.feature-desc {
  font-size: 0.925rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ========== Platform Download Cards ========== */
.platforms-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.platform-card {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 32px 24px;
  text-align: center;
  transition: var(--transition);
}

.platform-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--tg-blue);
}

.platform-icon {
  width: 64px;
  height: 64px;
  margin: 0 auto 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  background: var(--bg-light);
}

.platform-icon svg {
  width: 36px;
  height: 36px;
}

.platform-name {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 6px;
}

.platform-version {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-bottom: 20px;
}

.platform-card .btn {
  width: 100%;
  padding: 12px 20px;
  font-size: 0.9rem;
}

/* ========== Download Page - Hero Variant ========== */
.download-hero {
  background: linear-gradient(135deg, var(--bg-dark) 0%, #1a2a4a 100%);
  color: #fff;
  padding: 140px 0 80px;
}

.download-hero .hero-title,
.download-hero .hero-desc {
  color: #fff;
}

.download-hero .hero-desc {
  opacity: 0.8;
}

.download-hero .section-title {
  color: #fff;
}

.download-hero .section-desc {
  color: rgba(255,255,255,0.7);
}

/* Windows highlight card */
.windows-highlight {
  background: linear-gradient(135deg, #1e3a5f 0%, #0f1623 100%);
  border: 1px solid rgba(36, 161, 222, 0.3);
  border-radius: var(--radius-lg);
  padding: 48px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
  margin-bottom: 40px;
  position: relative;
  overflow: hidden;
}

.windows-highlight::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, rgba(36,161,222,0.15) 0%, transparent 70%);
}

.windows-info {
  position: relative;
  z-index: 1;
}

.windows-label {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  background: rgba(36, 161, 222, 0.2);
  color: var(--tg-blue);
  border-radius: 100px;
  font-size: 0.8rem;
  font-weight: 700;
  margin-bottom: 16px;
}

.windows-title {
  font-size: 2rem;
  font-weight: 800;
  margin-bottom: 12px;
  color: #fff;
}

.windows-desc {
  color: rgba(255,255,255,0.7);
  margin-bottom: 24px;
  line-height: 1.7;
}

.windows-meta {
  display: flex;
  gap: 24px;
  margin-bottom: 28px;
}

.windows-meta-item {
  display: flex;
  align-items: center;
  gap: 8px;
  color: rgba(255,255,255,0.6);
  font-size: 0.875rem;
}

.windows-meta-item svg {
  width: 18px;
  height: 18px;
  color: var(--tg-blue);
}

.windows-visual {
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  z-index: 1;
}

.windows-logo-wrap {
  width: 160px;
  height: 160px;
  background: rgba(36, 161, 222, 0.1);
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid rgba(36, 161, 222, 0.2);
}

.windows-logo-wrap svg {
  width: 80px;
  height: 80px;
  color: var(--tg-blue);
}

/* ========== Testimonials ========== */
.testimonials-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.testimonial-card {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 32px;
  transition: var(--transition);
}

.testimonial-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-3px);
}

.testimonial-stars {
  display: flex;
  gap: 4px;
  margin-bottom: 16px;
}

.testimonial-stars svg {
  width: 18px;
  height: 18px;
  color: var(--accent-orange);
}

.testimonial-text {
  font-size: 1rem;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 20px;
}

.testimonial-author {
  display: flex;
  align-items: center;
  gap: 12px;
}

.testimonial-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--tg-blue) 0%, var(--accent-purple) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-weight: 700;
  font-size: 0.875rem;
}

.testimonial-name {
  font-weight: 700;
  font-size: 0.95rem;
}

.testimonial-role {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* ========== FAQ ========== */
.faq-list {
  max-width: 800px;
  margin: 0 auto;
}

.faq-item {
  border-bottom: 1px solid var(--border-light);
  overflow: hidden;
}

.faq-question {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 24px 0;
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text-primary);
  background: none;
  text-align: left;
  transition: var(--transition);
}

.faq-question:hover {
  color: var(--tg-blue);
}

.faq-question svg {
  width: 22px;
  height: 22px;
  color: var(--text-muted);
  transition: var(--transition);
  flex-shrink: 0;
  margin-left: 16px;
}

.faq-item.active .faq-question svg {
  transform: rotate(180deg);
  color: var(--tg-blue);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease-out, padding 0.4s ease-out;
}

.faq-item.active .faq-answer {
  max-height: 500px;
  padding-bottom: 24px;
}

.faq-answer p {
  color: var(--text-secondary);
  line-height: 1.7;
  font-size: 0.95rem;
}

/* ========== SEO Page Styles ========== */
.seo-content {
  max-width: 860px;
  margin: 0 auto;
}

.seo-article h2 {
  font-size: 1.6rem;
  font-weight: 700;
  margin: 48px 0 20px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--border-light);
}

.seo-article h3 {
  font-size: 1.25rem;
  font-weight: 700;
  margin: 32px 0 14px;
  color: var(--tg-blue-dark);
}

.seo-article p {
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 16px;
  font-size: 1rem;
}

.seo-article ul, .seo-article ol {
  margin: 16px 0 20px 24px;
  color: var(--text-secondary);
  line-height: 1.8;
}

.seo-article ul li {
  list-style-type: disc;
  margin-bottom: 8px;
}

.seo-article ol li {
  list-style-type: decimal;
  margin-bottom: 8px;
}

.seo-article strong {
  color: var(--text-primary);
  font-weight: 600;
}

.comparison-table {
  width: 100%;
  border-collapse: collapse;
  margin: 24px 0;
  font-size: 0.925rem;
}

.comparison-table th,
.comparison-table td {
  padding: 14px 16px;
  text-align: left;
  border-bottom: 1px solid var(--border-light);
}

.comparison-table th {
  font-weight: 700;
  background: var(--bg-light);
  color: var(--text-primary);
}

.comparison-table td {
  color: var(--text-secondary);
}

.comparison-table tr:hover td {
  background: rgba(36, 161, 222, 0.03);
}

.comparison-table .check {
  color: var(--accent-green);
  font-weight: 700;
}

.comparison-table .cross {
  color: #e74c3c;
  font-weight: 700;
}

.cta-box {
  background: linear-gradient(135deg, var(--tg-blue-light) 0%, rgba(142,108,214,0.08) 100%);
  border: 2px solid var(--tg-blue);
  border-radius: var(--radius-lg);
  padding: 40px;
  text-align: center;
  margin: 48px 0;
}

.cta-box-title {
  font-size: 1.5rem;
  font-weight: 800;
  margin-bottom: 12px;
}

.cta-box-desc {
  color: var(--text-secondary);
  margin-bottom: 24px;
  font-size: 1.05rem;
}

/* ========== Version History ========== */
.version-timeline {
  position: relative;
  padding-left: 32px;
}

.version-timeline::before {
  content: '';
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: var(--border-light);
}

.version-item {
  position: relative;
  margin-bottom: 28px;
}

.version-item::before {
  content: '';
  position: absolute;
  left: -28px;
  top: 6px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--tg-blue);
  border: 3px solid var(--bg-white);
  box-shadow: 0 0 0 2px var(--tg-blue);
}

.version-item.latest::before {
  background: var(--accent-green);
  box-shadow: 0 0 0 2px var(--accent-green);
}

.version-tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  background: var(--tg-blue-light);
  color: var(--tg-blue);
  border-radius: 100px;
  font-size: 0.8rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.version-tag.latest {
  background: rgba(52,181,102,0.1);
  color: var(--accent-green);
}

.version-date {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-bottom: 6px;
}

.version-desc {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.6;
}

/* ========== Tips Grid ========== */
.tips-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
  margin-top: 20px;
}

.tip-card {
  background: var(--bg-light);
  border-radius: var(--radius-md);
  padding: 24px;
  display: flex;
  gap: 16px;
  align-items: flex-start;
  transition: var(--transition);
}

.tip-card:hover {
  background: var(--tg-blue-light);
  transform: translateX(4px);
}

.tip-num {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--tg-blue);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.875rem;
  font-weight: 700;
  flex-shrink: 0;
}

.tip-content h4 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 6px;
}

.tip-content p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin: 0;
}

/* ========== Footer ========== */
.footer {
  background: var(--bg-dark);
  color: rgba(255,255,255,0.7);
  padding: 60px 0 32px;
}

.footer-top {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 48px;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.15rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: 16px;
}

.footer-brand svg {
  width: 32px;
  height: 32px;
}

.footer-desc {
  font-size: 0.9rem;
  line-height: 1.7;
  color: rgba(255,255,255,0.5);
  margin-bottom: 20px;
}

.footer-social {
  display: flex;
  gap: 12px;
}

.footer-social a {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: rgba(255,255,255,0.08);
  display: flex;
  align-items: center;
  justify-content: center;
  color: rgba(255,255,255,0.6);
  transition: var(--transition);
}

.footer-social a:hover {
  background: var(--tg-blue);
  color: #fff;
  transform: translateY(-2px);
}

.footer-social svg {
  width: 18px;
  height: 18px;
}

.footer-title {
  font-size: 0.9rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: 20px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.footer-links li {
  margin-bottom: 12px;
}

.footer-links a {
  color: rgba(255,255,255,0.5);
  font-size: 0.9rem;
  transition: var(--transition);
}

.footer-links a:hover {
  color: var(--tg-blue);
}

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.08);
  padding-top: 24px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-verify {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.875rem;
  color: var(--accent-green);
}

.footer-verify svg {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

.footer-copyright {
  font-size: 0.8rem;
  color: rgba(255,255,255,0.4);
  line-height: 1.6;
}

/* ========== Dark Section ========== */
.dark-section {
  background: var(--bg-dark);
  color: #fff;
}

.dark-section .section-title {
  color: #fff;
}

.dark-section .section-desc {
  color: rgba(255,255,255,0.6);
}

/* ========== Responsive ========== */
@media (max-width: 1024px) {
  .hero-inner {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .hero-title {
    font-size: 2.5rem;
  }

  .hero-desc {
    margin-left: auto;
    margin-right: auto;
  }

  .hero-actions {
    justify-content: center;
  }

  .hero-stats {
    justify-content: center;
  }

  .hero-visual {
    order: -1;
  }

  .hero-phone-mockup {
    width: 240px;
    height: 480px;
  }

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

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

  .footer-top {
    grid-template-columns: 1fr 1fr;
  }

  .windows-highlight {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .windows-meta {
    justify-content: center;
  }
}

@media (max-width: 768px) {
  .navbar-menu {
    display: none;
    position: absolute;
    top: 72px;
    left: 0;
    right: 0;
    background: rgba(255,255,255,0.98);
    backdrop-filter: blur(20px);
    flex-direction: column;
    padding: 16px 24px;
    gap: 8px;
    border-bottom: 1px solid var(--border-light);
    box-shadow: var(--shadow-md);
  }

  .navbar-menu.open {
    display: flex;
  }

  .nav-item {
    width: 100%;
    justify-content: center;
  }

  .menu-toggle {
    display: flex;
  }

  .hero {
    padding: 120px 0 60px;
  }

  .hero-title {
    font-size: 2rem;
  }

  .hero-stats {
    flex-direction: column;
    gap: 20px;
    align-items: center;
  }

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

  .section {
    padding: 60px 0;
  }

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

  .footer-top {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .tips-grid {
    grid-template-columns: 1fr;
  }

  .comparison-table {
    font-size: 0.8rem;
  }

  .comparison-table th,
  .comparison-table td {
    padding: 10px 8px;
  }

  .cta-box {
    padding: 28px 20px;
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 1.6rem;
  }

  .btn-large {
    padding: 14px 24px;
    font-size: 1rem;
  }

  .windows-highlight {
    padding: 32px 24px;
  }
}