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

:root {
  --primary: #e05a33;
  --primary-dark: #c04a28;
  --primary-light: #f07a55;
  --secondary: #2c3e50;
  --accent: #3498db;
  --bg: #f8f9fa;
  --bg-white: #ffffff;
  --text: #333333;
  --text-light: #666666;
  --text-muted: #999999;
  --border: #e0e0e0;
  --shadow: 0 2px 12px rgba(0,0,0,0.08);
  --shadow-lg: 0 8px 30px rgba(0,0,0,0.12);
  --radius: 8px;
  --radius-lg: 12px;
  --transition: 0.3s ease;
}

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  font-size: 16px;
}

a { color: var(--primary); text-decoration: none; transition: var(--transition); }
a:hover { color: var(--primary-dark); }

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

ul { list-style: none; }

.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }

/* ========== Header ========== */
.site-header {
  background: var(--bg-white);
  box-shadow: 0 1px 4px rgba(0,0,0,0.06);
  position: sticky;
  top: 0;
  z-index: 1000;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 20px;
  max-width: 1200px;
  margin: 0 auto;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 22px;
  font-weight: 700;
  color: var(--secondary);
  text-decoration: none;
}

.logo:hover { color: var(--primary); }

.logo img { width: 40px; height: 40px; border-radius: 8px; }

.main-nav { display: flex; gap: 4px; }

.main-nav a {
  display: block;
  padding: 8px 18px;
  border-radius: 6px;
  color: var(--text);
  font-weight: 500;
  font-size: 15px;
  transition: var(--transition);
}

.main-nav a:hover,
.main-nav a.active {
  background: var(--primary);
  color: #fff;
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  font-size: 28px;
  color: var(--text);
  cursor: pointer;
  padding: 4px 8px;
}

/* ========== Hero Section ========== */
.hero {
  background: linear-gradient(135deg, #e05a33 0%, #c0392b 40%, #2c3e50 100%);
  color: #fff;
  padding: 80px 0 70px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle at 70% 30%, rgba(255,255,255,0.08) 0%, transparent 50%);
}

.hero .container { position: relative; z-index: 1; }

.hero-logo { width: 100px; height: 100px; margin: 0 auto 20px; border-radius: 20px; box-shadow: 0 4px 20px rgba(0,0,0,0.3); }

.hero h1 { font-size: 42px; font-weight: 800; margin-bottom: 16px; letter-spacing: -1px; }

.hero .subtitle {
  font-size: 20px;
  opacity: 0.9;
  margin-bottom: 30px;
  max-width: 700px;
  margin-left: auto;
  margin-right: auto;
}

.hero-buttons { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }

.btn {
  display: inline-block;
  padding: 12px 30px;
  border-radius: 30px;
  font-weight: 600;
  font-size: 16px;
  cursor: pointer;
  transition: var(--transition);
  border: none;
  text-decoration: none;
}

.btn-primary { background: #fff; color: var(--primary); }
.btn-primary:hover { background: #f0f0f0; color: var(--primary-dark); transform: translateY(-2px); box-shadow: 0 6px 20px rgba(0,0,0,0.2); }

.btn-secondary {
  background: transparent;
  color: #fff;
  border: 2px solid rgba(255,255,255,0.5);
}
.btn-secondary:hover { background: rgba(255,255,255,0.1); border-color: #fff; transform: translateY(-2px); }

.btn-outline {
  background: transparent;
  color: var(--primary);
  border: 2px solid var(--primary);
}
.btn-outline:hover { background: var(--primary); color: #fff; }

.btn-lg { padding: 14px 40px; font-size: 17px; }

/* ========== Stats Bar ========== */
.stats-bar {
  background: var(--bg-white);
  padding: 30px 0;
  border-bottom: 1px solid var(--border);
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 30px;
  text-align: center;
}

.stat-item .stat-number { font-size: 32px; font-weight: 800; color: var(--primary); }
.stat-item .stat-label { font-size: 14px; color: var(--text-light); margin-top: 4px; }

/* ========== Section Common ========== */
.section {
  padding: 70px 0;
}

.section-gray { background: var(--bg-white); }

.section-title {
  font-size: 32px;
  font-weight: 700;
  text-align: center;
  color: var(--secondary);
  margin-bottom: 12px;
}

.section-desc {
  text-align: center;
  color: var(--text-light);
  font-size: 16px;
  max-width: 700px;
  margin: 0 auto 50px;
}

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

.feature-card {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  padding: 30px 24px;
  box-shadow: var(--shadow);
  transition: var(--transition);
  border: 1px solid transparent;
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary-light);
}

.feature-icon {
  width: 56px;
  height: 56px;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 28px;
  color: #fff;
  margin-bottom: 18px;
}

.feature-card h3 { font-size: 18px; margin-bottom: 10px; color: var(--secondary); }
.feature-card p { color: var(--text-light); font-size: 14px; line-height: 1.8; }

/* ========== Feature List (2 col) ========== */
.feature-list-2col {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 30px;
}

.feature-item {
  display: flex;
  gap: 16px;
  align-items: flex-start;
  padding: 20px;
  background: var(--bg-white);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.feature-item .fi-icon {
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  background: rgba(224,90,51,0.1);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
}

.feature-item h4 { font-size: 16px; color: var(--secondary); margin-bottom: 4px; }
.feature-item p { font-size: 13px; color: var(--text-light); }

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

.screenshot-card {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: var(--transition);
}

.screenshot-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.screenshot-card img {
  width: 100%;
  height: 200px;
  object-fit: cover;
}

.screenshot-card .sc-caption {
  padding: 12px 16px;
  font-size: 14px;
  color: var(--text);
  font-weight: 500;
}

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

.platform-card {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  padding: 36px 24px;
  text-align: center;
  box-shadow: var(--shadow);
  transition: var(--transition);
  border-top: 4px solid transparent;
}

.platform-card:hover { border-top-color: var(--primary); transform: translateY(-4px); }

.platform-card .platform-icon { font-size: 56px; margin-bottom: 16px; }
.platform-card h3 { font-size: 20px; color: var(--secondary); margin-bottom: 10px; }
.platform-card p { color: var(--text-light); font-size: 14px; margin-bottom: 16px; }
.platform-card .platform-ver { font-size: 13px; color: var(--text-muted); margin-bottom: 16px; }

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

.step-card {
  text-align: center;
  padding: 30px 20px;
  position: relative;
}

.step-number {
  width: 60px;
  height: 60px;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
  font-weight: 800;
  margin: 0 auto 20px;
}

.step-card h3 { font-size: 18px; color: var(--secondary); margin-bottom: 8px; }
.step-card p { color: var(--text-light); font-size: 14px; }

.steps-connector {
  display: none;
}

@media (min-width: 768px) {
  .step-card::after {
    content: '';
    position: absolute;
    top: 30px;
    right: -12px;
    width: 24px;
    height: 2px;
    background: var(--border);
  }
  .step-card:last-child::after { display: none; }
}

/* ========== Download Section ========== */
.download-cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.download-card {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  text-align: center;
  box-shadow: var(--shadow);
  border: 2px solid transparent;
  transition: var(--transition);
  position: relative;
}

.download-card.featured {
  border-color: var(--primary);
  transform: scale(1.03);
}

.download-card .badge {
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--primary);
  color: #fff;
  padding: 4px 16px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 600;
}

.download-card .os-icon { font-size: 48px; margin-bottom: 14px; }
.download-card h3 { font-size: 20px; color: var(--secondary); margin-bottom: 6px; }
.download-card .ver { font-size: 13px; color: var(--text-muted); margin-bottom: 16px; }
.download-card .dl-info { font-size: 13px; color: var(--text-light); margin-bottom: 20px; }

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

.faq-item {
  background: var(--bg-white);
  border-radius: var(--radius);
  margin-bottom: 12px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.04);
  overflow: hidden;
}

.faq-q {
  padding: 18px 24px;
  font-weight: 600;
  font-size: 16px;
  color: var(--secondary);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: var(--transition);
}

.faq-q:hover { background: #fafafa; }
.faq-q::after { content: '+'; font-size: 22px; color: var(--primary); }

.faq-a {
  padding: 0 24px 18px;
  color: var(--text-light);
  font-size: 14px;
  line-height: 1.9;
  display: none;
}

.faq-item.open .faq-a { display: block; }
.faq-item.open .faq-q::after { content: '−'; }

/* ========== Version Info ========== */
.version-info {
  background: linear-gradient(135deg, var(--secondary), #3d566e);
  color: #fff;
  padding: 50px 0;
  text-align: center;
}

.version-info h2 { font-size: 28px; margin-bottom: 10px; }
.version-info .ver-num { font-size: 48px; font-weight: 800; margin-bottom: 16px; }
.version-info .ver-date { opacity: 0.8; font-size: 15px; margin-bottom: 24px; }

/* ========== Tech Specs ========== */
.specs-table {
  width: 100%;
  border-collapse: collapse;
  background: var(--bg-white);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
}

.specs-table th,
.specs-table td {
  padding: 14px 20px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

.specs-table th {
  background: var(--secondary);
  color: #fff;
  font-weight: 600;
  font-size: 14px;
}

.specs-table td { font-size: 14px; color: var(--text-light); }
.specs-table tr:last-child td { border-bottom: none; }

/* ========== CTA Section ========== */
.cta-section {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  text-align: center;
  padding: 60px 0;
}

.cta-section h2 { font-size: 30px; margin-bottom: 12px; }
.cta-section p { opacity: 0.9; font-size: 16px; margin-bottom: 24px; }

/* ========== Page Header (sub pages) ========== */
.page-header {
  background: linear-gradient(135deg, var(--secondary), #3d566e);
  color: #fff;
  padding: 50px 0;
  text-align: center;
}

.page-header h1 { font-size: 34px; font-weight: 700; margin-bottom: 8px; }
.page-header p { opacity: 0.85; font-size: 16px; max-width: 600px; margin: 0 auto; }

/* ========== Breadcrumb ========== */
.breadcrumb {
  padding: 14px 20px;
  background: var(--bg-white);
  border-bottom: 1px solid var(--border);
  font-size: 14px;
  color: var(--text-muted);
}

.breadcrumb .container { display: flex; gap: 8px; align-items: center; }
.breadcrumb a { color: var(--primary); }
.breadcrumb span { color: var(--text-muted); }

/* ========== Content Area ========== */
.content-area {
  padding: 50px 0;
}

.content-area h2 {
  font-size: 26px;
  color: var(--secondary);
  margin: 40px 0 16px;
  padding-bottom: 10px;
  border-bottom: 2px solid var(--primary);
  display: inline-block;
}

.content-area h2:first-child { margin-top: 0; }

.content-area h3 {
  font-size: 20px;
  color: var(--secondary);
  margin: 28px 0 12px;
}

.content-area p {
  color: var(--text-light);
  margin-bottom: 16px;
  line-height: 2;
}

.content-area ul,
.content-area ol {
  margin-bottom: 16px;
  padding-left: 20px;
  color: var(--text-light);
  line-height: 2;
}

.content-area ul li,
.content-area ol li { margin-bottom: 6px; }

.content-area ul { list-style: disc; }

/* ========== Tutorial Steps ========== */
.tutorial-step {
  display: flex;
  gap: 24px;
  margin-bottom: 40px;
  padding: 30px;
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
}

.tutorial-step .ts-num {
  flex-shrink: 0;
  width: 50px;
  height: 50px;
  background: var(--primary);
  color: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
  font-weight: 700;
}

.tutorial-step .ts-content h3 {
  font-size: 20px;
  color: var(--secondary);
  margin: 0 0 10px;
}

.tutorial-step .ts-content p {
  color: var(--text-light);
  font-size: 14px;
  line-height: 1.9;
}

.tutorial-step .ts-content img {
  margin-top: 16px;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

/* ========== Footer ========== */
.site-footer {
  background: var(--secondary);
  color: #ccc;
  padding: 50px 0 0;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  padding-bottom: 36px;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}

.footer-col h4 {
  color: #fff;
  font-size: 16px;
  margin-bottom: 16px;
}

.footer-col p { font-size: 13px; line-height: 1.8; }

.footer-col a {
  display: block;
  color: #aaa;
  font-size: 13px;
  padding: 4px 0;
  transition: var(--transition);
}

.footer-col a:hover { color: var(--primary-light); }

.footer-bottom {
  padding: 20px 0;
  text-align: center;
  font-size: 13px;
  color: #888;
}

.footer-bottom a { color: var(--primary-light); }

/* ========== Responsive ========== */
@media (max-width: 992px) {
  .features-grid,
  .platforms-grid,
  .download-cards { grid-template-columns: repeat(2, 1fr); }
  .screenshots-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .feature-list-2col { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .steps { grid-template-columns: 1fr; }
  .step-card::after { display: none; }
  .download-card.featured { transform: none; }
}

@media (max-width: 768px) {
  .hero h1 { font-size: 28px; }
  .hero .subtitle { font-size: 16px; }
  .section-title { font-size: 24px; }
  .features-grid,
  .platforms-grid,
  .download-cards,
  .screenshots-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .hero-buttons { flex-direction: column; align-items: center; }
  .hero-buttons .btn { width: 80%; }
  .tutorial-step { flex-direction: column; }
  .main-nav { display: none; }
  .mobile-menu-btn { display: block; }
  .main-nav.mobile-open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--bg-white);
    box-shadow: var(--shadow-lg);
    padding: 10px 20px;
  }
}

@media (max-width: 480px) {
  .container { padding: 0 14px; }
  .hero { padding: 50px 0 40px; }
  .section { padding: 40px 0; }
}

/* ========== Download Page Buttons ========== */
.btn-dl-primary {
  display: inline-block;
  width: 100%;
  padding: 12px 30px;
  border-radius: 30px;
  font-weight: 600;
  font-size: 16px;
  cursor: pointer;
  transition: var(--transition);
  border: none;
  text-decoration: none;
  background: var(--primary);
  color: #fff;
}
.btn-dl-primary:hover { background: var(--primary-dark); transform: translateY(-2px); box-shadow: 0 4px 14px rgba(224,90,51,0.3); }

.btn-dl-secondary {
  display: inline-block;
  width: 100%;
  padding: 12px 30px;
  border-radius: 30px;
  font-weight: 600;
  font-size: 15px;
  cursor: pointer;
  transition: var(--transition);
  border: 2px solid var(--border);
  text-decoration: none;
  background: #f5f5f5;
  color: var(--text);
  margin-top: 10px;
}
.btn-dl-secondary:hover { background: #e8e8e8; border-color: #ccc; transform: translateY(-2px); }

/* ========== Modal Overlay ========== */
.modal-overlay {
  display: none;
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(0,0,0,0.55);
  z-index: 9999;
  align-items: center;
  justify-content: center;
  padding: 20px;
}
.modal-overlay.active {
  display: flex;
}

.modal-box {
  background: #fff;
  border-radius: var(--radius-lg);
  padding: 36px 32px 28px;
  max-width: 520px;
  width: 100%;
  position: relative;
  text-align: center;
  box-shadow: 0 20px 60px rgba(0,0,0,0.3);
  max-height: 90vh;
  overflow-y: auto;
}

.modal-close {
  position: absolute;
  top: 12px;
  right: 16px;
  background: none;
  border: none;
  font-size: 28px;
  color: #999;
  cursor: pointer;
  line-height: 1;
  padding: 4px 8px;
  border-radius: 4px;
  transition: var(--transition);
}
.modal-close:hover { color: #333; background: #f0f0f0; }

.modal-title {
  font-size: 20px;
  font-weight: 700;
  color: var(--secondary);
  margin-bottom: 20px;
}

/* ========== QR Code Breathing Border ========== */
@keyframes breathe {
  0%, 100% {
    box-shadow: 0 0 0 0 rgba(224, 90, 51, 0.25);
    border-color: rgba(224, 90, 51, 0.25);
  }
  50% {
    box-shadow: 0 0 0 7px rgba(224, 90, 51, 0.05);
    border-color: rgba(224, 90, 51, 0.75);
  }
}

.qrcode-wrap {
  display: inline-block;
  border: 3px solid rgba(224, 90, 51, 0.25);
  border-radius: 14px;
  padding: 10px;
  background: #fff;
  margin-bottom: 12px;
  animation: breathe 2.6s ease-in-out infinite;
}

.qrcode-img {
  display: block;
  width: 150px;
  height: 150px;
  border-radius: 6px;
}

.modal-scan-text {
  font-size: 15px;
  color: var(--text);
  font-weight: 600;
  margin-bottom: 4px;
}

.modal-extract-hint {
  font-size: 14px;
  color: var(--primary);
  font-weight: 600;
  margin-bottom: 20px;
  background: rgba(224,90,51,0.08);
  display: inline-block;
  padding: 4px 16px;
  border-radius: 20px;
}

.modal-features {
  text-align: left;
  margin-bottom: 12px;
}

.modal-features h4 {
  font-size: 15px;
  color: var(--secondary);
  margin-bottom: 10px;
}

.modal-features ul {
  list-style: none;
  padding: 0;
}

.modal-features ul li {
  padding: 4px 0;
  font-size: 13px;
  color: var(--text-light);
  line-height: 1.8;
}

.modal-features ul li::before {
  content: '✓ ';
  color: #27ae60;
  font-weight: 700;
  margin-right: 6px;
}

.modal-warning {
  background: #fff8e1;
  border: 1px solid #ffe082;
  border-radius: var(--radius);
  padding: 12px 16px;
  font-size: 13px;
  color: #e65100;
  line-height: 1.7;
}

.modal-warning strong { color: #d84315; }