/* ==========================================================================
   ShopCrew (Project Zenith) Official Website Stylesheet
   Modern, Clean, Responsive Design System (Pure Vanilla CSS)
   ========================================================================== */

/* --- 1. CSS Custom Properties & Design Tokens --- */
:root {
  /* Brand Palette */
  --primary: #2563EB;
  --primary-hover: #1D4ED8;
  --primary-light: #EFF6FF;
  --primary-glow: rgba(37, 99, 235, 0.12);
  
  --accent: #0284C7;
  --accent-light: #F0F9FF;
  
  --success: #10B981;
  --success-bg: #ECFDF5;
  --warning: #F59E0B;
  --warning-bg: #FFFBEB;
  --danger: #EF4444;
  --danger-bg: #FEF2F2;
  
  /* Neutral Palette */
  --bg-main: #FAFAFC;
  --bg-card: #FFFFFF;
  --bg-card-hover: #FFFFFF;
  --bg-subtle: #F1F5F9;
  --bg-dark: #0F172A;
  --bg-dark-card: #1E293B;
  
  --text-primary: #0F172A;
  --text-secondary: #475569;
  --text-muted: #94A3B8;
  --text-white: #FFFFFF;
  
  /* Borders & Dividers */
  --border-subtle: #E2E8F0;
  --border-card: #E2E8F0;
  --border-focus: #3B82F6;
  
  /* Shadows & Elevation */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.06), 0 2px 4px -2px rgba(0, 0, 0, 0.04);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.07), 0 4px 6px -4px rgba(0, 0, 0, 0.04);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.08), 0 8px 10px -6px rgba(0, 0, 0, 0.04);
  --shadow-card: 0 2px 8px rgba(15, 23, 42, 0.04), 0 1px 2px rgba(15, 23, 42, 0.02);
  --shadow-card-hover: 0 12px 24px -4px rgba(15, 23, 42, 0.08), 0 4px 6px -2px rgba(15, 23, 42, 0.04);

  /* Typography */
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  
  /* Layout & Spacing */
  --max-width: 1200px;
  --header-height: 72px;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 9999px;
  
  /* Transitions */
  --transition-fast: 0.15s ease;
  --transition-normal: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

/* --- 2. CSS Reset & Base Styles --- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-family);
  background-color: var(--bg-main);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
}

a {
  color: inherit;
  text-decoration: none;
  transition: color var(--transition-fast);
}

ul, ol {
  list-style: none;
}

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

button, input, select {
  font-family: inherit;
  font-size: inherit;
}

.container {
  width: 100%;
  max-width: var(--max-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: 24px;
  padding-right: 24px;
}

/* --- 3. Navbar & Header --- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  height: var(--header-height);
  background: rgba(255, 255, 255, 0.88);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-subtle);
  transition: all var(--transition-normal);
}

.site-header.scrolled {
  background: rgba(255, 255, 255, 0.96);
  box-shadow: var(--shadow-sm);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--text-primary);
}

.brand-logo img {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.08);
}

.brand-badge {
  font-size: 0.72rem;
  font-weight: 600;
  background: var(--primary-light);
  color: var(--primary);
  padding: 2px 8px;
  border-radius: var(--radius-full);
  border: 1px solid rgba(37, 99, 235, 0.2);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav-link {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color var(--transition-fast);
}

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

.nav-actions {
  display: flex;
  align-items: center;
  gap: 16px;
}

.mobile-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  color: var(--text-primary);
}

/* --- 4. Buttons & UI Components --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-weight: 600;
  font-size: 0.95rem;
  padding: 10px 20px;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.btn-primary {
  background-color: var(--primary);
  color: var(--text-white);
  box-shadow: 0 2px 4px rgba(37, 99, 235, 0.2);
}

.btn-primary:hover {
  background-color: var(--primary-hover);
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
  transform: translateY(-1px);
}

.btn-secondary {
  background-color: var(--bg-card);
  color: var(--text-primary);
  border-color: var(--border-card);
  box-shadow: var(--shadow-sm);
}

.btn-secondary:hover {
  background-color: var(--bg-subtle);
  border-color: #CBD5E1;
}

.btn-lg {
  padding: 14px 28px;
  font-size: 1.05rem;
  border-radius: var(--radius-lg);
}

.btn-sm {
  padding: 6px 14px;
  font-size: 0.85rem;
  border-radius: var(--radius-sm);
}

/* --- 5. Hero Section --- */
.hero-section {
  padding: 64px 0 80px;
  text-align: center;
  position: relative;
  background: radial-gradient(circle at 50% -20%, rgba(37, 99, 235, 0.06) 0%, transparent 70%);
}

.hero-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-secondary);
  box-shadow: var(--shadow-sm);
  margin-bottom: 24px;
}

.hero-pill-dot {
  width: 8px;
  height: 8px;
  background: var(--success);
  border-radius: 50%;
}

.hero-title {
  font-size: 3.25rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.15;
  color: var(--text-primary);
  margin-bottom: 20px;
  max-width: 900px;
  margin-left: auto;
  margin-right: auto;
}

.hero-title .highlight {
  color: var(--primary);
  position: relative;
}

.hero-subtitle {
  font-size: 1.2rem;
  color: var(--text-secondary);
  max-width: 720px;
  margin: 0 auto 36px;
  line-height: 1.6;
}

.hero-cta {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  margin-bottom: 48px;
  flex-wrap: wrap;
}

.hero-platforms {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 24px;
  color: var(--text-muted);
  font-size: 0.9rem;
  font-weight: 500;
  flex-wrap: wrap;
}

.platform-tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--text-secondary);
  background: rgba(255, 255, 255, 0.7);
  padding: 4px 12px;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-subtle);
}

/* --- 6. App Window Mockup (Hero Preview) --- */
.hero-mockup-wrapper {
  margin-top: 56px;
  position: relative;
}

.app-window {
  background: var(--bg-card);
  border-radius: var(--radius-xl);
  border: 1px solid var(--border-card);
  box-shadow: 0 25px 50px -12px rgba(15, 23, 42, 0.12), 0 0 0 1px rgba(0, 0, 0, 0.03);
  overflow: hidden;
  text-align: left;
}

.window-header {
  background: #F8FAFC;
  padding: 12px 20px;
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.window-dots {
  display: flex;
  gap: 8px;
}

.window-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
}

.dot-red { background: #FF5F56; }
.dot-yellow { background: #FFBD2E; }
.dot-green { background: #27C93F; }

.window-title {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 8px;
}

.window-nav-tabs {
  display: flex;
  gap: 8px;
}

.window-tab-btn {
  padding: 4px 12px;
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--text-secondary);
  background: transparent;
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.window-tab-btn:hover {
  background: #E2E8F0;
}

.window-tab-btn.active {
  background: #FFFFFF;
  color: var(--primary);
  border-color: var(--border-subtle);
  box-shadow: var(--shadow-sm);
}

.window-content {
  padding: 28px;
  background: #FAFBFD;
  min-height: 380px;
}

.tab-pane {
  display: none;
}

.tab-pane.active {
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: 24px;
  animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Mockup Internal Layout */
.mock-sidebar {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.mock-sidebar-item {
  padding: 10px 12px;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-secondary);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  gap: 8px;
  background: transparent;
}

.mock-sidebar-item.selected {
  background: var(--primary-light);
  color: var(--primary);
  font-weight: 600;
}

.mock-main {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.mock-header-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border-subtle);
}

.mock-badge-status {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.75rem;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: var(--radius-full);
}

.status-green { background: var(--success-bg); color: var(--success); }
.status-blue { background: var(--primary-light); color: var(--primary); }

.mock-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.85rem;
}

.mock-table th {
  text-align: left;
  padding: 8px 12px;
  background: #F8FAFC;
  color: var(--text-secondary);
  font-weight: 600;
  border-bottom: 1px solid var(--border-subtle);
}

.mock-table td {
  padding: 10px 12px;
  border-bottom: 1px solid #F1F5F9;
  color: var(--text-primary);
}

/* --- 7. Section Shared Header --- */
.section {
  padding: 96px 0;
}

.section-alt {
  background-color: #FFFFFF;
  border-top: 1px solid var(--border-subtle);
  border-bottom: 1px solid var(--border-subtle);
}

.section-header {
  text-align: center;
  max-width: 760px;
  margin: 0 auto 64px;
}

.section-pill {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--primary);
  background: var(--primary-light);
  padding: 4px 12px;
  border-radius: var(--radius-full);
  margin-bottom: 16px;
}

.section-title {
  font-size: 2.25rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--text-primary);
  margin-bottom: 16px;
}

.section-desc {
  font-size: 1.1rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* --- 8. Core Features Grid (8 Modules) --- */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(270px, 1fr));
  gap: 24px;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-lg);
  padding: 28px 24px;
  transition: all var(--transition-normal);
  box-shadow: var(--shadow-card);
  display: flex;
  flex-direction: column;
  position: relative;
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-card-hover);
  border-color: #CBD5E1;
}

.feature-icon-box {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  background: var(--primary-light);
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  margin-bottom: 20px;
}

.feature-tag {
  position: absolute;
  top: 24px;
  right: 24px;
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--accent);
  background: var(--accent-light);
  padding: 2px 8px;
  border-radius: var(--radius-full);
}

.feature-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.feature-desc {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 16px;
  flex-grow: 1;
}

.feature-bullets {
  border-top: 1px solid #F1F5F9;
  padding-top: 14px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.feature-bullet {
  font-size: 0.8rem;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 6px;
}

.feature-bullet::before {
  content: "•";
  color: var(--primary);
  font-weight: bold;
}

/* --- 9. Interactive Profit & ROI Calculator Playground --- */
.calc-card {
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
  padding: 40px;
  max-width: 980px;
  margin: 0 auto;
}

.calc-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: center;
}

.calc-inputs {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.form-label {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-secondary);
  display: flex;
  justify-content: space-between;
}

.form-input-wrapper {
  position: relative;
  display: flex;
  align-items: center;
}

.form-input-prefix, .form-input-suffix {
  position: absolute;
  font-size: 0.9rem;
  color: var(--text-muted);
  pointer-events: none;
}

.form-input-prefix { left: 14px; }
.form-input-suffix { right: 14px; }

.form-control {
  width: 100%;
  padding: 10px 14px;
  padding-left: 32px;
  padding-right: 32px;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  font-size: 0.95rem;
  color: var(--text-primary);
  background: #FFFFFF;
  transition: border-color var(--transition-fast);
}

.form-control:focus {
  outline: none;
  border-color: var(--border-focus);
  box-shadow: 0 0 0 3px var(--primary-glow);
}

.calc-results {
  background: #F8FAFC;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 28px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.result-main {
  text-align: center;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--border-subtle);
}

.result-label {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 6px;
}

.result-value-big {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--primary);
  letter-spacing: -0.02em;
}

.result-stats-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.result-stat-card {
  background: #FFFFFF;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 14px;
  text-align: center;
}

.stat-title {
  font-size: 0.75rem;
  color: var(--text-muted);
  font-weight: 500;
  margin-bottom: 4px;
}

.stat-number {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
}

/* --- 10. Technology & Security Highlights --- */
.tech-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 32px;
}

.tech-card {
  background: #FFFFFF;
  border: 1px solid var(--border-card);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow-sm);
  display: flex;
  gap: 20px;
}

.tech-icon {
  font-size: 2rem;
  color: var(--primary);
  flex-shrink: 0;
}

.tech-info h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--text-primary);
}

.tech-info p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* --- 11. Download Section --- */
.download-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
  max-width: 900px;
  margin: 0 auto;
}

.download-card {
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-xl);
  padding: 36px 32px;
  text-align: center;
  box-shadow: var(--shadow-md);
  transition: all var(--transition-normal);
  display: flex;
  flex-direction: column;
  align-items: center;
}

.download-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
  border-color: #CBD5E1;
}

.os-icon {
  width: 64px;
  height: 64px;
  background: var(--primary-light);
  color: var(--primary);
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2rem;
  margin-bottom: 20px;
}

.os-title {
  font-size: 1.4rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.os-version {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 24px;
}

.download-meta {
  margin-top: 20px;
  font-size: 0.8rem;
  color: var(--text-muted);
  display: flex;
  flex-direction: column;
  gap: 4px;
}

/* --- 12. FAQ Section --- */
.faq-list {
  max-width: 800px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: all var(--transition-fast);
}

.faq-item:hover {
  border-color: #CBD5E1;
}

.faq-question {
  padding: 20px 24px;
  font-weight: 600;
  font-size: 1.05rem;
  color: var(--text-primary);
  display: flex;
  justify-content: space-between;
  align-items: center;
  cursor: pointer;
  user-select: none;
}

.faq-arrow {
  font-size: 1.2rem;
  color: var(--text-muted);
  transition: transform var(--transition-normal);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  padding: 0 24px;
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.7;
}

.faq-item.open .faq-arrow {
  transform: rotate(180deg);
  color: var(--primary);
}

.faq-item.open .faq-answer {
  padding-bottom: 20px;
}

/* --- 13. Footer --- */
.site-footer {
  background: var(--bg-dark);
  color: #94A3B8;
  padding: 64px 0 32px;
  margin-top: auto;
  border-top: 1px solid #1E293B;
}

.footer-top {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
  padding-bottom: 48px;
  border-bottom: 1px solid #1E293B;
}

.footer-brand h4 {
  font-size: 1.25rem;
  color: var(--text-white);
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.footer-brand p {
  font-size: 0.9rem;
  line-height: 1.6;
  max-width: 320px;
}

.footer-col h5 {
  font-size: 0.95rem;
  color: var(--text-white);
  margin-bottom: 16px;
  font-weight: 600;
}

.footer-col ul {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-col a {
  font-size: 0.85rem;
  color: #94A3B8;
  transition: color var(--transition-fast);
}

.footer-col a:hover {
  color: var(--text-white);
}

.footer-bottom {
  padding-top: 32px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.85rem;
  flex-wrap: wrap;
  gap: 16px;
}

/* --- 14. Responsive Breakpoints --- */
@media (max-width: 992px) {
  .hero-title {
    font-size: 2.5rem;
  }
  .calc-grid {
    grid-template-columns: 1fr;
    gap: 28px;
  }
  .footer-top {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
  }
  .tab-pane.active {
    grid-template-columns: 1fr;
  }
  .mock-sidebar {
    display: none;
  }
}

@media (max-width: 768px) {
  .nav-links, .nav-actions {
    display: none;
  }
  .mobile-toggle {
    display: block;
  }
  .nav-container.mobile-open .nav-links {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: var(--header-height);
    left: 0;
    width: 100%;
    background: #FFFFFF;
    padding: 24px;
    box-shadow: var(--shadow-lg);
    border-bottom: 1px solid var(--border-subtle);
    gap: 16px;
  }
  .nav-container.mobile-open .nav-actions {
    display: flex;
    position: absolute;
    top: calc(var(--header-height) + 220px);
    left: 0;
    width: 100%;
    background: #FFFFFF;
    padding: 0 24px 24px;
  }
  .hero-title {
    font-size: 2rem;
  }
  .hero-subtitle {
    font-size: 1rem;
  }
  .download-grid {
    grid-template-columns: 1fr;
  }
  .calc-card {
    padding: 24px;
  }
  .footer-top {
    grid-template-columns: 1fr;
  }
  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }
}

/* ==========================================================================
   --- 10. Download Portal & Dynamic Download Component Styles ---
   ========================================================================== */

.download-portal-header {
  text-align: center;
  margin-bottom: 36px;
}

.portal-main-title {
  font-size: 2.25rem;
  font-weight: 800;
  color: var(--text-primary);
  letter-spacing: -0.02em;
  margin-bottom: 12px;
}

.portal-main-lead {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 680px;
  margin: 0 auto;
}

.download-portal-platforms {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 20px;
}

.portal-platform-btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 12px 24px;
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-full);
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-secondary);
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-normal);
}

.portal-platform-btn:hover {
  border-color: var(--primary);
  color: var(--primary);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.portal-platform-btn.active {
  background: var(--primary);
  border-color: var(--primary);
  color: #FFFFFF;
  box-shadow: 0 4px 14px var(--primary-glow);
}

.platform-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  flex-shrink: 0;
}

.portal-platform-btn.active .platform-dot {
  background-color: #FFFFFF !important;
}

.download-portal-os {
  display: flex;
  gap: 10px;
  justify-content: center;
  margin-bottom: 32px;
}

.portal-os-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 20px;
  background: var(--bg-subtle);
  border: 1px solid transparent;
  border-radius: var(--radius-full);
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition-normal);
}

.portal-os-btn:hover {
  background: #E2E8F0;
  color: var(--text-primary);
}

.portal-os-btn.active {
  background: var(--bg-dark);
  color: #FFFFFF;
  box-shadow: var(--shadow-md);
}

/* Main Hero Download Card */
.download-hero-card {
  background: linear-gradient(135deg, #FFFFFF 0%, #F8FAFC 100%);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-xl);
  padding: 48px 36px;
  text-align: center;
  box-shadow: var(--shadow-lg);
  margin-bottom: 48px;
  position: relative;
  overflow: hidden;
}

.download-hero-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
}

.download-hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  background: var(--primary-light);
  color: var(--primary);
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 20px;
}

.pulse-dot {
  width: 8px;
  height: 8px;
  background-color: var(--success);
  border-radius: 50%;
  box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.4);
  animation: pulseGreen 2s infinite;
}

@keyframes pulseGreen {
  0% {
    box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.5);
  }
  70% {
    box-shadow: 0 0 0 8px rgba(16, 185, 129, 0);
  }
  100% {
    box-shadow: 0 0 0 0 rgba(16, 185, 129, 0);
  }
}

.download-hero-title {
  font-size: 2rem;
  font-weight: 800;
  color: var(--text-primary);
  margin-bottom: 10px;
}

.download-hero-subtitle {
  font-size: 1rem;
  color: var(--text-secondary);
  margin-bottom: 32px;
}

.download-hero-cta {
  margin-bottom: 24px;
}

.download-action-btn {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  padding: 16px 40px;
  font-size: 1.15rem;
  box-shadow: 0 8px 20px -4px rgba(37, 99, 235, 0.4);
}

.download-hero-meta {
  display: flex;
  justify-content: center;
  gap: 20px;
  flex-wrap: wrap;
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* History Section */
.download-history-section {
  margin-bottom: 48px;
}

.download-history-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 20px;
}

.download-history-title {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
}

.download-history-count {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.download-history-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.download-history-item {
  padding: 20px 24px;
}

.history-item-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
}

.history-version-info {
  display: flex;
  align-items: center;
  gap: 10px;
}

.history-ver-tag {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-primary);
}

.history-type-badge {
  font-size: 0.75rem;
  font-weight: 600;
  padding: 2px 10px;
  border-radius: var(--radius-full);
}

.badge-release {
  background: #ECFDF5;
  color: #059669;
}

.badge-hotfix {
  background: #EFF6FF;
  color: #2563EB;
}

.history-time {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.history-log-body {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.6;
  white-space: pre-wrap;
  word-break: break-word;
}

.history-item-bottom {
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px dashed var(--border-subtle);
}

.history-download-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--primary);
}

.history-download-link:hover {
  text-decoration: underline;
}

.download-history-empty {
  padding: 32px;
  text-align: center;
  color: var(--text-muted);
}

/* Trust Section */
.portal-trust-section {
  margin-bottom: 40px;
}

.portal-trust-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 20px;
  text-align: center;
}

.portal-trust-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.trust-item {
  display: flex;
  gap: 16px;
  padding: 20px;
}

.trust-icon {
  font-size: 1.8rem;
  flex-shrink: 0;
}

.trust-text h4 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 6px;
  color: var(--text-primary);
}

.trust-text p {
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

/* Help Box */
.portal-help-box {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 24px 32px;
  background: var(--primary-light);
  border-color: #BFDBFE;
  flex-wrap: wrap;
  gap: 16px;
}

.portal-help-content h4 {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 4px;
}

.portal-help-content p {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.portal-help-actions {
  display: flex;
  gap: 10px;
}

/* Inline Widget in index.html */
.inline-download-switchers {
  display: flex;
  justify-content: center;
  margin-bottom: 24px;
}

.inline-platform-tabs {
  display: inline-flex;
  background: var(--bg-card);
  padding: 4px;
  border-radius: var(--radius-full);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border-card);
  gap: 4px;
}

.inline-tab-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 18px;
  border-radius: var(--radius-full);
  border: none;
  background: transparent;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.inline-tab-btn.active {
  background: var(--primary);
  color: #FFFFFF;
}

.download-card.recommended {
  border-color: var(--primary);
  box-shadow: 0 8px 24px var(--primary-glow);
  position: relative;
}

.download-rec-badge {
  position: absolute;
  top: -12px;
  right: 20px;
  background: var(--primary);
  color: #FFFFFF;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 4px 12px;
  border-radius: var(--radius-full);
  box-shadow: var(--shadow-sm);
}

.inline-download-footer {
  text-align: center;
  margin-top: 24px;
}

.inline-more-link {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--primary);
  transition: all var(--transition-fast);
}

.inline-more-link:hover {
  text-decoration: underline;
}

.download-loading-skeleton {
  text-align: center;
  padding: 40px;
  color: var(--text-muted);
  font-size: 0.95rem;
}

@media (max-width: 768px) {
  .portal-trust-grid {
    grid-template-columns: 1fr;
  }
  .portal-help-box {
    flex-direction: column;
    align-items: flex-start;
  }
  .download-hero-card {
    padding: 32px 20px;
  }
  .download-hero-title {
    font-size: 1.5rem;
  }
  .download-action-btn {
    width: 100%;
    padding: 14px 20px;
    font-size: 1rem;
  }
}

/* ==========================================================================
   --- 11. Contact Us Page Styles ---
   ========================================================================== */

.contact-header {
  text-align: center;
  margin-bottom: 40px;
}

.contact-title {
  font-size: 2.25rem;
  font-weight: 800;
  color: var(--text-primary);
  letter-spacing: -0.02em;
  margin-top: 12px;
  margin-bottom: 12px;
}

.contact-lead {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 680px;
  margin: 0 auto;
}

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

.contact-card {
  padding: 32px 28px;
  display: flex;
  flex-direction: column;
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-md);
  transition: all var(--transition-normal);
}

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

.contact-card-top {
  margin-bottom: 20px;
}

.manager-avatar-wrapper {
  display: flex;
  align-items: center;
  gap: 16px;
}

.manager-avatar-circle {
  width: 52px;
  height: 52px;
  border-radius: 50%;
  color: #FFFFFF;
  font-size: 1.35rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-sm);
  flex-shrink: 0;
}

.manager-name {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 4px;
}

.manager-role-tag {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 600;
  padding: 2px 10px;
  background: var(--primary-light);
  color: var(--primary);
  border-radius: var(--radius-full);
}

.contact-info-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-bottom: 24px;
}

.contact-info-item {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.95rem;
}

.info-label {
  font-weight: 600;
  color: var(--text-secondary);
  flex-shrink: 0;
}

.info-val {
  font-weight: 700;
  color: var(--text-primary);
  font-family: var(--font-mono);
}

.phone-link {
  color: var(--primary);
  transition: color var(--transition-fast);
}

.phone-link:hover {
  text-decoration: underline;
}

.copy-btn {
  padding: 2px 8px;
  background: var(--bg-subtle);
  border: 1px solid var(--border-subtle);
  border-radius: 4px;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.copy-btn:hover {
  background: var(--primary);
  border-color: var(--primary);
  color: #FFFFFF;
}

.scope-item {
  align-items: flex-start;
  margin-top: 4px;
}

.info-desc {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.5;
}

/* QR Code Display */
.qrcode-box {
  margin-top: auto;
  padding-top: 20px;
  border-top: 1px dashed var(--border-subtle);
  text-align: center;
}

.qrcode-img-wrap {
  width: 160px;
  height: 160px;
  margin: 0 auto 12px;
  padding: 8px;
  background: #FFFFFF;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform var(--transition-normal);
}

.qrcode-img-wrap:hover {
  transform: scale(1.05);
}

.contact-qrcode-img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  border-radius: 4px;
}

.qrcode-hint {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-secondary);
}

/* Service Commitments */
.contact-commit-section {
  margin-top: 20px;
}

.commit-section-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 20px;
  text-align: center;
}

.commit-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.commit-card {
  padding: 20px;
  display: flex;
  gap: 16px;
}

.commit-icon {
  font-size: 1.8rem;
  flex-shrink: 0;
}

.commit-card h4 {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 4px;
}

.commit-card p {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.5;
}

/* Toast Message */
.contact-toast {
  position: fixed;
  bottom: 30px;
  left: 50%;
  transform: translateX(-50%) translateY(100px);
  background: rgba(15, 23, 42, 0.92);
  color: #FFFFFF;
  padding: 10px 24px;
  border-radius: var(--radius-full);
  font-size: 0.9rem;
  font-weight: 600;
  box-shadow: var(--shadow-lg);
  opacity: 0;
  pointer-events: none;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  z-index: 9999;
}

.contact-toast.show {
  transform: translateX(-50%) translateY(0);
  opacity: 1;
}

@media (max-width: 768px) {
  .contact-grid {
    grid-template-columns: 1fr;
  }
  .commit-grid {
    grid-template-columns: 1fr;
  }
  .contact-title {
    font-size: 1.6rem;
  }
}