/* ===== CSS Variables ===== */
:root {
  --primary: #ff6b35;
  --primary-dark: #e55a2b;
  --primary-light: #fff3ef;
  --secondary: #7c3aed;
  --secondary-light: #f3effe;
  --accent: #fbbf24;
  --text-primary: #1a1a2e;
  --text-secondary: #555770;
  --text-light: #9ca3af;
  --bg-white: #ffffff;
  --bg-light: #fafafa;
  --bg-dark: #1a1a2e;
  --bg-gradient: linear-gradient(135deg, #ff6b35, #ff8f5e, #fbbf24);
  --border: #eee;
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.12);
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --transition: all 0.3s ease;
  --max-width: 1100px;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial,
    sans-serif;
  color: var(--text-primary);
  line-height: 1.6;
  background: var(--bg-white);
  -webkit-font-smoothing: antialiased;
}

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

ul {
  list-style: none;
}

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

/* ===== Utility ===== */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 80px 0;
}

.section-title {
  font-size: 2rem;
  font-weight: 700;
  text-align: center;
  margin-bottom: 16px;
}

.section-subtitle {
  text-align: center;
  color: var(--text-secondary);
  font-size: 1.05rem;
  margin-bottom: 48px;
  max-width: 520px;
  margin-left: auto;
  margin-right: auto;
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 32px;
  border-radius: 100px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  border: none;
  transition: var(--transition);
}

.btn-primary {
  background: var(--bg-gradient);
  color: #fff;
  box-shadow: 0 4px 16px rgba(255, 107, 53, 0.3);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 24px rgba(255, 107, 53, 0.4);
}

.btn-secondary {
  background: var(--bg-white);
  color: var(--primary);
  border: 2px solid var(--primary);
}

.btn-secondary:hover {
  background: var(--primary-light);
}

/* ===== Navbar ===== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: var(--transition);
}

.navbar.scrolled {
  border-bottom-color: var(--border);
  box-shadow: var(--shadow-sm);
}

.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}

.navbar-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--primary);
}

.navbar-brand .logo-icon {
  width: 36px;
  height: 36px;
  background: var(--bg-gradient);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 1.2rem;
}

.navbar-links {
  display: flex;
  align-items: center;
  gap: 28px;
}

.navbar-links a {
  font-size: 0.92rem;
  font-weight: 500;
  color: var(--text-secondary);
}

.navbar-links a:hover {
  color: var(--primary);
}

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

.navbar-toggle span {
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: var(--transition);
}

/* ===== Hero ===== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  background: linear-gradient(160deg, #fff5f0 0%, #fef3e2 40%, #f0e6ff 100%);
  padding-top: 68px;
}

.hero::before {
  content: "";
  position: absolute;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(255, 107, 53, 0.15) 0%, transparent 70%);
  top: -50px;
  right: -50px;
  border-radius: 50%;
}

.hero .container {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}

.hero-content {
  max-width: 500px;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  background: rgba(255, 107, 53, 0.1);
  border-radius: 100px;
  font-size: 0.85rem;
  color: var(--primary);
  font-weight: 500;
  margin-bottom: 24px;
}

.hero-title {
  font-size: 2.8rem;
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 20px;
}

.hero-title span {
  background: var(--bg-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-desc {
  font-size: 1.1rem;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 32px;
}

.hero-actions {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}

.hero-phone-mockup {
  display: flex;
  align-items: center;
  justify-content: center;
}

.phone-frame {
  width: 280px;
  height: 560px;
  background: var(--bg-white);
  border-radius: 36px;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.15);
  border: 8px solid #222;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 16px;
  padding: 24px;
}

.phone-frame .app-icon {
  width: 72px;
  height: 72px;
  background: var(--bg-gradient);
  border-radius: 18px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2rem;
  box-shadow: 0 4px 16px rgba(255, 107, 53, 0.3);
}

.phone-frame .app-name {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--text-primary);
}

.phone-frame .app-tagline {
  font-size: 0.85rem;
  color: var(--text-secondary);
  text-align: center;
}

.phone-frame .qr-placeholder {
  width: 120px;
  height: 120px;
  background: var(--bg-light);
  border: 2px dashed var(--border);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-light);
  font-size: 0.75rem;
}

.phone-frame .scan-tip {
  font-size: 0.8rem;
  color: var(--text-light);
}

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

.feature-card {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  border: 1px solid var(--border);
  transition: var(--transition);
  text-align: center;
}

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

.feature-card .feature-icon {
  width: 64px;
  height: 64px;
  margin: 0 auto 20px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.8rem;
}

.feature-card .feature-icon.orange {
  background: var(--primary-light);
}

.feature-card .feature-icon.purple {
  background: var(--secondary-light);
}

.feature-card .feature-icon.yellow {
  background: #fef7e0;
}

.feature-card h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 10px;
}

.feature-card p {
  color: var(--text-secondary);
  font-size: 0.9rem;
  line-height: 1.7;
}

/* ===== How it Works ===== */
.steps-container {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  position: relative;
}

.steps-container::before {
  content: "";
  position: absolute;
  top: 36px;
  left: 12%;
  right: 12%;
  height: 2px;
  background: linear-gradient(90deg, var(--primary), var(--secondary));
  opacity: 0.3;
}

.step-item {
  text-align: center;
  position: relative;
  z-index: 1;
}

.step-item .step-circle {
  width: 72px;
  height: 72px;
  margin: 0 auto 20px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.8rem;
  background: var(--bg-white);
  box-shadow: var(--shadow-md);
  border: 3px solid var(--bg-white);
}

.step-item h4 {
  font-size: 1rem;
  margin-bottom: 6px;
}

.step-item p {
  color: var(--text-secondary);
  font-size: 0.85rem;
}

/* ===== Data Stats ===== */
.data-section {
  background: var(--bg-dark);
  color: #fff;
  padding: 80px 0;
}

.data-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
  text-align: center;
}

.data-item .data-value {
  font-size: 2.5rem;
  font-weight: 800;
  background: var(--bg-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1.2;
  margin-bottom: 8px;
}

.data-item .data-label {
  font-size: 0.95rem;
  color: rgba(255, 255, 255, 0.6);
}

/* ===== FAQ ===== */
.faq-list {
  max-width: 720px;
  margin: 0 auto;
}

.faq-item {
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  margin-bottom: 12px;
  overflow: hidden;
  transition: var(--transition);
}

.faq-item:hover {
  border-color: var(--primary);
}

.faq-question {
  width: 100%;
  padding: 20px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--bg-white);
  border: none;
  cursor: pointer;
  font-size: 1rem;
  font-weight: 500;
  color: var(--text-primary);
  font-family: inherit;
  text-align: left;
  transition: var(--transition);
}

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

.faq-question .faq-icon {
  font-size: 1.2rem;
  transition: var(--transition);
  color: var(--text-light);
  flex-shrink: 0;
}

.faq-item.open .faq-question .faq-icon {
  transform: rotate(45deg);
  color: var(--primary);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease;
}

.faq-answer-inner {
  padding: 0 24px 20px;
  color: var(--text-secondary);
  font-size: 0.92rem;
  line-height: 1.8;
}

.faq-item.open .faq-answer {
  max-height: 300px;
}

/* ===== CTA Section ===== */
.cta-section {
  background: var(--bg-gradient);
  color: #fff;
  padding: 80px 0;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.cta-section::before {
  content: "";
  position: absolute;
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, rgba(255, 255, 255, 0.15) 0%, transparent 70%);
  top: -100px;
  left: -100px;
  border-radius: 50%;
}

.cta-section h2 {
  font-size: 2rem;
  margin-bottom: 16px;
  position: relative;
}

.cta-section p {
  font-size: 1.1rem;
  opacity: 0.9;
  margin-bottom: 32px;
  max-width: 480px;
  margin-left: auto;
  margin-right: auto;
  position: relative;
}

.cta-section .btn {
  background: #fff;
  color: var(--primary);
  font-weight: 700;
  position: relative;
}

.cta-section .btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.2);
}

/* ===== Footer ===== */
.footer {
  background: var(--bg-dark);
  color: rgba(255, 255, 255, 0.6);
  padding: 40px 0;
  text-align: center;
}

.footer .container {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 1rem;
  font-weight: 600;
  color: #fff;
}

.footer-brand .logo-icon {
  width: 28px;
  height: 28px;
  background: var(--bg-gradient);
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 0.9rem;
}

.footer-links {
  display: flex;
  gap: 24px;
  font-size: 0.85rem;
}

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

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

.footer-copyright a {
  color: rgba(255, 255, 255, 0.4);
}

.footer-copyright a:hover {
  color: rgba(255, 255, 255, 0.7);
}

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

  .hero-content {
    max-width: 100%;
  }

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

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

  .hero-phone-mockup {
    display: none;
  }

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

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

  .steps-container::before {
    display: none;
  }

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

@media (max-width: 768px) {
  .section {
    padding: 60px 0;
  }

  .section-title {
    font-size: 1.6rem;
  }

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

  .navbar-links {
    position: fixed;
    top: 68px;
    left: 0;
    right: 0;
    background: var(--bg-white);
    flex-direction: column;
    padding: 20px;
    gap: 14px;
    border-bottom: 1px solid var(--border);
    transform: translateY(-120%);
    transition: var(--transition);
  }

  .navbar-links.open {
    transform: translateY(0);
  }

  .navbar-toggle {
    display: flex;
  }

  .features-grid,
  .steps-container,
  .data-grid {
    grid-template-columns: 1fr;
  }
}

/* ===== Animations ===== */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

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