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

:root {
  --primary: #667eea;
  --primary-dark: #5a67d8;
  --primary-light: #f0f0ff;
  --secondary: #764ba2;
  --text: #1a1a1a;
  --text-secondary: #666;
  --bg: #fafbff;
  --bg-alt: #f5f3ff;
  --border: #e8e8f0;
  --white: #ffffff;
  --radius: 12px;
  --radius-lg: 20px;
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.04);
  --shadow-md: 0 4px 20px rgba(0,0,0,0.08);
  --shadow-lg: 0 8px 40px rgba(0,0,0,0.12);
  --max-width: 1200px;
  --font: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: var(--font);
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--primary); text-decoration: none; }
code {
  background: var(--primary-light);
  padding: 2px 8px;
  border-radius: 4px;
  font-size: 0.9em;
  color: var(--primary-dark);
}
img { max-width: 100%; }

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

/* ==================== Navbar ==================== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  transition: box-shadow 0.3s;
}
.navbar.scrolled { box-shadow: var(--shadow-sm); }
.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}
.logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 20px;
  font-weight: 700;
  color: var(--text);
}
.logo-icon { font-size: 24px; }
.nav-links { display: flex; align-items: center; gap: 32px; }
.nav-links a {
  color: var(--text-secondary);
  font-size: 15px;
  font-weight: 500;
  transition: color 0.2s;
}
.nav-links a:hover { color: var(--primary); }
.nav-cta {
  background: var(--primary) !important;
  color: var(--white) !important;
  padding: 8px 20px;
  border-radius: 8px;
  transition: background 0.2s !important;
}
.nav-cta:hover { background: var(--primary-dark) !important; }

.mobile-menu-btn {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}
.mobile-menu-btn span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: 0.3s;
}

/* ==================== Hero ==================== */
.hero {
  padding: 140px 0 80px;
  text-align: center;
  background: linear-gradient(180deg, var(--white) 0%, var(--bg-alt) 100%);
}
.hero-badge {
  display: inline-block;
  background: var(--primary-light);
  color: var(--primary);
  padding: 6px 18px;
  border-radius: 20px;
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 28px;
  border: 1px solid rgba(102,126,234,0.2);
}
.hero-title {
  font-size: 52px;
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 24px;
  letter-spacing: -0.02em;
}
.highlight {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero-subtitle {
  font-size: 18px;
  color: var(--text-secondary);
  max-width: 680px;
  margin: 0 auto 40px;
  line-height: 1.8;
}
.hero-actions { display: flex; gap: 16px; justify-content: center; margin-bottom: 40px; }
.hero-tags { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }
.tag {
  background: var(--white);
  border: 1px solid var(--border);
  padding: 8px 16px;
  border-radius: 20px;
  font-size: 14px;
  color: var(--text-secondary);
}

/* ==================== Hero Showcase ==================== */
.hero-showcase {
  margin-top: 48px;
  padding: 0 24px;
}
.showcase-browser {
  background: #1e1e2e;
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 20px 60px rgba(0,0,0,0.25), 0 0 0 1px rgba(255,255,255,0.05);
  max-width: 960px;
  margin: 0 auto;
}
.browser-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 16px;
  background: #181825;
  border-bottom: 1px solid rgba(255,255,255,0.06);
}
.dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
}
.dot.red { background: #ff5f57; }
.dot.yellow { background: #febc2e; }
.dot.green { background: #28c840; }
.browser-title {
  margin-left: 12px;
  color: rgba(255,255,255,0.5);
  font-size: 13px;
  font-family: var(--font);
}
.showcase-img {
  width: 100%;
  display: block;
}

/* ==================== Buttons ==================== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  border-radius: 10px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
  border: 2px solid transparent;
  text-decoration: none;
}
.btn-lg { padding: 14px 36px; font-size: 17px; }
.btn-primary {
  background: var(--primary);
  color: var(--white);
  border-color: var(--primary);
}
.btn-primary:hover {
  background: var(--primary-dark);
  border-color: var(--primary-dark);
  transform: translateY(-1px);
  box-shadow: 0 4px 16px rgba(102,126,234,0.3);
}
.btn-outline {
  background: transparent;
  color: var(--text);
  border-color: var(--border);
}
.btn-outline:hover {
  border-color: var(--primary);
  color: var(--primary);
  transform: translateY(-1px);
}

/* ==================== Section Titles ==================== */
.section-title {
  font-size: 36px;
  font-weight: 800;
  text-align: center;
  margin-bottom: 12px;
  letter-spacing: -0.01em;
}
.section-desc {
  text-align: center;
  color: var(--text-secondary);
  font-size: 17px;
  margin-bottom: 48px;
}

/* ==================== Concept ==================== */
.concept {
  padding: 80px 0;
}
.concept-card {
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 48px;
  text-align: center;
  box-shadow: var(--shadow-sm);
}
.concept-icon { font-size: 48px; margin-bottom: 20px; }
.concept-card h2 { font-size: 24px; font-weight: 700; margin-bottom: 16px; }
.concept-card p {
  color: var(--text-secondary);
  font-size: 16px;
  line-height: 1.8;
  max-width: 800px;
  margin: 0 auto 12px;
}

/* ==================== Painpoints ==================== */
.painpoints {
  padding: 80px 0;
  background: var(--bg-alt);
}
.pain-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  max-width: 900px;
  margin: 0 auto;
}
.pain-card {
  background: var(--white);
  border-radius: var(--radius-lg);
  padding: 36px;
  box-shadow: var(--shadow-sm);
}
.pain-label {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 20px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--border);
}
.pain-card.before .pain-label { color: #e53e3e; }
.pain-card.after .pain-label { color: #38a169; }
.pain-card ul { list-style: none; }
.pain-card li {
  padding: 10px 0;
  border-bottom: 1px solid var(--border);
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.6;
}
.pain-card li:last-child { border-bottom: none; }
.pain-card.after li { color: var(--text); }

/* ==================== Features ==================== */
.features {
  padding: 80px 0;
}
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}
.feature-card {
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  position: relative;
  transition: all 0.3s;
  box-shadow: var(--shadow-sm);
}
.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: rgba(102,126,234,0.3);
}
.feature-card.featured {
  border-color: var(--primary);
  background: var(--primary-light);
}
.feature-badge {
  position: absolute;
  top: 16px;
  right: 16px;
  background: #38a169;
  color: white;
  padding: 3px 10px;
  border-radius: 12px;
  font-size: 12px;
  font-weight: 600;
}
.feature-badge.pro {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
}
.feature-icon { font-size: 36px; margin-bottom: 12px; }
.feature-card h3 { font-size: 18px; font-weight: 700; margin-bottom: 8px; }
.feature-tagline {
  color: var(--text-secondary);
  font-size: 14px;
  margin-bottom: 16px;
  line-height: 1.5;
}
.feature-screenshots {
  display: flex;
  gap: 8px;
  margin-bottom: 16px;
  border-radius: 8px;
  overflow: hidden;
  background: #f8f8fa;
}
.feature-img {
  width: 100%;
  height: auto;
  display: block;
  border-radius: 6px;
  border: 1px solid var(--border);
}
.feature-screenshots .feature-img:only-child {
  border-radius: 8px;
}
.feature-list { list-style: none; }
.feature-list li {
  padding: 4px 0;
  font-size: 13px;
  color: var(--text-secondary);
  padding-left: 16px;
  position: relative;
}
.feature-list li::before {
  content: "•";
  position: absolute;
  left: 0;
  color: var(--primary);
  font-weight: 700;
}

/* ==================== Highlight Stats ==================== */
.highlight-section {
  padding: 60px 0;
  background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
  color: white;
}
.highlight-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
  text-align: center;
}
.highlight-num {
  font-size: 48px;
  font-weight: 800;
  margin-bottom: 8px;
}
.highlight-label {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 4px;
}
.highlight-desc {
  font-size: 14px;
  opacity: 0.8;
}

/* ==================== Compare ==================== */
.compare {
  padding: 80px 0;
  background: var(--bg-alt);
}
.compare-table-wrap {
  max-width: 900px;
  margin: 0 auto;
  background: var(--white);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border);
}
.compare-table {
  width: 100%;
  border-collapse: collapse;
}
.compare-table th,
.compare-table td {
  padding: 16px 24px;
  text-align: left;
  border-bottom: 1px solid var(--border);
  font-size: 15px;
}
.compare-table th {
  background: var(--primary-light);
  font-weight: 700;
  color: var(--text);
}
.compare-table th:nth-child(2) { color: #38a169; }
.compare-table th:nth-child(3) {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: white;
}
.compare-table tr:last-child td { border-bottom: none; }
.compare-table tr:hover td { background: rgba(102,126,234,0.03); }

/* ==================== Use Cases ==================== */
.use-cases {
  padding: 80px 0;
}
.use-case-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}
.use-case-card {
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px 24px;
  text-align: center;
  transition: all 0.3s;
  box-shadow: var(--shadow-sm);
}
.use-case-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}
.use-case-icon { font-size: 40px; margin-bottom: 16px; }
.use-case-card h3 { font-size: 18px; font-weight: 700; margin-bottom: 8px; }
.use-case-card p { color: var(--text-secondary); font-size: 14px; line-height: 1.7; }

/* ==================== Advantages ==================== */
.advantages {
  padding: 80px 0;
  background: var(--bg-alt);
}
.adv-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}
.adv-item {
  background: var(--white);
  border-radius: var(--radius);
  padding: 32px 24px;
  text-align: center;
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
}
.adv-icon { font-size: 36px; margin-bottom: 16px; }
.adv-item h3 { font-size: 17px; font-weight: 700; margin-bottom: 8px; }
.adv-item p { color: var(--text-secondary); font-size: 14px; line-height: 1.7; }

/* ==================== CTA ==================== */
.cta {
  padding: 80px 0;
}
.cta-card {
  background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
  border-radius: var(--radius-lg);
  padding: 60px;
  text-align: center;
  color: white;
}
.cta-icon { font-size: 56px; margin-bottom: 20px; }
.cta-card h2 {
  font-size: 32px;
  font-weight: 800;
  margin-bottom: 16px;
}
.cta-card p {
  font-size: 17px;
  opacity: 0.9;
  margin-bottom: 32px;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}
.cta-actions { display: flex; gap: 16px; justify-content: center; margin-bottom: 24px; }
.cta-actions .btn-primary {
  background: white;
  color: var(--primary);
  border-color: white;
}
.cta-actions .btn-primary:hover {
  background: rgba(255,255,255,0.9);
  transform: translateY(-1px);
}
.cta-actions .btn-outline {
  border-color: rgba(255,255,255,0.5);
  color: white;
}
.cta-actions .btn-outline:hover {
  border-color: white;
  background: rgba(255,255,255,0.1);
}
.cta-note { font-size: 14px; opacity: 0.7; }

/* ==================== Footer ==================== */
.footer {
  padding: 32px 0;
  border-top: 1px solid var(--border);
  background: var(--white);
}
.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.footer-brand {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  font-size: 16px;
}
.footer-links { display: flex; gap: 24px; }
.footer-links a {
  color: var(--text-secondary);
  font-size: 14px;
  transition: color 0.2s;
}
.footer-links a:hover { color: var(--primary); }
.footer-copy { color: var(--text-secondary); font-size: 13px; }

/* ==================== Responsive ==================== */
@media (max-width: 1024px) {
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
  .use-case-grid { grid-template-columns: repeat(2, 1fr); }
  .adv-grid { grid-template-columns: repeat(2, 1fr); }
  .highlight-grid { grid-template-columns: repeat(2, 1fr); gap: 24px; }
}

@media (max-width: 768px) {
  .nav-links { display: none; }
  .mobile-menu-btn { display: flex; }
  .nav-links.active {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: white;
    padding: 20px 24px;
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow-md);
    gap: 16px;
  }
  .hero { padding: 120px 0 60px; }
  .hero-title { font-size: 32px; }
  .hero-subtitle { font-size: 16px; }
  .hero-actions { flex-direction: column; align-items: center; }
  .hero-showcase { margin-top: 32px; }
  .showcase-browser { border-radius: 8px; }
  .section-title { font-size: 28px; }
  .feature-grid { grid-template-columns: 1fr; }
  .feature-screenshots { flex-direction: column; }
  .pain-grid { grid-template-columns: 1fr; }
  .use-case-grid { grid-template-columns: 1fr; }
  .adv-grid { grid-template-columns: 1fr; }
  .highlight-grid { grid-template-columns: repeat(2, 1fr); }
  .compare-table-wrap { overflow-x: auto; }
  .compare-table { min-width: 600px; }
  .cta-card { padding: 40px 24px; }
  .cta-actions { flex-direction: column; align-items: center; }
  .footer-inner { flex-direction: column; gap: 16px; text-align: center; }
}