/* ==================== RESET & GLOBAL ==================== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --bg-primary: #0f172a;
  --bg-secondary: #1e293b;
  --bg-card: #1e293b;
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --accent: #3b82f6;
  --accent-hover: #2563eb;
  --border: #334155;
  --shadow: rgba(0, 0, 0, 0.3);
}

[data-theme="light"] {
  --bg-primary: #f8fafc;
  --bg-secondary: #ffffff;
  --bg-card: #ffffff;
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --accent: #2563eb;
  --accent-hover: #1d4ed8;
  --border: #e2e8f0;
  --shadow: rgba(0, 0, 0, 0.05);
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.5;
  transition: background-color 0.3s ease, color 0.3s ease;
}

/* ==================== CONTAINER ==================== */
.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ==================== HEADER ==================== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: var(--bg-primary);
  border-bottom: 1px solid var(--border);
  z-index: 100;
  backdrop-filter: blur(10px);
  background: rgba(var(--bg-primary-rgb, 15, 23, 42), 0.9);
}

.header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 0;
}

.logo {
  font-size: 28px;
  font-weight: 800;
  letter-spacing: -0.02em;
  text-decoration: none;
  color: var(--text-primary);
}

.logo span {
  color: var(--accent);
}

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

.nav-link {
  text-decoration: none;
  color: var(--text-secondary);
  transition: color 0.2s;
  font-weight: 500;
}

.nav-link:hover {
  color: var(--accent);
}

.btn-login {
  padding: 8px 20px;
  border-radius: 40px;
  background: var(--accent);
  color: white;
  text-decoration: none;
  font-weight: 600;
  transition: background 0.2s, transform 0.1s;
  border: none;
  cursor: pointer;
}

.btn-login:hover {
  background: var(--accent-hover);
  transform: translateY(-1px);
}

.theme-toggle {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 40px;
  padding: 8px 12px;
  cursor: pointer;
  font-size: 18px;
  transition: 0.2s;
}

/* ==================== HERO SECTION ==================== */
.hero {
  padding: 120px 0 80px;
  min-height: 100vh;
  display: flex;
  align-items: center;
}

.hero-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.hero-text h1 {
  font-size: 56px;
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.02em;
  margin-bottom: 24px;
}

.hero-text h1 span {
  color: var(--accent);
}

.hero-text p {
  font-size: 18px;
  color: var(--text-secondary);
  margin-bottom: 32px;
  max-width: 500px;
}

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

.btn-primary {
  padding: 14px 32px;
  border-radius: 48px;
  background: var(--accent);
  color: white;
  text-decoration: none;
  font-weight: 600;
  transition: background 0.2s, transform 0.1s;
  display: inline-block;
}

.btn-primary:hover {
  background: var(--accent-hover);
  transform: translateY(-2px);
}

.btn-secondary {
  padding: 14px 32px;
  border-radius: 48px;
  background: transparent;
  color: var(--text-primary);
  text-decoration: none;
  font-weight: 600;
  border: 1px solid var(--border);
  transition: border-color 0.2s;
}

.btn-secondary:hover {
  border-color: var(--accent);
}

.hero-image {
  background: linear-gradient(135deg, var(--accent), #1e40af);
  border-radius: 32px;
  padding: 40px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero-image svg {
  width: 100%;
  max-width: 300px;
  height: auto;
}

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

.section-title {
  font-size: 36px;
  font-weight: 700;
  text-align: center;
  margin-bottom: 16px;
}

.section-subtitle {
  text-align: center;
  color: var(--text-secondary);
  margin-bottom: 48px;
  font-size: 18px;
}

/* ==================== CARDS GRID ==================== */
.grid-3 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 32px;
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 24px;
  padding: 32px;
  transition: transform 0.2s, box-shadow 0.2s;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 24px var(--shadow);
}

.card-icon {
  width: 56px;
  height: 56px;
  background: rgba(59, 130, 246, 0.1);
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 24px;
}

.card-icon svg {
  width: 32px;
  height: 32px;
  stroke: var(--accent);
  stroke-width: 1.5;
}

.card h3 {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 12px;
}

.card p {
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ==================== ADVANTAGES ==================== */
.advantages {
  background: var(--bg-secondary);
}

.grid-2 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 32px;
}

.advantage-item {
  display: flex;
  gap: 16px;
  align-items: flex-start;
}

.advantage-icon {
  background: var(--accent);
  border-radius: 12px;
  padding: 12px;
  flex-shrink: 0;
}

.advantage-icon svg {
  display: block;
}

/* ==================== CONTACTS ==================== */
.contact-link {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.2s;
}

.contact-link:hover {
  color: var(--accent-hover);
  text-decoration: underline;
}

/* ==================== FOOTER ==================== */
.footer {
  border-top: 1px solid var(--border);
  padding: 48px 0 32px;
  margin-top: 40px;
}

.footer-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 24px;
}

.footer-logo {
  font-size: 20px;
  font-weight: 700;
}

.social-links {
  display: flex;
  gap: 24px;
}

.social-links a {
  color: var(--text-secondary);
  text-decoration: none;
  transition: color 0.2s;
}

.social-links a:hover {
  color: var(--accent);
}

.copyright {
  text-align: center;
  color: var(--text-secondary);
  font-size: 14px;
  margin-top: 32px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
}

/* ==================== MOBILE MENU ==================== */
.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  font-size: 28px;
  cursor: pointer;
  color: var(--text-primary);
}

/* ==================== MEDIA QUERIES ==================== */
@media (max-width: 768px) {
  .mobile-menu-btn {
    display: block;
  }
  
  .nav {
    display: none;
    flex-direction: column;
    position: absolute;
    top: 70px;
    left: 0;
    right: 0;
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border);
    padding: 20px;
    gap: 20px;
  }
  
  .nav.active {
    display: flex;
  }
  
  .hero-content {
    grid-template-columns: 1fr;
    text-align: center;
  }
  
  .hero-text h1 {
    font-size: 40px;
  }
  
  .hero-text p {
    margin-left: auto;
    margin-right: auto;
  }
  
  .hero-buttons {
    justify-content: center;
  }
  
  .section-title {
    font-size: 28px;
  }
  
  .footer-content {
    flex-direction: column;
    text-align: center;
  }
  
  .grid-2, .grid-3 {
    grid-template-columns: 1fr;
  }
}