/* ========================================
   CSS Variables & Reset
   ======================================== */

:root {
  /* Light mode colors */
  --bg-gradient-start: #667eea;
  --bg-gradient-end: #764ba2;
  --text-primary: #1a202c;
  --text-secondary: #4a5568;
  --text-light: #718096;
  --card-bg: rgba(255, 255, 255, 0.95);
  --card-shadow: rgba(0, 0, 0, 0.1);
  --btn-primary-bg: #5a67d8;
  --btn-primary-hover: #4c51bf;
  --btn-secondary-bg: rgba(255, 255, 255, 0.2);
  --btn-secondary-hover: rgba(255, 255, 255, 0.3);
  --header-bg: rgba(255, 255, 255, 0.1);
  --footer-bg: rgba(0, 0, 0, 0.1);
  --link-color: #5a67d8;
  --link-hover: #4c51bf;

  /* Spacing & typography */
  --font-system: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", "Liberation Sans", sans-serif;
  --container-max: 1200px;
  --radius: 12px;
  --radius-sm: 8px;
  --transition: 0.3s ease;
}

/* Dark mode */
@media (prefers-color-scheme: dark) {
  :root {
    --bg-gradient-start: #1a202c;
    --bg-gradient-end: #2d3748;
    --text-primary: #f7fafc;
    --text-secondary: #e2e8f0;
    --text-light: #cbd5e0;
    --card-bg: rgba(45, 55, 72, 0.8);
    --card-shadow: rgba(0, 0, 0, 0.3);
    --btn-primary-bg: #667eea;
    --btn-primary-hover: #5a67d8;
    --btn-secondary-bg: rgba(255, 255, 255, 0.1);
    --btn-secondary-hover: rgba(255, 255, 255, 0.2);
    --header-bg: rgba(0, 0, 0, 0.2);
    --footer-bg: rgba(0, 0, 0, 0.3);
    --link-color: #90cdf4;
    --link-hover: #63b3ed;
  }
}

/* Reset & base styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

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

body {
  font-family: var(--font-system);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: linear-gradient(135deg, var(--bg-gradient-start) 0%, var(--bg-gradient-end) 100%);
  background-attachment: fixed;
  position: relative;
}

/* Subtle animated shimmer */
@media (prefers-reduced-motion: no-preference) {
  body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(
      135deg,
      transparent 0%,
      rgba(255, 255, 255, 0.05) 50%,
      transparent 100%
    );
    background-size: 200% 200%;
    animation: shimmer 15s ease infinite;
    pointer-events: none;
    z-index: 0;
  }

  @keyframes shimmer {
    0% { background-position: 0% 0%; }
    50% { background-position: 100% 100%; }
    100% { background-position: 0% 0%; }
  }
}

/* Screen reader only */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

/* ========================================
   Container & Layout
   ======================================== */

.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 1.5rem;
  width: 100%;
  position: relative;
  z-index: 1;
}

main {
  flex: 1;
  position: relative;
  z-index: 1;
}

/* ========================================
   Header
   ======================================== */

header {
  background: var(--header-bg);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  padding: 1rem 0;
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 2rem;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  color: var(--text-primary);
}

.logo img {
  display: block;
  filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.1));
}

.logo-text {
  font-size: 1.25rem;
  font-weight: 600;
  color: white;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.nav-list {
  display: flex;
  gap: 2rem;
  list-style: none;
  align-items: center;
}

.nav-list a {
  color: white;
  text-decoration: none;
  font-weight: 500;
  font-size: 0.95rem;
  transition: opacity var(--transition);
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.2);
}

.nav-list a:hover,
.nav-list a:focus {
  opacity: 0.8;
  outline: 2px solid rgba(255, 255, 255, 0.5);
  outline-offset: 4px;
  border-radius: 4px;
}

@media (max-width: 768px) {
  .nav-list {
    gap: 1rem;
  }

  .nav-list a {
    font-size: 0.85rem;
  }
}

/* ========================================
   Hero Section
   ======================================== */

.hero {
  padding: 5rem 0 4rem;
  text-align: center;
}

.hero-title {
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 700;
  color: white;
  margin-bottom: 1.5rem;
  text-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
  line-height: 1.2;
}

.hero-subtitle {
  font-size: clamp(1rem, 2.5vw, 1.25rem);
  color: rgba(255, 255, 255, 0.9);
  margin-bottom: 2rem;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

.hero-subtitle p {
  margin-bottom: 0.5rem;
}

.domain-info {
  font-size: 1rem;
  color: rgba(255, 255, 255, 0.85);
  margin-bottom: 2.5rem;
  padding: 1rem 1.5rem;
  background: var(--btn-secondary-bg);
  backdrop-filter: blur(10px);
  border-radius: var(--radius-sm);
  display: inline-block;
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.domain-info strong {
  color: white;
  font-weight: 600;
}

.hero-actions {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
  margin-top: 2rem;
}

/* ========================================
   Buttons
   ======================================== */

.btn {
  display: inline-block;
  padding: 0.875rem 2rem;
  font-size: 1rem;
  font-weight: 600;
  text-decoration: none;
  border-radius: var(--radius-sm);
  transition: all var(--transition);
  border: none;
  cursor: pointer;
  font-family: inherit;
  text-align: center;
}

.btn-primary {
  background: var(--btn-primary-bg);
  color: white;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.btn-primary:hover,
.btn-primary:focus {
  background: var(--btn-primary-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.2);
}

.btn-secondary {
  background: var(--btn-secondary-bg);
  color: white;
  border: 1px solid rgba(255, 255, 255, 0.3);
  backdrop-filter: blur(10px);
}

.btn-secondary:hover,
.btn-secondary:focus {
  background: var(--btn-secondary-hover);
  border-color: rgba(255, 255, 255, 0.4);
  transform: translateY(-2px);
}

.btn:focus {
  outline: 2px solid rgba(255, 255, 255, 0.6);
  outline-offset: 3px;
}

@media (prefers-reduced-motion: reduce) {
  .btn:hover,
  .btn:focus {
    transform: none;
  }
}

/* ========================================
   Features Section
   ======================================== */

.features {
  padding: 4rem 0;
}

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

.feature-card {
  background: var(--card-bg);
  backdrop-filter: blur(10px);
  border-radius: var(--radius);
  padding: 2rem;
  box-shadow: 0 8px 24px var(--card-shadow);
  transition: transform var(--transition), box-shadow var(--transition);
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.feature-card:hover,
.feature-card:focus-within {
  transform: translateY(-4px);
  box-shadow: 0 12px 32px var(--card-shadow);
}

@media (prefers-reduced-motion: reduce) {
  .feature-card:hover,
  .feature-card:focus-within {
    transform: none;
  }
}

.feature-icon {
  width: 48px;
  height: 48px;
  margin-bottom: 1.25rem;
  color: var(--btn-primary-bg);
}

.feature-title {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.75rem;
}

.feature-description {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ========================================
   Footer
   ======================================== */

footer {
  background: var(--footer-bg);
  backdrop-filter: blur(10px);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding: 2rem 0;
  margin-top: 4rem;
  color: rgba(255, 255, 255, 0.8);
  position: relative;
  z-index: 1;
}

.footer-content {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.5rem;
}

.footer-links {
  display: flex;
  gap: 2rem;
  list-style: none;
  flex-wrap: wrap;
  justify-content: center;
}

.footer-links a {
  color: rgba(255, 255, 255, 0.8);
  text-decoration: none;
  font-size: 0.9rem;
  transition: color var(--transition);
}

.footer-links a:hover,
.footer-links a:focus {
  color: white;
  text-decoration: underline;
  outline: 2px solid rgba(255, 255, 255, 0.5);
  outline-offset: 4px;
  border-radius: 4px;
}

.copyright {
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.6);
  text-align: center;
}

@media (max-width: 640px) {
  .footer-links {
    flex-direction: column;
    gap: 1rem;
    text-align: center;
  }
}