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

:root {
  --color-bg: #ffffff;
  --color-text: #0f172a;
  --color-text-secondary: #475569;
  --color-text-muted: #64748b;
  --color-primary: #2563eb;
  --color-primary-light: #3b82f6;
  --color-primary-dark: #1d4ed8;
  --color-accent: #0ea5e9;
  --color-surface: #f8fafc;
  --color-surface-elevated: #ffffff;
  --color-border: #e2e8f0;
  --color-border-light: #f1f5f9;
  --max-width: 1080px;
  --max-width-narrow: 780px;
  --radius: 16px;
  --radius-sm: 10px;
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.04), 0 1px 2px rgba(0, 0, 0, 0.02);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.06), 0 1px 4px rgba(0, 0, 0, 0.04);
  --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.08), 0 4px 12px rgba(0, 0, 0, 0.04);
  --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
  font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

a:hover {
  color: var(--color-primary-dark);
}

/* ---- Header ---- */
header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.82);
  backdrop-filter: blur(16px) saturate(1.8);
  -webkit-backdrop-filter: blur(16px) saturate(1.8);
  border-bottom: 1px solid rgba(226, 232, 240, 0.6);
  padding: 0 2.5rem;
  height: 64px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 100%;
}

header .logo {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--color-text);
  text-decoration: none;
  letter-spacing: -0.025em;
}

header nav {
  display: flex;
  gap: 2rem;
  align-items: center;
}

header nav a {
  color: var(--color-text-secondary);
  text-decoration: none;
  font-size: 0.875rem;
  font-weight: 500;
  transition: color var(--transition);
}

header nav a:hover {
  color: var(--color-text);
}

.lang-switch {
  font-size: 0.8rem;
  font-weight: 600;
  padding: 0.3rem 0.7rem;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  color: var(--color-text-muted);
  text-decoration: none;
  transition: all var(--transition);
  letter-spacing: 0.02em;
}

.lang-switch:hover {
  border-color: var(--color-primary-light);
  color: var(--color-primary);
  background: rgba(37, 99, 235, 0.04);
}

/* ---- Hero ---- */
.hero {
  position: relative;
  text-align: center;
  padding: 8rem 2rem 7rem;
  background:
    radial-gradient(circle at 20% 50%, rgba(37, 99, 235, 0.06) 0%, transparent 50%),
    radial-gradient(circle at 80% 50%, rgba(14, 165, 233, 0.06) 0%, transparent 50%),
    linear-gradient(180deg, #eef2ff 0%, #f8fafc 40%, var(--color-bg) 100%);
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: radial-gradient(circle, rgba(37, 99, 235, 0.08) 1px, transparent 1px);
  background-size: 32px 32px;
  mask-image: radial-gradient(ellipse 60% 60% at 50% 40%, black 20%, transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse 60% 60% at 50% 40%, black 20%, transparent 70%);
  pointer-events: none;
}

.hero::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent 0%, var(--color-border) 50%, transparent 100%);
}

.hero h1 {
  font-size: 3.75rem;
  font-weight: 800;
  line-height: 1.08;
  letter-spacing: -0.04em;
  margin-bottom: 1.5rem;
  position: relative;
  background: linear-gradient(135deg, var(--color-text) 0%, var(--color-primary-dark) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero p {
  font-size: 1.15rem;
  color: var(--color-text-secondary);
  max-width: 520px;
  margin: 0 auto 2.5rem;
  position: relative;
  line-height: 1.75;
}

.hero-cta {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.85rem 2rem;
  background: var(--color-primary);
  color: #fff;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: 50px;
  text-decoration: none;
  position: relative;
  transition: all var(--transition);
  box-shadow: 0 4px 16px rgba(37, 99, 235, 0.3);
}

.hero-cta:hover {
  background: var(--color-primary-dark);
  color: #fff;
  transform: translateY(-2px);
  box-shadow: 0 6px 24px rgba(37, 99, 235, 0.4);
}

.hero-cta svg {
  width: 18px;
  height: 18px;
  transition: transform var(--transition);
}

.hero-cta:hover svg {
  transform: translateX(3px);
}

/* ---- Sections ---- */
.section {
  padding: 6rem 2rem;
  max-width: var(--max-width);
  margin: 0 auto;
}

.section--alt {
  background: var(--color-surface);
  max-width: 100%;
  padding: 6rem 2rem;
  position: relative;
}

.section--alt::before,
.section--alt::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent 0%, var(--color-border) 50%, transparent 100%);
}

.section--alt::before { top: 0; }
.section--alt::after { bottom: 0; }

.section--alt .section-inner {
  max-width: var(--max-width);
  margin: 0 auto;
}

.section-label {
  display: inline-block;
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-primary);
  margin-bottom: 0.75rem;
  padding: 0.3rem 0.8rem;
  background: rgba(37, 99, 235, 0.06);
  border-radius: 20px;
}

.section h2,
.section--alt h2 {
  font-size: 2.1rem;
  font-weight: 800;
  letter-spacing: -0.025em;
  margin-bottom: 1rem;
  line-height: 1.2;
}

.section > p,
.section--alt .section-inner > p {
  margin-bottom: 1rem;
  color: var(--color-text-secondary);
  font-size: 1.05rem;
  max-width: 640px;
}

/* ---- Features ---- */
.features {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.25rem;
  margin-top: 3rem;
}

.feature {
  background: var(--color-surface-elevated);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 2.25rem 2rem;
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}

.feature::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--color-primary), var(--color-accent));
  opacity: 0;
  transition: opacity var(--transition);
}

.feature:hover {
  border-color: rgba(37, 99, 235, 0.2);
  box-shadow: var(--shadow-md);
  transform: translateY(-3px);
}

.feature:hover::before {
  opacity: 1;
}

.feature-icon {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-sm);
  background: linear-gradient(135deg, rgba(37, 99, 235, 0.1) 0%, rgba(14, 165, 233, 0.1) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.5rem;
}

.feature-icon svg {
  width: 24px;
  height: 24px;
}

.feature h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 0.6rem;
  letter-spacing: -0.015em;
}

.feature p {
  font-size: 0.925rem;
  color: var(--color-text-muted);
  margin: 0;
  line-height: 1.7;
}

/* ---- Contact ---- */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.25rem;
  margin-top: 2.5rem;
}

.contact-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 2rem 2.25rem;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.contact-card:hover {
  border-color: rgba(37, 99, 235, 0.15);
  box-shadow: var(--shadow-sm);
}

.contact-card h3 {
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-muted);
  margin-bottom: 1.25rem;
}

.contact-info {
  list-style: none;
}

.contact-info li {
  padding: 0.3rem 0;
  color: var(--color-text-secondary);
  font-size: 0.95rem;
}

.contact-info li strong {
  color: var(--color-text);
  font-weight: 600;
}

.contact-info a {
  color: var(--color-primary);
  text-decoration: none;
  font-weight: 500;
}

.contact-info a:hover {
  text-decoration: underline;
}

/* ---- Footer ---- */
footer {
  border-top: 1px solid var(--color-border);
  padding: 3rem 2rem;
  text-align: center;
  background: var(--color-surface);
}

footer nav {
  margin-bottom: 1.5rem;
  display: flex;
  justify-content: center;
  gap: 2rem;
  flex-wrap: wrap;
}

footer nav a {
  color: var(--color-text-muted);
  text-decoration: none;
  font-size: 0.85rem;
  font-weight: 500;
  transition: color var(--transition);
}

footer nav a:hover {
  color: var(--color-text);
}

footer p {
  font-size: 0.8rem;
  color: var(--color-text-muted);
}

/* ---- Policy pages ---- */
.policy {
  max-width: var(--max-width-narrow);
  margin: 0 auto;
  padding: 4rem 2rem 5rem;
}

.policy h1 {
  font-size: 2.25rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  margin-bottom: 0.5rem;
}

.policy .updated {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  margin-bottom: 2.5rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--color-border);
}

.policy h2 {
  font-size: 1.2rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin-top: 2.5rem;
  margin-bottom: 0.75rem;
  color: var(--color-text);
}

.policy p {
  margin-bottom: 1rem;
  color: var(--color-text-secondary);
  font-size: 0.95rem;
  line-height: 1.75;
}

.policy ul {
  margin-bottom: 1rem;
  padding-left: 1.25rem;
  color: var(--color-text-secondary);
}

.policy li {
  margin-bottom: 0.4rem;
  font-size: 0.95rem;
  padding-left: 0.25rem;
  line-height: 1.7;
}

.policy a {
  color: var(--color-primary);
  text-decoration: none;
  font-weight: 500;
}

.policy a:hover {
  text-decoration: underline;
}

/* ---- Responsive ---- */
@media (max-width: 768px) {
  header {
    padding: 0 1.25rem;
  }

  header nav {
    gap: 1.25rem;
  }

  .hero {
    padding: 5rem 1.5rem 4.5rem;
  }

  .hero h1 {
    font-size: 2.25rem;
  }

  .hero p {
    font-size: 1.05rem;
    margin-bottom: 2rem;
  }

  .features {
    grid-template-columns: 1fr;
    gap: 1rem;
  }

  .contact-grid {
    grid-template-columns: 1fr;
    gap: 1rem;
  }

  .section,
  .section--alt {
    padding: 4rem 1.25rem;
  }

  .policy {
    padding: 2.5rem 1.25rem 3.5rem;
  }

  .policy h1 {
    font-size: 1.75rem;
  }
}

@media (max-width: 480px) {
  header nav a:not(.lang-switch) {
    display: none;
  }

  .hero h1 {
    font-size: 1.85rem;
  }

  footer nav {
    flex-direction: column;
    gap: 0.75rem;
  }
}