:root {
  --color-bg: #ffffff;
  --color-bg-alt: #f7f8fa;
  --color-text: #16192b;
  --color-text-muted: #545b70;
  --color-border: #e5e7eb;
  --color-accent: #1d4ed8;
  --color-accent-dark: #1739a3;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --max-width: 1120px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3 {
  line-height: 1.2;
  font-weight: 700;
  margin: 0 0 0.6em;
}

p {
  margin: 0 0 1em;
  color: var(--color-text-muted);
}

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

a:hover {
  text-decoration: underline;
}

.wrap {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* Header */

.site-header {
  position: sticky;
  top: 0;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: saturate(180%) blur(8px);
  border-bottom: 1px solid var(--color-border);
  z-index: 10;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 8px;
  padding-top: 18px;
  padding-bottom: 18px;
}

.logo {
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--color-text);
  letter-spacing: -0.01em;
}

.logo:hover {
  text-decoration: none;
  color: var(--color-accent);
}

.nav {
  display: flex;
  gap: 24px;
  flex-wrap: wrap;
}

.nav a {
  color: var(--color-text-muted);
  font-size: 0.95rem;
  font-weight: 500;
}

.nav a:hover {
  color: var(--color-accent);
  text-decoration: none;
}

/* Sections */

section {
  padding: 88px 0;
}

section h2 {
  font-size: clamp(1.5rem, 1.2rem + 1.2vw, 2rem);
}

/* Hero */

.hero {
  padding-top: 110px;
  padding-bottom: 96px;
}

.hero h1 {
  font-size: clamp(2rem, 1.5rem + 2.2vw, 3.1rem);
  letter-spacing: -0.02em;
  max-width: 18ch;
}

.hero-sub {
  font-size: 1.15rem;
  max-width: 56ch;
  margin-bottom: 2em;
}

.button {
  display: inline-block;
  background: var(--color-accent);
  color: #fff;
  padding: 14px 28px;
  border-radius: 6px;
  font-weight: 600;
  font-size: 1rem;
}

.button:hover {
  background: var(--color-accent-dark);
  text-decoration: none;
}

/* Services */

.services {
  background: var(--color-bg-alt);
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
}

.service-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 40px 48px;
  margin-top: 40px;
}

.service h3 {
  font-size: 1.1rem;
  border-top: 2px solid var(--color-accent);
  padding-top: 16px;
}

.service p {
  margin: 0;
}

/* About */

.about .wrap {
  max-width: 720px;
}

/* Contact */

.contact {
  text-align: center;
}

.contact .wrap {
  max-width: 560px;
}

.contact h2 {
  margin-bottom: 0.4em;
}

.contact p {
  margin-bottom: 2em;
}

/* Footer */

.site-footer {
  border-top: 1px solid var(--color-border);
  padding: 32px 0;
}

.site-footer p {
  margin: 0;
  font-size: 0.85rem;
  color: var(--color-text-muted);
}

/* Responsive */

@media (max-width: 640px) {
  section {
    padding: 56px 0;
  }

  .hero {
    padding-top: 72px;
    padding-bottom: 64px;
  }

  .service-grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .nav {
    gap: 16px;
  }
}