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

:root {
  --brand-cyan: #0080a0;
  --brand-cyan-dark: #006a86;
  --brand-orange: #e06000;
  --bg: #fafbfc;
  --surface: #ffffff;
  --text: #102a31;
  --text-muted: #55717a;
  --border: #e2e9ec;
  --footer-bg: #0c1f25;
  --footer-text: #bcd6dd;
  --radius: 16px;
  --shadow: 0 1px 3px rgba(16, 42, 49, 0.08), 0 4px 16px rgba(16, 42, 49, 0.06);
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

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

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: var(--brand-cyan-dark);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.container {
  width: 100%;
  max-width: 960px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Header */
.site-header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 10;
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 8px 16px;
  padding-top: 10px;
  padding-bottom: 10px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text);
}

.brand:hover {
  text-decoration: none;
}

.brand img {
  width: 40px;
  height: 40px;
}

.main-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 18px;
  font-weight: 500;
}

.main-nav a {
  padding: 6px 2px;
  color: var(--text-muted);
  border-bottom: 2px solid transparent;
}

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

.main-nav a[aria-current="page"] {
  color: var(--brand-cyan-dark);
  border-bottom-color: var(--brand-cyan);
}

/* Layout */
main {
  padding: 40px 0 64px;
}

.hero {
  text-align: center;
  padding: 32px 0 8px;
}

.hero img {
  width: 128px;
  height: 128px;
  margin: 0 auto 20px;
}

.hero h1 {
  font-size: clamp(1.9rem, 5vw, 3rem);
  line-height: 1.15;
  margin: 0 0 12px;
  letter-spacing: -0.02em;
}

.hero .tagline {
  font-size: clamp(1.05rem, 2.5vw, 1.35rem);
  color: var(--text-muted);
  max-width: 640px;
  margin: 0 auto;
}

.hero-actions {
  margin-top: 28px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 28px;
  margin: 28px 0;
}

.card h2 {
  margin-top: 0;
  font-size: 1.5rem;
  letter-spacing: -0.01em;
}

.card p:last-child {
  margin-bottom: 0;
}

.grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
  margin: 28px 0;
}

@media (min-width: 720px) {
  .grid {
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  }
}

.grid-item {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 24px;
}

.grid-item h3 {
  margin: 0 0 8px;
  font-size: 1.15rem;
}

.grid-item p {
  margin: 0;
  color: var(--text-muted);
  font-size: 0.95rem;
}

/* Buttons */
.btn {
  display: inline-block;
  padding: 12px 22px;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.95rem;
  transition: background 0.15s ease, transform 0.1s ease;
}

.btn:active {
  transform: scale(0.98);
}

.btn-primary {
  background: var(--brand-cyan);
  color: #fff;
}

.btn-primary:hover {
  background: var(--brand-cyan-dark);
  text-decoration: none;
}

.btn-outline {
  border: 1.5px solid var(--brand-cyan);
  color: var(--brand-cyan-dark);
}

.btn-outline:hover {
  background: rgba(0, 128, 160, 0.08);
  text-decoration: none;
}

/* Article pages */
.page-head {
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 24px;
}

.page-head h1 {
  margin: 0 0 4px;
  font-size: clamp(1.6rem, 4vw, 2.2rem);
  letter-spacing: -0.02em;
}

.page-head .updated {
  color: var(--text-muted);
  font-size: 0.9rem;
}

.prose h2 {
  font-size: 1.25rem;
  margin: 28px 0 8px;
}

.prose h3 {
  font-size: 1.05rem;
  margin: 20px 0 6px;
}

.prose p {
  margin: 0 0 14px;
}

.prose ul {
  margin: 0 0 14px;
  padding-left: 22px;
}

.prose li {
  margin-bottom: 6px;
}

.callout {
  background: rgba(0, 128, 160, 0.07);
  border-left: 4px solid var(--brand-cyan);
  border-radius: 8px;
  padding: 16px 18px;
  margin: 20px 0;
}

/* Contact */
.contact {
  text-align: center;
}

.contact .mail {
  font-size: 1.1rem;
  font-weight: 600;
  word-break: break-all;
}

/* Footer */
.site-footer {
  background: var(--footer-bg);
  color: var(--footer-text);
  padding: 32px 0;
  margin-top: 32px;
}

.site-footer .container {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 24px;
}

.site-footer a {
  color: #7fd4e8;
}

.footer-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 18px;
}

@media (max-width: 560px) {
  .site-header .container {
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
  }

  .site-footer .container {
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
  }

  main {
    padding: 24px 0 40px;
  }

  .card {
    padding: 20px;
  }

  .hero img {
    width: 96px;
    height: 96px;
  }
}