/* Variational — smartphone advantages site */
:root {
  --bg: #0e1116;
  --bg-alt: #161b22;
  --card: #1c232d;
  --border: #2a323d;
  --text: #e6edf3;
  --muted: #9aa7b4;
  --accent: #4f8cff;
  --accent-2: #2bd9a8;
  --maxw: 1080px;
  --radius: 14px;
  font-size: 16px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

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

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

.container { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(14, 17, 22, 0.9);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}
.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 64px;
  gap: 16px;
  flex-wrap: wrap;
}
.brand { display: flex; align-items: center; gap: 10px; }
.brand img { width: 30px; height: 30px; border-radius: 7px; }
.brand .name { font-weight: 700; font-size: 1.2rem; letter-spacing: -0.01em; color: var(--text); }
.brand:hover { text-decoration: none; }

.main-nav { display: flex; gap: 20px; flex-wrap: wrap; }
.main-nav a { color: var(--muted); font-size: 0.95rem; font-weight: 500; }
.main-nav a:hover, .main-nav a[aria-current="page"] { color: var(--text); text-decoration: none; }

/* Hero */
.hero {
  padding: 72px 0 56px;
  background: radial-gradient(1200px 400px at 50% -10%, rgba(79,140,255,0.18), transparent 70%);
  text-align: center;
}
.hero h1 { font-size: clamp(2rem, 5vw, 3.2rem); line-height: 1.1; margin: 0 0 16px; letter-spacing: -0.02em; }
.hero p { font-size: 1.15rem; color: var(--muted); max-width: 660px; margin: 0 auto 28px; }
.hero .cta { display: inline-block; background: var(--accent); color: #fff; padding: 12px 26px; border-radius: 999px; font-weight: 600; }
.hero .cta:hover { background: #3a78ed; text-decoration: none; }

/* Sections */
section { padding: 48px 0; }
section h2 { font-size: clamp(1.5rem, 3vw, 2rem); margin: 0 0 8px; letter-spacing: -0.01em; }
.section-intro { color: var(--muted); max-width: 640px; margin: 0 0 32px; }

/* Card grid */
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 20px; }
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 26px 24px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  transition: transform .15s ease, border-color .15s ease;
}
.card:hover { transform: translateY(-3px); border-color: var(--accent); text-decoration: none; }
.card .ico { font-size: 2rem; line-height: 1; }
.card h3 { margin: 4px 0 0; font-size: 1.2rem; color: var(--text); }
.card p { margin: 0; color: var(--muted); font-size: 0.96rem; }
.card .more { margin-top: auto; color: var(--accent); font-weight: 600; font-size: 0.9rem; }

/* Article */
.article { max-width: 72ch; margin: 0 auto; padding: 48px 0; }
.article h1 { font-size: clamp(1.8rem, 4vw, 2.6rem); line-height: 1.15; margin: 0 0 8px; letter-spacing: -0.02em; }
.article .meta { color: var(--muted); font-size: 0.9rem; margin-bottom: 28px; }
.article h2 { font-size: 1.5rem; margin: 36px 0 10px; }
.article p { margin: 0 0 18px; }
.article ul, .article ol { margin: 0 0 18px; padding-left: 22px; }
.article li { margin-bottom: 8px; }
.article .lead { font-size: 1.15rem; color: var(--text); }
.callout {
  background: var(--bg-alt);
  border-left: 3px solid var(--accent-2);
  border-radius: 8px;
  padding: 16px 18px;
  margin: 0 0 24px;
  color: var(--muted);
}

/* Page wrapper for simple pages */
.page { max-width: 72ch; margin: 0 auto; padding: 48px 0; }
.page h1 { font-size: clamp(1.8rem, 4vw, 2.4rem); margin: 0 0 16px; letter-spacing: -0.01em; }
.page h2 { font-size: 1.3rem; margin: 28px 0 8px; }
.page p { margin: 0 0 16px; }

/* Contact */
.contact-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 20px; margin: 24px 0; }
.contact-grid .card h3 { font-size: 1rem; }
form.contact-form { display: flex; flex-direction: column; gap: 14px; max-width: 520px; margin-top: 8px; }
form.contact-form label { font-weight: 600; font-size: 0.9rem; }
form.contact-form input, form.contact-form textarea {
  width: 100%; background: var(--bg-alt); border: 1px solid var(--border);
  border-radius: 10px; padding: 11px 13px; color: var(--text); font: inherit;
}
form.contact-form textarea { min-height: 130px; resize: vertical; }
form.contact-form button {
  align-self: flex-start; background: var(--accent); color: #fff; border: 0;
  padding: 11px 24px; border-radius: 999px; font-weight: 600; cursor: pointer; font: inherit;
}
form.contact-form button:hover { background: #3a78ed; }

/* Footer */
.site-footer { border-top: 1px solid var(--border); background: var(--bg-alt); margin-top: 40px; }
.site-footer .container { padding: 36px 20px; display: flex; flex-wrap: wrap; gap: 24px; justify-content: space-between; }
.site-footer .f-brand { max-width: 280px; }
.site-footer .f-brand .name { font-weight: 700; color: var(--text); }
.site-footer .f-brand p { color: var(--muted); font-size: 0.9rem; margin: 8px 0 0; }
.site-footer nav { display: flex; flex-direction: column; gap: 8px; }
.site-footer nav strong { color: var(--text); font-size: 0.85rem; text-transform: uppercase; letter-spacing: 0.05em; margin-bottom: 4px; }
.site-footer nav a { color: var(--muted); font-size: 0.92rem; }
.site-footer nav a:hover { color: var(--text); }
.copyright { border-top: 1px solid var(--border); color: var(--muted); font-size: 0.85rem; text-align: center; padding: 18px 20px; }

@media (max-width: 640px) {
  .site-header .container { min-height: auto; padding-top: 12px; padding-bottom: 12px; }
  .main-nav { gap: 14px; }
  .hero { padding: 48px 0 36px; }
}