:root {
  --bg: #0a0f1c;
  --surface: #121a2d;
  --surface-2: #1a2540;
  --border: #2a3856;
  --text: #f3f6fb;
  --muted: #9fb0ce;
  --accent: #4b77e8;
  --accent-hover: #6f98f2;
  --product-accent: #ff7a1a;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
}

* { box-sizing: border-box; }

html, body { margin: 0; padding: 0; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}

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

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

h1, h2, h3 { margin: 0 0 0.5em; line-height: 1.15; letter-spacing: -0.01em; }
h1 { font-size: clamp(2.2rem, 5vw, 3.6rem); font-weight: 800; }
h2 { font-size: clamp(1.4rem, 3vw, 1.9rem); font-weight: 700; }
h3 { font-size: 1.25rem; font-weight: 700; }
p  { margin: 0 0 1em; color: var(--text); }

/* Layout */
.nav, main, .foot { max-width: 880px; margin: 0 auto; padding: 0 24px; }

.nav {
  display: flex; align-items: center; justify-content: space-between;
  padding-top: 28px; padding-bottom: 28px;
}
.brand { display: inline-flex; align-items: center; gap: 12px; color: var(--text); }
.brand img { border-radius: 50%; background: #fff; padding: 3px; }
.brand__name { font-weight: 800; letter-spacing: 0.02em; font-size: 1.05rem; }
.nav__cta {
  font-size: 0.95rem; color: var(--muted);
  padding: 8px 14px; border: 1px solid var(--border); border-radius: 999px;
}
.nav__cta:hover { color: var(--text); border-color: var(--accent); }

/* Hero */
.hero {
  padding: 56px 0 40px;
  border-bottom: 1px solid var(--border);
}
.hero__lede {
  font-size: 1.15rem; color: var(--muted); max-width: 54ch; margin-top: 0.5em;
}
.hero__actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 28px; }

/* About */
.about { padding: 48px 0; border-bottom: 1px solid var(--border); }
.about p { color: var(--muted); max-width: 64ch; font-size: 1.05rem; }

/* Product */
.product { padding: 48px 0 72px; }
.card {
  background: linear-gradient(180deg, var(--surface) 0%, var(--surface-2) 100%);
  border: 1px solid var(--border); border-radius: 16px; padding: 32px;
  margin-top: 24px;
}
.card__mark {
  display: inline-block; font-size: 1rem; letter-spacing: 0.02em;
  font-weight: 800; margin-bottom: 14px;
}
.vi-voice { color: var(--product-accent); }
.vi-invoicing { color: var(--text); }
.card__title { font-size: 1.5rem; }
.card__body { color: var(--muted); max-width: 60ch; font-size: 1.02rem; }

/* Buttons */
.btn {
  display: inline-block; padding: 12px 20px; border-radius: 10px;
  border: 1px solid var(--border); background: transparent; color: var(--text);
  font-weight: 600; font-size: 0.98rem; cursor: pointer;
  transition: background 120ms ease, border-color 120ms ease, color 120ms ease;
}
.btn:hover { border-color: var(--accent); color: var(--text); }
.btn--primary {
  background: var(--accent); border-color: var(--accent); color: #0a0f1c;
}
.btn--primary:hover { background: var(--accent-hover); border-color: var(--accent-hover); color: #0a0f1c; }

.product .btn--primary {
  background: var(--product-accent); border-color: var(--product-accent); color: #0a0f1c;
}
.product .btn--primary:hover {
  background: #ff9142; border-color: #ff9142;
}

/* Footer */
.foot { padding: 32px 24px 48px; border-top: 1px solid var(--border); margin-top: 0; }
.foot__row {
  display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap;
  gap: 12px; color: var(--muted); font-size: 0.95rem;
}
.foot__meta { color: var(--muted); font-size: 0.85rem; margin-top: 8px; }

@media (max-width: 520px) {
  .nav { padding-top: 20px; padding-bottom: 20px; }
  .hero { padding: 40px 0 32px; }
  .about, .product { padding: 36px 0; }
  .card { padding: 24px; }
}