:root {
  --black: #11121f;
  --red: #da143e;
  --red-light: #ff5a76;
  --purple: #6d3bd1;
  --text: #c9cce0;
  --muted: #8a8fae;
  --card: rgb(23 25 40 / 0.82);
  --line: #2e3358;
}

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

body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 32px;
  padding: 40px 16px;
  font: 16px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, Arial, sans-serif;
  color: var(--text);
  background-color: var(--black);
  background-image:
    url('img/plexus.svg'),
    radial-gradient(ellipse at 15% 0%, rgb(109 59 209 / 0.3), transparent 55%),
    radial-gradient(ellipse at 90% 100%, rgb(218 20 62 / 0.14), transparent 60%);
  background-size: cover, auto, auto;
  background-position: center, 0 0, 0 0;
  background-attachment: fixed;
  border-top: 4px solid;
  border-image: linear-gradient(90deg, var(--red), var(--purple)) 1;
}

a {
  color: #fff;
  text-decoration: none;
}
a:hover {
  text-decoration: underline;
}

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

/* hlavicka */
.top {
  width: 100%;
  max-width: 760px;
}
.logo {
  font: 700 28px/1 ui-monospace, "Cascadia Code", "SF Mono", Menlo, Consolas, "DejaVu Sans Mono", monospace;
  letter-spacing: -0.02em;
  color: #fff;
}
.logo:hover {
  text-decoration: none;
}
.logo b {
  color: var(--red);
}
.tagline {
  margin: 8px 0 0;
  font: 14px/1.4 ui-monospace, "Cascadia Code", "SF Mono", Menlo, Consolas, "DejaVu Sans Mono", monospace;
  color: var(--muted);
}

/* karta s kontakty */
.card {
  width: 100%;
  max-width: 760px;
  display: flex;
  align-items: center;
  gap: 48px;
  padding: 48px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 20px;
  box-shadow: 0 20px 60px rgb(0 0 0 / 0.5);
  backdrop-filter: blur(6px);
}

.foto {
  flex: none;
  width: 200px;
  border-radius: 50%;
  border: 4px solid transparent;
  background: linear-gradient(var(--black), var(--black)) padding-box,
              linear-gradient(135deg, var(--red), var(--purple)) border-box;
}

.info h1 {
  margin: 0 0 20px;
  font-size: 32px;
  line-height: 1.2;
  font-weight: 700;
  color: #fff;
}

.contacts {
  margin: 0;
  padding: 0;
  list-style: none;
}
.contacts li {
  display: flex;
  gap: 12px;
  padding: 6px 0;
}
.contacts span,
.billing h2 {
  min-width: 80px;
  font: 600 12px/25px ui-monospace, "Cascadia Code", "SF Mono", Menlo, Consolas, monospace;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--muted);
}
.contacts a {
  font-weight: 600;
  color: var(--red-light);
}

.billing {
  margin-top: 24px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
}
.billing h2 {
  margin: 0 0 6px;
}
.billing address {
  font-style: normal;
}
.billing p {
  margin: 8px 0 0;
}

/* paticka */
.partner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--muted);
}
.partner img {
  width: 108px;
  padding: 10px 12px 6px;
  background: #fff;
  border-radius: 14px;
  transition: transform 0.2s;
}
.partner:hover img {
  transform: scale(1.05);
}

/* mobil */
@media (max-width: 640px) {
  body {
    padding-top: 24px;
  }
  .top {
    text-align: center;
  }
  .logo {
    font-size: 22px;
  }
  .card {
    flex-direction: column;
    text-align: center;
    gap: 24px;
    padding: 32px 20px;
  }
  .foto {
    width: 160px;
  }
  .contacts li {
    flex-direction: column;
    gap: 0;
  }
}