:root {
  --bsod-blue: #0000aa;
  --bsod-cyan: #55ffff;
  --bsod-gray: #aaaaaa;
  --bsod-white: #ffffff;
  --win10-blue: #0078d7;
  --win10-ink: #f3f3f3;
}

* {
  box-sizing: border-box;
}

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

body {
  min-height: 100vh;
  background: var(--bsod-blue);
  color: var(--bsod-white);
  font-family: "Lucida Console", "Consolas", "Courier New", monospace;
  line-height: 1.45;
}

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

a:hover,
a:focus {
  text-decoration: underline;
}

.scan {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.topbar {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.85rem 1.4rem;
  background: var(--bsod-gray);
  color: var(--bsod-blue);
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.9rem 1.2rem;
}

.nav a {
  color: var(--bsod-blue);
}

.hero,
.page {
  max-width: 52rem;
  margin: 0 auto;
  padding: 2.4rem 1.4rem 3.2rem;
}

.glyph {
  font-size: 5.5rem;
  line-height: 1;
  margin: 0 0 0.6rem;
}

h1 {
  font-size: 1.7rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  margin: 0 0 1rem;
}

h2 {
  font-size: 1.05rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin: 2rem 0 0.7rem;
}

p,
li {
  font-size: 0.98rem;
}

.stop {
  margin: 1.4rem 0;
  padding: 1rem 1.1rem;
  border: 2px solid var(--bsod-white);
}

.stop code,
code {
  font-family: inherit;
  color: var(--bsod-cyan);
}

.progress {
  margin: 1.6rem 0 0.4rem;
  height: 1.1rem;
  background: #000066;
  border: 1px solid var(--bsod-white);
}

.progress > span {
  display: block;
  height: 100%;
  width: 23%;
  background: var(--bsod-cyan);
}

.quote {
  min-height: 6.5rem;
  margin: 1.5rem 0;
  padding: 1rem 1.1rem;
  background: #000066;
}

.grid {
  display: grid;
  gap: 1rem;
}

@media (min-width: 720px) {
  .grid.two {
    grid-template-columns: 1fr 1fr;
  }
}

.card {
  padding: 1rem;
  border: 1px solid var(--bsod-cyan);
}

.footer {
  margin-top: auto;
  padding: 1rem 1.4rem 1.5rem;
  color: var(--bsod-gray);
  font-size: 0.8rem;
}

.win10 {
  background: var(--win10-blue);
  color: var(--win10-ink);
}

.win10 .topbar {
  background: rgba(0, 0, 0, 0.18);
  color: var(--win10-ink);
}

.win10 .nav a {
  color: var(--win10-ink);
}

.win10 a {
  color: #fff59a;
}

.qr-slot {
  width: 7rem;
  height: 7rem;
  margin: 1.2rem 0;
  background:
    repeating-linear-gradient(90deg, #fff 0 8px, #0078d7 8px 16px),
    repeating-linear-gradient(#fff 0 8px, #0078d7 8px 16px);
  background-blend-mode: difference;
}

.rite {
  display: inline-block;
  margin: 1.2rem 0 0.4rem;
  padding: 0.85rem 1.3rem;
  border: 3px solid var(--bsod-white);
  background: var(--bsod-cyan);
  color: var(--bsod-blue);
  font-family: inherit;
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  cursor: pointer;
}

.rite:hover,
.rite:focus {
  background: var(--bsod-white);
}

.loud {
  color: var(--bsod-cyan);
  font-size: 0.9rem;
}