:root {
  --sky-top: #5ab8f5;
  --sky-bottom: #bfe6ff;
  --card: #f2f7ff;
  --ink: #1d2b44;
  --muted: #4f5f7a;
  --accent: #2f9e57;
  --link: #1764c0;
  --line: #d5e2f3;
  color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
  :root {
    --sky-top: #0f2a47;
    --sky-bottom: #17385c;
    --card: #1c2533;
    --ink: #e8eef8;
    --muted: #a8b6cc;
    --accent: #4cd07a;
    --link: #7ab8ff;
    --line: #2d3a4f;
  }
}

* { box-sizing: border-box; }

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

body {
  margin: 0;
  min-height: 100vh;
  background: linear-gradient(180deg, var(--sky-top), var(--sky-bottom)) fixed;
  color: var(--ink);
  font: 17px/1.55 ui-rounded, "SF Pro Rounded", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}

main {
  max-width: 760px;
  margin: 0 auto;
  padding: 32px 16px 48px;
}

.card {
  background: var(--card);
  border-radius: 24px;
  padding: 24px;
  margin-bottom: 20px;
  box-shadow: 0 6px 24px rgba(0, 0, 0, 0.14);
}

.brand {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 20px;
  color: #fff;
  text-decoration: none;
}

.brand img {
  width: 56px;
  height: 56px;
  border-radius: 13px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}

.brand span {
  font-size: 28px;
  font-weight: 800;
  text-shadow: 0 2px 6px rgba(0, 0, 0, 0.25);
}

h1 { font-size: 30px; line-height: 1.2; margin: 0 0 8px; }
h2 { font-size: 21px; margin: 28px 0 8px; }
h2:first-child { margin-top: 0; }
p, ul { margin: 0 0 12px; }
li { margin-bottom: 6px; }
a { color: var(--link); }

.muted { color: var(--muted); font-size: 15px; }

.button {
  display: inline-block;
  padding: 12px 22px;
  border-radius: 16px;
  background: var(--accent);
  color: #fff;
  font-weight: 700;
  text-decoration: none;
  box-shadow: 0 4px 0 rgba(0, 0, 0, 0.2);
}

.button.disabled { opacity: 0.6; pointer-events: none; }

nav.links {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
  justify-content: center;
  font-size: 15px;
}

nav.links a { color: #fff; font-weight: 600; }

table { width: 100%; border-collapse: collapse; font-size: 15px; }
th, td { text-align: left; vertical-align: top; padding: 8px 6px; border-top: 1px solid var(--line); }
th { border-top: none; }

@media (max-width: 520px) {
  body { font-size: 16px; }
  .card { padding: 18px; border-radius: 20px; }
  h1 { font-size: 26px; }
  table, thead, tbody, tr, th, td { display: block; }
  thead { display: none; }
  td { border-top: none; padding: 2px 0; }
  tr { border-top: 1px solid var(--line); padding: 8px 0; }
}