:root {
  --bg: #0b0f17;
  --card: rgba(255, 255, 255, 0.06);
  --text: rgba(255, 255, 255, 0.92);
  --muted: rgba(255, 255, 255, 0.72);
  --line: rgba(255, 255, 255, 0.14);
  --link: #8bd3ff;
  --link-hover: #b8e5ff;
  --shadow: 0 12px 40px rgba(0, 0, 0, 0.5);
}

* {
  box-sizing: border-box;
}

html,
body {
  min-height: 100%;
}

body {
  margin: 0;
  padding: 28px 18px;
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, "Noto Sans", "Hiragino Sans", "Yu Gothic", "Meiryo", sans-serif;
  line-height: 1.7;
  color: var(--text);
  background:
    radial-gradient(1000px 700px at 20% 20%, rgba(99, 102, 241, 0.22), transparent 60%),
    radial-gradient(900px 600px at 85% 30%, rgba(16, 185, 129, 0.18), transparent 55%),
    radial-gradient(700px 500px at 55% 85%, rgba(56, 189, 248, 0.16), transparent 55%),
    var(--bg);
}

body > * {
  width: min(860px, 100%);
  margin-left: auto;
  margin-right: auto;
}

h1 {
  margin: 12px auto 10px;
  line-height: 1.2;
  font-size: clamp(22px, 3vw, 34px);
}

p,
ul,
nav {
  width: min(860px, 100%);
  margin-left: auto;
  margin-right: auto;
}

p {
  color: var(--muted);
}

ul {
  margin-top: 8px;
  margin-bottom: 16px;
}

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

a:hover {
  color: var(--link-hover);
  text-decoration: underline;
}

nav {
  margin-top: 8px;
  margin-bottom: 14px;
}

.global-nav {
  padding: 10px 12px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--card);
  box-shadow: var(--shadow);
}