:root {
  --bg: #0b0f16;
  --panel: #151b25;
  --text: #eef1f6;
  --muted: #a4adbb;
  --brand1: #ff8a33;
  --brand2: #ff3d2f;
  --line: #273042;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Hiragino Sans", "Noto Sans JP", -apple-system, BlinkMacSystemFont, sans-serif;
  background: radial-gradient(1200px 500px at 10% -10%, #2d1f15 0%, rgba(11, 15, 22, 0) 55%), var(--bg);
  color: var(--text);
  line-height: 1.65;
}

.container {
  max-width: 980px;
  margin: 0 auto;
  padding: 28px 20px 60px;
}

.topbar {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 24px;
}

.icon {
  width: 56px;
  height: 56px;
  border-radius: 14px;
}

h1 {
  margin: 0;
  font-size: 2rem;
  line-height: 1.2;
}

.subtitle {
  margin: 6px 0 0;
  color: var(--muted);
}

.hero {
  border: 1px solid var(--line);
  background: linear-gradient(135deg, rgba(255, 138, 51, 0.1), rgba(255, 61, 47, 0.08));
  border-radius: 18px;
  padding: 22px;
  margin-bottom: 24px;
}

.grid {
  display: grid;
  gap: 14px;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.card {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 16px;
}

.card h2,
.card h3 {
  margin: 0 0 10px;
  font-size: 1.05rem;
}

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

a {
  color: #85b9ff;
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.btn {
  display: inline-block;
  background: linear-gradient(100deg, var(--brand1), var(--brand2));
  color: #fff;
  padding: 10px 16px;
  border-radius: 999px;
  text-decoration: none;
  font-weight: 700;
}

.btn:hover {
  opacity: 0.92;
  text-decoration: none;
}

ul {
  margin: 0;
  padding-left: 20px;
}

footer {
  margin-top: 26px;
  color: var(--muted);
  font-size: 0.92rem;
}

@media (max-width: 600px) {
  h1 {
    font-size: 1.7rem;
  }

  .container {
    padding-top: 20px;
  }
}