* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Hiragino Kaku Gothic ProN", Meiryo, "Noto Sans JP", sans-serif;
  color: #222;
  background: #f7f7fb;
}
.container {
  max-width: 720px;
  margin: 40px auto;
  background: #fff;
  border-radius: 12px;
  box-shadow: 0 10px 30px rgba(0,0,0,.08);
  padding: 24px 28px;
}
h1 { font-size: 22px; margin: 0 0 16px; }
.row { display: grid; grid-template-columns: 180px 1fr; gap: 12px; align-items: center; margin: 10px 0; }
label { color: #555; }
input[type="text"], input[type="number"], input[type="range"] {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid #ddd;
  border-radius: 8px;
  font-size: 14px;
}
input[type="range"] { padding: 6px 0; }
button {
  grid-column: 2 / 3;
  padding: 10px 14px;
  background: #2b6ef7;
  color: #fff;
  border: none;
  border-radius: 8px;
  cursor: pointer;
}
button:hover { background: #1f56c1; }
.hint { color: #666; font-size: 12px; margin-top: 10px; }