html, body {
  width: 100%;
  height: 100%;
  margin: 0;
  padding: 0;
  overflow: clip;
  overscroll-behavior: none;
  background: #0b0b12;
  color: #e8e8f0;
  font-family: system-ui, -apple-system, 'Segoe UI', sans-serif;
}
body { position: fixed; inset: 0; }
* { box-sizing: border-box; }
#app { position: fixed; inset: 0; width: auto; height: auto; overflow: clip; }

/* 数值由滑块、键盘或直接输入调整，统一隐藏浏览器自带的上下微调箭头。 */
input[type='number'] { appearance: textfield; -moz-appearance: textfield; }
input[type='number']::-webkit-inner-spin-button,
input[type='number']::-webkit-outer-spin-button { margin: 0; -webkit-appearance: none; appearance: none; }