motsu0

.control{
  text-align: center;
}
.control__row{
  margin: 40px auto;
  overflow-x: auto;
}
.input-color{
  width: 100px;
  height: 30px;

motsu0

.sandglass{
  box-sizing: border-box;
  width: 90%;
  max-width: 400px;
  margin: 100px auto;
  position: relative;

  user-select: none;
}
.sandglass::after{

motsu0

.settings-row{
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  row-gap: 8px;
  padding: 12px;
  margin: 12px 0;
  background-color: #eee;
}
.label-input{

motsu0

<button id="bt-start">降らせる</button>
<button id="bt-stop">止める</button>

<script src="pathto/raining-particles.js"></script>

motsu0

#quiz{
  display: flex;
  flex-direction: column;
  box-sizing: border-box;
  height: 90vh;

  border: 2px solid #777;
  background-color: #fff;
  -webkit-tap-highlight-color: transparent;
}

motsu0

.settings-row{
  margin: 12px 0;
}
#sel-width,#sel-height{
  width: 60px;
}
#bt-make{
  cursor: pointer;
}
/*  */

motsu0

.img-sample{
  width: 150px;

  border: 1px solid #777;
}
/*  */
.block{
  box-sizing: border-box;
  padding: 16px;
  margin: 20px 0;

motsu0

#input{
  display: block;
  width: 100%;
  height: 100px;
  resize: vertical;

  font-size: 16px;
}
.settings{
  margin: 8px 0;

motsu0

[
  {
    "question": "次のうち、あ行のひらがなはどれでしょうか？",
    "answers": [
      "か","そ","16","う","亜"
    ],
    "index-answer": 3
  },
  {
    "question": "0から100までの整数を全てかけると答えは？",

motsu0

@charset "utf-8";
:root{
  --main-color: #0288D1;
  --sub-color: #B3E5FC;
  --attention-color: #D32F2F;
  --correct-color: #D32F2F;
  --wrong-color: #303F9F;
}
#quiz{
  width: 100%;