我试图将输入字段的宽度设置为80％,但是每当我将其更改为％时,它就无法正常工作.

我的html：

<div class="todo">
  <div class="content">
    <div class="b2">
        Ends:<input class="finishDate" [(ngModel)]="toDo$.finishDate">
        <mat-divider></mat-divider>
    </div>
  </div>
</div>

我的待办事项组件的完整CSS.

   @media  screen and (min-width: 500px) {
  .todo {
    display:flex;
  }
}


.b1 input[type=text]{
  text-decoration: underline#334A5A ;
  text-transform: uppercase;
  font-weight:bold;
  font-size:19px;
  font-family: 'Old Standard TT',serif;
  color:#0C1824;
}
input {
  border:none;
  outline: none;
  width:100%;
  Box-sizing:border-Box;
}
.delete {
  text-align:center;
}

input {
  outline: none;
  border: 1px solid red;
}

.b2 {
  display: flex;
}

.finishDate {
  flex-grow: 1;
}

<div class="todo">
  <div class="content">
    <div class="b2">
        <label for="finishDate">Ends:</label>
        <input id="finishDate" class="finishDate">
    </div>
  </div>
</div>