.container{
  height: 100%;
}
.nav {
    height: 85rpx;
    width: 100%;
    box-sizing: border-box;
    overflow: hidden;
    line-height: 70rpx;
    font-size: 16px;
    white-space: nowrap;
    position: fixed;
    top: 0;
    left: 0;
    z-index: 99;
}
.nav-item {
    width: 25%;
    display: inline-block;
    text-align: center;
}
.active{
    color: green;
    border-bottom: 3rpx solid green;
}

.tab-box{
    padding-top: 85rpx;
    height: 100%;
    box-sizing: border-box;
}
.tab-content{
  overflow-y: scroll;
  width: 100%;
}
.tappable{
  color: #1aad19;
  padding: 0 12px;
}

text.start-answer{
  position: fixed;
  right: 8rpx;
}
.exercise{
  background: white;
  padding: 17rpx 14rpx;
  margin: 14rpx 0rpx;
  border-radius: 12rpx;
}
.exercise-info{
  margin-top: 4rpx;
  align-items: center;
}
.exercise-tip{
  color: white;
  font-size: 10px;
  height: 14px;
  background: lightblue;
  border-radius: 14rpx;
  padding: 4rpx 16rpx;
  margin-left: 18rpx;
  text-align: center;
}

view.no-content{
  display: flex;
  flex-direction: column;
}

image.no-content{
  width: 300rpx;
  height: 300rpx;
}