滚动条出现时如何自动增加元素的宽度？

问题描述

当用户减小浏览器的宽度时，我正在制作一个迷你边栏。使用height css属性时，我陷入了困境。我允许用户滚动边栏。

但是当垂直滚动条出现时，我不知道如何自动增加边栏的宽度。

/* START - bootstrap */
.list-unstyled {
  padding-left: 0;
  list-style: none;
}

.m-auto {
  margin: auto;
}

.text-light {
  color: rgb(248,249,250);
}

.text-center {
  text-align: center;
}

.p-3 {
  padding: 1rem!important;
}
/* END - bootstrap */

.sidebar-medium {
  overflow-x: hidden;
  overflow-y: auto;
  display: block;
  top: 0;
  bottom: 0;
  width: 60px;
  position: fixed;
  background-image: linear-gradient(to right,#ff758c 0%,#ff7eb3 100%);
}

li {
  cursor: pointer;
  user-select: none;
  font-size: 20px;
}

li:hover {
  background: rgba(255,255,0.4);
}

.avatar {
    width: 30px;
    height: 30px;
    background-size: 30px 30px;
    clip-path: polygon(50% 0%,90% 20%,100% 60%,75% 100%,25% 100%,0% 60%,10% 20%);
}

<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.14.0/css/all.min.css" />

<div class="shadow-sm text-light sidebar-medium">
    <ul class="list-unstyled mb-0">
        <li class="text-center p-3">
            <div class="align-self-center d-inline-block m-auto avatar" style="background-image: url('https://i.stack.imgur.com/5Jv5C.jpg?s=328&g=1');"></div>
        </li>
        <li class="text-center p-3">
            <div class="align-self-center d-inline-block m-auto text-center">
                <i class="fas fa-user-tie"></i>
            </div>
        </li>
        <li class="text-center p-3">
            <div class="align-self-center d-inline-block m-auto text-center">
                <i class="fas fa-radiation"></i>
            </div>
        </li>
        <li class="text-center p-3">
            <div class="align-self-center d-inline-block m-auto text-center">
                <i class="fas fa-history"></i>
            </div>
        </li>
        <li class="text-center p-3">
            <div class="align-self-center d-inline-block m-auto text-center">
                <i class="fas fa-envelope"></i>
            </div>
        </li>
        <li class="text-center p-3">
            <div class="align-self-center d-inline-block m-auto text-center">
                <i class="fas fa-bell"></i>
            </div>
        </li>
        <li class="text-center p-3">
            <div class="align-self-center d-inline-block m-auto text-center">
                <i class="fas fa-bookmark"></i>
            </div>
        </li>
        <li class="text-center p-3">
            <div class="align-self-center d-inline-block m-auto text-center">
                <i class="fas fa-exclamation-triangle"></i>
            </div>
        </li>
        <li class="text-center p-3">
            <div class="align-self-center d-inline-block m-auto text-center">
                <i class="fas fa-exclamation-circle"></i>
            </div>
        </li>
        <li class="text-center p-3">
            <div class="align-self-center d-inline-block m-auto text-center">
                <i class="fas fa-cogs"></i>
            </div>
        </li>
    </ul>
</div>

屏幕截图（带或不带滚动条）：

在这种情况下（不使用JavaScript）如何自动增加侧边栏的宽度？

解决方法

一种可能的解决方案是查询height。

@media (max-height: 570px) { /* this is when the scrollbar appears */
    .sidebar-medium {
        width: 100px;
    }
}

.list-unstyled {
  padding-left: 0;
  list-style: none;
}

.m-auto {
  margin: auto;
}

.text-light {
  color: rgb(248,249,250);
}

.text-center {
  text-align: center;
}

.p-3 {
  padding: 1rem !important;
}


/* END - bootstrap */

.sidebar-medium {
  overflow-x: hidden;
  overflow-y: auto;
  display: block;
  top: 0;
  bottom: 0;
  width: 60px;
  position: fixed;
  background-image: linear-gradient(to right,#ff758c 0%,#ff7eb3 100%);
  transition: width 0.3s;
}

li {
  cursor: pointer;
  user-select: none;
  font-size: 20px;
}

li:hover {
  background: rgba(255,255,0.4);
}

.avatar {
  width: 30px;
  height: 30px;
  background-size: 30px 30px;
  clip-path: polygon( 50% 0%,90% 20%,100% 60%,75% 100%,25% 100%,0% 60%,10% 20%);
}

@media (max-height: 570px) {
  .sidebar-medium {
    width: 100px;
  }
}

<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.14.0/css/all.min.css" />

<div class="shadow-sm text-light sidebar-medium">
  <ul class="list-unstyled mb-0">
    <li class="text-center p-3">
      <div class="align-self-center d-inline-block m-auto avatar" style="
              background-image: url('https://i.stack.imgur.com/5Jv5C.jpg?s=328&g=1');
            "></div>
    </li>
    <li class="text-center p-3">
      <div class="align-self-center d-inline-block m-auto text-center">
        <i class="fas fa-user-tie"></i>
      </div>
    </li>
    <li class="text-center p-3">
      <div class="align-self-center d-inline-block m-auto text-center">
        <i class="fas fa-radiation"></i>
      </div>
    </li>
    <li class="text-center p-3">
      <div class="align-self-center d-inline-block m-auto text-center">
        <i class="fas fa-history"></i>
      </div>
    </li>
    <li class="text-center p-3">
      <div class="align-self-center d-inline-block m-auto text-center">
        <i class="fas fa-envelope"></i>
      </div>
    </li>
    <li class="text-center p-3">
      <div class="align-self-center d-inline-block m-auto text-center">
        <i class="fas fa-bell"></i>
      </div>
    </li>
    <li class="text-center p-3">
      <div class="align-self-center d-inline-block m-auto text-center">
        <i class="fas fa-bookmark"></i>
      </div>
    </li>
    <li class="text-center p-3">
      <div class="align-self-center d-inline-block m-auto text-center">
        <i class="fas fa-exclamation-triangle"></i>
      </div>
    </li>
    <li class="text-center p-3">
      <div class="align-self-center d-inline-block m-auto text-center">
        <i class="fas fa-exclamation-circle"></i>
      </div>
    </li>
    <li class="text-center p-3">
      <div class="align-self-center d-inline-block m-auto text-center">
        <i class="fas fa-cogs"></i>
      </div>
    </li>
  </ul>
</div>

,

您总是可以使用::-webkit-scrollbar来获得更好的视觉效果：

/* START - bootstrap */

.list-unstyled {
  padding-left: 0;
  list-style: none;
}

.m-auto {
  margin: auto;
}

.text-light {
  color: rgb(248,#ff7eb3 100%);
}

li {
  cursor: pointer;
  user-select: none;
  font-size: 20px;
}

li:hover {
  background: rgba(255,0.4);
}

.avatar {
  width: 30px;
  height: 30px;
  background-size: 30px 30px;
  clip-path: polygon(50% 0%,10% 20%);
}

::-webkit-scrollbar {
  width: 2px;
}

::-webkit-scrollbar-thumb {
  background-color: gray;
  border-radius: 5px;
}

<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.14.0/css/all.min.css" />

<div class="shadow-sm text-light sidebar-medium">
  <ul class="list-unstyled mb-0">
    <li class="text-center p-3">
      <div class="align-self-center d-inline-block m-auto avatar" style="background-image: url('https://i.stack.imgur.com/5Jv5C.jpg?s=328&g=1');"></div>
    </li>
    <li class="text-center p-3">
      <div class="align-self-center d-inline-block m-auto text-center">
        <i class="fas fa-user-tie"></i>
      </div>
    </li>
    <li class="text-center p-3">
      <div class="align-self-center d-inline-block m-auto text-center">
        <i class="fas fa-radiation"></i>
      </div>
    </li>
    <li class="text-center p-3">
      <div class="align-self-center d-inline-block m-auto text-center">
        <i class="fas fa-history"></i>
      </div>
    </li>
    <li class="text-center p-3">
      <div class="align-self-center d-inline-block m-auto text-center">
        <i class="fas fa-envelope"></i>
      </div>
    </li>
    <li class="text-center p-3">
      <div class="align-self-center d-inline-block m-auto text-center">
        <i class="fas fa-bell"></i>
      </div>
    </li>
    <li class="text-center p-3">
      <div class="align-self-center d-inline-block m-auto text-center">
        <i class="fas fa-bookmark"></i>
      </div>
    </li>
    <li class="text-center p-3">
      <div class="align-self-center d-inline-block m-auto text-center">
        <i class="fas fa-exclamation-triangle"></i>
      </div>
    </li>
    <li class="text-center p-3">
      <div class="align-self-center d-inline-block m-auto text-center">
        <i class="fas fa-exclamation-circle"></i>
      </div>
    </li>
    <li class="text-center p-3">
      <div class="align-self-center d-inline-block m-auto text-center">
        <i class="fas fa-cogs"></i>
      </div>
    </li>
  </ul>
</div>