如何让浏览器窗口缩放时按钮保持固定位置？

问题根源 #

你给按钮设置了left:94%+固定宽度100px，当浏览器窗口宽度缩到小于1667px左右时，94%的位置加上按钮宽度会超出视口，导致按钮被挤变形甚至重叠。虽然用了position:absolute，但定位逻辑没利用好绝对定位的特性。

方案一：快速修改定位属性（适配现有代码） #

把left:94%改成right:1%（右侧间距可自行调整），让按钮始终贴着右侧边缘，不会随窗口宽度变化错位。同时去掉重复的position:absolute（通用类里已经定义过）。

修复后的CSS：

html, body {
    width: 100%;
    height: 100%;
    margin: 0px;
    border: 0;
    overflow: hidden; /*  Disable scrollbars */
    display: block;  /* No floating content on sides */
}

.button-a,.button-b {
  padding: 0.6em 2em;
  border: none;
  outline: none;
  color: rgb(255, 255, 255);
  background: rgb(209, 192, 192);
  cursor: pointer;
  position: absolute;
  z-index: 0;
  border-radius: 10px;
  user-select: none;
  -webkit-user-select: none;
  touch-action: manipulation;
}

.button-a:before,.button-b:before {
  content: "";
  background: linear-gradient(
    45deg,
    #ff0000,
    #ff7300,
    #fffb00,
    #48ff00,
    #00ffd5,
    #002bff,
    #7a00ff,
    #ff00c8,
    #ff0000
  );
  position: absolute;
  top: -2px;
  left: -2px;
  background-size: 400%;
  z-index: -1;
  filter: blur(5px);
  -webkit-filter: blur(5px);
  width: calc(100% + 4px);
  height: calc(100% + 4px);
  animation: glowing-button-color 20s linear infinite;
  transition: opacity 0.3s ease-in-out;
  border-radius: 10px;
}

@keyframes glowing-button-color {
  0% {
    background-position: 0 0;
  }
  50% {
    background-position: 400% 0;
  }
  100% {
    background-position: 0 0;
  }
}

.button-a:after,.button-b:after {
  z-index: -1;
  content: "";
  position: absolute;
  width: 100%;
  height: 100%;
  background: #222;
  left: 0;
  top: 0;
  border-radius: 10px;
}

.button-a {
    top:1%;
    right:1%; /* 替换left，设置右侧间距 */
    width:100px;
    height:40px;
    background: none; 
}

.button-b {
    top:5.9%;
    right:1%; /* 替换left，设置右侧间距 */
    width:100px;
    height:40px;
    background: none; 
}

HTML保持不变：

<button type="button" class="button-a" id="button_a">A</button>
<button type="button" class="button-b" id="button_b">B</button>

方案二：用Flex布局（更现代易维护） #

如果不想用绝对定位，给body加Flex布局，把按钮固定在右侧，自动垂直排列，不用手动算top值。

修改后的HTML：

<div class="button-container">
  <button type="button" class="button-a" id="button_a">A</button>
  <button type="button" class="button-b" id="button_b">B</button>
</div>

修改后的CSS：

html, body {
    width: 100%;
    height: 100%;
    margin: 0px;
    border: 0;
    overflow: hidden;
    display: flex;
    justify-content: flex-end; /* 让按钮容器靠右 */
    padding: 1% 1% 0 0; /* 顶部+右侧间距 */
    box-sizing: border-box; /* 避免padding撑大视口 */
    flex-direction: column; /* 按钮垂直排列 */
    gap: 10px; /* 按钮之间的间距，替代手动top值 */
}

.button-a,.button-b {
  padding: 0.6em 2em;
  border: none;
  outline: none;
  color: rgb(255, 255, 255);
  background: rgb(209, 192, 192);
  cursor: pointer;
  z-index: 0;
  border-radius: 10px;
  user-select: none;
  -webkit-user-select: none;
  touch-action: manipulation;
  width:100px;
  height:40px;
  background: none; 
  position: relative; /* 确保伪元素正常工作 */
}

.button-a:before,.button-b:before {
  content: "";
  background: linear-gradient(
    45deg,
    #ff0000,
    #ff7300,
    #fffb00,
    #48ff00,
    #00ffd5,
    #002bff,
    #7a00ff,
    #ff00c8,
    #ff0000
  );
  position: absolute;
  top: -2px;
  left: -2px;
  background-size: 400%;
  z-index: -1;
  filter: blur(5px);
  -webkit-filter: blur(5px);
  width: calc(100% + 4px);
  height: calc(100% + 4px);
  animation: glowing-button-color 20s linear infinite;
  transition: opacity 0.3s ease-in-out;
  border-radius: 10px;
}

@keyframes glowing-button-color {
  0% {
    background-position: 0 0;
  }
  50% {
    background-position: 400% 0;
  }
  100% {
    background-position: 0 0;
  }
}

.button-a:after,.button-b:after {
  z-index: -1;
  content: "";
  position: absolute;
  width: 100%;
  height: 100%;
  background: #222;
  left: 0;
  top: 0;
  border-radius: 10px;
}

内容的提问来源于stack exchange，提问作者Pastel