CSS Off canvas导航删除固定顶部

Question

我只使用工作滚动的画布导航CSS。 该导航用于台式机，平板电脑和移动设备。 问题是我不希望它再被修复到顶部。

当我删除“position：fixed”时，它会给我一些位置问题，双滚动条和导航菜单不再正常工作。

我对此问题有什么遗漏或忽视？

我的片段：

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html,
body {
  height: 100%;
}

body {
  font-family: 'Helvetica Neue', Helvetica, sans-serif;
}

#fix-bar {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 9;
  width: 100%;
  height: 60px;
  background-color: #00a8eb;
}

#fix-bar .logo {
  position: absolute;
  left: 0;
  width: 250px;
  -webkit-transform: translate3d(-50%, 0, 0);
  transform: translate3d(-50%, 0, 0);
  -webkit-transition: -webkit-transform 0.5s ease;
  transition: -webkit-transform 0.5s ease;
  transition: transform 0.5s ease;
  transition: transform 0.5s ease, -webkit-transform 0.5s ease;
}

#fix-bar .logo a {
  display: block;
  color: #fff;
  text-decoration: none;
  text-transform: uppercase;
  line-height: 24px;
  width: 60px;
  height: 24px;
  padding: 18px 16px 18px 24px;
  box-sizing: content-box;
}

#fix-bar .push {
  position: relative;
  left: 0;
  height: 100%;
  background-color: #00a8eb;
  -webkit-transition: -webkit-transform 0.5s ease;
  transition: -webkit-transform 0.5s ease;
  transition: transform 0.5s ease;
  transition: transform 0.5s ease, -webkit-transform 0.5s ease;
}

.hamburguer {
  width: 72px;
  height: 60px;
  display: block;
  position: relative;
  cursor: pointer;
}

.hamburguer span {
  display: block;
  position: absolute;
  height: 4px;
  width: 24px;
  background: #fff;
  opacity: 1;
  left: 24px;
  -webkit-transform: rotate(0deg);
  transform: rotate(0deg);
  -webkit-transition: 0.3s ease-in-out;
  transition: 0.3s ease-in-out;
}

.hamburguer span:nth-child(1) {
  top: 20px;
}

.hamburguer span:nth-child(2),
.hamburguer span:nth-child(3) {
  top: 28px;
}

.hamburguer span:nth-child(4) {
  top: 36px;
}

#canvas {
  position: relative;
  height: 100%;
  padding-top: 60px;
  overflow: hidden;
}

#nav {
  overflow-y: scroll;
  position: absolute;
  left: 0;
  height: 100%;
  width: 250px;
  -webkit-transform: translate3d(-50%, 0, 0);
  transform: translate3d(-50%, 0, 0);
  -webkit-transition: -webkit-transform 0.5s ease;
  transition: -webkit-transform 0.5s ease;
  transition: transform 0.5s ease;
  transition: transform 0.5s ease, -webkit-transform 0.5s ease;
  padding-top: 12px;
  padding-bottom: 60px;
}

#nav a {
  text-decoration: none;
  color: #000;
  display: block;
  padding: 14px 24px;
  font: 20px/1 'Montserrat', sans-serif;
  font-weight: 700;
}

#nav a:hover {
  background-color: #eee;
}

#nav .site-menu {
  position: relative;
  min-height: 100%;
  padding-bottom: 60px;
}

#nav .copy {
  position: absolute;
  bottom: 0;
  padding: 16px 24px;
  font-size: 12px;
  line-height: 1.4;
}

#content {
  background-color: #fff;
  overflow-y: scroll;
  position: relative;
  left: 0;
  height: 100%;
  -webkit-transition: -webkit-transform 0.5s ease;
  transition: -webkit-transform 0.5s ease;
  transition: transform 0.5s ease;
  transition: transform 0.5s ease, -webkit-transform 0.5s ease;
  -webkit-transform: translate3d(0, 0, 0);
  transform: translate3d(0, 0, 0);
  padding: 20px;
}

.mask {
  position: absolute;
  top: 60px;
  left: 0;
  z-index: -1;
  width: 100%;
  height: 100%;
  opacity: 0;
  -webkit-transition: opacity 0.5s ease, z-index 0s 0.5s, -webkit-transform 0.5s ease;
  transition: opacity 0.5s ease, z-index 0s 0.5s, -webkit-transform 0.5s ease;
  transition: opacity 0.5s ease, transform 0.5s ease, z-index 0s 0.5s;
  transition: opacity 0.5s ease, transform 0.5s ease, z-index 0s 0.5s, -webkit-transform 0.5s ease;
  background-color: rgba(0, 0, 0, 0.5);
}

input#show-menu {
  position: absolute;
  opacity: 0;
}

input#show-menu:checked~#fix-bar .push {
  -webkit-transform: translate3d(250px, 0, 0);
  transform: translate3d(250px, 0, 0);
}

input#show-menu:checked~#fix-bar .hamburguer span:nth-child(1),
input#show-menu:checked~#fix-bar .hamburguer span:nth-child(4) {
  top: 28px;
  width: 0;
  left: 50%;
}

input#show-menu:checked~#fix-bar .hamburguer span:nth-child(2) {
  -webkit-transform: rotate(45deg);
  transform: rotate(45deg);
}

input#show-menu:checked~#fix-bar .hamburguer span:nth-child(3) {
  -webkit-transform: rotate(-45deg);
  transform: rotate(-45deg);
}

input#show-menu:checked~#canvas .mask {
  z-index: 1;
  opacity: 1;
  -webkit-transform: translate3d(250px, 0, 0);
  transform: translate3d(250px, 0, 0);
  -webkit-transition: opacity 0.5s ease, -webkit-transform 0.5s ease;
  transition: opacity 0.5s ease, -webkit-transform 0.5s ease;
  transition: opacity 0.5s ease, transform 0.5s ease;
  transition: opacity 0.5s ease, transform 0.5s ease, -webkit-transform 0.5s ease;
}

input#show-menu:checked~#canvas #nav,
input#show-menu:checked~#fix-bar .logo {
  -webkit-transform: translate3d(0, 0, 0);
  transform: translate3d(0, 0, 0);
}

input#show-menu:checked~#canvas #content {
  -webkit-transform: translate3d(250px, 0, 0);
  transform: translate3d(250px, 0, 0);
}

<input type="checkbox" id="show-menu">

<div id="fix-bar">
  <div class="logo">
    <a href="/">Branding</a>
  </div>

  <div class="push">
    <label class="hamburguer" for="show-menu">
        <span></span>
        <span></span>
        <span></span>
        <span></span>
      </label>
  </div>
</div>

<div id="canvas">

  <div id="nav">
    <ul class="site-menu">
      <li><a href="#/work">1</a></li>
      <li><a href="#/work">2</a></li>
      <li><a href="#/work">3</a></li>
      <li><a href="#/work">4</a></li>
      <li><a href="#/work">5</a></li>
      <li><a href="#/work">6</a></li>
      <li><a href="#/work">7</a></li>
      <li><a href="#/work">8</a></li>
      <li><a href="#/work">9</a></li>
      <li><a href="#/work">10</a></li>
      <li><a href="#/work">11</a></li>
      <li><a href="#/work">12</a></li>
      <li><a href="#/work">13</a></li>
      <li><a href="#/work">14</a></li>
      <li><a href="#/work">15</a></li>
      <li><a href="#/work">16</a></li>
      <li><a href="#/work">17</a></li>
      <li><a href="#/work">18</a></li>
      <li><a href="#/work">19</a></li>
      <li><a href="#/work">20</a></li>
    </ul>
  </div>

  <label for="show-menu" class="mask"></label>

  <div id="content">
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  </div>