CSS在一行中拉伸所有div

body {
  margin:0;
}
.container {
  display:flex;
  flex-wrap:wrap;     
  height:100vh;
  background-color: white;
}
.container > div {
  min-height: 100vh;
  border: 1px solid black;
  box-sizing:border-box;
  background-color: inherit;
}
.container > div > a > .dot{
  position: relative;
  transition: background .2s linear;
  left: 50%;
  bottom: 10%;
  z-index: 101;
    height: 25px;
  width: 25px;
  background-color: white;
  border-radius: 50%;
  display: inline-block;
}
.container > div > a  > .dot > .arrow-down {
  transition: border .2s linear;
  position: absolute;
  top:11%;
  left: 24%;
  border: solid black;
  border-width: 0 3px 3px 0;
  display: inline-block;
  padding: 5px;
}
.container > div > a .dot:hover{
  background: black;
}
.container > div > a .dot:hover > .arrow-down{
    border: solid white;
    border-width: 0 3px 3px 0;
    display: inline-block;
    padding: 5px;
}
.container > div > a > .dot > .arrow-down{
    transform: rotate(45deg);
    -webkit-transform: rotate(45deg);
}

.container > div .content{
  height: 100vh;
  width: 100vw;
  background-color: inherit;
}
.full-width {
  width:100%;   
  position:relative;           
}
.half-width {
  width:50%;
  position:relative;
  overflow: auto
}

.video-iframe.fullsize{
  height: 100%;
  width: 100%;
}

.list{
  text-align: center;
}

.half-width > .half-width-content{
  position: relative;
  margin-top: 0;
  height: 100%;
  width: 100%;
}
.half-width > .half-width-content > .instagram-slideshow{
  position: relative;
  height: 100%;
  width: 100%;
}
.half-width > .half-width-content > .instagram-slideshow > img{
  position: absolute;
  width: 60%;
  height: 60%;
  margin: auto;
  left: 0;
  right: 0;
  top: 0;
  bottom: 0;
  /*left: 50%;
  top:50%;*/
  visibility: visible;
  text-align: center;
  /*-webkit-transform: translate(-50%, -50%);
  transform: translate(-50%, -50%);*/
}

.half-width > .half-width-content > .half-width-text {
  /*position: absolute;
  left: 50%;
  top: 50%;*/
  visibility: visible;
  /*-webkit-transform: translate(-50%, -50%);
  transform: translate(-50%, -50%);*/
  padding-left: 50px;
    padding-right: 50px;
}
.half-width#section2 > .half-width-content, .half-width#section3 > .half-width-content {
    display: flex;
  flex-direction: column;
  justify-content: center;
}

 .half-width > .half-width-content > h1{
  position: relative;
  text-align: center;
  /*top: 15%;*/
}

.half-width-text > .middle-text{
  margin-left: -30px;
}

.list-div {
  height: 100%;
  display: flex;
  justify-content: center;
  align-items: center;
}

.list-div ul {
  padding: 0;
  width: 75%;

}

.list-div li {
  position: relative;
  display: block;
  margin-bottom: 5px;
  padding: 10px;
  text-align: center;
  visibility: visible;
  text-transform: uppercase;
}


.full-width > .content > .third-parent{
  height: 100%;
  display: flex;
}

.full-width > .content > .third-parent > .third{
  position: relative;
  flex: 1 1 0px;

  width: 100%;
      display: flex;
    align-items: center;
    align-content: center;
    justify-content: center;
}

.full-width > .content > .third-parent > .third > img{
  position: absolute;
  width: 100%;
  height: auto;
  left: 50%;
  top:50%;
  visibility: visible;
  text-align: center;
  -webkit-transform: translate(-50%, -50%);
  transform: translate(-50%, -50%);
}

.middle-text{
  /*position: absolute;
  width: 100%;
  left: 50%;
  top:50%;*/
  visibility: visible;
  text-align: center;
  /*-webkit-transform: translate(-50%, -50%);
  transform: translate(-50%, -50%);*/
}

.full-width > .content > .third-parent > .third > .middle-text > .list-div2{
    display: flex;
  justify-content: center;
  align-items: center;
  width: 100%;
}

.full-width > .content > .third-parent > .third > .middle-text > .list-div2  li{
   position: relative;
  display: block;
  border: 1px solid red;
  margin-bottom: 5px;
  padding: 10px;
  text-align: center;
  text-transform: uppercase;
  visibility: visible;
}

.list-div2 li::before{
  content: '\2022';
  margin-right: 10px;
}
.items-list2 {
  margin: 0;
  padding: 0;
}

<div class="container">
  <div class="full-width">
<iframe class="video-iframe fullsize" src="https://www.youtube.com/embed/osg9PmkfTB0" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen></iframe>
    <a href="#section2">
      <span class="dot">
        <i class="arrow-down"></i>
      </span>
    </a>
  </div>
  <div class="half-width" id="section2">
    <div class="half-width-content">
              <h1>Headline</h1>
      <div class="half-width-text">
        <div class="text-content">
        <p>Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet. Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet.</p>
        </div>
      </div>
    </div>
  </div>
  <div class="half-width">
    <div class="half-width-content">
      <div class="instagram-slideshow" id="1">
        <img class="slide" src="http://placekitten.com/200/300">
        <img class="slide" src="https://placeimg.com/640/480/animals">
        <img class="slide" src="http://placekitten.com/200/300">
      </div>
    </div>
  </div>
  <div class="half-width">
    <div class="half-width-content">
      <div class="instagram-slideshow" id="2">
        <img class="slide" src="https://fakeimg.pl/350x200/?text=Hello">
        <img class="slide" src="https://fakeimg.pl/350x200/?text=Bye">
        <img class="slide" src="https://fakeimg.pl/350x200/?text=BLA">
      </div>
    </div>
  </div>
  <div class="half-width" id="section3">
    <div class="half-width-content">
	<div class="middle-text">
	<h2>Headline</h2>
	<p>
	This is some text paragraph
	</p>
      <div class="list-div">
        <ul class="items-list" id="list">
          <li>Lorem ipsum dolor sit amet, consetetur sadipscing elitr</li>
          <li>sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam </li>
          <li>sanctus est Lorem ipsum dolor sit amet. Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua</li>
          <li>At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet.</li>
        </ul>
      </div>
    </div>
	</div>
  </div>
  <div class="full-width" id="section4">
    <div class="content">
       <div class="third-parent">
         <div class="third" id="one">
           <img src="https://fakeimg.pl/350x200/?text=right">
          </div>
        <div class="third" id="two">
          <div class="middle-text">
            <h1>Headline</h1>
                  <div class="list-div2">
        <ul class="items-list2" id="list">
          <li>Entry A</li>
          <li>Entry B</li>
          <li>Entry C</li>
          <li>Entry D</li>
        </ul>
      </div>
          </div>
        </div>
        <div class="third" id="three">
          <img src="https://fakeimg.pl/350x200/?text=left">
        </div>
         </div>
       </div>
</div>
</div>