apoca1ipsis

<div class="parent">
    <div class="slider"></div>
    <div class="content"></div>
</div>

.parent {
  position: relative;
}
.slider {
  position: absolute;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  z-index: 1;
}
.content {
  position: relative;
  z-index: 2;
}

h2:after {
    content: "";
    display: block;
    height: 200vh;
    width: 1px;
    position: absolute;
    left: 57px;
    top: 0;
    background: #f00;
}

.mcb-wrap {
overflow: hidden;
}

.container {
 display: flex;
 justify-content: space-between;
 position: relative;
padding-bottom: 48px (задать высоту .b2)
}

.b2 {
position: absolute; 
right: 0;
bottom: 0
}

<meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, minimum-scale=1">