Reusable, Responsive Grids 1/2, 3/3, 2/3 & 1/3 All CSS

index.html

<div class="container">
<header>header</header>
<div class="grid-wrapper">
  <article class="half-left">
    Left half
  </article>
  <article class="half-right">
    Right half
  </article>
 </div> 
<div class="content">Content</div>
<div class="grid-wrapper-equal-thirds">
  <article class="left-third">
    Left third
  </article>
  <article class="middle-third">
    middle third
  </article>
  <article class="right-third">
    Right third
  </article>
 </div>
<div class="content">Content</div>
<div class="grid-wrapper">
  <article class="half-left">
    Left half
  </article>
  <article class="half-right">
    Right half
  </article>
 </div>
 <div class="content">Content</div>
<div class="grid-wrapper-two-thirds">
<article class="left-two-thirds">
    Left two thirds
  </article>
  <article class="right-one-third">
    Right one third
  </article>
</div>

<footer>Footer</footer>
  </div>

reusable-responsive-grids-1-2-3-3-2-3-1-3-all-css.markdown

Reusable, Responsive Grids 1/2, 3/3, 2/3 & 1/3 All CSS

A Pen by Sumon Islam on CodePen.

License.

style.css

body {
  text-align: center;
  margin: 20px;
  color: #fff;
  text-transform: uppercase;
  font-family: sans-serif;
  font-weight: 700;
  height: 100vh;
}
.container {
  max-width: 1240px;
  margin: 0 auto;
}
article {
  padding: 1em;
  margin-bottom: 20px;
}
header,
footer {
  background-color: #6A5ACD;
  padding: 1em;
  margin-bottom: 20px;
  height: 60px;
}
.content {
  width: calc(1000vw -40);
  height: 180px;
  background-color:red;
  padding: 1em;
  margin-bottom: 20px;
}
header {
  grid-area: header;
}
footer {
  grid-area: footer;
}
.grid-wrapper {
  display: grid;
  grid-template-columns: calc(50vw -40) calc(50vw-40) ;
  grid-template-rows: 1;
  grid-gap: 20px;
  grid-template-areas: "left-half right-half";
}
.half-left {
  grid-area: left-half;
  background-color: #9ACD32;
}
.half-right {
  grid-area: right-half;
  background-color: #9ACD32;
}
.grid-wrapper-equal-thirds {
  display: grid;
  grid-template-columns: calc(33vw -50) calc(33vw-50) calc(33vw-50) ;
  grid-template-rows: 1;
  grid-gap: 20px;
  grid-template-areas: "left-third middle-third right-third";
}
.left-third, .middle-third, .right-third {
  background-color: #1E90FF;
  padding: 1em;
  margin-bottom: 20px;
}
.grid-wrapper-two-thirds {
  display: grid;
  grid-template-columns: 
    66% calc(33% - 10px);
  grid-template-rows: 1;
  grid-gap: 20px;
  grid-template-areas: "left-two-thirds right-one-third";
}
.left-two-thirds, .right-one-third {
  background-color: #FF6347;
  padding: 1em;
  margin-bottom: 20px;
}

@media screen and (max-width: 700px) {
	.grid-wrapper {
		grid-template-areas: "left-half" "right-half";
		grid-template-columns: 100%;
		grid-template-rows: 100px 
							100px;
      grid-row-gap: 0;
	}
  .left-half, .right-half {
    margin: 0px;
  }
	.grid-wrapper-equal-thirds {
		grid-template-areas: "left-third" "middle-third" "right-third";
		grid-template-columns: 100%;
		grid-template-rows: 100px 100px 100px;
      grid-gap: 20;
	}
  .left-third, .middle-third {
    margin: 0px;
  }
.grid-wrapper-two-thirds {
		grid-template-areas: "left-two-thirds" "right-one-third";
		grid-template-columns: 100%;
		grid-template-rows: 100px 100px;
      grid-gap: 20;
	}
  .left-two-thirds {
    margin: 0;
  }
  .right-one-third {
    margin-bottom: 20px;
  }
}