Generated by SassMeister.com.

SassMeister-input-HTML.haml

%header.site-header
  .wrap 
     
    .logo
      %a{ href: "#"} Logo
    %nav
      %ul
        %li
          %a{ href: "#"} item 01
        %li
          %a{ href: "#"} item 02
        %li
          %a{ href: "#"} item 03
        %li
          %a{ href: "#"} item 04
        %li
          %a{ href: "#"} item 05
          
  .wrap
    %main.content
      %h2 Gallery Content
      %ul.gallery
        %li.gallery__item
          %img{ src: "http://www.placehold.it/300x300", alt: "Placeholder Image"}
        %li.gallery__item
          %img{ src: "http://www.placehold.it/300x300", alt: "Placeholder Image"}
        %li.gallery__item
          %img{ src: "http://www.placehold.it/300x300", alt: "Placeholder Image"}
        %li.gallery__item
          %img{ src: "http://www.placehold.it/300x300", alt: "Placeholder Image"}
        %li.gallery__item
          %img{ src: "http://www.placehold.it/300x300", alt: "Placeholder Image"}
        %li.gallery__item
          %img{ src: "http://www.placehold.it/300x300", alt: "Placeholder Image"}
        %li.gallery__item
          %img{ src: "http://www.placehold.it/300x300", alt: "Placeholder Image"}
        %li.gallery__item
          %img{ src: "http://www.placehold.it/300x300", alt: "Placeholder Image"}
        %li.gallery__item
          %img{ src: "http://www.placehold.it/300x300", alt: "Placeholder Image"}
        %li.gallery__item
          %img{ src: "http://www.placehold.it/300x300", alt: "Placeholder Image"}
        %li.gallery__item
          %img{ src: "http://www.placehold.it/300x300", alt: "Placeholder Image"}
        %li.gallery__item
          %img{ src: "http://www.placehold.it/300x300", alt: "Placeholder Image"}
        %li.gallery__item
          %img{ src: "http://www.placehold.it/300x300", alt: "Placeholder Image"}
        %li.gallery__item
          %img{ src: "http://www.placehold.it/300x300", alt: "Placeholder Image"}
        %li.gallery__item
          %img{ src: "http://www.placehold.it/300x300", alt: "Placeholder Image"}
          
    .sidebar
      %h2 Sidebar
      %ul
        %li
          %a{ href: "#"} A link to someplace else

SassMeister-input.sass

// ----
// Sass (v3.4.12)
// Compass (v1.0.3)
// Susy (v2.2.2)
// ----

// Odd bug from Page 105
//@import compass-mixins
//@import susy
//@import "compass-mixins"
@import susy

@mixin cf
  &:after
    content: ""
    display: block
    clear: both
    
$susy: (columns: 16, container: 1140px, global-box-sizing: border-box, debug: (image: show))

+border-box-sizing

.wrap
  +container(1140px show)

h2
  padding: 1rem 0
  text-align: center
  color: #555555

ul, ol
  margin: 0
  padding: 0

li
  list-style: none

img
  max-width: 100%
  height: auto

.site-header, .site-footer
  background: rgba(234, 159, 195, 0.8)

.site-header
  a
    color: #555555
    text-decoration: none

.content
  margin-top: 5vh
  padding-bottom: 1rem
  background: rgba(113, 218, 210, 0.8)
  +span(12 of 16)

.sidebar
  margin-top: 5vh
  background: rgba(250, 231, 179, 0.8)
  padding-bottom: 1rem
  +span(4 of 16 last) 
  
  a
    color: #666666
    padding-left: 1rem
    line-height: 2
    text-decoration: none
  .widget
    background: rgba(240, 150, 113, 0.8)
  
  .site-footer
    margin-top: 5vh
    
.logo
  float: left
  line-height: 2rem
  font-size: 1.5rem
  
nav
  float: right
  
  li
    list-style: none
    float: left
    margin-left: 1em
    line-height: 2rem

.gallery
  +cf
  background: rgb(200, 200, 2)
  +span(10 of 12)
  // The margin trick isn't working as described in book; report later
  margin-left: auto 
  margin-right: auto
  
  

SassMeister-output.css

*, *:before, *:after {
  -moz-box-sizing: border-box;
  -webkit-box-sizing: border-box;
  box-sizing: border-box;
}

.wrap {
  max-width: 1140px;
  margin-left: auto;
  margin-right: auto;
  background-image: linear-gradient(to right, rgba(102, 102, 255, 0.25), rgba(179, 179, 255, 0.25) 80%, transparent 80%);
  background-size: 6.32911%;
  background-origin: content-box;
  background-clip: content-box;
  background-position: left top;
}
.wrap:after {
  content: " ";
  display: block;
  clear: both;
}

h2 {
  padding: 1rem 0;
  text-align: center;
  color: #555555;
}

ul, ol {
  margin: 0;
  padding: 0;
}

li {
  list-style: none;
}

img {
  max-width: 100%;
  height: auto;
}

.site-header, .site-footer {
  background: rgba(234, 159, 195, 0.8);
}

.site-header a {
  color: #555555;
  text-decoration: none;
}

.content {
  margin-top: 5vh;
  padding-bottom: 1rem;
  background: rgba(113, 218, 210, 0.8);
  width: 74.68354%;
  float: left;
  margin-right: 1.26582%;
}

.sidebar {
  margin-top: 5vh;
  background: rgba(250, 231, 179, 0.8);
  padding-bottom: 1rem;
  width: 24.05063%;
  float: right;
  margin-right: 0;
}
.sidebar a {
  color: #666666;
  padding-left: 1rem;
  line-height: 2;
  text-decoration: none;
}
.sidebar .widget {
  background: rgba(240, 150, 113, 0.8);
}
.sidebar .site-footer {
  margin-top: 5vh;
}

.logo {
  float: left;
  line-height: 2rem;
  font-size: 1.5rem;
}

nav {
  float: right;
}
nav li {
  list-style: none;
  float: left;
  margin-left: 1em;
  line-height: 2rem;
}

.gallery {
  background: #c8c802;
  width: 83.05085%;
  float: left;
  margin-right: 1.69492%;
  margin-left: auto;
  margin-right: auto;
}
.gallery:after {
  content: "";
  display: block;
  clear: both;
}

SassMeister-rendered.html

<header class='site-header'>
  <div class='wrap'>
    &nbsp;
    <div class='logo'>
      <a href='#'>Logo</a>
    </div>
    <nav>
      <ul>
        <li>
          <a href='#'>item 01</a>
        </li>
        <li>
          <a href='#'>item 02</a>
        </li>
        <li>
          <a href='#'>item 03</a>
        </li>
        <li>
          <a href='#'>item 04</a>
        </li>
        <li>
          <a href='#'>item 05</a>
        </li>
      </ul>
    </nav>
  </div>
  <div class='wrap'>
    <main class='content'>
      <h2>Gallery Content</h2>
      <ul class='gallery'>
        <li class='gallery__item'>
          <img alt='Placeholder Image' src='http://www.placehold.it/300x300'>
        </li>
        <li class='gallery__item'>
          <img alt='Placeholder Image' src='http://www.placehold.it/300x300'>
        </li>
        <li class='gallery__item'>
          <img alt='Placeholder Image' src='http://www.placehold.it/300x300'>
        </li>
        <li class='gallery__item'>
          <img alt='Placeholder Image' src='http://www.placehold.it/300x300'>
        </li>
        <li class='gallery__item'>
          <img alt='Placeholder Image' src='http://www.placehold.it/300x300'>
        </li>
        <li class='gallery__item'>
          <img alt='Placeholder Image' src='http://www.placehold.it/300x300'>
        </li>
        <li class='gallery__item'>
          <img alt='Placeholder Image' src='http://www.placehold.it/300x300'>
        </li>
        <li class='gallery__item'>
          <img alt='Placeholder Image' src='http://www.placehold.it/300x300'>
        </li>
        <li class='gallery__item'>
          <img alt='Placeholder Image' src='http://www.placehold.it/300x300'>
        </li>
        <li class='gallery__item'>
          <img alt='Placeholder Image' src='http://www.placehold.it/300x300'>
        </li>
        <li class='gallery__item'>
          <img alt='Placeholder Image' src='http://www.placehold.it/300x300'>
        </li>
        <li class='gallery__item'>
          <img alt='Placeholder Image' src='http://www.placehold.it/300x300'>
        </li>
        <li class='gallery__item'>
          <img alt='Placeholder Image' src='http://www.placehold.it/300x300'>
        </li>
        <li class='gallery__item'>
          <img alt='Placeholder Image' src='http://www.placehold.it/300x300'>
        </li>
        <li class='gallery__item'>
          <img alt='Placeholder Image' src='http://www.placehold.it/300x300'>
        </li>
      </ul>
    </main>
    <div class='sidebar'>
      <h2>Sidebar</h2>
      <ul>
        <li>
          <a href='#'>A link to someplace else</a>
        </li>
      </ul>
    </div>
  </div>
</header>