.header {
    background-color: #212121;
    color: #fff;
    padding-top: 2rem;
    padding-bottom: 2rem;
    text-align: center;
}

.subtitle {
    margin-top: 1rem;
    margin-bottom: 2rem;
}

.container {
    max-width: 800px;
}

.value-prop {
    text-align: center;
}
.value-prop-header {
    text-transform: uppercase;
    font-size: 1.7rem;
    letter-spacing: .1rem;
    font-weight: 600;
}

.section {
    border-top: 1px solid #eee;
    padding: 4rem 0;
    margin-bottom: 0;
}
.section-header {
    text-transform: uppercase;
    font-size: 1.4rem;
    letter-spacing: .2rem;
    font-weight: 600;
}

.screenshot {
    width: 100%;
    height: auto;
}

.footer {
    border-top: 1px solid #eee;
    padding-top: 4rem;
    padding-bottom: 2rem;
    padding-left: 0;
    padding-right: 0;
    margin-bottom: 0;
    font-size: 0.7em;
    text-align: center;
}
body {
    background-color: #eee;
}

.header {
    background-color: #212121;
    color: #fff;
    padding-top: 2rem;
    padding-bottom: 2rem;
    text-align: center;
}

.subtitle {
    margin-top: 1rem;
    margin-bottom: 2rem;
}

.container {
    max-width: 900px;
    background-color: #fff;
    padding-left: 4rem;
    padding-right: 4rem;
}

.value-prop {
    text-align: center;
}
.value-prop-header {
    text-transform: uppercase;
    font-size: 1.7rem;
    letter-spacing: .1rem;
    font-weight: 600;
}

.section {
    border-top: 1px solid #eee;
    padding: 4rem 0;
    margin-bottom: 0;
}
.section-header {
    text-transform: uppercase;
    font-size: 1.4rem;
    letter-spacing: .2rem;
    font-weight: 600;
}

.screenshot {
    width: 100%;
    height: auto;
}

.footer {
    border-top: 1px solid #eee;
    padding-top: 4rem;
    padding-bottom: 2rem;
    padding-left: 0;
    padding-right: 0;
    margin-bottom: 0;
    font-size: 0.7em;
    text-align: center;
}
Tweak background color and middle column padding
Tweak background color and middle column padding
