Цвет фона

.bg-primary
.bg-secondary
.bg-success
.bg-danger
.bg-warning
.bg-info
.bg-light
.bg-dark
.bg-white
Ссылка внутри класса .bg-primary
Ссылка внутри класса .bg-white

Каскадные таблицы стилей CSS советы & приёмы

We love the Big Apple!
We love the Big Apple!
We love the Big Apple!
We love the Big Apple!
We love the Big Apple!

We love the Big Apple!
We love the Big Apple!
We love the Big Apple!
We love the Big Apple!
We love the Big Apple!

We love the Big Apple!
We love the Big Apple!
We love the Big Apple!
We love the Big Apple!
We love the Big Apple!

container bg-primary
container bg-primary

row bg-secondary
row bg-secondary

col-md-6 bg-success
col-md-6 bg-success

col-md-6 bg-danger
col-md-6 bg-danger

container bg-warning
container bg-warning

row bg-info
row bg-info

container bg-light
container bg-light

container bg-dark
container bg-dark

.bg-gradient-primary
.bg-gradient-secondary
.bg-gradient-success
.bg-gradient-danger
.bg-gradient-warning
.bg-gradient-info
.bg-gradient-light
.bg-gradient-dark