Need Help for changing Background

I have changed my web sight background but i am not sure this is proper way and all the place also not filled pleas help me
i did this way add this code to add stylish

.section-overlay-layer {
background-color: #001f3f;
}
.fa-search
{
background-color: #FFFFFF;
}
.site-header-menu
{
background-color: #001f3f;
}
.single-service
{
background-color: #001f3f;
}
.shop
{
background-color: #001f3f;
}
.pic-container
{
background: #001f3f;
}
.feedback-text-wrap
{
background: #001f3f;
}
.footer
{
background: #001f3f;
}
.content-wrap
{
background: #001f3f;
}

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