cheese-theme/scss/theme/_notices.scss

.notices {
    color: #fff !important;
    background-color: $header-color !important;
    border: 1px solid rgba(0, 0, 0, 0.125) !important;
    border-radius: 0.25rem !important;
}

.notices.yellow {
    border-color: #f39c12 !important;
}

.notices.green {
    border-color: #00bc8c !important;
}

.notices.red {
    border-color: #e74c3c !important;
}

.notices.blue {
    border-color: #3498db !important;
}