.alert-icon-center-vertically(@font-size) {
    @half-height: @font-size / 2;
    // IE8 doesn't support calc(): it's OK, the icon will just be aligned to the top
    top: calc(~'50% - @{half-height}');
    // phantomjs only supports -webkit-calc()
    top: -webkit-calc(~'50% - @{half-height}');
}

.alert {
    padding: 20px 20px 20px 60px;
    margin-bottom: 20px;
    border: 1px solid transparent;
    border-radius: 2px;
    font-size: 14px;
    position: relative;
    &:before {
        font-family: "piwik";
        content: "\e625";
        position: absolute;
        left: 20px;
        line-height: 100%; // line-height = font-size
        font-size: 24px;
    }

    a {
        color: inherit;
        text-decoration: underline;
    }
}
.alert-success {
    color: #009874;
    border-color: #1AA282;
    &:before {
        content: "\e63d";
        color: #1AA282;
    }
}
.alert-info {
    color: #838383;
    background-color: #F5F5F5;
    font-size: 13px;
    padding-top: 15px;
    padding-bottom: 15px;
    &:before {
        color: #afafaf;
        font-size: 20px;
    }
}
.alert-warning {
    color: #CA8100;
    border-color: #DF9D27;
    &:before {
        content: "\e621";
        color: #DF9D27;
    }
}
.alert-danger {
    color: #D4291F;
    border-color: #D73F36;
    &:before {
        content: "\e616";
        color: #D73F36;
    }
}