// 警告框
._alert(@bg_color, @bd_color, @text_color) {
    padding: 15px;
    border: 1px solid @bd_color;
    border-radius: 4px;
    color: @text_color;
    background-color: @bg_color;

    a {
        font-weight: bold;
        color: darken(@text_color, 10%);
    }
}
.alert-green() {
    ._alert(@alert_green_background; @alert_green_border; @alert_green_text);
}
.alert-blue() {
    ._alert(@alert_blue_background; @alert_blue_border; @alert_blue_text);
}
.alert-yellow() {
    ._alert(@alert_yellow_background; @alert_yellow_border; @alert_yellow_text);
}
.alert-red() {
    ._alert(@alert_red_background; @alert_red_border; @alert_red_text);
}