page.css

body {
    background-color: #3876b6;
    background: -webkit-linear-gradient(left, #376bb0 0%, #1a96cc 50%, #376bb0 100%); /* Chrome10-25,Safari5.1-6 */
    background: linear-gradient(to right, #376bb0 0%, #1a96cc 50%, #376bb0 100%); /* W3C, IE10+, FF16+, Chrome26+, Opera12+, Safari7+ */
    margin: 0;
    padding: 0;
}

header {
    background-color: white;
    margin: 0;
    padding: 15px;
    border-bottom: 5px solid #d5d5d5;
}

.group_id {
    display: inline-block;
    vertical-align: top;
    border-radius: 5px;
    background-color: #e9e9e9;
    margin: 5px;
    padding: 0px;
    padding-bottom: 5px;
    width: 100%;
}

.active_group {
    background-color: white;
}

.group_head {
    margin-left: 0;
    margin-right: 0;
    margin-top: 10px;
    margin-bottom: 10px;
    padding-left: 15px;
    padding-right: 15px;
    padding-bottom: 15px;
    border-bottom: 2px solid #d5d5d5;
}

.active_group .group_head .group_set_active {
    display: none;
}

#groups_list {
    -webkit-column-count: 3;
    column-count: 2;
    -webkit-column-gap: 20px;
    column-gap: 0px;
    column-fill: balance;
    padding: 20px;
}

.tabs_list {
    max-height: 400px;
    overflow: auto;
    list-style-type: none;
    padding: 7px;
}

.tabs_list li {
    clear: right;
    padding-left: 15px;
    min-height: 25px;
    line-height: 25px;
    margin-bottom: 1px;
    cursor: pointer;
}

.tabs_list li img {
    vertical-align: middle;
}

.tabs_list li:hover {
    background-color: #929292;
}

.tabButtons {
    float: right;
}

.tabCloseButton {
    padding: 1px 2px;
    margin: 2px;
}

.group_move {
    display: none;
}

.group_name {
    margin-right: 10px;
}

.group_new_tab,
.group_remove {
    float: right;
    margin-left: 10px;
}

#help {
    float: right;
    position: relative;
}

#help_hidden {
    display: none;
    position: absolute;
    top: 20px;
    right: 0px;
    width: 400px;
    border: 2px solid;
    border-radius: 5px;
    border-color: #929292;
    background-color: white;
    padding: 6px;
}

#help:hover #help_hidden {
    display: block;
}