:root {
    --tab-font-family: -apple-system, 'Segoe UI', roboto, oxygen-sans, ubuntu, cantarell, 'Helvetica Neue', sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol';
    --tab-font-size: 12px;
    --tab-transition: background-color 200ms ease-out, color 200ms ease-out;
    --tab-cursor: pointer; /* 设置鼠标指针为手型 */
    --tab-color: #7f8792;
    --tab-background: #EFF0F4;
    --tab-active-color: #222529;
    --tab-active-background: #FFFFFF;
    --tab-close-color: #9DA3AC;
}

* {
    margin: 0;
    padding: 0;
}

html, body {
    margin: 0;
    padding: 0;
    font-family: 'Roboto', sans-serif;
    font-size: 16px;
    color: #333;
}

.nav {
    font-family: var(--tab-font-family);
    font-feature-settings: 'clig', 'kern';
    display: flex;
    width: 100%;
    cursor: default;
    background-color: var(--tab-background);
    -webkit-app-region: drag;
}

.nav ul {
    display: flex;
    height: 30px;
    margin: 8px 46px 0 0;
    user-select: none;
    overflow-x: auto;
    overflow-y: hidden;
}

.nav ul::-webkit-scrollbar {
    display: none;
}

.nav ul li {
    display: inline-flex;
    position: relative;
    box-sizing: border-box;
    align-items: center;
    height: 100%;
    padding: 7px 8px;
    margin: 0 8px 0 0;
    min-width: 100px;
    max-width: 240px;
    scroll-margin: 12px;
    font-size: var(--tab-font-size);
    color: var(--tab-color);
    cursor: var(--tab-cursor);
    transition: var(--tab-transition);
    -webkit-app-region: none;
}

.nav ul li:first-child {
    margin-left: 8px;
    border-left: none;
}


.nav ul li.active {
    color: var(--tab-active-color);
    background: var(--tab-active-background);
    border-radius: 6px 6px 0 0;
}

.nav ul li.active::before {
    position: absolute;
    bottom: 0;
    left: -6px;
    width: 6px;
    height: 6px;
    background-image: url(../image/select_left.png);
    background-repeat: no-repeat;
    background-size: cover;
    content: '';
}

.nav ul li.active::after {
    position: absolute;
    right: -6px;
    bottom: 0;
    width: 6px;
    height: 6px;
    background-image: url(../image/select_right.png);
    background-repeat: no-repeat;
    background-size: cover;
    content: '';
}

.nav ul li.active .tab-icon.background {
    background-image: url(../image/link_normal_selected_icon.png);
}


.nav ul li:not(.active)::after {
    position: absolute;
    right: 0;
    width: 1px;
    height: 16px;
    background: rgba(0, 0, 0, 0.08);
    content: '';
}

.nav ul li:not(.active):last-child::after {
    content: none;
}

/* 浏览器打开 */
.browser {
    position: absolute;
    top: 0;
    right: 0;
    display: flex;
    align-items: center;
    height: 38px;
    padding: 0 14px;
    cursor: pointer;
    -webkit-app-region: none;
}
.browser span {
    display: inline-block;
    width: 18px;
    height: 18px;
    background-size: cover;
    background-image: url(../image/link_normal_selected_icon.png);
}

/* 图标 */
.tab-icon {
    display: inline-block;
    flex-shrink: 0;
    width: 18px;
    height: 18px;
    background-size: cover;
}

.tab-icon.background {
    background-image: url(../image/link_normal_icon.png);
}

.tab-icon.loading {
    background-image: none !important;
}

.tab-icon .tab-icon-loading {
    width: 18px;
    height: 18px;
    border: 2px solid #eeeeee;
    border-bottom-color: #84C56A;
    border-radius: 50%;
    display: inline-block;
    box-sizing: border-box;
    animation: spin 0.75s linear infinite;
}

.tab-icon:not(.loading) .tab-icon-loading {
    display: none;
}

.tab-icon img {
    width: 16px;
    height: 16px;
    border-radius: 4px;
}

@keyframes spin {
    0% {
        transform: scale(0.8) rotate(0deg);
    }
    100% {
        transform: scale(0.8) rotate(360deg);
    }
}

/* 标题 */
.tab-title {
    display: inline-block;
    flex: 1;
    margin-right: 8px;
    margin-left: 6px;
    overflow: hidden;
    line-height: 150%;
    text-overflow: ellipsis;
    white-space: nowrap;
}

/* 关闭 */
.tab-close {
    display: inline-block;
    width: 14px;
    height: 14px;
    margin-right: 2px;
    position: relative;
}

.tab-close::after,
.tab-close::before {
    position: absolute;
    top: 50%;
    right: 50%;
    transform: translate(50%, -50%) scale(0.9) rotate(45deg);
    content: "";
    width: 2px;
    height: 11px;
    border-radius: 3px;
    background-color: var(--tab-close-color);
}

.tab-close::before {
    transform: translate(50%, -50%) scale(0.9) rotate(-45deg);
}

/* 不同平台样式 */
body.win32 .nav ul {
    margin-left: 8px;
    margin-right: 186px;
}
body.win32 .browser {
    right: 140px;
}
body.darwin .nav ul {
    margin-left: 76px;
}
body.darwin.full-screen .nav ul {
    margin-left: 8px;
}

/* 暗黑模式 */
@media (prefers-color-scheme: dark) {
    :root {
        --tab-color: #C5C5C5;
        --tab-background: #3B3B3D;
        --tab-active-color: #E1E1E1;
        --tab-active-background: #575757;
        --tab-close-color: #E3E3E3;
    }
    .nav ul li.active::before {
        background-image: url(../image/dark/select_left.png);
    }

    .nav ul li.active::after {
        background-image: url(../image/dark/select_right.png);
    }

    .nav ul li.active .tab-icon.background {
        background-image: url(../image/dark/link_normal_selected_icon.png);
    }

    .browser span {
        background-image: url(../image/dark/link_normal_selected_icon.png);
    }

    .tab-icon.background {
        background-image: url(../image/dark/link_normal_icon.png);
    }
}