修改element-ui日期下拉框datetimePicker的背景色样式

如图： 

1、修改背景色

.el-date-picker.has-sidebar.has-time {

    background: #04308D;

    color: #fff;

    border: 1px solid #326AFF

}

.el-date-picker__header-label {

    color: #ffffff;

}

.el-date-table th {

    color: #fff;

}

.el-icon-d-arrow-left:before {

    color: #fff;

}

.el-icon-arrow-left:before {

    color: #fff;

}

.el-icon-arrow-right:before {

    color: #fff;

}

.el-icon-d-arrow-right:before {

    color: #fff;

}

.el-picker-panel__footer {

    background-color: #04308D;

    border: 1px solid #326AFF

}

.el-picker-panel [slot=sidebar], .el-picker-panel__sidebar {

    background-color: #04308D;

    border-right: 1px solid #326AFF;

}

.el-picker-panel__shortcut {

    color: #fff;

}

.el-date-picker__time-header {

    border-bottom: 1px solid #326AFF;

}

.el-popper[x-placement^=bottom] .popper__arrow::after {

    top: 1px;

    margin-left: -6px;

    border-top-width: 0;

    border-bottom-color: #04308D;

}

.el-popper[x-placement^=top] .popper__arrow::after {

    bottom: 1px;

    margin-left: -6px;

    border-top-color: #326AFF;

    border-bottom-width: 0;

}

.el-picker-panel {

    background: #04308D;

    color: #fff;

}

.el-date-table td.in-range div, .el-date-table td.in-range div:hover, .el-date-table.is-week-mode .el-date-table__row.current div, .el-date-table.is-week-mode .el-date-table__row:hover div {

    background-color: #326AFFc9;

}

.el-date-range-picker__time-header{

    border-bottom: 1px solid #326AFF;

}

.el-date-range-picker__content.is-left{

    border-right: 1px solid #326AFF;

}

2、修改输入框

.el-input__wrapper {

    border: 1px solid #326AFF;

    box-shadow: 0 0 0 0px #326AFF inset;

    background: #04308D !important;

}

.el-input__wrapper .el-input__inner {

    background: #04308D !important;

    font-size: 14px;

    font-weight: 400;

    color: #FFFFFF;

}

 3、修改三角号的背景色和边框

.el-popper.is-light .el-popper__arrow::before {

    border: 1px solid #326AFF;

    background: #04308D;

    right: 0;

}

.el-popper.is-pure {

    border:  1px solid #326AFF;

}

4、修改下一天下一年按钮颜色

.el-picker-panel__icon-btn{

    color: #fff;

}

5、修改选中日期的字体颜色

.in-range{

    color: #326aff;

}

6、最下面按钮

.el-picker-panel__footer .el-button.is-text {

    color: #fff;

    border: 0 solid transparent;

    background-color: transparent;

}

.el-picker-panel__footer .el-button{

    background-color: #326aff;

    border: 1px solid #326AFF;

    color: #fff;

}

.el-button.is-text:not(.is-disabled):hover {

    background-color: #326aff;

}

7、全部代码

.el-date-picker.has-sidebar.has-time {background: #04308D;color: #fff;border: 1px solid #326AFF
}
.el-date-picker__header-label {color: #ffffff;
}
.el-date-table th {color: #fff;
}
.el-icon-d-arrow-left:before {color: #fff;
}
.el-icon-arrow-left:before {color: #fff;
}
.el-icon-arrow-right:before {color: #fff;
}
.el-icon-d-arrow-right:before {color: #fff;
}
.el-picker-panel__footer {background-color: #04308D;border: 1px solid #326AFF
}
.el-picker-panel [slot=sidebar], .el-picker-panel__sidebar {background-color: #04308D;border-right: 1px solid #326AFF;
}
.el-picker-panel__shortcut {color: #fff;
}
.el-date-picker__time-header {border-bottom: 1px solid #326AFF;
}
.el-popper[x-placement^=bottom] .popper__arrow::after {top: 1px;margin-left: -6px;border-top-width: 0;border-bottom-color: #04308D;
}
.el-popper[x-placement^=top] .popper__arrow::after {bottom: 1px;margin-left: -6px;border-top-color: #326AFF;border-bottom-width: 0;
}
.el-picker-panel {background: #04308D;color: #fff;
}
.el-date-table td.in-range div, .el-date-table td.in-range div:hover, .el-date-table.is-week-mode .el-date-table__row.current div, .el-date-table.is-week-mode .el-date-table__row:hover div {background-color: #326AFFc9;
}
.el-date-range-picker__time-header{border-bottom: 1px solid #326AFF;
}
.el-date-range-picker__content.is-left{border-right: 1px solid #326AFF;
}
//三角号
.el-popper.is-light .el-popper__arrow::before {border: 1px solid #326AFF;background: #04308D;right: 0;
}
.el-popper.is-pure {border:  1px solid #326AFF;
}
.el-input__wrapper {border: 1px solid #326AFF;box-shadow: 0 0 0 0px #326AFF inset;background: #04308D !important;}.el-input__wrapper .el-input__inner {background: #04308D !important;font-size: 14px;font-weight: 400;color: #FFFFFF;
}
// 下方按钮
.el-picker-panel__footer .el-button.is-text {color: #fff;border: 0 solid transparent;background-color: transparent;
}
.el-picker-panel__footer .el-button{background-color: #326aff;border: 1px solid #326AFF;color: #fff;
}
.el-button.is-text:not(.is-disabled):hover {background-color: #326aff;
}
.in-range{color: #326aff;}

 放到assets里面间一个scss文件

main.js引用即可全局使用