It seems that not everyone is keen on a dark theme (shocking I know) so I thought I'd use my SOCK to give the light theme some love.
As with the dark theme simply paste the following .css into the end of "<IIS site path>\Orion\styles\MainLayout.css" (nb. do not overwrite anything, simply paste it at the end and save). Once saved you must clear the cache on your browser then refresh any open pages:
/* The Following Was Added by Grays Solarwinds Orion Colourising Kit v1.4 05/16/2019 12:54:14 ~GSTG*/
.ResourceWrapper,.sw-pg-text,table,.chartDataNotAvailableArea,#discoveryCentral .noObjectsStyle,.CORE_Content,#tabPanel,#containerAdvancedDiv,.x-grid3-header,.x-panel-body,li.NodeGroupItem.SelectedNodeGroupItem,#NodeTree2 th,.apm_WizardContainer,#selectedTemplatesContainer,#resourcePickerLoader-content-ph>table,.layout-container,.portlet-header,.portletItem.shadow,.ext-strict .x-form-text,div.event-icon,.SAM_GettingStartedBox,.apm_GroupSection,.CloudMonitoring .GettingStarted>div,.noDataBackgroud div{background-color:Transparent!important;background-image:None!important;-webkit-box-shadow:none!important;-moz-box-shadow:none!important;box-shadow:none!important;background-url:none!important;background:transparent!important}.xui .xui-search__button.input-group-btn .xui-button,.x-combo-list-item,.x-panel-header,.x-panel-bbar .x-toolbar,.x-layout-split,.x-layout-collapsed{border:transparent!important}.HeaderBar{padding:6px!important}#chartDataNotAvailable,#apm_ThwackAd,.CloudMonitoring .GettingStarted .Content{border:2px solid #204a63!important;border-radius:10px!important;background:#215d9c!important;padding:15px 10px!important;color:#fff!important}#chartDataNotAvailable a,.sw-pg-hint-body-info,.sw-pg-hint-text{color:#fff!important}.CredentialTipsInstructions,.CredentialTipsInstructions a,.PI_off a,.xui .dropdown-menu li>a{color:#000!important}.chartDataNotAvailableArea{height:150px!important;padding-top:0!important}.Events,.Event,.Events td{background:none!important;border-bottom:#000 1px dashed}.xui .form-control,input,select{border:1px solid #000!important}.x-grid3-row-selected,div.x-grid3-row.x-grid3-row-alt.x-grid3-row-selected,div.x-grid3-row.x-grid3-row-selected{background-image:none!important}.NewContentBucket,.sw-hdr-title{box-shadow:none!important}.sw-suggestion{color:#8e6708!important;background:#fcf8e0!important;border:1px solid #d1bc6b!important}div.contAdminDateArea{padding:10px!important;border-radius:20px!important}.StatusIcon,.ModuleDetailsBlock img,.AuditEventMessage img,div.event-icon img,.NodeManagementIcons img,td.Property.NodeManagementIcons img,img#ctl00_ctl00_ctl00_BodyContent_ContentPlaceHolder1_ViewPageTitle_statusIconControl_NodeDetailsStatusIconLED,.sw-appstack-h>label>img,.containersTreeNode-statusIcon{border-radius:20px!important;background-color:white!important;padding:3px!important}.Disabled{opacity:.5!important}div#browseWrap.x-form-field-wrap.x-form-file-wrap{height:28px!important}ul.x-tab-strip li,.x-tab-panel-header,.x-tab-panel-footer,.xui .btn-default{border:none!important}.sw-forecast-warning,.sw-forecast-critical{color:black!important}.GroupBox,.GroupBoxAccounts,.blueBox,.ResourceContent,.formTable,#errorcontent,.sw-resource-wantedit>div>div,.x-grid3,.x-panel-bwrap,table.NodeManagement,.NewContentBucket,.sw-hdr-title,#adminContent * .column2of2,.sw-widget-drawer__filter-category,.ui-widget-content,.x-menu-list,.ManagementTaskDropdownContent ul,.ManagementTaskDropdown li.submenu,#cluetip-outer,.ui-dialog .ui-dialog-content,.sw-pref-options,.NodeManagement td,ul.NodeManagementMenu ul,#reportContentDialog div.ui-accordion-content,div#dataSourcePickerBox,div.SettingContainer,.ContentBucket,.x-window-tl,.x-window-ml,.x-window-mr,.x-window-mc,.sw-pg-login #dialog,.sw-widget-drawer__filter-panel--open .sw-widget-drawer__filter-panel,.sw-widget-drawer__list-container,.xui .list-group-item,table.axisOverview,tbody#EventsTableBody,table.Report.sw-pg-events{background-color:rgba(236,237,231,255)!important;color:rgba(62,110,89,255)!important}.SettingBlockDescription,.SettingBlockDescription span,.SettingContainer label,ul.ui-autocomplete.ui-menu.ui-widget.ui-widget-content.ui-corner-all a{color:rgba(62,110,89,255)!important}.GroupBox,.GroupBoxAccounts,.ResourceWrapper,#errorcontent,.NewContentBucket{border-bottom-right-radius:20px;border-bottom-left-radius:20px;-webkit-border-bottom-right-radius:20px;-webkit-border-bottom-left-radius:20px;-moz-border-radius-bottomright:20px;-moz-border-radius-bottomleft:20px;border-bottom-right-radius:20px;border-bottom-left-radius:20px}.ResourceContent,.formTable{border-bottom-left-radius:17px;border-bottom-right-radius:17px}hr,.x-tab-panel-header-plain .x-tab-strip-spacer,.x-tab-panel-footer-plain .x-tab-strip-spacer{background-color:rgba(231,232,237,255)!important}.HeaderBar h1 a,.expand_collapse_title,.key-header-name,#errorcontent,.NewBucketHeader,.sw-settings-rightbox-header,h2.PollerTypeTitle,.sw-pg-login #dialog label{color:rgba(110,65,62,255)!important;text-decoration:none!important}.HeaderBar,#leftpanel_filter,.h3noWrap{border-bottom-color:rgba(110,65,62,255)!important;background-color:rgba(231,232,237,255)!important}.GroupBox,.GroupBoxAccounts,.ResourceWrapper,#errorcontent,.NewContentBucket,table.NodeManagement,div#reportLayoutFooter,div#reportLayoutHeader,div#layoutBuilder,.SettingContainer,.tab-top{border:3px double rgba(215,215,215,255)!important}#NodeTree2,ul.NodeManagementMenu ul,li.submenu.over,.x-toolbar,.ContentBucket,.ElementGrouping,.x-panel-body,{border:solid 1px rgba(215,215,215,255)!important}.SettingBlockHeader{border-bottom:solid 1px rgba(215,215,215,255)!important}.ResourceWrapper a,.coloredLink,.sw-link{color:rgba(43,74,61,255)!important}.ResourceWrapper a:hover,.NodeManagementIcons a:hover,.coloredLink:hover,.sw-link:hover{opacity:.7!important;text-decoration:none!important}body,.xui body,.xui.xui-page-content--fill body .xui-page-wrapper .xui-content-area .xui-view .xui-page-content,.groupbox,.GroupBoxAccounts,#adminContent,.NodeManagementMenu li.submenu{background-image:url(data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAADIAAAAyCAMAAAAp4XiDAAAAGFBMVEX29vb19fXw8PDy8vL09PTz8/Pv7+/x8fGKuegbAAAAyUlEQVR42pXRQQ7CMBRDwST9pfe/MahEmgURbt7WmpVb6+vG0dd9REnn66xRy/qXiCgmEIIJhGACIZhACCYQgvlDCDFIEAwSBIMEwSBBMEgQDBIEgwTBIEEwCJEMQiSDENFMQmQzCZEbNyGemd6KeGZ6u4hnXe2qbdLHFjhf1XqNLXHev4wdMd9nspiEiWISJgqECQJhgkCYIBAmCIQJAmGCQJggECYJhAkCEUMEwhCBMEQgDJEIQ2RSg0iEIRJhiB/S+rrjqvXQ3paIJUgPBXxiAAAAAElFTkSuQmCC)!important;color:rgba(62,110,86,255)!important}.x-grid3-cell-inner,.AuditEventMessage,.xui .form-control,input,select,.cpRepeaterTable .leftLabelColumn,.xui .sw-notifications__list__item__link{color:rgba(62,110,86,255)!important}table.titleTable h1,div.titleTable h1{color:rgba(110,65,62,255)!important}.subNavContainer,.sw-dashboard__menu,tr.slider>td,.xui 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