SharePoint site owners have new options for applying custom styles and colors to sites that make it easier to define and manage themes across site collections

ConnectSharePointOnline.ps1

# Commands to connect SharePoint Online 

$adminUPN="[email protected]"
$orgName= Read-Host -Prompt 'Name of your Office 365 organization, example: contoso'
$userCredential = Get-Credential -UserName $adminUPN -Message "Type the password."
Connect-SPOService -Url https://$orgName-admin.sharepoint.com -Credential $userCredential

# Verify SharePont Online Management Shell

Get-Module -Name Microsoft.Online.SharePoint.PowerShell -ListAvailable | Select Name,Version

SharePointSiteThemingScript.ps1

#Get all available 
Get-SPOTheme

#Get specific theme
Get-SPOTheme -Name "Custom Cyan" | ConvertTo-Json

#Queries the current SPOHideDefaultThemes setting
Get-SPOHideDefaultThemes

# Add new theme 
$themepalette = @{
  "themePrimary" = "#00ffff";
  "themeLighterAlt" = "#f3fcfc";
  "themeLighter" = "#daffff";
  "themeLight" = "#affefe";
  "themeTertiary" = "#76ffff";
  "themeSecondary" = "#39ffff";
  "themeDarkAlt" = "#00c4c4";
  "themeDark" = "#009090";
  "themeDarker" = "#005252";
  "neutralLighterAlt" = "#f8f8f8";
  "neutralLighter" = "#f4f4f4";
  "neutralLight" = "#eaeaea";
  "neutralQuaternaryAlt" = "#dadada";
  "neutralQuaternary" = "#d0d0d0";
  "neutralTertiaryAlt" = "#c8c8c8";
  "neutralTertiary" = "#a6a6a6";
  "neutralSecondaryAlt" = "#767676";
  "neutralSecondary" = "#666666";
  "neutralPrimary" = "#333";
  "neutralPrimaryAlt" = "#3c3c3c";
  "neutralDark" = "#212121";
  "black" = "#000000";
  "white" = "#fff";
  "primaryBackground" = "#fff";
  "primaryText" = "#333"
 }

Add-SPOTheme -Identity "Custom Theme Name" -Palette $themepalette -IsInverted $false

# Remove theme from gallery 
Remove-SPOTheme -Name "Custom Theme Name"

<#
References:

Theme generator 
https://developer.microsoft.com/en-us/fabric#/styles/themegenerator

Custom theming documentation 
https://support.office.com/en-us/article/Change-the-look-of-your-SharePoint-site-06bbadc3-6b04-4a60-9d14-894f6a170818

#>

VerifySharePointOnlineSetup.ps1

# Verify SharePont Online Management Shell

Get-Module -Name Microsoft.Online.SharePoint.PowerShell -ListAvailable | Select Name,Version

# To verify your setup
# If the cmdlet runs and returns False with no errors, as shown in the following example, you're ready to proceed.

Get-SPOHideDefaultThemes