Develop the site design in SharePoint
Find links to information about using Design Manager and implementing a design for your SharePoint site. If you want your SharePoint site to represent your organization's brand and not "look like SharePoint," you can create a custom design and use Design Manager to achieve that goal. Design Manager is a feature in SharePoint that makes it easier to create a fully customized, pixel-perfect design while using the web-design tools that you're already familiar with. Design Manager is a publishing feature that is available in publishing sites in both SharePoint and Office 365. You can also use Design Manager to brand the public-facing website in Office 365.
This extensibility option is only available for classic SharePoint experiences. You cannot use this option with modern experiences in SharePoint Online, like with communication sites. We do not recommend using classic experience or these branding techniques anymore.
For more information about using Design Manager to customize your sites, see the following articles and their subtopics:
Overview of Design Manager in SharePoint : Get an overview of using Design Manager to brand your SharePoint site. Design Manager is a publishing feature that is available in publishing sites in both SharePoint and Office 365.
Overview of the SharePoint page model : Learn about the revised page model—including master pages and page layouts—redesigned for SharePoint.
Master pages, the Master Page Gallery, and page layouts in SharePoint : Find links to information about using Design Manager to work with master pages, page layouts, and display templates in publishing sites in SharePoint.
SharePoint Design Manager branding and design capabilities : Find links to information about using Design Manager branding and design capabilities in SharePoint.