WordPress, the most popular blogging platform, is highly customizable. With its many options and a vast ecosystem of themes, plugins, and widgets, you can design down to the pixel the blogs and websites you want.
Blogger, Google’s blogging platform, is the underdog. It’s easy to start a blog with Blogger. As for design, it has a few tricks up its sleeve, too. For example, in addition to a basic selection of themes and widgets, you can create custom themes. And tweak typography with a huge assortment of fonts. An article below discusses just this.