docs: improve home page

Signed-off-by: Gerard Marull-Paretas <gerard@teslabs.com>

docs/_static/css/custom.css

@@ -31,6 +31,6 @@ html {
   --pst-font-family-heading: "Tomorrow", sans-serif;
 }
 
-.caption, .logo__title {
+.caption, .logo__title, .home-title {
   font-family: "Tomorrow", sans-serif;
 }

docs/index.md

@@ -1,4 +1,86 @@
-# Welcome to the PebbleOS documentation!
+```{raw} html
+<div style="display: none;">
+```
+# PebbleOS documentation
+```{raw} html
+</div>
+```
+
+::::{grid} 2
+:reverse:
+
+:::{grid-item}
+:columns: 4
+:class: sd-m-auto
+
+<img src="_static/images/logo.svg" />
+
+:::
+
+:::{grid-item}
+:columns: 8
+
+```{div} sd-fs-3 home-title
+Welcome to the PebbleOS documentation site!
+```
+
+PebbleOS is a lightweight, power-efficient operating system originally developed for Pebble smartwatches and now [released open source](https://opensource.googleblog.com/2025/01/see-code-that-powered-pebble-smartwatches.html).
+It supports custom watchfaces and apps using C and JavaScript.
+Optimized for memory-in-pixel (MIP) displays and long battery life, it features Bluetooth sync, a timeline interface, and a strong developer ecosystem through an open SDK.
+
+```{button-ref} getting_started
+:ref-type: doc
+:color: primary
+:class: sd-rounded-pill float-left
+
+Get started
+```
+
+```{only} html
+[![](https://img.shields.io/github/stars/pebble-dev/pebble-firmware?style=social)](https://github.com/pebble-dev/pebble-firmware)
+```
+
+:::
+
+::::
+
+::::{grid} 1 1 2 3
+:class-container: text-center
+:gutter: 3
+
+:::{grid-item-card}
+:link: getting_started
+:link-type: doc
+:class-header: bg-light
+
+🚀 Getting Started
+^^^
+
+Learn how to build PebbleOS from source!
+:::
+
+:::{grid-item-card}
+:link: https://github.com/pebble-dev/pebble-firmware
+:class-header: bg-light
+
+⌚ Browse the sources
+^^^
+
+Browse the PebbleOS sources!
+:::
+
+:::{grid-item-card}
+:link: reference/external
+:link-type: doc
+:class-header: bg-light
+
+📖 Reference
+^^^
+
+Learn more about PebbleOS: podcasts, developer documents and more!
+:::
+
+::::
 
 ```{toctree}
 :hidden: