improve docs

README.md

@@ -73,7 +73,7 @@ paru -S ttf-maple-beta
 
 The [`config.json`](./config.json) file is used to configure the build process. Checkout the [schema](./source/schema.json) for more details.
 
-There also have some command line options for customizing the build process. Cli options have higher priority than `config.json`.
+There also have some [command line options](#build-script-usage) for customizing the build process. Cli options have higher priority than options in `config.json`.
 
 ### Use Github Actions
 
@@ -107,13 +107,13 @@ python build.py
 
 - For `Ubuntu` or `Debian`, maybe `python-is-python3` is needed as well
 
-If you have trouble installing the dependencies, just create a new Github codespace on `variable` branch and run the commands there
+If you have trouble installing the dependencies, just create a new GitHub Codespace and run the commands there
 
 #### Custom Nerd-Font
 
 For custom `font-patcher` args, `font-forge` (and maybe `python3-fontforge` as well) is required.
 
-You should also change `nerd_font` config in `config.json`
+Maybe you should also change `"nerd_font.extra_args"` in [config.json](./config.json)
 
 #### Preset
 
@@ -121,9 +121,11 @@ Add `--normal` flag in `build.py` for common config, make the font just like `Je
 
 #### Font Feature Freeze
 
-- `enable`: Move ligature rules to `calt`, which will enable the features without setting up `cvXX` / `ssXX` / `zero` in font features config, just as default ligatures
-- `disable`: Remove the features in `cvXX` / `ssXX` / `zero`, which will no longer effect, even if you enable it manually
-- `ignore`: Do nothing
+There are three kind of options for feature freeze:
+
+1. `enable`: Move ligature rules to `calt`, which will enable the features without setting up `cvXX` / `ssXX` / `zero` in font features config, just as default ligatures
+2. `disable`: Remove the features in `cvXX` / `ssXX` / `zero`, which will no longer effect, even if you enable it manually
+3. `ignore`: Do nothing
 
 ### Chinese version