更新 'README.md'

README.md

@@ -107,7 +107,7 @@
 
 ### 颜色表
 
-- ![#f03c15](https://placehold.it/15/f03c15/000000?text=+) `#f03c15`
+- ![#f03c15](https://placehold.it/15/AliceBlue/000000?text=+) `#f03c15`
 - ![#c5f015](https://placehold.it/15/c5f015/000000?text=+) `#c5f015`
 - ![#1589F0](https://placehold.it/15/1589F0/000000?text=+) `#1589F0`
 <p style='color:red'>This is some red text.</p>