On the problem that negative values of outline-offset cannot form a plus sign in firefox browsers

problem description

outline-offset takes a negative value in Google, and a plus sign can be formed at a critical point, but in the lower right of the center of the box in firefox and hbuilder, I checked on the Internet and did not see the answer in this respect. Please give me some advice

.

related codes

.cross {

width: 100px;
height: 100px;
border: 1px solid -sharpccc;
outline: 20px solid -sharpccc;
outline-offset: -70px;

}
< div class= "cross" > < / div >

what result do you expect? What is the error message actually seen?

Google browser rendering results:
clipboard.png

hbuilder:
clipboard.png

in the end, I had no choice but to use the plus sign of the background image to implement this style, but I wonder which god can answer

Oct.26,2021
MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-49c94db-1d564.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-49c94db-1d564.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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