3. CSS is Hard to learn
• So many property need to know
• Layout property is hard to realize
• How the cascade works
• So many selectors need to know
• Browser issue make developer crazy
3
4. CSS is pain
• NO Variables
• NO Math
• NO Functions
• NO Obvious Structure
• Repetitive, Repetitive and Repetitive
4
5. – CSS co-inventor, Bert Bos
CSS stops short of even more powerful features
that programmers use in their programming
languages: macros, variables, symbolic
constants, conditionals, expressions over
variables, etc. That is because these things give
power-users a lot of rope, but less experienced
users will unwittingly hang themselves; or, more
likely, be so scared that they won’t even touch
CSS. It’s a balance. And for CSS the balance is
different than for some other things.
5
6. – CSS co-inventor, Bert Bos
CSS stops short of even more powerful features
that programmers use in their programming
languages: macros, variables, symbolic
constants, conditionals, expressions over
variables, etc. That is because these things give
power-users a lot of rope, but less experienced
users will unwittingly hang themselves; or, more
likely, be so scared that they won’t even touch
CSS. It’s a balance. And for CSS the balance is
different than for some other things.
5
CSS 當初設計時
根本沒有考慮到當今 Web UI 排版的情況
⽽而是讓⼤大家好懂他的語法
38. #Removes quotes from a string.
unquote($string)
#Returns the number of characters in a string.
str-length($string)
#Converts a string to upper case.
to-upper-case($string)
#Converts a string to lower case.
to-lower-case($string)
37
String function