發送短信 : Why do we choose the color red for danger?

 _    _    __   __    _____      ___      ____    
| \  / ||  \ \\/ //  / ____||   / _ \\   |  _ \\  
|  \/  ||   \ ` //  / //---`'  | / \ ||  | |_| || 
| .  . ||    | ||   \ \\___    | \_/ ||  | .  //  
|_|\/|_||    |_||    \_____||   \___//   |_|\_\\  
`-`  `-`     `-`'     `----`    `---`    `-` --`