dark theme

// js
var worlaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaad = 'world!';
alert('Hello ' + worlaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaad);

<!--html-->
<h1>Hello world!</h1>

/* css */
h1 {
    font-size: 30px;
}

#include <stdio.h>
int main()
{
   // printf() 中字符串需要引号
   printf("Hello, World!");
   return 0;
}