what should be wrote at the start of every css? - css

Question

Hello I'm just starting with css and I see people in videos and such already have css code written before they write a single line of code like:
body {
padding:0;
margin:0;
}
this is like a really simple example they write like body,div,table..etc like the a:active and stuff like that but like in like really long code they even add a selected attribute so when you selected any words on the page the background and color changes I know this depends from one developer or another but is there a really basic piece of code that I can start with?

Answer 1

People prefer different ways of working with CSS, there is no right or wrong way. But there is certainly ways to get a good head start with your browser resets.
There are a few ways to play it, you can either use a reset or normalise your code to fit the different browsers.
A reset will make everything behave in streamlined way across each browser, whereas normalising your css will make browsers render all elements more consistently and in line with modern standards.
Rememeber there is no right or wrong way to approach this.
Eric Meyes CSS Reset
Normalize.css

Answer 2

it is all just style and opinion, but this is often used and resets just about everything (so you'd have to create all your styles yourself, instead of using browser defaults).
html, body, div, span, object, iframe,
h1, h2, h3, h4, h5, h6, p, blockquote, pre,
abbr, address, cite, code,
del, dfn, em, img, ins, kbd, q, samp,
small, strong, sub, sup, var,
b, i,
dl, dt, dd, ol, ul, li,
fieldset, form, label, legend,
table, caption, tbody, tfoot, thead, tr, th, td,
article, aside, canvas, details, figcaption, figure,
footer, header, hgroup, menu, nav, section, summary,
time, mark, audio, video {
margin:0;
padding:0;
border:0;
outline:0;
font-size:100%;
vertical-align:baseline;
background:transparent;
}
body {
line-height:1;
}
article,aside,details,figcaption,figure,
footer,header,hgroup,menu,nav,section {
display:block;
}
nav ul {
list-style:none;
}
blockquote, q {
quotes:none;
}
blockquote:before, blockquote:after,
q:before, q:after {
content:'';
content:none;
}
a {
margin:0;
padding:0;
font-size:100%;
vertical-align:baseline;
background:transparent;
}
/* change colours to suit your needs */
ins {
background-color:#ff9;
color:#000;
text-decoration:none;
}
/* change colours to suit your needs */
mark {
background-color:#ff9;
color:#000;
font-style:italic;
font-weight:bold;
}
del {
text-decoration: line-through;
}
abbr[title], dfn[title] {
border-bottom:1px dotted;
cursor:help;
}
table {
border-collapse:collapse;
border-spacing:0;
}
/* change border colour to suit your needs */
hr {
display:block;
height:1px;
border:0;
border-top:1px solid #cccccc;
margin:1em 0;
padding:0;
}
input, select {
vertical-align:middle;
}