Grundkonzepte

CSS Regeln:

   ELEMENT { property: value }

   BODY { background: white }

Selektoren und Deklarationen
Eigenschaften (properties) und Werte
Regeln in eigener Datei oder in HTML eingebettet

Gruppierung:

   H1, H2, H3 { font-family: helvetica }

   H4   { color: red;
          font-size: 8pt;
        }

Kontext:

   H1           { color: red }

   H1 EM        { color: purple }

   H1 EM STRONG { color: fuchsia }

Vererbung:

   BODY { font-family: helvetica }

   H1   { color: red;
          font-size: 14pt;
        }

z.B. Schriftfamilie wird auf enthaltene Elemente vererbt

Cascadierung:

   EM { font-style: italic }

   P EM { font-weight: bolder }

   STRONG EM { font-weight: bold }

   H1 EM { font-style: normal }

Elemente für die kein Stil definiert wird, werden mit dem Browser Default-Stil dargestellt.

Verknüpfung mit HTML

im LINK Element:

   <LINK rel="STYLESHEET" type="text/css"
   href="http://host/path/file.css">

im STYLE Element:

   <STYLE type="text/css">  
   H3 { color: lime }
   </STYLE>

mit @import:

   <STYLE type="text/css">  
   @import url(http://style.org/company.css)
   H1 { color: lime }
   </STYLE>

als Attribut:
```
   <P style="color: red" > Text </P> 
```
dies sollte man nicht machen

Element-Typen

Block-Elemente: BLOCKQUOTE, BR, DD, DL, DIV, DT, Hi, HR, HTML, LI, OBJECT, OL, P, PRE, UL
Inline-Elemente: A, EM, I, IMG, SPAN, STRONG, TT
Unsichtbare Elemente: LINK, META, STYLE, TITLE

Auswahl mit Bezeichnern

CLASS:

   H1.slide { color: lime }
   P.slide { color: green }
   .buch1 { color: yellow; background-color: black }

   <H1 class="slide">BlaBla</H1>
   <H1 class="buch1">BluBlu</H1>

ID:

   H1.#sp3 { color: aqua }

   <H1 id="sp3">BlaBla</H1>

Pseudo-Klassen:

   A:link    { color: red }  /* unvisited */
   A:visited { color: blue }
   A:active  { color: red }

Pseudo-Elemente:

   P:first-line   { color: fuchsia }  
   P:first-letter { color: red; background-color: lime }

Algorithmus der Cascadierung

entsprechend dem Selektor oder Vererbung
entsprechend dem Gewicht: !important
entsprechend dem Ursprung: Autor, Benutzer, Browser
entsprechend der Detail-Level (specificity)
entsprechend der Reihenfolge

Layout

Box-Eigenschaften: Füllung (padding), Rahmen (border), Rand (margin)

Box mit was drin

Schriften

Schrift: font

zusammenfassende Deklaration
Schrift-Familie: font-family

Helvetica, Times, Western, Courier

sans-serif, serif, fantasy, monospace
Schrift-Stil: font-style

normal, italic
Schrift-Variante: font-variant

normal, small-caps
Schrift-Gewicht: font-weight

normal, bold, lighter, 100, ..., 900 (sehr fett)
Schrift-Grösse: font-size

xx-small, x-small, small, medium, large, x-large, xx-large

12pt, 18pt, 150%, 0.5em

    P { font-family: monospace; 
        font-size: x-large; }

So siehts aus.

Farben

RGB-Farbmodell: Rot, Grün, Blau
bei Computer Bildschirmen
CMYK-Farbmodell: Cyan, Magenta, Yellow, Black
bei Farbdruckern

Farben:

black, silver, gray, white, maroon, red, purple, fuchsia, green, lime, olive, yellow, navy, blue, teal, aqua

rgb(rot,grün,blau), Werte: 0 <= rot, grün, blau <= 255, oder 0% <= rot, grün, blau <= 100%

#rgb, oder #rrggbb, Werte: 0 <= r, g, b <= F
Schriftfarbe: color
Hintergrundfarbe: background-color
Hintergrundbild: background-image

url(http://host/pfad/bild)

    P { color: blue }

Schwarz, Hellgrau, Grau, Weiß, Dunkelrot, Rot, Purpur, helles Purpur, Grün, Hellgrün, dunkles Grün, Gelb, Dunkelblau, Blau, Blaugrün, helles Grünblau (Cyan).

weitere Eigenschaften

Text-Eigenschaften:

word-spacing, text-decoration
Text-Ausrichtung:

vertical-align, text-align,
text-indent, line-height
Box-Eigenschaften:

margin,
margin-top, margin-right, margin-bottom, margin-left
padding,
border, border-color, border-style
width, height
Hintergrundbilder:

backround-image: url(...)
backround-repeat, backround-attachment,
backround-position

Beispiele vom W3C

HTML 2.0 in CSS1:

  /* Copyright (c) 1998 W3C */
  BODY { 
    margin: 1em;
    font-family: serif;
    line-height: 1.1;
    background: white;
    color: black; 
  }

  H1, H2, H3, H4, H5, H6, P, UL, OL, DIR, 
  MENU, DIV, DT, DD, ADDRESS, BLOCKQUOTE, 
  PRE, BR, HR { display: block }

  B, STRONG, I, EM, CITE, VAR, TT, CODE, KBD, SAMP, 
  IMG, SPAN { display: inline }

  LI { display: list-item }

  H1, H2, H3, H4 { margin-top: 1em; margin-bottom: 1em }
  H5, H6 { margin-top: 1em }
  H1 { text-align: center }
  H1, H2, H4, H6 { font-weight: bold }
  H3, H5 { font-style: italic }

  H1 { font-size: xx-large }
  H2 { font-size: x-large }
  H3 { font-size: large }

  B, STRONG { font-weight: bolder } /*relative to the parent*/
  I, CITE, EM, VAR, ADDRESS, BLOCKQUOTE { font-style: italic }
  PRE, TT, CODE, KBD, SAMP { font-family: monospace }

  PRE { white-space: pre }

  ADDRESS { margin-left: 3em }
  BLOCKQUOTE { margin-left: 3em; margin-right: 3em }

  UL, DIR { list-style: disc }
  OL { list-style: decimal }
  MENU { margin: 0 }              /* tight formatting */
  LI { margin-left: 3em }

  DT { margin-bottom: 0 }
  DD { margin-top: 0; margin-left: 3em }

  HR { border-top: solid } 

  A:link { color: blue }          /* unvisited link */
  A:visited { color: red }        /* visited links */
  A:active { color: lime }        /* active links */

  /* setting the anchor border around IMG elements
     requires contextual selectors */
  A:link IMG { border: 2px solid blue }
  A:visited IMG { border: 2px solid red }
  A:active IMG { border: 2px solid lime }

Moderner Stil: Seite, Style Sheet Inhalt:

    /* The W3C Core Styles Copyright (c) 1998 W3C */
    H1, H2, H3, H4, H5, H6, TH, DT { 
        font-family: Tahoma, Verdana, 
                     'Myriad Web', Syntax, sans-serif; 
        }

    P, DIV, UL, DL, DT, DD, PRE, OL, LI, 
    BLOCKQUOTE, ADDRESS {
        color: black;
        }

    A, ADDRESS, BLOCKQUOTE, BODY, CITE, CODE, DD, 
    DEL, DFN, DIV, DL, DT, EM, FORM, H1, H2, H3, 
    H4, H5, H6, IFRAME, IMG, KBD, LI, OBJECT, OL, 
    P, Q, SAMP, SMALL, SPAN, STRONG, SUB, SUP, UL, 
    VAR, APPLET, BIG, CENTER, DIR, FONT, HR, MENU, 
    PRE, ABBR, ACRONYM, BDO, BUTTON, FIELDSET, 
    INS, LABEL, LEGEND {       
        word-spacing:    normal;
        letter-spacing:  normal;
        text-transform:  none;
        text-decoration: none;
        border-color:    #036;
        border-style:    none;
        }       

    BODY {       
        color:      black;
        background: white;
        }       

    EM  {       
        font-style:  normal;
        font-weight: bold;
        color:       black;
        }       

    STRONG {       
        font-style:  italic;
        background:  white;
        font-weight: bold;
        color:       black;
        }       

    EM STRONG, STRONG EM    {       
        text-transform: uppercase;
        font-style:     normal;
        font-weight:    bolder;
        background:     white;
        color:          black;
        }       

    B {
        font-weight: bold;
        }

    I {
        font-style: italic;
        }

    .warning {       
        text-transform: none;
        font-style:     normal;
        font-weight:    bolder;
        background:     yellow;
        color:          black;
        }       

    DEL {       
        text-decoration: line-through;
        background:      #F66;
        }       

    INS {       
        text-decoration: none;
        background:      yellow;
        }       

    VAR, CITE, DFN, .note {       
        font-style: italic;
        }       

    ADDRESS {       
        font-style:     normal;
        letter-spacing: .1em;
        }       

    ACRONYM {       
        font-variant:   small-caps;
        letter-spacing: 0.1em;
        }       

    H1, H2, H3, H4, H5, H6, DT, LEGEND, 
    CAPTION, TH, THEAD, TFOOT {       
        color:      #036;
        background: white;
        }       

    HR {       
        color:  #036;
        }       

    #colophon {       
        display: none;
        }       

    CAPTION, COL, COLGROUP, TABLE, TBODY, TD, TR {       
        color:           black;
        text-decoration: none;
        border-color:    black;
        border-style:    none;
        background:      white;
        }       

    A:link {       
        text-decoration: none;
        font-weight:     bold;
        color:           #F30;
        background:      white;
        }       

    A:visited {       
        text-decoration: none;
        font-weight:     bold;
        color:           #996;
        background:      white;
        }       

    A:active {       
        text-decoration: none;
        font-weight:     bold;
        color:           #F30;
        background:      #FF0;
        }       

    A:hover {       
        text-decoration: none;
        color:           #F30;
        background:      white;
        }       

    A.offsite {       
        text-decoration: none;
        font-weight:     normal;
        color:           #C30;
        background:      white;
        }       

    BODY {
        margin-top:     1.58em;
        margin-left:    1.58em;
        margin-right:   1ex;
        margin-bottom:  1.58em;
        padding-top:    0;
        padding-left:   0;
        padding-right:  0;
        padding-bottom: 0;
        border-top:     0;
        border-left:    0;
        border-bottom:  0;
        border-right:   0;
        width:          auto;
        }

Style Sheet für HTML 4.0 in CSS2

Positionierung (CSS2)

Implementiert in Netscape 4.x, IE 4.0

Box-Position:
position: absolute, relative, static
left: length
top: length
height: length
width: length
z-index: integer
visibility: hidden, visible

Animation mit HTML, CSS, JavaScript und DOM

Dateien: HTML, CSS, JavaScript.

weitere Beispiele

Verdana Font:
@ Microsoft Gallery
Microsoft CSS Gallery:
Entrance
Genug ist Genug:
by Stephen Traub

Cascading Style Sheets (CSS)

Einordnung