border-left

O propriedade border-left CSS é um atalho que define os valores de border-left-color, border-left-style, e border-left-width. Estas propriedades descrevem a borda esquerda de elementos.

Os três valores da propriedade estenográfica pode ser especificada em qualquer ordem, e um ou dois deles podem ser omitidos.

  border-left-style: dotted;
  border-left: thick green;

  border-left-style: dotted;
  border-left: none thick green;

border-left: 1px;
border-left: 2px dotted;
border-left: medium dashed green;

<br-width> 

Veja border-left-width.

<br-style> 

Veja border-left-style.

<color> 

Veja border-left-color.

<line-width> || <line-style> || <color>
where 
<line-width> = <length> | thin | medium | thick
<line-style> = none | hidden | dotted | dashed | solid | double | groove | ridge | inset | outset
<color> = <rgb()> | <rgba()> | <hsl()> | <hsla()> | <hex-color> | <named-color> | currentcolor | <deprecated-system-color>
where 
<rgb()> = rgb( <percentage>{3} [ / <alpha-value> ]? ) | rgb( <number>{3} [ / <alpha-value> ]? ) | rgb( <percentage>#{3} , <alpha-value>? ) | rgb( <number>#{3} , <alpha-value>? )
<rgba()> = rgba( <percentage>{3} [ / <alpha-value> ]? ) | rgba( <number>{3} [ / <alpha-value> ]? ) | rgba( <percentage>#{3} , <alpha-value>? ) | rgba( <number>#{3} , <alpha-value>? )
<hsl()> = hsl( <hue> <percentage> <percentage> [ / <alpha-value> ]? ) | hsl( <hue>, <percentage>, <percentage>, <alpha-value>? )
<hsla()> = hsla( <hue> <percentage> <percentage> [ / <alpha-value> ]? ) | hsla( <hue>, <percentage>, <percentage>, <alpha-value>? )
where 
<alpha-value> = <number> | <percentage>
<hue> = <number> | <angle>

<div class='box'>
  <p>This box has a border on the left side.</p>
</div>

.box {
  background-color: #ffaabb;
  border-left: 4px solid #000;
  height: 100px;
  width: 100px;
}

.box p {
  font-weight: bold;
  text-align: center;
}