Reset/remove CSS styles for element only
I'm sure this must have been mentioned/asked before but have been searching for an age with no luck, my terminology must be wrong!
I vaguely remember a tweet I saw a while ago that suggested there was a css rule available that would remove any styles previously set in the stylesheet for a particular element.
A good use example might be in a mobile-first RWD site where much of the styling used for a particular element in the small-screen views needs 'resetting' or removing for the same element in the desktop view.
A css rule that could achieve something like:
.element {
all: none;
}
Eaxmple usage:
/* mobile first */
.element {
margin: 0 10;
transform: translate3d(0, 0, 0);
z-index: 50;
display: block;
etc..
etc..
}
@media only screen and (min-width: 980px) {
.element {
all: none;
}
}
So we could quickly remove or re-set styling without having to declare every property.
Make sense?
The CSS3 keyword initial sets the CSS3 property to the initial value as defined in the spec. The initial keyword has broad browser support except for the IE and Opera Mini families.
Since IE's lack of support may cause issue here are some of the ways you can reset some CSS properties to their initial values:
.reset-this {
animation : none;
animation-delay : 0;
animation-direction : normal;
animation-duration : 0;
animation-fill-mode : none;
animation-iteration-count : 1;
animation-name : none;
animation-play-state : running;
animation-timing-function : ease;
backface-visibility : visible;
background : 0;
background-attachment : scroll;
background-clip : border-box;
background-color : transparent;
background-image : none;
background-origin : padding-box;
background-position : 0 0;
background-position-x : 0;
background-position-y : 0;
background-repeat : repeat;
background-size : auto auto;
border : 0;
border-style : none;
border-width : medium;
border-color : inherit;
border-bottom : 0;
border-bottom-color : inherit;
border-bottom-left-radius : 0;
border-bottom-right-radius : 0;
border-bottom-style : none;
border-bottom-width : medium;
border-collapse : separate;
border-image : none;
border-left : 0;
border-left-color : inherit;
border-left-style : none;
border-left-width : medium;
border-radius : 0;
border-right : 0;
border-right-color : inherit;
border-right-style : none;
border-right-width : medium;
border-spacing : 0;
border-top : 0;
border-top-color : inherit;
border-top-left-radius : 0;
border-top-right-radius : 0;
border-top-style : none;
border-top-width : medium;
bottom : auto;
box-shadow : none;
box-sizing : content-box;
caption-side : top;
clear : none;
clip : auto;
color : inherit;
columns : auto;
column-count : auto;
column-fill : balance;
column-gap : normal;
column-rule : medium none currentColor;
column-rule-color : currentColor;
column-rule-style : none;
column-rule-width : none;
column-span : 1;
column-width : auto;
content : normal;
counter-increment : none;
counter-reset : none;
cursor : auto;
direction : ltr;
display : inline;
empty-cells : show;
float : none;
font : normal;
font-family : inherit;
font-size : medium;
font-style : normal;
font-variant : normal;
font-weight : normal;
height : auto;
hyphens : none;
left : auto;
letter-spacing : normal;
line-height : normal;
list-style : none;
list-style-image : none;
list-style-position : outside;
list-style-type : disc;
margin : 0;
margin-bottom : 0;
margin-left : 0;
margin-right : 0;
margin-top : 0;
max-height : none;
max-width : none;
min-height : 0;
min-width : 0;
opacity : 1;
orphans : 0;
outline : 0;
outline-color : invert;
outline-style : none;
outline-width : medium;
overflow : visible;
overflow-x : visible;
overflow-y : visible;
padding : 0;
padding-bottom : 0;
padding-left : 0;
padding-right : 0;
padding-top : 0;
page-break-after : auto;
page-break-before : auto;
page-break-inside : auto;
perspective : none;
perspective-origin : 50% 50%;
position : static;
/* May need to alter quotes for different locales (e.g fr) */
quotes : '201C' '201D' '2018' '2019';
right : auto;
tab-size : 8;
table-layout : auto;
text-align : inherit;
text-align-last : auto;
text-decoration : none;
text-decoration-color : inherit;
text-decoration-line : none;
text-decoration-style : solid;
text-indent : 0;
text-shadow : none;
text-transform : none;
top : auto;
transform : none;
transform-style : flat;
transition : none;
transition-delay : 0s;
transition-duration : 0s;
transition-property : none;
transition-timing-function : ease;
unicode-bidi : normal;
vertical-align : baseline;
visibility : visible;
white-space : normal;
widows : 0;
width : auto;
word-spacing : normal;
z-index : auto;
/* basic modern patch */
all: initial;
all: unset;
}
/* basic modern patch */
#reset-this-root {
all: initial;
* {
all: unset;
}
}
As mentioned in a comment by @user566245 :
this is correct in principle, but individual mileage may vary. For example certain elements like textarea by default have a border, applying this reset will render those textarea's border less.
[POST EDIT FEB 4, '17] Upvoted for becoming a modern norm, user Joost
#reset-this-parent {
all: initial;
* {
all: unset;
}
}
EXAMPLE FROM W3
For example, if an author specifies all: initial on an element it will block all inheritance and reset all properties, as if no rules appeared in the author, user, or user-agent levels of the cascade.
This can be useful for the root element of a "widget" included in a page, which does not wish to inherit the styles of the outer page. Note, however, that any "default" style applied to that element (such as, eg display: block from the UA style sheet on block elements such as ) will also be blown away.
JAVASCRIPT ?
Nobody thought about other than css to reset css? Yes?
There is that snip fully relevant : https://stackoverflow.com/a/14791113/845310
getElementsByTagName("*") will return all elements from DOM. Then you may set styles for each element in the collection:
answered Feb 9 '13 at 20:15 by VisioN
var allElements = document.getElementsByTagName("*");
for (var i = 0, len = allElements.length; i < len; i++) {
var element = allElements[i];
// element.style.border = ...
}
With all this said; i don't think a css reset is something feasable unless we end up with only one web browser .. if the 'default' is set by browser in the end.
For comparison, here is Firefox 40.0 values list for a <blockquote style="all: unset;font-style: oblique"> where font-style: oblique triggers DOM operation.
align-content: unset;
align-items: unset;
align-self: unset;
animation: unset;
appearance: unset;
backface-visibility: unset;
background-blend-mode: unset;
background: unset;
binding: unset;
block-size: unset;
border-block-end: unset;
border-block-start: unset;
border-collapse: unset;
border-inline-end: unset;
border-inline-start: unset;
border-radius: unset;
border-spacing: unset;
border: unset;
bottom: unset;
box-align: unset;
box-decoration-break: unset;
box-direction: unset;
box-flex: unset;
box-ordinal-group: unset;
box-orient: unset;
box-pack: unset;
box-shadow: unset;
box-sizing: unset;
caption-side: unset;
clear: unset;
clip-path: unset;
clip-rule: unset;
clip: unset;
color-adjust: unset;
color-interpolation-filters: unset;
color-interpolation: unset;
color: unset;
column-fill: unset;
column-gap: unset;
column-rule: unset;
columns: unset;
content: unset;
control-character-visibility: unset;
counter-increment: unset;
counter-reset: unset;
cursor: unset;
display: unset;
dominant-baseline: unset;
empty-cells: unset;
fill-opacity: unset;
fill-rule: unset;
fill: unset;
filter: unset;
flex-flow: unset;
flex: unset;
float-edge: unset;
float: unset;
flood-color: unset;
flood-opacity: unset;
font-family: unset;
font-feature-settings: unset;
font-kerning: unset;
font-language-override: unset;
font-size-adjust: unset;
font-size: unset;
font-stretch: unset;
font-style: oblique;
font-synthesis: unset;
font-variant: unset;
font-weight: unset;
font: ;
force-broken-image-icon: unset;
height: unset;
hyphens: unset;
image-orientation: unset;
image-region: unset;
image-rendering: unset;
ime-mode: unset;
inline-size: unset;
isolation: unset;
justify-content: unset;
justify-items: unset;
justify-self: unset;
left: unset;
letter-spacing: unset;
lighting-color: unset;
line-height: unset;
list-style: unset;
margin-block-end: unset;
margin-block-start: unset;
margin-inline-end: unset;
margin-inline-start: unset;
margin: unset;
marker-offset: unset;
marker: unset;
mask-type: unset;
mask: unset;
max-block-size: unset;
max-height: unset;
max-inline-size: unset;
max-width: unset;
min-block-size: unset;
min-height: unset;
min-inline-size: unset;
min-width: unset;
mix-blend-mode: unset;
object-fit: unset;
object-position: unset;
offset-block-end: unset;
offset-block-start: unset;
offset-inline-end: unset;
offset-inline-start: unset;
opacity: unset;
order: unset;
orient: unset;
outline-offset: unset;
outline-radius: unset;
outline: unset;
overflow: unset;
padding-block-end: unset;
padding-block-start: unset;
padding-inline-end: unset;
padding-inline-start: unset;
padding: unset;
page-break-after: unset;
page-break-before: unset;
page-break-inside: unset;
paint-order: unset;
perspective-origin: unset;
perspective: unset;
pointer-events: unset;
position: unset;
quotes: unset;
resize: unset;
right: unset;
ruby-align: unset;
ruby-position: unset;
scroll-behavior: unset;
scroll-snap-coordinate: unset;
scroll-snap-destination: unset;
scroll-snap-points-x: unset;
scroll-snap-points-y: unset;
scroll-snap-type: unset;
shape-rendering: unset;
stack-sizing: unset;
stop-color: unset;
stop-opacity: unset;
stroke-dasharray: unset;
stroke-dashoffset: unset;
stroke-linecap: unset;
stroke-linejoin: unset;
stroke-miterlimit: unset;
stroke-opacity: unset;
stroke-width: unset;
stroke: unset;
tab-size: unset;
table-layout: unset;
text-align-last: unset;
text-align: unset;
text-anchor: unset;
text-combine-upright: unset;
text-decoration: unset;
text-emphasis-position: unset;
text-emphasis: unset;
text-indent: unset;
text-orientation: unset;
text-overflow: unset;
text-rendering: unset;
text-shadow: unset;
text-size-adjust: unset;
text-transform: unset;
top: unset;
transform-origin: unset;
transform-style: unset;
transform: unset;
transition: unset;
user-focus: unset;
user-input: unset;
user-modify: unset;
user-select: unset;
vector-effect: unset;
vertical-align: unset;
visibility: unset;
white-space: unset;
width: unset;
will-change: unset;
window-dragging: unset;
word-break: unset;
word-spacing: unset;
word-wrap: unset;
writing-mode: unset;
z-index: unset;
For future readers. I think this is what was meant but currently isn't really wide supported (see below):
#someselector {
all: initial;
* {
all: unset;
}
}
Let me answer this question thoroughly, because it's been a source of pain for me for several years and very few people really understand the problem and why it's important for it to be solved. If I were at all responsible for the CSS spec I'd be embarrassed, frankly, for having not addressed this in the last decade.
The Problem
You need to insert markup into an HTML document, and it needs to look a specific way. Furthermore, you do not own this document, so you cannot change existing style rules. You have no idea what the style sheets could be, or what they may change to.
Use cases for this are when you are providing a displayable component for unknown 3rd party websites to use. Examples of this would be:
Simplest Fix
Put everything in an iframe. This has it's own set of limitations:
If your content can fit into a box, you can get around problem #1 by having your content write an iframe and explicitly set the content, thus skirting around the issue, since the iframe and document will share the same domain.
CSS Solution
I've search far and wide for the solution to this, but there are unfortunately none. The best you can do is explicitly override all possible properties that can be overridden, and override them to what you think their default value should be.
Even when you override, there is no way to ensure a more targeted CSS rule won't override yours. The best you can do here is to have your override rules target as specifically as possible and hope the parent document doesn't accidentally best it: use an obscure or random ID on your content's parent element, and use !important on all property value definitions.
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