dify/web/app/styles/preflight.css

/*
1. Prevent padding and border from affecting element width. (https://github.com/mozdevs/cssremedy/issues/4)
2. Allow adding a border to an element by just adding a border-width. (https://github.com/tailwindcss/tailwindcss/pull/116)
*/

*,
::before,
::after {
  box-sizing: border-box; /* 1 */
  border-width: 0; /* 2 */
  border-style: solid; /* 2 */
  border-color: theme('borderColor.DEFAULT', currentColor); /* 2 */
}

::before,
::after {
  --tw-content: '';
}

/*
1. Use a consistent sensible line-height in all browsers.
2. Prevent adjustments of font size after orientation changes in iOS.
3. Use a more readable tab size.
4. Use the user's configured `sans` font-family by default.
5. Use the user's configured `sans` font-feature-settings by default.
6. Use the user's configured `sans` font-variation-settings by default.
7. Disable tap highlights on iOS
*/

html,
:host {
  line-height: 1.5; /* 1 */
  -webkit-text-size-adjust: 100%; /* 2 */
  -moz-tab-size: 4; /* 3 */
  tab-size: 4; /* 3 */
  font-family: theme('fontFamily.sans', ui-sans-serif, system-ui, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji"); /* 4 */
  -webkit-tap-highlight-color: transparent; /* 7 */
}

/*
1. Remove the margin in all browsers.
2. Inherit line-height from `html` so users can set them as a class directly on the `html` element.
*/

body {
  margin: 0; /* 1 */
  line-height: inherit; /* 2 */
}

/*
1. Add the correct height in Firefox.
2. Correct the inheritance of border color in Firefox. (https://bugzilla.mozilla.org/show_bug.cgi?id=190655)
3. Ensure horizontal rules are visible by default.
*/

hr {
  height: 0; /* 1 */
  color: inherit; /* 2 */
  border-top-width: 1px; /* 3 */
}

/*
Add the correct text decoration in Chrome, Edge, and Safari.
*/

abbr:where([title]) {
  text-decoration: underline dotted;
}

/*
Remove the default font size and weight for headings.
*/

h1,
h2,
h3,
h4,
h5,
h6 {
  font-size: inherit;
  font-weight: inherit;
}

/*
Reset links to optimize for opt-in styling instead of opt-out.
*/

a {
  color: inherit;
  text-decoration: inherit;
}

/*
Add the correct font weight in Edge and Safari.
*/

b,
strong {
  font-weight: bolder;
}

/*
1. Use the user's configured `mono` font-family by default.
2. Use the user's configured `mono` font-feature-settings by default.
3. Use the user's configured `mono` font-variation-settings by default.
4. Correct the odd `em` font sizing in all browsers.
*/

code,
kbd,
samp,
pre {
  font-family: theme('fontFamily.mono', ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace); /* 1 */
  font-size: 1em; /* 4 */
}

/*
Add the correct font size in all browsers.
*/

small {
  font-size: 80%;
}

/*
Prevent `sub` and `sup` elements from affecting the line height in all browsers.
*/

sub,
sup {
  font-size: 75%;
  line-height: 0;
  position: relative;
  vertical-align: baseline;
}

sub {
  bottom: -0.25em;
}

sup {
  top: -0.5em;
}

/*
1. Remove text indentation from table contents in Chrome and Safari. (https://bugs.chromium.org/p/chromium/issues/detail?id=999088, https://bugs.webkit.org/show_bug.cgi?id=201297)
2. Correct table border color inheritance in all Chrome and Safari. (https://bugs.chromium.org/p/chromium/issues/detail?id=935729, https://bugs.webkit.org/show_bug.cgi?id=195016)
3. Remove gaps between table borders by default.
*/

table {
  text-indent: 0; /* 1 */
  border-color: inherit; /* 2 */
  border-collapse: collapse; /* 3 */
}

/*
1. Change the font styles in all browsers.
2. Remove the margin in Firefox and Safari.
3. Remove default padding in all browsers.
*/

button,
input,
optgroup,
select,
textarea {
  font-family: inherit; /* 1 */
  font-feature-settings: inherit; /* 1 */
  font-variation-settings: inherit; /* 1 */
  font-size: 100%; /* 1 */
  font-weight: inherit; /* 1 */
  line-height: inherit; /* 1 */
  letter-spacing: inherit; /* 1 */
  color: inherit; /* 1 */
  margin: 0; /* 2 */
  padding: 0; /* 3 */
}

/*
Remove the inheritance of text transform in Edge and Firefox.
*/

button,
select {
  text-transform: none;
}

/*
1. Correct the inability to style clickable types in iOS and Safari.
2. Remove default button styles.
*/

button {
  -webkit-appearance: button; /* 1 */
  background-color: transparent; /* 2 */
  background-image: none; /* 2 */
}

/*
Use the modern Firefox focus style for all focusable elements.
*/

:-moz-focusring {
  outline: auto;
}

/*
Remove the additional `:invalid` styles in Firefox. (https://github.com/mozilla/gecko-dev/blob/2f9eacd9d3d995c937b4251a5557d95d494c9be1/layout/style/res/forms.css#L728-L737)
*/

:-moz-ui-invalid {
  box-shadow: none;
}

/*
Add the correct vertical alignment in Chrome and Firefox.
*/

progress {
  vertical-align: baseline;
}

/*
Correct the cursor style of increment and decrement buttons in Safari.
*/

::-webkit-inner-spin-button,
::-webkit-outer-spin-button {
  height: auto;
}

/*
1. Correct the odd appearance in Chrome and Safari.
2. Correct the outline style in Safari.
*/

[type='search'] {
  -webkit-appearance: textfield; /* 1 */
  outline-offset: -2px; /* 2 */
}

/*
Remove the inner padding in Chrome and Safari on macOS.
*/

::-webkit-search-decoration {
  -webkit-appearance: none;
}

/*
1. Correct the inability to style clickable types in iOS and Safari.
2. Change font properties to `inherit` in Safari.
*/

::-webkit-file-upload-button {
  -webkit-appearance: button; /* 1 */
  font: inherit; /* 2 */
}

/*
Add the correct display in Chrome and Safari.
*/

summary {
  display: list-item;
}

/*
Removes the default spacing and border for appropriate elements.
*/

blockquote,
dl,
dd,
h1,
h2,
h3,
h4,
h5,
h6,
hr,
figure,
p,
pre {
  margin: 0;
}

fieldset {
  margin: 0;
  padding: 0;
}

legend {
  padding: 0;
}

ol,
ul,
menu {
  list-style: none;
  margin: 0;
  padding: 0;
}

/*
Reset default styling for dialogs.
*/
dialog {
  padding: 0;
}

/*
Prevent resizing textareas horizontally by default.
*/

textarea {
  resize: vertical;
}

/*
1. Reset the default placeholder opacity in Firefox. (https://github.com/tailwindlabs/tailwindcss/issues/3300)
2. Set the default placeholder color to the user's configured gray 400 color.
*/

input::placeholder,
textarea::placeholder {
  opacity: 1; /* 1 */
  color: theme('colors.gray.400', #9ca3af); /* 2 */
}

/*
Set the default cursor for buttons.
*/

button,
[role="button"] {
  cursor: pointer;
}

/*
Make sure disabled buttons don't get the pointer cursor.
*/
:disabled {
  cursor: default;
}

/*
1. Make replaced elements `display: block` by default. (https://github.com/mozdevs/cssremedy/issues/14)
2. Add `vertical-align: middle` to align replaced elements more sensibly by default. (https://github.com/jensimmons/cssremedy/issues/14#issuecomment-634934210)
   This can trigger a poorly considered lint error in some tools but is included by design.
*/

img,
svg,
video,
canvas,
audio,
iframe,
embed,
object {
  display: block; /* 1 */
  vertical-align: middle; /* 2 */
}

/*
Constrain images and videos to the parent width and preserve their intrinsic aspect ratio. (https://github.com/mozdevs/cssremedy/issues/14)
*/

img,
video {
  max-width: 100%;
  height: auto;
}

/* Make elements with the HTML hidden attribute stay hidden by default */
[hidden] {
  display: none;
}