/* * ``: M3 Expressive's top app bars (AppBarTokens.kt, AppBarSmallTokens.kt, * AppBarMediumFlexibleTokens.kt, AppBarLargeFlexibleTokens.kt, androidx Compose Material 3, * Apache-2.0; docs/reference/m3/components-navigation-selection-inputs.md § Top App Bar). * * [data-md-app-bar] the bar; data-md-variant, data-md-sticky, data-md-subtitled, * data-md-scrolled/data-md-collapsed (resources/js/app-bar.js) * [data-md-app-bar-row] 64px, sticky at the top of the bar * [data-md-app-bar-leading] the `navigation` slot * [data-md-app-bar-headline] [data-md-app-bar-title], [data-md-app-bar-subtitle] * [data-md-app-bar-search] the `search` variant's slot * [data-md-app-bar-trailing] [data-md-app-bar-action], [data-md-app-bar-overflow] * [data-md-app-bar-expanded] medium/large's big title, under the row * * small 64px, title-large title (label-medium subtitle), 4px from the edges, the title 16px * from the start or straight after the navigation icon * center the same, the title centred — a three-column grid, so it shrinks against whatever is * beside it rather than ellipsising underneath it: a fixed inset fit exactly one * of M3's two trailing buttons * medium 112px (136px with a subtitle): the 64px row of icons over a headline-medium title * large 120px (152px with a subtitle): a display-small title * search the row holds a search bar, full width to 312px and then half of what is left * * The container is the surface, and surface-container once content scrolls under it. A medium or * large bar collapses into the small one without script moving anything: the bar is sticky at a * negative top, so it scrolls up until only 64px of it remain, while its row of icons is sticky at * 0 inside it and stays put — the big title scrolls away under the row. Script only says when that * has happened (resources/js/app-bar.js), so the small title can fade in and the colour change. * * Trailing actions given as a list collapse into an overflow menu below `medium` and come back * from it, by media query alone (the site's "trailing actions collapse into an overflow menu at * smaller breakpoints" and "become visible again at larger sizes", read together with "up to two * icon buttons" and, for a wider window, "up to four trailing icons"): both forms of every action * are in the page, and each width hides the one it does not use, so nothing flashes and no script * counts. */ @layer material.reset, material.tokens, material.base, material.layout, material.components, material.text, material.visibility; @import './button.css'; @import './menu.css'; @import './menu-item.css'; @layer material.components { [data-md-app-bar] { --app-bar-row: 64px; --app-bar-height: var(--app-bar-row); z-index: 20; display: block; min-height: var(--app-bar-height); padding-top: var(--material-safe-top, env(safe-area-inset-top)); background-color: var(--md-sys-color-surface); color: var(--md-sys-color-on-surface); transition-property: background-color; transition-duration: var(--md-sys-motion-effects-default-duration); transition-timing-function: var(--md-sys-motion-effects-default); } [data-md-app-bar][data-md-variant='medium'] { --app-bar-height: 112px; } [data-md-app-bar][data-md-variant='medium'][data-md-subtitled] { --app-bar-height: 136px; } [data-md-app-bar][data-md-variant='large'] { --app-bar-height: 120px; } [data-md-app-bar][data-md-variant='large'][data-md-subtitled] { --app-bar-height: 152px; } [data-md-app-bar][data-md-sticky] { position: sticky; top: 0; } /* `--app-bar-measured` is the bar's real height (a title can wrap), set by app-bar.js. */ [data-md-app-bar][data-md-sticky]:is([data-md-variant='medium'], [data-md-variant='large']) { top: calc(var(--app-bar-row) - var(--app-bar-measured, var(--app-bar-height))); } [data-md-app-bar][data-md-scrolled] { background-color: var(--md-sys-color-surface-container); } [data-md-app-bar-row] { position: sticky; top: 0; z-index: 1; display: flex; align-items: center; gap: 0; min-height: var(--app-bar-row); padding-inline: var(--md-sys-measurement-space50); background-color: inherit; } [data-md-app-bar-leading], [data-md-app-bar-trailing] { display: flex; flex: none; align-items: center; color: var(--md-sys-color-on-surface-variant); } [data-md-app-bar-leading] { color: var(--md-sys-color-on-surface); } [data-md-app-bar-trailing] { margin-inline-start: auto; } /* `actions` as a list: every action is both an icon button and a menu item, and the width of the window says which one is drawn — up to two trailing icon buttons below `medium` and four from it, an overflow button counted among them. The wrappers stay out of the row's layout until a width hides them. */ [data-md-app-bar-action], [data-md-app-bar-overflow] { display: contents; } @media (width < 600px) { [data-md-app-bar-action][data-md-overflows-compact], [data-md-app-bar-overflow='medium'] { display: none; } } @media (width >= 600px) { [data-md-app-bar-overflow='compact'] { display: none; } } [data-md-app-bar-headline] { display: flex; min-width: 0; flex: 1 1 0%; flex-direction: column; justify-content: center; padding-inline: 12px; } [data-md-app-bar-row]:has([data-md-app-bar-leading]) [data-md-app-bar-headline] { padding-inline-start: var(--md-sys-measurement-space50); } [data-md-app-bar-title] { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; font: var(--md-sys-typescale-title-lg); letter-spacing: var(--md-sys-typescale-title-lg-tracking); } [data-md-app-bar-subtitle] { overflow: hidden; color: var(--md-sys-color-on-surface-variant); text-overflow: ellipsis; white-space: nowrap; font: var(--md-sys-typescale-label-md); letter-spacing: var(--md-sys-typescale-label-md-tracking); } /* Centred: a three-column row — leading, headline, trailing — so the headline is centred in the window and shrinks against whatever is actually beside it. M3 allows two trailing icon buttons, which a fixed inset for one would have let a long title ellipsise underneath. */ [data-md-app-bar][data-md-variant='center'] [data-md-app-bar-row] { display: grid; grid-template-columns: 1fr auto 1fr; } [data-md-app-bar][data-md-variant='center'] [data-md-app-bar-leading] { grid-column: 1; justify-self: start; } [data-md-app-bar][data-md-variant='center'] [data-md-app-bar-headline] { grid-column: 2; min-width: 0; align-items: center; justify-self: center; padding-inline: 12px; text-align: center; } [data-md-app-bar][data-md-variant='center'] [data-md-app-bar-trailing] { grid-column: 3; justify-self: end; margin-inline-start: 0; } /* The search bar fills the space between the leading and trailing elements until it is 312dp wide, and then grows into only half of what is left. The percentage is of the row rather than of that space, which CSS cannot name without measuring it; below 312px the cap never binds, so a phone still gets the whole row. */ [data-md-app-bar-search] { min-width: 0; max-width: calc(312px + (100% - 312px) / 2); flex: 1 1 0%; margin-inline: auto; padding-inline: var(--md-sys-measurement-space50); } /* Medium and large: the row's title is the collapsed one, shown once the big one has gone. */ [data-md-app-bar]:is([data-md-variant='medium'], [data-md-variant='large']) [data-md-app-bar-row] [data-md-app-bar-headline] { opacity: 0; transition-property: opacity; transition-duration: var(--md-sys-motion-effects-fast-duration); transition-timing-function: var(--md-sys-motion-effects-fast); } [data-md-app-bar][data-md-collapsed] [data-md-app-bar-row] [data-md-app-bar-headline] { opacity: 1; } /* Heights from the tokens: the title (and subtitle) lines and the space under them fill what the row leaves — 36 + 12px medium, 36 + 20 + 16px with a subtitle; 44 + 12px large, 44 + 24 + 20px. */ [data-md-app-bar-expanded] { display: flex; min-height: calc(var(--app-bar-height) - var(--app-bar-row)); flex-direction: column; justify-content: flex-end; padding-inline: var(--md-sys-measurement-space200); padding-bottom: 12px; } [data-md-app-bar][data-md-subtitled] [data-md-app-bar-expanded] { padding-bottom: var(--md-sys-measurement-space200); } [data-md-app-bar][data-md-variant='large'][data-md-subtitled] [data-md-app-bar-expanded] { padding-bottom: 20px; } [data-md-app-bar-expanded] [data-md-app-bar-title] { white-space: normal; font: var(--md-sys-typescale-headline-md); letter-spacing: var(--md-sys-typescale-headline-md-tracking); } [data-md-app-bar-expanded] [data-md-app-bar-subtitle] { font: var(--md-sys-typescale-label-lg); letter-spacing: var(--md-sys-typescale-label-lg-tracking); } [data-md-app-bar][data-md-variant='large'] [data-md-app-bar-expanded] [data-md-app-bar-title] { font: var(--md-sys-typescale-display-sm); letter-spacing: var(--md-sys-typescale-display-sm-tracking); } [data-md-app-bar][data-md-variant='large'] [data-md-app-bar-expanded] [data-md-app-bar-subtitle] { font: var(--md-sys-typescale-title-md); letter-spacing: var(--md-sys-typescale-title-md-tracking); } }