https://github.com/mozilla-b2g/gaia/pull/18784 precompiled by provecss

headers.css

/* -----------------------------------------------------------------
  HEADERS: layout
  This is our base CSS file.
  Should not be defined here form factor or skin 
  dependent styles.
----------------------------------------------------------------- */

section[role="region"] > header:first-child {
  position: relative;
  z-index: 10;
  padding: 0;
  height: 5rem;
  border: none;
}

section[role="region"] > header:first-child h1 {
  font-size: 2.5rem;
  line-height: 5rem;
  text-align: left;
  white-space: nowrap;
  text-overflow: ellipsis;
  display: block;
  overflow: hidden;
  margin: 0;
  padding: 0 1rem 0 3rem;
  height: 100%;
  font-weight: lighter;
  font-style: italic;
}

section[role="region"] > header:first-child h1 em {
  font-weight: 400;
  font-size: 1.5rem;
  line-height: 1em;
  font-style: normal;
}

/* Forms in header are only used in email app. 
   Incorrect UI style.
   Sould be removed after landing bug 1001298 
*/

section[role="region"] > header:first-child form {
  display: block;
  overflow: hidden;
  position: relative;
  padding: 1rem 1rem 0 0.5rem;
  margin-left: 3.5rem;
}

section[role="region"] > header:first-child input[type="text"] {
  width: 100%;
  height: 3rem;
  -moz-box-sizing: border-box;
  padding: 0 0.8rem;
  border: solid 0.1rem #9d4123;
  border-top-color: #a6501e;
  border-radius: 0;
  background: #fff;
  font-size: 1.5rem;
  line-height: 3em;
  box-shadow: none;
}

section[role="region"] > header:first-child form button[type="reset"] {
  font-size: 0;
  overflow: hidden;
  position: absolute;
  right: 1rem;
  top: 1rem;
  bottom: 0;
  width: 3rem;
  height: auto;
  margin: 0;
  display: none;
  border: none;
  background: url(images/icons/clear.png) no-repeat center center / 1.7rem auto;
}

section[role="region"] > header:first-child input[type="text"]:valid + button[type="reset"] {
  display: block;
}

section[role="region"] > header:first-child menu {
  height: 100%;
  float: right;
  padding: 0;
  margin: 0;
}

/* ----------------------------------
  Buttons
---------------------------------- */

section[role="region"] > header:first-child a,
section[role="region"] > header:first-child button {
  -moz-box-sizing: border-box;
  position: absolute;
  overflow: visible;
  float: left;
  width: 5rem;
  height: 5rem;
  border: none;
  background: none;
  padding: 0;
  overflow: hidden;
  font-weight: 400;
  font-size: 1.5rem;
  line-height: 1.1em;
  border-radius: 0;
  text-decoration: none;
  margin: 0 -5rem 0 0;
  border-radius: 0;
}

section[role="region"] > header:first-child button:after,
section[role="region"] > header:first-child a:after {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  z-index: -1;
  width: 2.6rem;
  height: 5rem;
}

section[role="region"] > header:first-child menu a,
section[role="region"] > header:first-child menu button,
section[role="region"] > header:first-child[is] a,
section[role="region"] > header:first-child[is] button {
  position: relative;
  float: left;
  width: auto;
  min-width: 5rem;
  padding: 0 1rem;
  margin: 0;
  line-height: 5rem;
  text-align: center;
  text-shadow: none;
  z-index: 5;
  font-style: italic;
}

section[role="region"] > header:first-child menu a:after,
section[role="region"] > header:first-child menu button:after,
section[role="region"] > header:first-child[is] a:after,
section[role="region"] > header:first-child[is] button:after {
  width: 100%;
}

/* Pressed state */

section[role="region"] > header:first-child a:focus {
  outline: none;
}

section[role="region"] > header:first-child button::-moz-focus-inner {
  outline: none;
  border: none;
  margin-top: -0.2rem;
  /* To fix line-height bug (697451) */
  padding: 0;
}

/* Disabled state */

section[role="region"] > header:first-child a[aria-disabled="true"],
section[role="region"] > header:first-child button[disabled] {
  opacity: 0.3;
  pointer-events: none;
}

/* Icon definitions */

section[role="region"] > header:first-child .icon {
  display: block;
  width: 3rem;
  height: 5rem;
  background: transparent no-repeat -0.2rem center / 3rem auto;
  font-size: 0;
}

section[role="region"] > header:first-child menu .icon,
[is="gaia-header"] [icon] {
  background-position: center;
}

[is="gaia-header"] [icon] {
  font-size: 0;
}

[is="gaia-header"] [icon]:before {
  position: absolute;
  content: "";
  width: 3rem;
  height: 3rem;
  background: transparent no-repeat center / 3rem auto;
  top: 1rem;
  left: 1rem;
}

section[role="region"] > header:first-child .icon.icon-add,
[is="gaia-header"] [icon="add"]:before {
  background-image: url(images/icons/add.png);
}

section[role="region"] > header:first-child .icon.icon-compose,
[is="gaia-header"] [icon="compose"]:before {
  background-image: url(images/icons/compose.png);
}

section[role="region"] > header:first-child .icon.icon-edit,
[is="gaia-header"] [icon="edit"]:before {
  background-image: url(images/icons/edit.png);
}

section[role="region"] > header:first-child .icon.icon-send,
[is="gaia-header"] [icon="send"]:before {
  background-image: url(images/icons/send.png);
}

section[role="region"] > header:first-child .icon.icon-close,
[is="gaia-header"] [icon="close"]:before {
  background-image: url(images/icons/close.svg);
}

section[role="region"] > header:first-child .icon.icon-back,
[is="gaia-header"] [icon="back"]:before {
  background-image: url(images/icons/back.svg);
}

section[role="region"] > header:first-child .icon.icon-menu,
[is="gaia-header"] [icon="menu"]:before {
  background-image: url(images/icons/menu.svg);
}

section[role="region"] > header:first-child .icon.icon-user,
[is="gaia-header"] [icon="user"]:before {
  background-image: url(images/icons/user.png);
}

section[role="region"] > header:first-child .icon.icon-up,
[is="gaia-header"] [icon="up"]:before {
  background-image: url(images/icons/up.png);
}

section[role="region"] > header:first-child .icon.icon-down,
[is="gaia-header"] [icon="down"]:before {
  background-image: url(images/icons/down.png);
}

section[role="region"] > header:first-child .icon.icon-options,
[is="gaia-header"] [icon="options"]:before {
  background-image: url(images/icons/options.png);
}

/* ----------------------------------
  Subheader
---------------------------------- */

section[role="region"] > header {
  z-index: 0;
  height: auto;
}

section[role="region"] header h2 {
  margin: 0;
  padding: 0.8rem 3rem;
  font-weight: 400;
  font-size: 1.5rem;
  line-height: 1.8rem;
}

/* ----------------------------------
  right-to-left
---------------------------------- */

html[dir="rtl"] section[role="region"] > header:first-child h1 {
  text-align: right;
  padding: 0 3rem 0 1rem;
}

html[dir="rtl"] section[role="region"] > header:first-child form {
  padding: 1rem .5rem 0 1rem;
  margin-right: 3.5rem;
  margin-left: 0;
}

html[dir="rtl"] section[role="region"] > header:first-child form button[type="reset"] {
  left: 1rem;
  right: inherit;
}

html[dir="rtl"] section[role="region"] > header:first-child menu {
  float: left;
}

html[dir="rtl"] section[role="region"] > header:first-child button,
html[dir="rtl"] section[role="region"] > header:first-child a {
  float: right;
  margin: 0 0 0 -5rem;
}

html[dir="rtl"] section[role="region"] > header:first-child menu a,
html[dir="rtl"] section[role="region"] > header:first-child menu button,
html[dir="rtl"] section[role="region"] > header:first-child[is] a,
html[dir="rtl"] section[role="region"] > header:first-child[is] button {
  margin: 0;
}

html[dir="rtl"] section[role="region"] > header:first-child button:after,
html[dir="rtl"] section[role="region"] > header:first-child a:after {
  right: 0;
}

html[dir="rtl"] section[role="region"] > header:first-child .icon {
  background-position: 0.2rem center;
}

html[dir="rtl"] section[role="region"] > header:first-child menu .icon,
html[dir="rtl"] [is="gaia-header"] [icon] {
  background-position: center;
}

html[dir="rtl"] section[role="region"] > header:first-child .icon.icon-back {
  background-position: -0.2rem center;
  transform: rotate(180deg);
}

/* -----------------------------------------------------------------
  HEADER SKIN: default
  Default values if we are not overriding them using 
  class="skin-*"
----------------------------------------------------------------- */

section[role="region"] > header:first-child {
  color: #fff;
  background-color: #f97c17;
}

section[role="region"] > header:first-child h1 {
  color: #fff;
}

section[role="region"] > header:first-child a,
section[role="region"] > header:first-child button {
  color: rgba(0,0,0,0.6);
}

section[role="region"] > header:first-child a:active:after,
section[role="region"] > header:first-child button:active:after,
section[role="region"] > header:first-child a:hover:after,
section[role="region"] > header:first-child button:hover:after {
  background-color: rgba(0,0,0,0.07);
}

section[role="region"] header h2 {
  color: #424242;
  border-bottom: solid 0.1rem #e6e6e6;
}

/* -----------------------------------------------------------------
  HEADER SKIN: comms
  .skin-comms will override default values
----------------------------------------------------------------- */

.skin-comms section[role="region"] > header:first-child,
section[role="region"].skin-comms > header:first-child {
  background-color: #33cccc;
}

.skin-comms section[role="region"] > header:first-child a,
.skin-comms section[role="region"] > header:first-child button,
section[role="region"].skin-comms > header:first-child a,
section[role="region"].skin-comms > header:first-child button {
  color: rgba(0,0,0,0.5);
}

.skin-comms section[role="region"] > header:first-child a:active:after,
.skin-comms section[role="region"] > header:first-child button:active:after,
.skin-comms section[role="region"] > header:first-child a:hover:after,
.skin-comms section[role="region"] > header:first-child button:hover:after,
section[role="region"].skin-comms > header:first-child a:active:after,
section[role="region"].skin-comms > header:first-child button:active:after,
section[role="region"].skin-comms > header:first-child a:hover:after,
section[role="region"].skin-comms > header:first-child button:hover:after {
  background-color: rgba(0,0,0,0.1);
}

/* -----------------------------------------------------------------
  HEADER SKIN: dark
  .skin-dark will override default values
----------------------------------------------------------------- */

section[role="region"].skin-dark > header:first-child,
.skin-dark > section[role="region"] > header:first-child {
  background-color: #242d33;
}

.skin-dark section[role="region"] > header:first-child a,
.skin-dark section[role="region"] > header:first-child button,
section[role="region"].skin-dark > header:first-child a,
section[role="region"].skin-dark > header:first-child button {
  color: #00aac5;
}

.skin-dark section[role="region"] > header:first-child a:active:after,
.skin-dark section[role="region"] > header:first-child button:active:after,
.skin-dark section[role="region"] > header:first-child a:hover:after,
.skin-dark section[role="region"] > header:first-child button:hover:after,
section[role="region"].skin-dark > header:first-child a:active:after,
section[role="region"].skin-dark > header:first-child button:active:after,
section[role="region"].skin-dark > header:first-child a:hover:after,
section[role="region"].skin-dark > header:first-child button:hover:after {
  background-color: rgba(0,0,0,0.4);
}

section[role="region"].skin-dark header h2,
.skin-dark > section[role="region"] header h2 {
  background-color: #2c353b;
  color: #fff;
  border: none;
}

/* -----------------------------------------------------------------
  HEADER SKIN: organic
  .skin-organic will override default values
----------------------------------------------------------------- */

section[role="region"].skin-organic > header:first-child,
.skin-organic section[role="region"] > header:first-child {
  background-color: #f4f4f4;
}

section[role="region"].skin-organic > header:first-child h1,
.skin-organic section[role="region"] > header:first-child h1 {
  color: #868692;
}

section[role="region"].skin-organic > header:first-child a,
.skin-organic section[role="region"] > header:first-child a,
section[role="region"].skin-organic > header:first-child button,
.skin-organic section[role="region"] > header:first-child button {
  color: #00aac5;
}

section[role="region"].skin-organic > header:first-child .icon.icon-back,
.skin-organic section[role="region"] > header:first-child .icon.icon-back,
[is="gaia-header"][skin="organic"] [icon="back"]:before {
  background-image: url(images/icons/organic/back.svg);
}

section[role="region"].skin-organic > header:first-child .icon.icon-close,
.skin-organic section[role="region"] > header:first-child .icon.icon-close,
[is="gaia-header"][skin="organic"] [icon="close"]:before {
  background-image: url(images/icons/organic/close.svg);
}

section[role="region"].skin-organic > header:first-child .icon.icon-add,
.skin-organic section[role="region"] > header:first-child .icon.icon-add,
[is="gaia-header"][skin="organic"] [icon="add"]:before {
  background-image: url(images/icons/organic/add.png);
}

section[role="region"].skin-organic > header:first-child .icon.icon-edit,
.skin-organic section[role="region"] > header:first-child .icon.icon-edit,
[is="gaia-header"][skin="organic"] [icon="edit"]:before {
  background-image: url(images/icons/organic/edit.png);
}

section[role="region"].skin-organic header h2,
.skin-organic section[role="region"] header h2 {
  background-color: #e7e7e7;
  color: #4d4d4d;
  border: none;
}