SafariFox: a Safari style for Firefox.

userChrome.css

/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/*This style will make your browser similar to Safari.  Currently tested on MacOS Sierra and Linux on Nightly*/

/*tabs on bottom*/
#TabsToolbar {
  -moz-box-ordinal-group: 2 !important;
}
#nav-bar{
  border-top-width: 0px !important;
  -moz-box-ordinal-group: 0 !important;
}
#TabsToolbar .tabbrowser-tabs {
  height: 16px !important;
  border-bottom: 1px solid #B1B1B1 !important;
}

/*tab line hidden*/
.tab-line {
  display: none !important;
}

/*Bookmarks Bar fix*/
#PersonalToolbar {
  -moz-box-ordinal-group: 2;
  background: rgb(230, 230, 230) !important;
  border-bottom: 1px solid #B1B1B1 !important;
}

/*Remove extra tab bar space*/
#TabsToolbar {
  padding-inline-start: 0px !important;
  margin-bottom: none !important;
}

.titlebar-placeholder {
  display: none;
}

/*full-width tabs*/
#TabsToolbar .tabbrowser-tab[fadein]:not([pinned]) {
  flex-grow: 1 !important;
  min-width: 11em !important;
  max-width: 100% !important;
}

#TabsToolbar {
  box-shadow: inset 0px 1px 0px 0px rgb(172,170,172), inset 0px -1px 0px 0px rgb(172,170,172) !important;
  margin-bottom: 0px !important;
  margin-left: 0px !important;
  margin-right: -1px !important;
  background: linear-gradient(to bottom, rgb(212,210,212),rgb(207,205,207)) !important;
}

/*Hide and show close tab button*/
#TabsToolbar .tab-close-button {
  -moz-box-ordinal-group: 1 !important;
  margin-left: -5.5px !important;
  border-radius: 2px !important;
  transition: opacity 200ms !important;
    /* small x */
  list-style-image: url('data:image/svg+xml;utf8,\<svg xmlns="http://www.w3.org/2000/svg" width="16" height="16">\<line x1="4.5" y1="4.5" x2="11.5" y2="11.5" stroke="rgb(84,82,84)" stroke-width="1"/>\<line x1="4.5" y1="11.5" x2="11.5" y2="4.5" stroke="rgb(84,82,84)" stroke-width="1"/>\</svg>') !important;
}

@media (max-resolution: 1.9dppx) {
  #TabsToolbar .tab-close-button {
    list-style-image: url('data:image/svg+xml;utf8,\<svg xmlns="http://www.w3.org/2000/svg" width="16" height="16">\<line x1="4.5" y1="4.5" x2="11.5" y2="11.5" stroke="rgb(84,82,84)" stroke-width="1.5"/>\<line x1="4.5" y1="11.5" x2="11.5" y2="4.5" stroke="rgb(84,82,84)" stroke-width="1.5"/>\</svg>') !important;
  }
}

#TabsToolbar tab:not(:hover) .tab-close-button {
  opacity: 0 !important;
}

#TabsToolbar tab:hover .tab-close-button {
  opacity: 1 !important;
}

#TabsToolbar tab .close-icon {
  -moz-image-region: unset !important;
}

#TabsToolbar tab .close-icon:hover {
  -moz-image-region: unset !important;
  background-color: rgba(0,0,0,0.1) !important;
  background-clip: padding-box !important;
}

#TabsToolbar tab .close-icon:hover:active {
  background-color: rgba(0,0,0,0.15) !important;
}

/*Heights*/

/*
 * Change the last padding value to 5px for Windows, Linux, or if 
 * you're using the titlebar
 */
#nav-bar {
  height: 38px !important;
  padding: 0px 5px 0px 0px !important;
}
#tabbrowser-tabs {
  margin-left: 0px !important;
  height: 18px !important;
}
#TabsToolbar .tab-content > * {
  margin-top: 0px !important;
  margin-bottom: 0px !important;
}

/*Colors*/
#nav-bar {
  background: linear-gradient(rgb(250, 250, 250), rgb(240, 240, 240)) !important;
  border-bottom: 1px solid #B1B1B1 !important;
}
#TabsToolbar {
  background: #DBDBDB !important;
}
.tab-background[selected="true"] {
    background-attachment: none !important;
    background-color: rgb(240, 240, 240) !important;
    background-image: none !important;
}
/*
#urlbar {
  background: #FAFAFA !important;
  border: 1px solid rgba(0,0,0,0.5);
}
*/
/* NUEVO */
#urlbar {
    border: none !important;
    box-shadow: none !important;
    -moz-transition: all 0.3s ease 0s !important;
    border-radius: 2em !important;
    background: none !important;
}

#urlbar[focused="true"] {
    border: solid 1px #ccc !important;
    box-shadow: 0 0 4px 4px #EAEAEAEA !important;
    background: white !important;
}

#urlbar .urlbar-input-box {
    text-align: center !important;
}
.urlbar-input-box > .urlbar-input::placeholder {
  opacity: 0 !important;
}
/*Hide Favicons, center text*/
.tabbrowser-tabs .tab-icon-image {
  display: none !important;
}
.tabbrowser-tab[pinned]:not([busy="true"]) .tab-icon-image {
  display: block !important;
}
.tab-label {
  -moz-box-flex: 1 !important;
  text-align: center !important;
}

/*position window controls*/
#titlebar-buttonbox-container {
  margin-left: 5px !important;
  margin-top: 10.5px !important;
}

/* remove this weird extra separator mozilla tacks on before the page content */
#navigator-toolbox::after {
  display: none !important;
}