The following code is used by Weaver Xtreme Version 4.0 to support Gutenberg block styling in both the front-end and for the visual editor in the back end. This code is subject to change as both Weaver Xtreme and Gutenberg evolve. See the latest version of Weaver Xtreme for the latest version of this file.

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gutenberg-base-editor-style.css

/*---------------------------------------------------------------------------------
 * Weaver Xtreme Theme - Version 4.0
 * First created April 2018
 * License: GNU General Public License v3 or later
 * License URI: //www.gnu.org/licenses/gpl-3.0.html
 * Copyright 2018, Bruce E. Wampler
 *
 * gutenberg-base-editor-style.css - Version 3.9.3
 *
 * Provides base styling for Gutenberg Editor
 * Enqueue this style sheet in theme's enqueue_block_editor_assets action.
 *
 * This does not style the font-end view, but just the editor.
 * Front-end base styling for Gutenberg blocks provided by gutenberg-blocks.css
 *
 * Note that this file will loaded via the enqueue_block_editor_assets action, which loads
 * for the editor only
 *
 * --------------------------------------------------------------------------------- */

/*
 * Theme Styles found in Theme main style file
 *
 * Rather than loading the entire theme style sheet for the editor, the theme specific
 * styles relevant to page post content should be duplicated in these styles. Here, they
 * are mixed in with the .wp-block styles, but prefixed by .mce-content-body.
 *
 */

/* ====== Widths ====== */

/*
 * Front-end default width set by theme. This comes close to making the editor match the theme's 1100px
 * width fairly closely on a wide desktop view.
 *
 * This width does not account for sidebars, which might make the actual width on the front-end display smaller.
 */


.edit-post-visual-editor .editor-post-title,
.edit-post-visual-editor .editor-block-list__block {
	max-width:			1100px;
}

.edit-post-visual-editor .editor-block-list__block[data-align="wide"] {
	max-width: 			1300px;
}

.edit-post-layout {
	background-color: 	#FFF;
	box-sizing: 		border-box;
}

.edit-post-layout .editor-post-title textarea {		/* tweak the title text box and textarea */
	background-color: 	transparent;		/* need to set to inherit so styling can use .editor-post-title only */
	color: 				inherit;
	font:				inherit;
	padding-bottom:		0px;
	margin-bottom:		0px;
}

.edit-post-layout .editor-post-title {
	color:				inherit;
	background-color: 	transparent;
	font-weight:		bold;
	margin-bottom:		.5em;
	padding-bottom: 	0;
	padding-top: 		0;
	position: 			relative;
}


/* ======= blockquote ====== */

.mce-content-body blockquote {
	background:		rgba(128, 128, 128, 0.1);
	border-left:	4px solid rgba(128, 128, 128, 0.4) !important;
	margin:			1.5em auto	!important;
	overflow:		auto;
	padding:		0.8em 1.5em 1em 1.2em;
	width: 			90%;
}

.mce-content-body blockquote cite {
	font-style:		normal;
	font-weight:	bold;
}

.mce-content-body blockquote p {
	font-style:		italic;
	font-size:		1em;
	margin-bottom:	0;
}

.mce-content-body em,
.mce-content-body i {
	font-style:		italic;
}

.mce-content-body cite {			/* cite is supposed to be used only in a quote or blockquote */
	border-width:	0;
	display:		block;
	margin-left:	3em;
	margin-top:		.5em;
}

.mce-content-body blockquote em,
.mce-content-body blockquote i {
	font-style: 	italic;
}



/* ====== Cover Images ====== */
/*
 * Following styling assumes the theme treats block-cover-image as a fullwidth parallax image.
 * They won't display as full width in the editor, but will extend to margins.
 *
 */

.editor-block-list__block .wp-block-cover-image {
	height: 			50vh;
	margin-left:		auto;
	margin-right:		auto;
	min-height: 		400px;
	width:				100%;
}

.editor-block-list__block .wp-block-cover-image.alignfull {		/* This makes a full area image */
		left: 			0;
		margin-left: 	auto;
		margin-right:	auto;
		width: 			100%;
	}


/* ======= Heading elements - <h1>-<h6> ====== */
.wp-block-heading h1,
.wp-block-heading h2,
.wp-block-heading h3,
.wp-block-heading h4,
.wp-block-heading h5,
.wp-block-heading h6,
.mce-content-body h1,
.mce-content-body h2,
.mce-content-body h3,
.mce-content-body h4,
.mce-content-body h5,
.mce-content-body h6 {
	clear:				both;
	color:				inherit;
	font-family:		inherit;
	clear: 				both;
	margin:				0;
}

.wp-block-heading h1,
.wp-block-heading h2,
.mce-content-body h1,
.mce-content-body h2 {
	margin-top:			0.5em;
}

.wp-block-heading h1,
.mce-content-body h1 {
	font-size:			262.5%;		/* these sizes derived from theme */
	line-height: 		1;
	margin-bottom:		0.6em;
}

.wp-block-heading h2,
.mce-content-body h2 {
	font-size:			200%;
	line-height: 		1.1;
	margin-bottom:		0.7em;
}

.wp-block-heading h3,
.mce-content-body h3 {
	font-size:			162.5%;
	line-height: 		1.1;
	margin-bottom:		0.9em;
}

.wp-block-heading h4,
.mce-content-body h4 {
	font-size:			125%;
	line-height: 		1.1;
	margin-bottom:		1.0em;
}

.wp-block-heading h5,
.mce-content-body h5 {
	font-size:			112.5%;
	line-height: 		1.1;
	margin-bottom:		1.0em;
}

.wp-block-heading h6,
.mce-content-body h6 {
	font-size:			100%;
	line-height: 		1.1;
	margin-bottom:		1.0em;
}


/* ====== Images ====== */
/**
 * We will do minimal styling on images.
 * This will allow Gutenberg to style its images, and the theme to style non-Gutenberg images.
 *
 */

.mce-content-body img {
	max-width: 			100%;
}
.mce-content-body img[class*="wp-image-"] {
	height: 			auto;
	max-width: 			100%;
}

.mce-content-body img.size-full {
	max-width: 			100% !important;
	width: 				auto; /* Prevent stretching of full-size images in IE8 */
}

.mce-content-body img.wp-smiley {
	border: 			none;
	margin-bottom: 		0;
	margin-top: 		0;
	padding: 			0;
}
.mce-content-body p img,
.wp-caption {
	margin-top: 		0.4em;
}

.mce-content-body img {
	background-color: 	transparent;
	margin-bottom: 		1em;
	padding: 			0;			/* image border width */
}

.wp-caption, img {
	background-color: 	transparent;
	border:				none;
	height: 			auto;
	margin: 			0;
	margin-bottom: 		1em;
	max-width: 			100%;
	padding: 			0;			/* image border width */
	text-align: 		center;
}
.wp-caption {
	margin:				10px 20px 10px 10px;
	padding: 			8px 3px 0px 3px;
}

.mce-content-body img.alignleft,
.mce-content-body img.alignright,
.mce-content-body img.aligncenter {
	margin-bottom: 		1.625em;
}



/* ====== Lists ====== */

.mce-content-body dl,
.mce-content-body dt,
.mce-content-body dd,
.mce-content-body ol,
.mce-content-body ul,
.mce-content-body li {
	margin:				0;
	padding:			0;
	word-wrap:			break-word;
}

.mce-content-body p {
	margin: 			0 0 1em 0;
}

.mce-content-body .atwk-slide .post ol,		/* also support Weaver Show Slides */
.mce-content-body .atwk-slide .post ul,
.mce-content-body .atw-post ol,
.mce-content-body .atw-post ul,
.mce-content-body ol,
.mce-content-body ul {
	list-style-position:    outside;
}

.mce-content-body .widget ol,
.mce-content-body .widget ul {
	list-style-position:    outside;
	margin-left:			1.0em;
}

.mce-content-body ol {
	list-style-type:	decimal;
}

.mce-content-body ol ol {
	list-style:			upper-alpha;
}

.mce-content-body ol ol ol {
	list-style:			lower-roman;
}

.mce-content-body ol ol ol ol {
	list-style:			lower-alpha;
}

.mce-content-body dl {
	margin:				0 1.5em;
}

.mce-content-body dt {
	font-weight:		bold;
}

.mce-content-body dd {
	margin-left:		1.5em;
	margin-bottom:      1.5em;
}

.mce-content-body ul {
	list-style:			disc outside none;
}

/* other elements */
.mce-content-body abbr,
.mce-content-body acronym,
.mce-content-body dfn {
	border-bottom: 		1px dotted #666;
}
.mce-content-body address {
	display: 			block;
	font-style:			italic;
	margin: 			0 0 1.625em;
}
.mce-content-body big {
	font-size: 			130%;
}

.mce-content-body code,
.mce-content-body kbd,
.mce-content-body tt,
.mce-content-body var {
	color: 				inherit !important;
	background:			none !important;
	font-family:		'Inconsolata', monospace;
	font-size:			1em;
}

.mce-content-body del {
	color:				#222;
}

.mce-content-body pre {
	box-shadow:				0 1px 0 #ffffff, inset 0 1px 1px rgba(0, 0, 0, 0.2);
	box-sizing:				border-box;
	background:				rgba(128, 128, 128, 0.1);
	border:					1px solid #aaaaaa;
	border-bottom-color:    #cccccc;
	border-radius:			2px;
	font-family:			'Inconsolata', monospace;
	font-size:				.8em;
	height:					auto;
	margin:					0;
	margin-bottom:			1.5em;
	outline:				none;
	overflow:				auto;
	padding:				6px 10px;
	vertical-align:			middle;
	width:					100%;
	word-wrap:				break-word;
	white-space:			pre-wrap;
}


.mce-content-body q {
	font-style: 		italic;
}

.mce-content-body ins {
	background: 		#ccc;
	color:				#222;
}

.mce-content-body strong {
	font-weight: 		bold;
}

.mce-content-body sup,
.mce-content-body sub {
	font-size: 			90%;
	height: 			0;
	line-height: 		1;
	position: 			relative;
	vertical-align: 	baseline;
}

.mce-content-body sup {
	bottom: 			1ex;
}

.mce-content-body sub {
	top: 				.5ex;
}

.mce-content-body var {
	font-style:			italic;
}

.editor-block-list__block:not(.is-multi-selected) .wp-block-paragraph {
	background:			transparent;
}


.mce-content-body label {
	font-family: 		inherit;
	font-size: 			1em;	/* 133% * 12 */
}



/* tables */
.mce-content-body table, .mce-content-body caption,
.mce-content-body tbody, .mce-content-body tfoot,
.mce-content-body thead, .mce-content-body tr,
.mce-content-body th, .mce-content-body td {
	word-wrap:			break-word;
}

/* tables */
.mce-content-body table,
.mce-content-body th,
.mce-content-body td {
	border: 			1px solid #d1d1d1;
}

.mce-content-body table {
	border-collapse: 	separate;
	border-spacing: 	0;
	border-width: 		1px 0 0 1px;
	margin: 			0 0 1.75em;
	table-layout: 		fixed;
	/* Prevents HTML tables from becoming too wide */
	width: 				100%;
}


.mce-content-body th,
.mce-content-body td {
	font-weight: 		normal;
	padding: 			0.4375em;
	text-align: 		left;
}

.mce-content-body th {
	border-width: 		0 1px 1px 0;
	font-weight: 		bold;
	padding:			4px 4px;
	text-align:			left;
}

.mce-content-body td {
	border-width: 		0 1px 1px 0;
	margin:				0;
	padding:			4px 4px;
}


/* hr +*/
.mce-content-body hr {
	background-color:	#ccc;
	border:				none;
	box-sizing:			content-box;
	height:				4px;
	margin:				1.0em auto;
	max-width:			90%;
	width: 				90%;
}


/* Text elements */
.mce-content-body p, .mce-content-body ul, .mce-content-body ol, .mce-content-body dl {
	font-weight: 		300;
}
.mce-content-body p {
	margin-bottom: 		1.5em;
}

.mce-content-body input[type=text],
.mce-content-body textarea {
	background: 		inherit;
	box-shadow: 		inset 0 1px 1px rgba(0,0,0,0.1);
	border: 			1px solid #ddd;
	color: 				#888;
}
.mce-content-body input[type=text]:focus,
.mce-content-body textarea:focus {
	color: 				#333;
}
.mce-content-body textarea {
	padding-left: 		3px;
	width: 				98%;
}
.mce-content-body input[type=text] {
	padding: 			3px;
}

/* Links */
.mce-content-body a {
	color: 				#01b;
	text-decoration: 	none;
}
.mce-content-body a:focus,
.mce-content-body a:active,
.mce-content-body a:hover {
	color: 				#b10;
	text-decoration:	none;
}

/* Assistive text */
.assistive-text {
	clip: 				rect(1px 1px 1px 1px); /* IE6, IE7 */
	clip: 				rect(1px, 1px, 1px, 1px);
	position: 			absolute !important;
}

/* Alignment */

.alignleft {
	display: 			inline;
	float: 				left;
	margin-right: 		1.625em;
}
.alignright {
	display: 			inline;
	float: 				right;
	margin-left: 		1.625em;
}
.aligncenter {
	clear: 				both;
	display:			block;
	margin-left: 		auto;
	margin-right: 		auto;
}

.mce-content-body .alignfull,
.mce-content-body .alignwide,
.mce-content-body .aligncenter {
	clear: 				both;
}

.mce-content-body .alignwide,
.mce-content-body p.alighnwide {
	margin-left: 		-10% !important;
	margin-right: 		-10% !important;
	max-width: 			120% !important;
}

.wp-block-text-columns.alignwide {
	margin-left: 		-5% !important;
	margin-right: 		-5% !important;
	max-width: 			110% !important;
	}

/* =HTML Elements */

/* =FONTS -------------------------------------------------- */
/* font family styling for in-line font styling on content elements
 * These are all local to Weaver Xtreme theme - shortened example here...
 *
 */

.mce-content-body .font-sans-serif {
	font-family:        Arial, "Helvetica Neue", Helvetica, sans-serif;
}

.mce-content-body .font-arialBlack {
	font-family:        "Arial Black", Gadget, Helvetica, sans-serif;
}

.mce-content-body .font-arialNarrow {
	font-family:        "Arial Narrow", Arial, sans-serif;
}

.mce-content-body .font-impact {
	font-family:        Impact, Haettenschweiler, Charcoal, "Arial Narrow Bold", sans-serif;
}

.mce-content-body .font-lucidaSans {
	font-family:        "Lucida Sans", Geneva, Tahoma, sans-serif;
}

.mce-content-body .font-trebuchetMS {
	font-family:        "Trebuchet MS", "Lucida Grande", "Lucida Sans Unicode", "Lucida Sans", Tahoma, sans-serif;
}


/* end */