:root {
	--panel-bg: #1e2530;
	--panel-border: #333c48;
	--text: #c6d4df;
	--accent: #67c1f5;
}

* {
	box-sizing: border-box;
}

html, body {
	height: 100%;
	margin: 0;
}

body {
	background: #16191f;
	color: var(--text);
	font-family: Arial, Helvetica, sans-serif;
	display: flex;
	flex-direction: column;
}

header.appHeader {
	display: flex;
	align-items: center;
	justify-content: space-between;
	padding: 10px 16px;
	background: var(--panel-bg);
	border-bottom: 1px solid var(--panel-border);
	flex-wrap: wrap;
	gap: 8px;
}

header.appHeader h1 {
	font-size: 16px;
	font-weight: normal;
	margin: 0;
	color: #fff;
}

header.appHeader h1 span {
	color: var(--accent);
}

.modeTabs {
	display: flex;
	gap: 4px;
}

.modeTabs button {
	background: transparent;
	border: 1px solid var(--panel-border);
	color: var(--text);
	padding: 6px 14px;
	font-size: 13px;
	cursor: pointer;
	border-radius: 3px;
}

.modeTabs button.active {
	background: var(--accent);
	color: #0e1720;
	border-color: var(--accent);
	font-weight: bold;
}

.toolbar {
	display: flex;
	flex-wrap: wrap;
	gap: 4px;
	padding: 8px 16px;
	background: #202733;
	border-bottom: 1px solid var(--panel-border);
}

.toolbar button {
	background: #2a3240;
	border: 1px solid var(--panel-border);
	color: var(--text);
	padding: 5px 10px;
	font-size: 12px;
	cursor: pointer;
	border-radius: 3px;
}

.toolbar button:hover {
	background: #333e4e;
	color: #fff;
}

main.workArea {
	flex: 1;
	display: grid;
	gap: 1px;
	background: var(--panel-border);
	overflow: hidden;
}

main.workArea.mode-edit {
	grid-template-columns: 1fr;
}

main.workArea.mode-preview {
	grid-template-columns: 1fr;
}

main.workArea.mode-split {
	grid-template-columns: 1fr 1fr;
}

.mode-edit .previewPane,
.mode-preview .editorPane {
	display: none;
}

.editorPane, .previewPane {
	background: #16191f;
	overflow: auto;
	display: flex;
	flex-direction: column;
}

.paneLabel {
	font-size: 11px;
	text-transform: uppercase;
	letter-spacing: 0.05em;
	color: #6b7684;
	padding: 6px 12px;
	background: #1b2129;
	border-bottom: 1px solid var(--panel-border);
	flex: 0 0 auto;
}

#editor {
	flex: 1;
	width: 100%;
	resize: none;
	border: none;
	outline: none;
	background: #16191f;
	color: #d8e0e8;
	font-family: Consolas, monospace;
	font-size: 13px;
	line-height: 1.5;
	padding: 16px;
}

.previewPane {
	background: #1b2838;
}

.previewScroll {
	flex: 1;
	overflow: auto;
	padding: 24px;
}

.steamPageFrame {
	max-width: 795px;
	margin: 0 auto;
	background: #1b2838;
}

.guideTitleArea {
	border-bottom: 1px solid #3d4450;
	padding-bottom: 12px;
	margin-bottom: 16px;
}

.guideTitleArea .guideTitle {
	font-size: 26px;
	color: #fff;
	font-weight: normal;
	margin: 0 0 6px 0;
}

.guideTitleArea .guideByline {
	font-size: 12px;
	color: #8f98a0;
}

.guideTitleArea .guideByline a {
	color: #67c1f5;
	text-decoration: none;
}

.emptyPreviewHint {
	color: #5c6773;
	font-style: italic;
	font-size: 13px;
}

footer.appFooter {
	padding: 6px 16px;
	font-size: 11px;
	color: #5c6773;
	background: var(--panel-bg);
	border-top: 1px solid var(--panel-border);
	text-align: center;
}

footer.appFooter a {
	color: var(--accent);
}

@media (max-width: 760px) {
	main.workArea.mode-split {
		grid-template-columns: 1fr;
		grid-template-rows: 1fr 1fr;
	}
}