vscode-custom.css

/* .monaco-editor .lines-content .core-guide-indent {
    background-image: linear-gradient(to bottom, #bbb 50%, transparent 50%);
    background-repeat: repeat-y;
    background-size: 2px 6px;
    border-left: none;
    box-shadow: none;
}

.monaco-editor .lines-content .core-guide-indent.indent-active {
    background-image: linear-gradient(to bottom, #555 50%, transparent 50%);
    background-repeat: repeat-y;
    background-size: 2px 6px;
    border-left: none;
    box-shadow: none;
} */

/* すべてのインデントガイドを直線に設定 */
.monaco-editor .lines-content .core-guide-indent {
	border-left: 2px solid #bbb;
	background-image: none;
	box-shadow: none;
}

.monaco-editor .lines-content .core-guide-indent.indent-active {
	border-left: 2px solid #555;
	background-image: none;
	box-shadow: none;
}

/* 2レベル目以降のインデントガイドを点線に設定 */
/* .monaco-editor .lines-content .core-guide-indent.lvl-1,
.monaco-editor .lines-content .core-guide-indent.lvl-2,
.monaco-editor .lines-content .core-guide-indent.lvl-3,
.monaco-editor .lines-content .core-guide-indent.lvl-4,
.monaco-editor .lines-content .core-guide-indent.lvl-5,
.monaco-editor .lines-content .core-guide-indent.lvl-6,
.monaco-editor .lines-content .core-guide-indent.lvl-7,
.monaco-editor .lines-content .core-guide-indent.lvl-8,
.monaco-editor .lines-content .core-guide-indent.lvl-9,
.monaco-editor .lines-content .core-guide-indent.lvl-10 {
	background-image: linear-gradient(to bottom, #bbb 50%, transparent 50%);
	background-repeat: repeat-y;
	background-size: 2px 6px;
	border-left: none;
}

.monaco-editor .lines-content .core-guide-indent.lvl-1.indent-active,
.monaco-editor .lines-content .core-guide-indent.lvl-2.indent-active,
.monaco-editor .lines-content .core-guide-indent.lvl-3.indent-active,
.monaco-editor .lines-content .core-guide-indent.lvl-4.indent-active,
.monaco-editor .lines-content .core-guide-indent.lvl-5.indent-active,
.monaco-editor .lines-content .core-guide-indent.lvl-6.indent-active,
.monaco-editor .lines-content .core-guide-indent.lvl-7.indent-active,
.monaco-editor .lines-content .core-guide-indent.lvl-8.indent-active,
.monaco-editor .lines-content .core-guide-indent.lvl-9.indent-active,
.monaco-editor .lines-content .core-guide-indent.lvl-10.indent-active {
	background-image: linear-gradient(to bottom, #555 50%, transparent 50%);
	background-repeat: repeat-y;
	background-size: 2px 6px;
	border-left: none;
} */

/* 折りたたみインジケータを常に表示 */
.monaco-editor .cldr.codicon-folding-expanded,
.monaco-editor .cldr.codicon-folding-collapsed {
	opacity: 1 !important;
}

/* 折りたたみインジケータを四角で囲む */
.monaco-editor .cldr.codicon-folding-expanded:before,
.monaco-editor .cldr.codicon-folding-collapsed:before {
	border: 2px solid #555;
	font-weight: bold;
	font-size: 13px;
	border-radius: 1px;
	color: #fff;
}

/* 2レベル目以降のインデントガイドを点線に設定（1番目を除く） */
.monaco-editor .lines-content .core-guide-indent[class*='lvl-']:not(.lvl-0) {
	background-image: linear-gradient(to bottom, #bbb 50%, transparent 50%);
	background-repeat: repeat-y;
	background-size: 2px 6px;
	border-left: none;
}

.monaco-editor .lines-content .core-guide-indent[class*='lvl-'].indent-active:not(.lvl-0) {
	background-image: linear-gradient(to bottom, #555 50%, transparent 50%);
	border-left: none;
	box-shadow: none;
}