use theme json to disable chart gridlines

Woohoo! Thank you Anonymous! After bashing my head against brackets, braces and commas I got this to work 🙂 Thanks so much for your help! In case it benefits anyone to see where this fell in my file:

{
	"name": "TestTheme",
	"dataColors": [
		"#73B761",
		"#4A588A",
		"#ECC846",
		"#CD4C46",
		"#71AFE2",
		"#8D6FD1",
		"#EE9E64",
		"#95DABB",
		"#8FC581",
		"#6E79A1",
		"#F0D36B",
		"#D7706B",
		"#8DBFE8",
		"#A48CDA",
		"#F1B183",
		"#AAE1C9",
		"#568949",
		"#384268",
		"#B19635",
		"#9A3935",
		"#5583AA",
		"#6A539D",
		"#B3774B",
		"#70A48C",
		"#3A5C31",
		"#252C45",
		"#766423",
		"#672623",
		"#395871",
		"#473869",
		"#774F32",
		"#4B6D5E"
	],
	"background": "#FFFFFF",
	"foreground": "#333333",
	"tableAccent": "#0F1934",
	"visualStyles": {
		"*": {
			"*": {
				"border": [
					{
						"color": {
							"solid": {
								"color": "#CCCCCC"
							}
						},
						"show": true,
						"radius": 7
					}
				],
				"outspacePane": [
					{
						"backgroundColor": {
							"solid": {
								"color": "#FFFFFF"
							}
						},
						"transparency": 0
					}
				],
				"visualTooltip": [
					{
						"titleFontColor": {
							"solid": {
								"color": "#FFFFFF"
							}
						},
						"valueFontColor": {
							"solid": {
								"color": "#FFFFFF"
							}
						}
					}
				],
				"visualHeader": [
					{
						"foreground": {
							"solid": {
								"color": "#666666"
							}
						}
					}
				],
				"background": [
					{
						"color": {
							"solid": {
								"color": "#FFFFFF"
							}
						}
					}
				]
			}
		},
		"columnChart": {
			"*": {
				"general": [
					{
						"responsive": true
					}
				],
				"categoryAxis": [
					{
						"show": true,
						"concatenateLabels": false,
						"showAxisTitle": true,
						"axisStyle": "showTitleOnly",
						"titleText": ""
					}
				],
				"valueAxis": [
					{
						"show": true,
						"labelDisplayUnits": "0",
						"labelPrecision": "0",
						"showAxisTitle": true,
						"axisStyle": "showTitleOnly",
						"titleText": "",
						"gridlineShow": false,
						"gridlineThickness": 2,
						"gridlineStyle": "solid"
					}
				]
			}
		},
		"page": {
			"*": {
				"background": [
					{
						"transparency": 100,
						"color": {
							"solid": {
								"color": "#FFFFFF"
							}
						}
					}
				],
				"outspace": [
					{
						"transparency": 0
					}
				]
			}
		}
	},
	"bad": "#CD4C46",
	"neutral": "#ECC846",
	"good": "#73B761",
	"minimum": "#FFFFFF",
	"center": "#ECC846",
	"maximum": "#73B761",
	"textClasses": {
		"title": {
			"fontFace": "'Segoe UI', wf_segoe-ui_normal, helvetica, arial, sans-serif",
			"color": "#666666",
			"fontSize": 8
		},
		"callout": {
			"fontSize": 27,
			"color": "#353433"
		},
		"label": {
			"fontSize": 9,
			"color": "#777777"
		},
		"header": {
			"fontFace": "'Segoe UI', wf_segoe-ui_normal, helvetica, arial, sans-serif",
			"fontSize": 9
		}
	},
	"foregroundNeutralSecondary": "#999999"
}