Theme question about Filter panel and Filter card

Hi Anonymous ,

Based on my research, we could change the Input box color to meet your requirement.

{ 
    "name":"PowerBI Demo",
    "dataColors":[ 
        "#003366",
        "#A8C5E0",
        "#214F80",
        "#A4D3E3",
        "#82A1BD",
        "#366996",
        "#304E64",
        "#004576",
        "#666666",
        "#000000",
        "#0C304A",
        "#0076DE"
    ],
    "background":"#FFFFFF",
    "foreground":"#003366",
    "tableAccent":"#214F80",
    "visualStyles":{ 
        "page":{ 
            "*":{ 
                "outspacePane":[ 
                    { 
                        "backgroundColor":{ 
                            "solid":{ 
                                "color":"#0000ff"
                            }
                        },
                        "foregroundColor":{ 
                            "solid":{ 
                                "color":"#00ff00"
                            }
                        },
                        "transparency":50,
                        "titleSize":35,
                        "headerSize":8,
                        "fontFamily":"Georgia",
                        "border":true,
                        "borderColor":{ 
                            "solid":{ 
                                "color":"#ff0000"
                            }
                        }
                    }
                ],
                "filterCard":[ 
                    { 
                        "$id":"Applied",
                        "transparency":0,
                        "backgroundColor":{ 
                            "solid":{ 
                                "color":"#ff0000"
                            }
                        },
                        "foregroundColor":{ 
                            "solid":{ 
                                "color":"#45f442"
                            }
                        },
                        "textSize":30,
                        "fontFamily":"Arial",
                        "border":true,
                        "borderColor":{ 
                            "solid":{ 
                                "color":"#ffffff"
                            }
                        },
                        "inputBoxColor":{ 
                            "solid":{ 
                                "color":"#C8C8C8"
                            }
                        }
                    },
                    { 
                        "$id":"Available",
                        "transparency":40,
                        "backgroundColor":{ 
                            "solid":{ 
                                "color":"#00ff00"
                            }
                        },
                        "foregroundColor":{ 
                            "solid":{ 
                                "color":"#ffffff"
                            }
                        },
                        "textSize":10,
                        "fontFamily":"Times New Roman",
                        "border":true,
                        "borderColor":{ 
                            "solid":{ 
                                "color":"#123456"
                            }
                        },
                        "inputBoxColor":{ 
                            "solid":{ 
                                "color":"#777777"
                            }
                        }
                    }
                ]
            }
        }
    }
}

Please refer to the similar Thread and Documents:

https://community.powerbi.com/t5/Desktop/Custom-Theme-for-new-Filter-Pane/td-p/576283

https://docs.microsoft.com/en-us/power-bi/power-bi-report-filter#theming-for-filter-pane

https://docs.microsoft.com/en-us/power-bi/desktop-report-themes#report-theme-json-file-format

BTW, json as attached.

Best regards,

Community Support Team _ Dong Li
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