Modify the default font of extjs4

[Css]
. X-btn-default-small. x-btn-inner ,. x-btn-default-medium. x-btn-inner ,. x-btn-default-large. x-btn-inner ,. x-btn-default-toolbar-small. x-btn-inner ,. x-btn-default-toolbar-medium. x-btn-inner ,. x-btn-default-toolbar-large. x-btn-inner ,. x-menu-item-text ,. x-html-editor-tb. x-font-select ,. x-panel-header-default ,. x-panel-header-text-default ,. x-panel-header-default-framed ,. x-tip-header ,. x-tip-body ,. x-form-invalid-tip-body ,. x-tip-header-text ,. x-progress-text ,. x-toolbar ,. x-toolbar. x-form-item-label ,. x-toolbar. x-toolbar-text ,. x-window-header-text-default ,. x-tab-bar ,. x-tab button ,. x-grid-rowbody ,. x-grid-row. x-grid-cell ,. x-grid-group-title ,. x-grid-row-editor. x-form-field ,. x-grid-row-editor. x-form-display-field ,. x-form-invalid-under ,. x-fieldset-header ,. x-column-header ,. x-mask-msg div ,. x-btn-group-header-text-default-framed, table. x-datepicker-inner ,. x-monthpicker-item ,. x-dd-drag-ghost
{
Font-size: 12px;
}

. X-column-header
{
Text-shadow: 0 0 0 rgba (255,255,255, 0.3 );
}

Modify ext-all.css and add it to the end of the page. For more information, see