Blender Theme - Ryo Blue #005cdd -- Save somewhere, go to Blender Preferences > Themes > Install and select XML file.

Ryo-Blue.xml

<bpy>
  <Theme>
    <user_interface>
      <ThemeUserInterface
        >
        <wcol_regular>
          <ThemeWidgetColors
            inner_sel="#005cdd"
            >
          </ThemeWidgetColors>
        </wcol_regular>
        <wcol_tool>
          <ThemeWidgetColors
            inner_sel="#005cdd"
            >
          </ThemeWidgetColors>
        </wcol_tool>
        <wcol_toolbar_item>
          <ThemeWidgetColors
            inner_sel="#005cdd"
            >
          </ThemeWidgetColors>
        </wcol_toolbar_item>
        <wcol_radio>
          <ThemeWidgetColors
            inner_sel="#005cdd"
            >
          </ThemeWidgetColors>
        </wcol_radio>
        <wcol_text>
          <ThemeWidgetColors
            item="#005cdd"
            >
          </ThemeWidgetColors>
        </wcol_text>
        <wcol_option>
          <ThemeWidgetColors
            inner_sel="#005cdd"
            >
          </ThemeWidgetColors>
        </wcol_option>
        <wcol_toggle>
          <ThemeWidgetColors
            inner_sel="#005cdd"
            >
          </ThemeWidgetColors>
        </wcol_toggle>
        <wcol_num>
          <ThemeWidgetColors
            item="#005cdd"
            >
          </ThemeWidgetColors>
        </wcol_num>
        <wcol_numslider>
          <ThemeWidgetColors
            item="#005cdd"
            >
          </ThemeWidgetColors>
        </wcol_numslider>
        <wcol_menu>
          <ThemeWidgetColors
            inner_sel="#0284c7b3"
            >
          </ThemeWidgetColors>
        </wcol_menu>
        <wcol_pulldown>
          <ThemeWidgetColors
            inner_sel="#0284c7b3"
            >
          </ThemeWidgetColors>
        </wcol_pulldown>
        <wcol_menu_back>
          <ThemeWidgetColors
            inner_sel="#005cdd"
            >
          </ThemeWidgetColors>
        </wcol_menu_back>
        <wcol_pie_menu>
          <ThemeWidgetColors
            inner_sel="#005cdd"
            >
          </ThemeWidgetColors>
        </wcol_pie_menu>
        <wcol_tooltip>
          <ThemeWidgetColors
            inner_sel="#005cdd"
            >
          </ThemeWidgetColors>
        </wcol_tooltip>
        <wcol_menu_item>
          <ThemeWidgetColors
            inner_sel="#005cdd"
            >
          </ThemeWidgetColors>
        </wcol_menu_item>
        <wcol_progress>
          <ThemeWidgetColors
            inner_sel="#005cdd"
            item="#005cdd"
            >
          </ThemeWidgetColors>
        </wcol_progress>
        <wcol_list_item>
          <ThemeWidgetColors
            item="#005cdd"
            >
          </ThemeWidgetColors>
        </wcol_list_item>
      </ThemeUserInterface>
    </user_interface>
    <view_3d>
      <ThemeView3D
        frame_current="#0284c7"
        >
      </ThemeView3D>
    </view_3d>
    <graph_editor>
      <ThemeGraphEditor
        frame_current="#0284c7"
        >
      </ThemeGraphEditor>
    </graph_editor>
    <file_browser>
      <ThemeFileBrowser
        selected_file="#0284c7"
        >
      </ThemeFileBrowser>
    </file_browser>
    <nla_editor>
      <ThemeNLAEditor
        frame_current="#0284c7"
        >
      </ThemeNLAEditor>
    </nla_editor>
    <dopesheet_editor>
      <ThemeDopeSheet
        frame_current="#0284c7"
        >
      </ThemeDopeSheet>
    </dopesheet_editor>
    <image_editor>
      <ThemeImageEditor
        frame_current="#0284c7"
        >
      </ThemeImageEditor>
    </image_editor>
    <sequence_editor>
      <ThemeSequenceEditor
        frame_current="#0284c7"
        >
      </ThemeSequenceEditor>
    </sequence_editor>
    <properties>
      <ThemeProperties
        match="#0284c7"
        active_modifier="#005cdd"
        >
      </ThemeProperties>
    </properties>
    <outliner>
      <ThemeOutliner
        selected_highlight="#013550"
        active="#014f77"
        >
      </ThemeOutliner>
    </outliner>
    <clip_editor>
      <ThemeClipEditor
        frame_current="#0284c7"
        >
      </ThemeClipEditor>
    </clip_editor>
  </Theme>
  <ThemeStyle>
  </ThemeStyle>
</bpy>