A RichTextPanel definition for matching the word "shield" or "shields" in rich text. It sets styling: no icon, black text color, yellow opaque background and a 5px border radius. Many other style options are present but commented out.
using Sandbox.UI;
[RichTextPanel( @"\b[Ss]hields?\b" )]
public class RichTextShield : RichTextBase
{
public override string Icon => "";
public override Color Color => Color.Black;
public override Color? BackgroundColor => Color.Yellow.WithAlpha(1f);
public override float? BorderRadius => 5f;
//public override int? FontWeight => 800;
//public override float? TextStrokeWidth => 3f;
//public override Color? TextStrokeColor => Color.Yellow;
//public override Color? BackgroundGradientStart => Color.Parse( "#ff0000" );
//public override Color? BackgroundGradientEnd => Color.Parse( "#0000ff" );
//public override float? BackgroundGradientAngle => 45f; // Optional, defaults to 90�
//public override bool Italic => true;
//public override bool Underline => true;
//public override float? TextShadowBlur => 0f;
//public override Color? TextShadowColor => Color.Red;
//public override float? TextShadowOffsetY => -5f;
//public override float? SkewX => 20f;
//public override float? SkewY => 5f;
//public override bool Underline => true;
//public override TextDecorationStyle? UnderlineStyle => TextDecorationStyle.Wavy;
//public override Color? UnderlineColor => Color.Blue;
// Animation properties
//public override string AnimationName => "shake";
//public override float? AnimationDuration => 2f;
//public override string AnimationTimingFunction => "ease-in-out";
//public override string AnimationDirection => "alternate";
//public override string AnimationName => "heartbeat";
//public override float? AnimationDuration => 1.3f;
//public override string AnimationName => "tada";
//public override float? AnimationDuration => 1f;
//public override string AnimationName => "rainbow";
//public override float? AnimationDuration => 3f;
//public override string AnimationTimingFunction => "linear";
//public override string AnimationName => "flash";
//public override float? AnimationDuration => 1f;
}