Candy Button

import { cn } from "~/lib/utils";

export interface CandyButtonProps
  extends React.ButtonHTMLAttributes<HTMLButtonElement> {
  /** Optional leading icon (e.g. a lucide <Plus />). */
  icon?: React.ReactNode;
  /** Base color; the gloss, ring, and every state derive from it. Default #296FF0. */
  color?: string;
  /** Corner radius in px. Default 18. */
  radius?: number;
  /** Label / icon color. Default #fff. */
  labelColor?: string;
}

/**
 * A glossy, 3D "candy" call-to-action. The puffed look is all box-shadow:
 * a bottom drop shadow for elevation, a 1px edge ring, a 1px inset white
 * stroke, and an inset white top sheen for the gloss. Everything themes off a
 * single `--candy-color`, so passing `color` recolors the whole button —
 * gradient, ring, hover glow, and focus outline included. Styling lives in
 * `.btn-candy` (app.css), so it works with or without Tailwind.
 */
export function CandyButton({
  icon,
  color,
  radius,
  labelColor,
  children,
  className,
  type = "button",
  style,
  ...props
}: CandyButtonProps) {
  const vars: React.CSSProperties = { ...style };
  if (color) (vars as Record<string, string>)["--candy-color"] = color;
  if (radius != null)
    (vars as Record<string, string>)["--candy-radius"] = `${radius}px`;
  if (labelColor) (vars as Record<string, string>)["--candy-label"] = labelColor;

  return (
    <button type={type} className={cn("btn-candy", className)} style={vars} {...props}>
      {icon ? <span className="btn-candy__icon">{icon}</span> : null}
      {children}
    </button>
  );
}

/* ─── Candy CTA button (glossy 3D) ─────────────────────────────────── */
.btn-candy {
  /* Everything derives from one base color, so the whole button is themeable
     by setting --candy-color (and optionally --candy-radius / --candy-label). */
  --candy-color: #296ff0;
  --candy-radius: 18px;
  --candy-label: #fff;
  --candy-top: color-mix(in srgb, var(--candy-color) 78%, #fff);
  --candy-press: color-mix(in srgb, var(--candy-color) 82%, #000);
  --lift: 0px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.6rem;
  cursor: pointer;
  border: none;
  color: var(--candy-label);
  border-radius: var(--candy-radius);
  padding: 0.95rem 1.9rem;
  font-family: var(--font-sans);
  font-size: 1.125rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  background: linear-gradient(180deg, var(--candy-top), var(--candy-color));
  box-shadow:
    0 3px 6px rgba(0, 0, 0, 0.2),                  /* 1. drop shadow    */
    0 0 0 1px var(--candy-color),                   /* 3. edge ring      */
    inset 0 0 0 1px rgba(255, 255, 255, 0.4),       /* stroke: white 40% */
    inset 0 1px 6px 2px rgba(255, 255, 255, 0.24);  /* 2. inner sheen    */
  transform: translateY(var(--lift));
  transition:
    transform 0.16s cubic-bezier(0.2, 0.7, 0.2, 1),
    box-shadow 0.16s ease,
    filter 0.16s ease;
}
.btn-candy:hover {
  --lift: -2px;
  filter: brightness(1.05);
  box-shadow:
    0 8px 18px color-mix(in srgb, var(--candy-color) 38%, transparent),
    0 0 0 1px var(--candy-color),
    inset 0 0 0 1px rgba(255, 255, 255, 0.45),
    inset 0 1px 6px 2px rgba(255, 255, 255, 0.3);
}
.btn-candy:active {
  --lift: 1px;
  filter: brightness(0.97);
  transform: translateY(1px) scale(0.99);
  box-shadow:
    0 1px 3px rgba(0, 0, 0, 0.25),
    0 0 0 1px var(--candy-press),
    inset 0 2px 6px rgba(0, 0, 0, 0.2);
}
.btn-candy:focus-visible {
  outline: 3px solid color-mix(in srgb, var(--candy-color) 45%, transparent);
  outline-offset: 2px;
}
.btn-candy:disabled {
  cursor: not-allowed;
  opacity: 0.55;
  filter: none;
  --lift: 0px;
}
.btn-candy__icon {
  display: inline-flex;
  font-size: 1.25em;
  line-height: 0;
}
@media (prefers-reduced-motion: reduce) {
  .btn-candy {
    transition: none;
  }
}