.lms-checkbox {
  --checkbox-size: 28px;
  --checkbox-color: var(--brand-secondary, #0C8FF9);
  --checkbox-deep: #0875d0;
  --checkbox-glow: #82ccfe;
  --checkbox-spark: #b9e3ff;
  position: relative;
  display: inline-block;
  flex: 0 0 var(--checkbox-size);
  width: var(--checkbox-size);
  height: var(--checkbox-size);
  border-radius: 8px;
  vertical-align: middle;
  -webkit-tap-highlight-color: transparent;
}

/* Keep the native input available to keyboard navigation and screen readers. */
.lms-checkbox > input[type="checkbox"] {
  position: absolute;
  inset: 0;
  z-index: 4;
  width: 100%;
  height: 100%;
  margin: 0;
  opacity: 0;
  cursor: pointer;
}

.lms-checkbox__visual {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 2px solid #8b8fa3;
  border-radius: 8px;
  pointer-events: none;
  transition: border-color .3s, box-shadow .3s,
    transform .3s cubic-bezier(.34, 1.56, .64, 1);
}

.lms-checkbox__bg {
  position: absolute;
  inset: 0;
  z-index: 1;
  border-radius: 6px;
  background: linear-gradient(135deg, var(--checkbox-deep), var(--checkbox-color));
  opacity: 0;
  transform: scale(.5);
  transition: opacity .4s ease, transform .4s cubic-bezier(.34, 1.56, .64, 1), box-shadow .4s;
}

.lms-checkbox__visual svg {
  position: relative;
  z-index: 2;
  width: 16px;
  height: 16px;
  stroke: #fff;
  stroke-width: 2.5;
  stroke-linecap: round;
  stroke-linejoin: round;
  opacity: 0;
  transform: scale(0) rotate(-20deg);
  transition: opacity .25s ease, transform .4s cubic-bezier(.34, 1.56, .64, 1);
}

.lms-checkbox__tick {
  stroke-dasharray: 28;
  stroke-dashoffset: 28;
  transition: stroke-dashoffset .5s cubic-bezier(.65, 0, .35, 1) .15s;
}
.lms-checkbox__dash { opacity: 0; }

.lms-checkbox__particle,
.lms-checkbox__spark {
  position: absolute;
  top: 50%;
  left: 50%;
  z-index: 3;
  opacity: 0;
  pointer-events: none;
}
.lms-checkbox__particle {
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--particle-color, var(--checkbox-spark));
}
.lms-checkbox__particle--1 { --angle: -45deg; --distance: 22px; --time: .65s; --delay: 0s; }
.lms-checkbox__particle--2 { --angle: -90deg; --distance: 26px; --time: .6s; --delay: .05s; --particle-color: var(--checkbox-glow); }
.lms-checkbox__particle--3 { --angle: 0deg; --distance: 20px; --time: .55s; --delay: .08s; --particle-color: #4fb0fb; }
.lms-checkbox__particle--4 { --angle: 45deg; --distance: 24px; --time: .7s; --delay: .03s; --particle-color: var(--checkbox-color); }
.lms-checkbox__particle--5 { --angle: 135deg; --distance: 18px; --time: .5s; --delay: .1s; --particle-color: #d9ecfe; }
.lms-checkbox__particle--6 { --angle: -135deg; --distance: 23px; --time: .65s; --delay: .06s; --particle-color: var(--checkbox-deep); }

.lms-checkbox__ring {
  position: absolute;
  inset: -8px;
  z-index: 1;
  border: 2px solid var(--checkbox-glow);
  border-radius: 50%;
  opacity: 0;
  pointer-events: none;
}
.lms-checkbox__ring--1 { --delay: 0s; }
.lms-checkbox__ring--2 { --delay: .12s; }
.lms-checkbox__ring--3 { --delay: .24s; }

.lms-checkbox__spark {
  width: 2px;
  height: 10px;
  border-radius: 2px;
  background: linear-gradient(to top, var(--checkbox-spark), transparent);
  transform-origin: center;
  transform: rotate(var(--rotation)) translateY(-2px);
}
.lms-checkbox__spark--1 { --rotation: 0deg; --time: .5s; --delay: .05s; }
.lms-checkbox__spark--2 { --rotation: 45deg; --time: .45s; --delay: .08s; }
.lms-checkbox__spark--3 { --rotation: 90deg; --time: .5s; --delay: .03s; }
.lms-checkbox__spark--4 { --rotation: 135deg; --time: .55s; --delay: .1s; }
.lms-checkbox__spark--5 { --rotation: 180deg; --time: .5s; --delay: .06s; }
.lms-checkbox__spark--6 { --rotation: 225deg; --time: .45s; --delay: .09s; }
.lms-checkbox__spark--7 { --rotation: 270deg; --time: .5s; --delay: .04s; }
.lms-checkbox__spark--8 { --rotation: 315deg; --time: .55s; --delay: .07s; }

.lms-checkbox__visual::before {
  content: "";
  position: absolute;
  inset: -3px;
  border-radius: 10px;
  background: radial-gradient(circle, rgba(12, 143, 249, .12), transparent 70%);
  opacity: 0;
  animation: lms-checkbox-breathe 3s ease-in-out infinite;
}
.lms-checkbox__visual::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 2;
  border-radius: 6px;
  background: linear-gradient(135deg, rgba(255, 255, 255, .25), transparent 50%, rgba(255, 255, 255, .1));
  opacity: 0;
  transition: opacity .4s .2s;
}

.lms-checkbox > input:is(:checked, :indeterminate) + .lms-checkbox__visual {
  border-color: var(--checkbox-color);
  animation: lms-checkbox-pulse .5s ease;
}
.lms-checkbox > input:is(:checked, :indeterminate) + .lms-checkbox__visual .lms-checkbox__bg {
  opacity: 1;
  transform: scale(1);
  box-shadow: 0 0 12px rgba(12, 143, 249, .5), 0 0 30px rgba(12, 143, 249, .2), inset 0 0 8px rgba(217, 236, 254, .15);
}
.lms-checkbox > input:is(:checked, :indeterminate) + .lms-checkbox__visual svg {
  opacity: 1;
  transform: scale(1) rotate(0deg);
}
.lms-checkbox > input:checked + .lms-checkbox__visual .lms-checkbox__tick { stroke-dashoffset: 0; }
.lms-checkbox > input:indeterminate + .lms-checkbox__visual .lms-checkbox__tick { opacity: 0; }
.lms-checkbox > input:indeterminate + .lms-checkbox__visual .lms-checkbox__dash { opacity: 1; }

.lms-checkbox > input:checked + .lms-checkbox__visual .lms-checkbox__particle {
  animation: lms-checkbox-particle var(--time) var(--delay) ease-out forwards;
}
.lms-checkbox > input:checked + .lms-checkbox__visual .lms-checkbox__ring {
  animation: lms-checkbox-shockwave .7s var(--delay) ease-out forwards;
}
.lms-checkbox > input:checked + .lms-checkbox__visual .lms-checkbox__spark {
  animation: lms-checkbox-spark var(--time) var(--delay) ease-out forwards;
}
.lms-checkbox > input:is(:checked, :indeterminate) + .lms-checkbox__visual::before {
  animation: none;
  opacity: .6;
  transform: scale(1.2);
  background: radial-gradient(circle, rgba(12, 143, 249, .25), transparent 70%);
  transition: opacity .5s, transform .5s;
}
.lms-checkbox > input:is(:checked, :indeterminate) + .lms-checkbox__visual::after { opacity: 1; }

.lms-checkbox > input:hover:not(:disabled) + .lms-checkbox__visual {
  border-color: var(--checkbox-glow);
  box-shadow: 0 0 8px rgba(12, 143, 249, .25);
}
.lms-checkbox > input:focus-visible + .lms-checkbox__visual {
  outline: 2px solid var(--checkbox-color);
  outline-offset: 3px;
}
.lms-checkbox > input:disabled { cursor: not-allowed; }
.lms-checkbox > input:disabled + .lms-checkbox__visual { opacity: .45; }
.lms-checkbox > input:disabled + .lms-checkbox__visual,
.lms-checkbox > input:disabled + .lms-checkbox__visual :is(.lms-checkbox__particle, .lms-checkbox__ring, .lms-checkbox__spark),
.lms-checkbox > input:disabled + .lms-checkbox__visual::before { animation: none; }

.lms-checkbox:has(> input.is-invalid) .lms-checkbox__visual,
.was-validated .lms-checkbox:has(> input:invalid) .lms-checkbox__visual { border-color: var(--checkbox-color); }
.lms-checkbox:has(> input.is-invalid) ~ .invalid-feedback,
.was-validated .lms-checkbox:has(> input:invalid) ~ .invalid-feedback { display: block; }
.dashboard-profile-consent > .lms-checkbox { margin-top: 1px; }
.dashboard-profile-consent .invalid-feedback { padding-left: 38px; }

/* Preserve the lesson grid's 32px column without the old circular badge. */
.lesson > .lms-checkbox { justify-self: center; background: transparent; box-shadow: none; }

@keyframes lms-checkbox-pulse {
  0%, 100% { transform: scale(1); }
  30% { transform: scale(.85); }
  60% { transform: scale(1.15); }
}
@keyframes lms-checkbox-particle {
  0% { opacity: 1; transform: translate(-50%, -50%) rotate(var(--angle)) translateY(0) scale(1); }
  60% { opacity: 1; transform: translate(-50%, -50%) rotate(var(--angle)) translateY(calc(var(--distance) * -1)) scale(1.1); }
  100% { opacity: 0; transform: translate(-50%, -50%) rotate(var(--angle)) translateY(calc(var(--distance) * -1.4)) scale(0); }
}
@keyframes lms-checkbox-shockwave {
  0% { opacity: .7; transform: scale(.5); border-color: var(--checkbox-glow); }
  50% { opacity: .4; border-color: var(--checkbox-spark); }
  100% { opacity: 0; transform: scale(2.2); border-color: transparent; }
}
@keyframes lms-checkbox-spark {
  0% { opacity: 1; transform: rotate(var(--rotation)) translateY(-4px) scaleY(.5); }
  50% { opacity: .9; transform: rotate(var(--rotation)) translateY(-20px) scaleY(1.2); background: linear-gradient(to top, var(--checkbox-color), transparent); }
  100% { opacity: 0; transform: rotate(var(--rotation)) translateY(-30px) scaleY(.3); }
}
@keyframes lms-checkbox-breathe {
  0%, 100% { opacity: 0; transform: scale(.95); }
  50% { opacity: 1; transform: scale(1.15); }
}

@media (prefers-reduced-motion: reduce) {
  .lms-checkbox *, .lms-checkbox *::before, .lms-checkbox *::after {
    animation: none !important;
    transition: none !important;
  }
}
@media (forced-colors: active) {
  .lms-checkbox__visual { forced-color-adjust: none; border-color: CanvasText; }
  .lms-checkbox { --checkbox-color: Highlight; --checkbox-deep: Highlight; --checkbox-glow: Highlight; }
  .lms-checkbox__visual svg { stroke: HighlightText; }
}