/* ===========================
   Gradient Descent: overview cards, CTA, scroll hint
   =========================== */
.gd-overview {
  position: absolute;
  right: 2rem;
  bottom: calc(var(--nav-height) + 3rem);
  width: min(680px, calc(100vw - 4rem));
  padding: 1.5rem;
  background: var(--xp-face);
  border-radius: 3px;
  border: 1px solid var(--xp-bevel-shadow);
  box-shadow:
    inset 1px 1px 0 var(--xp-bevel-light),
    inset -1px -1px 0 var(--xp-bevel-dark),
    0 4px 14px rgba(0, 0, 0, 0.35);
  max-height: calc(100vh - var(--nav-height) - 6rem);
  overflow-y: auto;
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.45s cubic-bezier(0.25, 0.1, 0.25, 1), transform 0.45s cubic-bezier(0.25, 0.1, 0.25, 1);
  pointer-events: none;
  z-index: 11;
}

.gd-overview.active {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.gd-overview__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin: -1.5rem -1.5rem 1rem;
  padding: 0.6rem 1.25rem;
  background: linear-gradient(to right, var(--xp-titlebar-dark), var(--xp-titlebar-mid) 70%, var(--xp-titlebar-pale));
  border-radius: 3px 3px 0 0;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.3);
}

.gd-overview__eyebrow {
  font-family: var(--font-hand);
  font-size: 0.8rem;
  color: rgba(255, 255, 255, 0.85);
}

.gd-overview__title {
  margin: 0;
  font-family: var(--font-heading);
  font-size: 1.15rem;
  font-weight: 700;
  color: #fff;
  text-shadow: 0 1px 1px rgba(0, 0, 0, 0.3);
}

.gd-overview__grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.9rem;
}

.gd-overview-cta {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  display: flex;
  gap: 1rem;
  z-index: 12;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.45s cubic-bezier(0.25, 0.1, 0.25, 1);
}

.gd-overview-cta.active {
  opacity: 1;
  pointer-events: auto;
}

.gd-overview-cta__btn {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  font-family: var(--font-hand);
  font-size: 1.05rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: #fff;
  padding: 0.9rem 1.75rem;
  border-radius: 4px;
  background: var(--primary-accent);
  border: 1px solid var(--xp-titlebar-dark);
  box-shadow:
    inset 1px 1px 0 rgba(255, 255, 255, 0.4),
    inset -1px -1px 0 var(--xp-titlebar-dark),
    0 4px 16px rgba(0, 0, 0, 0.4);
  cursor: pointer;
  transition: all 0.15s ease;
}

.gd-overview-cta__btn:hover {
  filter: brightness(1.12);
}

.gd-overview-cta__btn:active {
  box-shadow:
    inset -1px -1px 0 rgba(255, 255, 255, 0.4),
    inset 1px 1px 0 var(--xp-titlebar-dark);
  transform: translateY(1px);
}

.gd-overview-cta__btn .arrow {
  transition: transform 0.3s ease;
}

.gd-overview-cta__btn:hover .arrow {
  transform: translateX(4px);
}

.gd-overview__card {
  display: block;
  padding: 1rem;
  background: var(--xp-face-alt);
  border-radius: 2px;
  border: 1px solid var(--xp-bevel-shadow);
  box-shadow:
    inset 1px 1px 0 var(--xp-bevel-light),
    inset -1px -1px 0 var(--xp-bevel-dark);
  color: inherit;
  text-decoration: none;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.gd-overview__card:hover,
.gd-overview__card:focus-visible {
  transform: translateY(-3px);
  border: 1px solid var(--xp-bevel-shadow);
  box-shadow:
    inset 1px 1px 0 var(--xp-bevel-light),
    inset -1px -1px 0 var(--xp-bevel-dark),
    0 6px 14px rgba(0, 0, 0, 0.25);
}

.gd-overview__card:focus-visible {
  outline: 2px solid var(--primary-accent);
  outline-offset: 2px;
}

.gd-overview__step {
  display: inline-block;
  margin-bottom: 0.45rem;
  font-family: var(--font-hand);
  font-size: 0.8rem;
  color: var(--primary-accent);
}

.gd-overview__award {
  display: flex;
  width: fit-content;
  margin: 0 0 0.55rem;
  padding: 0.28rem 0.52rem;
  font-family: var(--font-hand);
  font-size: 0.75rem;
  color: var(--primary-accent);
  border: 1px solid var(--primary-accent);
}

.gd-overview__card-title {
  margin: 0 0 0.45rem;
  font-family: var(--font-heading);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text);
}

.gd-overview__desc {
  margin: 0;
  font-size: 0.88rem;
  line-height: 1.55;
  color: var(--text-muted);
}

.gd-overview__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.3rem;
  margin-top: 0.6rem;
}

.gd-overview__tag {
  padding: 0.18rem 0.42rem;
  font-family: var(--font-hand);
  font-size: 0.72rem;
  color: var(--text-muted);
  border: 1px solid var(--border);
  border-radius: 2px;
}

/* Scroll hint */
.gd-scroll-hint {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-hand);
  font-size: 1rem;
  font-weight: 700;
  color: #fff;
  padding: 1rem 1.75rem;
  border-radius: 4px;
  background: var(--primary-accent);
  border: 1px solid var(--xp-titlebar-dark);
  box-shadow:
    inset 1px 1px 0 rgba(255, 255, 255, 0.4),
    inset -1px -1px 0 var(--xp-titlebar-dark),
    0 4px 16px rgba(0, 0, 0, 0.45);
  opacity: 1;
  z-index: 4;
  animation: gd-scroll-hint-pulse 1.8s ease-in-out infinite;
  transition: opacity 0.4s ease;
}

.gd-scroll-hint__arrow {
  width: 12px;
  height: 12px;
  border-right: 3px solid #fff;
  border-bottom: 3px solid #fff;
  transform: rotate(45deg);
  animation: gd-scroll-hint-bounce 1.4s ease-in-out infinite;
}

@keyframes gd-scroll-hint-bounce {
  0%, 100% { transform: rotate(45deg) translate(0, 0); }
  50% { transform: rotate(45deg) translate(3px, 3px); }
}

@keyframes gd-scroll-hint-pulse {
  0%, 100% { box-shadow: inset 1px 1px 0 rgba(255, 255, 255, 0.4), inset -1px -1px 0 var(--xp-titlebar-dark), 0 4px 16px rgba(0, 0, 0, 0.45), 0 0 0 0 rgba(36, 94, 220, 0.5); }
  50% { box-shadow: inset 1px 1px 0 rgba(255, 255, 255, 0.4), inset -1px -1px 0 var(--xp-titlebar-dark), 0 4px 16px rgba(0, 0, 0, 0.45), 0 0 0 10px rgba(36, 94, 220, 0); }
}

.gd-scroll-hint.hidden {
  opacity: 0;
  pointer-events: none;
}

/* Screen reader only */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0,0,0,0);
  border: 0;
}