/* Planet art is decorative; navigation, hit areas and orbital positions remain in world.css. */
body.world-page .world-core {
  padding: 0;
  border: 0;
  overflow: visible;
  background: none;
  box-shadow: none;
}

body.world-page .world-orbit .world-core {
  width: clamp(200px, 20vw, 256px);
  top: 37%;
  background: none;
  box-shadow: none;
}

body.world-page .world-core::before,
body.world-page .world-core::after {
  content: none;
}

.world-core-surface,
.island-course-planet::before {
  position: absolute;
  inset: 0;
  z-index: 1;
  border-radius: 50%;
  pointer-events: none;
  background-color: #537d78;
  background-image:
    radial-gradient(ellipse at 28% 24%, rgba(241, 244, 207, 0.16), transparent 44%),
    radial-gradient(ellipse at 27% 26%, transparent 32%, rgba(4, 17, 24, 0.28) 60%, #020910 95%),
    url('/assets/planet-core-terrain-v1.webp');
  background-position: center;
  background-size: cover;
  box-shadow:
    inset 5px 5px 13px rgba(209, 246, 214, 0.32),
    inset -8px -5px 20px rgba(12, 48, 59, 0.46),
    0 0 2px 1px rgba(170, 221, 212, 0.42),
    8px 18px 29px rgba(13, 50, 59, 0.24);
}

.world-core-surface::after {
  content: none;
  position: absolute;
  inset: 0;
  border-radius: inherit;
  background: linear-gradient(
    160deg,
    transparent 37%,
    rgba(2, 13, 19, 0.05) 40%,
    rgba(16, 53, 64, 0.21) 43%,
    transparent 48%
  );
}

.world-core-surface {
  border-radius: 0;
  background: url('/assets/planet-bbs-hub-warm-v4.webp') center / contain no-repeat;
  box-shadow: none;
  filter: drop-shadow(0 10px 12px rgba(113, 79, 45, 0.19));
}

/* Two halves of one tilted ring: the far arc goes behind the opaque globe. */
.world-core-ring {
  position: absolute;
  left: -35%;
  top: 34%;
  width: 170%;
  height: 34%;
  border-radius: 50%;
  background: radial-gradient(
    ellipse at center,
    transparent 51%,
    rgba(172, 131, 85, 0.4) 52%,
    rgba(232, 203, 152, 0.7) 54%,
    rgba(193, 157, 106, 0.75) 56%,
    rgba(255, 234, 190, 0.82) 58%,
    rgba(174, 143, 99, 0.72) 59%,
    rgba(241, 213, 161, 0.86) 61%,
    transparent 62%,
    transparent 64%,
    rgba(204, 178, 135, 0.6) 65%,
    rgba(249, 229, 192, 0.76) 68%,
    transparent 69%
  );
  transform: rotate(-20deg);
  pointer-events: none;
  animation: bbs-ring-drift 18s ease-in-out infinite;
}

.world-core-ring-back {
  z-index: 0;
  clip-path: inset(0 0 50% 0);
  opacity: 0.72;
}

.world-core-ring-front {
  z-index: 2;
  clip-path: inset(50% 0 0 0);
  filter: drop-shadow(0 2px 1px rgba(2, 12, 19, 0.26));
}

body.world-page .world-core-halo {
  z-index: 0;
  inset: -17%;
  border: 0;
  border-radius: 50%;
  background: radial-gradient(
    circle,
    transparent 40%,
    rgba(40, 171, 189, 0.1) 49%,
    rgba(102, 213, 208, 0.21) 57%,
    rgba(102, 213, 208, 0.06) 65%,
    transparent 73%
  );
  box-shadow: none;
  filter: blur(8px);
  pointer-events: none;
  animation: bbs-halo-breathe 7s ease-in-out infinite;
}

.world-core-halo::before {
  content: '';
  position: absolute;
  inset: -3%;
  border-radius: inherit;
  background: conic-gradient(
    from 20deg,
    transparent,
    rgba(148, 236, 225, 0.22) 65deg,
    transparent 140deg,
    rgba(42, 174, 191, 0.18) 235deg,
    transparent 320deg
  );
  mask-image: radial-gradient(circle, transparent 49%, #000 57%, transparent 72%);
  pointer-events: none;
  animation: bbs-halo-flow 28s linear infinite;
}

@keyframes bbs-halo-breathe {
  0%,
  100% {
    opacity: 0.6;
    transform: scale(0.97);
  }
  50% {
    opacity: 0.95;
    transform: scale(1.06);
  }
}

@keyframes bbs-halo-flow {
  to {
    transform: rotate(360deg);
  }
}

@keyframes bbs-ring-drift {
  0%,
  100% {
    transform: rotate(-20deg);
  }
  50% {
    transform: rotate(-15deg);
  }
}

@media (prefers-reduced-motion: reduce) {
  body.world-page .world-core-halo,
  body.world-page .world-core-halo::before,
  body.world-page .world-core-ring {
    animation: none !important;
  }
}

body.world-page .world-orbit .world-core > .world-core-identity {
  position: absolute;
  z-index: 4;
  bottom: -6%;
  left: 50%;
  width: 128%;
  min-width: 260px;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  align-items: center;
  gap: 10px;
  padding: 9px 11px;
  border: 1px solid var(--world-line);
  border-radius: 12px;
  background: var(--world-panel-strong);
  color: var(--world-paper) !important;
  box-shadow: 0 8px 18px rgba(2, 16, 24, 0.17);
  transform: translateX(-50%);
  text-align: left;
}

body.world-page .world-orbit .world-core-identity img {
  width: 32px;
  border-radius: 7px;
  filter: none;
}

.world-core-copy {
  min-width: 0;
  display: grid;
  gap: 5px;
}

body.world-page .world-orbit .world-core-kicker {
  margin: 0;
  color: var(--world-muted) !important;
  font-family: var(--font-latin), var(--font-zh-ui);
  font-size: 14px;
  font-weight: 600;
  line-height: 1.2;
  letter-spacing: 0.05em;
}

body.world-page .world-orbit .world-core strong {
  color: var(--world-paper) !important;
  font-family: var(--font-latin), var(--font-zh-title);
  font-size: clamp(28px, 2.4vw, 34px);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: 0;
  white-space: nowrap;
}

.world-core-description {
  color: var(--world-muted) !important;
  font-family: var(--font-zh-body);
  font-size: 16px;
  line-height: 1.35;
}

body.world-page .island-course-planet {
  --course-art-image: none;
  padding: 0;
  border: 0;
  background: none;
  box-shadow: none;
  backdrop-filter: none;
  -webkit-backdrop-filter: none;
}

body.world-page .island-course-planet::before {
  content: '';
  inset: 0;
  width: auto;
  height: auto;
  border: 0;
  /* Keep domes, towers and waterfalls intact instead of cropping to a sphere. */
  border-radius: 0;
  background: var(--course-art-image) center / contain no-repeat;
  box-shadow: none;
  transform: none;
  filter: drop-shadow(0 7px 9px rgba(5, 49, 55, 0.24));
}

body.world-page .island-course-planet::after {
  /* The course-specific symbols now belong to the illustrated terrain itself. */
  content: none;
  background: none;
  box-shadow: none;
  mask-image: none;
}

body.world-page .island-course-planet[data-course-slug='math'] {
  --course-accent: #9dddab;
  --course-art-image: url('/assets/course-planet-math-v2.webp');
}

body.world-page .island-course-planet[data-course-slug='circuits'] {
  --course-accent: #e9c679;
  --course-art-image: url('/assets/course-planet-circuits-v2.webp');
}

body.world-page .island-course-planet[data-course-slug='signals'] {
  --course-accent: #91dcee;
  --course-art-image: url('/assets/course-planet-signals-v2.webp');
}

@media (max-width: 640px) {
  body.world-page .island-course-planet[data-course-slug='math'] {
    --course-art-image: url('/assets/course-planet-math-v2-mobile.webp');
  }

  body.world-page .island-course-planet[data-course-slug='circuits'] {
    --course-art-image: url('/assets/course-planet-circuits-v2-mobile.webp');
  }

  body.world-page .island-course-planet[data-course-slug='signals'] {
    --course-art-image: url('/assets/course-planet-signals-v2-mobile.webp');
  }
}

body.world-page .island-course-planet > .island-course-identity {
  position: absolute;
  z-index: 3;
  bottom: -20%;
  left: 50%;
  display: grid;
  width: 118%;
  gap: 4px;
  padding: 10px 12px;
  overflow: visible;
  border: 1px solid var(--world-line);
  border-radius: 12px;
  background: var(--world-panel-strong);
  box-shadow: 0 8px 20px rgba(2, 16, 24, 0.15);
  transform: translateX(-50%);
  -webkit-line-clamp: unset;
}

.island-course-identity > small {
  color: var(--world-muted) !important;
  font-family: var(--font-latin), var(--font-zh-ui);
  font-size: clamp(11px, 0.6rem, 14px);
  font-weight: 600;
  letter-spacing: 0.07em;
  line-height: 1.2;
}

.island-course-identity > strong {
  color: var(--world-paper) !important;
  font-family: var(--font-zh-title);
  font-size: clamp(18px, 1.1rem, 24px);
  line-height: 1.3;
  text-wrap: balance;
}

.island-course-identity > span:not(.island-course-action) {
  color: var(--world-muted) !important;
  font-family: var(--font-zh-body);
  font-size: clamp(13px, 0.75rem, 16px);
  line-height: 1.45;
}

.island-course-identity > .island-course-action {
  color: var(--world-paper) !important;
  font-family: var(--font-zh-ui);
  font-size: clamp(14px, 0.8rem, 18px);
  line-height: 1.3;
}

@media (hover: hover) and (pointer: fine) {
  body.world-page .island-course-planet:hover {
    box-shadow: none;
  }

  .island-course-planet:hover .island-course-identity {
    border-color: var(--course-accent);
  }
}

@media (max-width: 640px) {
  body.world-page .world-explorer {
    padding-top: 96px;
  }

  body.world-page .world-orbit .world-core {
    width: 146px;
    top: 25%;
    /* Keep the central identity in front of neighbouring island art on narrow screens. */
    transform: translateZ(130px);
  }

  body.world-page .world-orbit .world-core > .world-core-identity {
    width: 136%;
    min-width: 196px;
    gap: 6px;
    padding: 7px 8px;
    border-radius: 10px;
  }

  .world-core-description,
  body.world-page .world-orbit .world-core-kicker {
    display: block;
    font-size: 14px;
  }

  body.world-page .world-orbit .world-core strong {
    font-size: clamp(20px, 5.6vw, 24px);
  }

  body.world-page .world-orbit .world-core-identity img {
    width: 24px;
  }

  .island-course-node {
    margin-bottom: 65px;
  }

  body.world-page .island-course-planet > .island-course-identity {
    width: 110%;
    padding: 9px;
  }

  .island-course-identity > strong {
    font-size: 18px;
  }
}