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/* Big Bang module — timeline, particle taxonomy, and clearly marked illustrative art. */
.hp-bigbang-boundary{display:flex;gap:.7rem;align-items:flex-start;margin:1rem 0;padding:1rem;border:1px solid color-mix(in srgb,var(--warning) 42%,transparent);border-left:4px solid var(--warning);border-radius:0 15px 15px 0;background:color-mix(in srgb,var(--warning) 9%,transparent);line-height:1.55}.hp-bigbang-boundary iconify-icon{flex:0 0 auto;color:var(--warning);font-size:1.4rem}.hp-bb-visual-grid,.hp-bb-zoo-grid{display:grid;grid-template-columns:minmax(0,1.2fr) minmax(280px,.8fr);gap:1rem}.hp-bb-canvas-card{overflow:hidden}.hp-bb-canvas-card canvas{width:100%;height:auto;display:block;border-radius:14px;background:var(--bg-deep)}.hp-bb-scrubber{margin:.8rem 0 0}.hp-bb-detail{display:flex;flex-direction:column;gap:.8rem}.hp-bb-detail h3,.hp-bb-zoo h3,.hp-bb-higgs h3,.hp-bb-art h3{margin:0;font-size:1.22rem}.hp-bb-detail dl{display:grid;grid-template-columns:1fr;gap:.2rem;margin:0;padding:.75rem;border-radius:12px;background:var(--bg-deep)}.hp-bb-detail dt{font-size:.68rem;font-weight:800;letter-spacing:.08em;text-transform:uppercase;color:var(--muted)}.hp-bb-detail dd{margin:0 0 .5rem;color:var(--text);line-height:1.45}.hp-bb-detail dd:last-child{margin-bottom:0}.hp-bb-detail p,.hp-bb-zoo p,.hp-bb-higgs p,.hp-bb-art p{color:var(--muted);line-height:1.6}.hp-bb-heading{margin-top:2rem}.hp-bigbang-timeline{position:relative;display:grid;gap:.7rem;padding-left:1.1rem}.hp-bigbang-timeline:before{content:"";position:absolute;top:.6rem;bottom:.6rem;left:.25rem;width:2px;background:linear-gradient(var(--warning),var(--accent),var(--info),var(--purple))}.hp-bb-era{position:relative;display:grid;grid-template-columns:36px 1fr;gap:.7rem;width:100%;text-align:left;padding:.85rem;border:1px solid var(--hp-line);border-radius:15px;background:var(--hp-panel);color:var(--text);cursor:pointer;transition:transform .22s var(--hp-settle),border-color .22s ease,background .22s ease}.hp-bb-era:hover,.hp-bb-era.active{transform:translateX(4px);border-color:color-mix(in srgb,var(--accent) 55%,transparent);background:color-mix(in srgb,var(--accent) 8%,var(--hp-panel))}.hp-bb-index{display:grid;place-items:center;width:30px;height:30px;border-radius:50%;background:var(--bg-deep);border:1px solid var(--hp-line);font:.7rem ui-monospace,monospace;color:var(--accent)}.hp-bb-era.active .hp-bb-index{background:var(--accent);color:var(--bg-deep);box-shadow:0 0 0 5px var(--hp-soft)}.hp-bb-era .hp-evidence-badge{margin-bottom:.4rem}.hp-bb-era b,.hp-bb-era small{display:block}.hp-bb-era small{margin-top:.25rem;color:var(--muted);font-size:.76rem}.hp-bb-zoo-grid{margin-top:1.2rem}.hp-bb-zoo section{padding:.7rem 0;border-bottom:1px solid var(--hp-line)}.hp-bb-zoo section:last-child{border-bottom:0}.hp-bb-zoo h4{margin:0;color:var(--accent);font-size:.8rem;letter-spacing:.06em;text-transform:uppercase}.hp-bb-force-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:.6rem;margin-top:1rem}.hp-bb-force-grid span{padding:.75rem;border:1px solid var(--hp-line);border-radius:12px;background:var(--bg-deep);font-size:.75rem;color:var(--muted)}.hp-bb-force-grid b{display:block;margin-top:.25rem;color:var(--text);font-size:.82rem}.hp-bb-art{display:grid;grid-template-columns:1fr minmax(260px,.9fr);gap:1.2rem;align-items:center;margin-top:1.2rem;border-color:color-mix(in srgb,var(--purple) 45%,transparent)}.hp-bb-art figure{margin:0}.hp-bb-art img{display:block;width:100%;aspect-ratio:3/2;object-fit:cover;border:1px solid var(--hp-line);border-radius:14px;background:var(--bg-deep)}.hp-bb-art figcaption{margin-top:.55rem;color:var(--muted);font-size:.76rem;line-height:1.45}@media(max-width:760px){.hp-bb-visual-grid,.hp-bb-zoo-grid,.hp-bb-art{grid-template-columns:1fr}.hp-bb-canvas-card{overflow:auto}.hp-bb-canvas-card canvas{min-width:620px}.hp-bigbang-timeline{padding-left:.8rem}.hp-bb-era{grid-template-columns:31px 1fr}.hp-bb-force-grid{grid-template-columns:1fr}.hp-bb-art{padding:1rem}}

/* Immersive Big Bang learning layer — composited atmosphere, visual gallery, challenge, and bounded chat. */
#hp-view-bigbang{position:relative;isolation:isolate;overflow:hidden}#hp-view-bigbang:before,#hp-view-bigbang:after{content:"";position:absolute;z-index:-1;pointer-events:none;border-radius:50%;opacity:.22;filter:blur(18px);transform:translate3d(0,0,0);transition:opacity .55s ease,transform .7s var(--hp-settle),background .55s ease}#hp-view-bigbang:before{width:32rem;height:32rem;top:2rem;right:-13rem;background:radial-gradient(circle,color-mix(in srgb,var(--accent) 62%,transparent),transparent 64%);animation:hp-bb-nebula-a 16s ease-in-out infinite alternate}#hp-view-bigbang:after{width:25rem;height:25rem;top:28rem;left:-12rem;background:radial-gradient(circle,color-mix(in srgb,var(--purple) 56%,transparent),transparent 67%);animation:hp-bb-nebula-b 19s ease-in-out infinite alternate}#hp-view-bigbang[data-era="boundary"]:before{opacity:.08;transform:scale(.72)}#hp-view-bigbang[data-era="inflation"]:before{opacity:.44;transform:scale(1.18)}#hp-view-bigbang[data-era="quark"]:before{background:radial-gradient(circle,color-mix(in srgb,var(--warning) 65%,transparent),transparent 64%);opacity:.48}#hp-view-bigbang[data-era="recombination"]:after{background:radial-gradient(circle,color-mix(in srgb,var(--info) 66%,transparent),transparent 67%);opacity:.42}#hp-view-bigbang[data-era="dark-ages"]:before,#hp-view-bigbang[data-era="dark-ages"]:after{opacity:.1}#hp-view-bigbang[data-era="elements-us"]:after{opacity:.48;transform:scale(1.2)}@keyframes hp-bb-nebula-a{to{transform:translate3d(-18px,14px,0) scale(1.08)}}@keyframes hp-bb-nebula-b{to{transform:translate3d(20px,-16px,0) scale(.92)}}.hp-bb-gallery{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:1rem}.hp-bb-gallery-card{overflow:hidden;border:1px solid var(--hp-line);border-radius:18px;background:var(--hp-panel);transition:transform .35s var(--hp-spring),border-color .25s ease}.hp-bb-gallery-card:hover{transform:translateY(-4px);border-color:color-mix(in srgb,var(--accent) 55%,transparent)}.hp-bb-gallery-card img{display:block;width:100%;aspect-ratio:16/9;object-fit:cover;transition:transform .6s var(--hp-settle)}.hp-bb-gallery-card:hover img{transform:scale(1.045)}.hp-bb-gallery-card>div{padding:1rem}.hp-bb-gallery-card h3{margin:.55rem 0;font-size:1.08rem}.hp-bb-gallery-card p{margin:0;color:var(--muted);font-size:.82rem;line-height:1.5}.hp-bb-challenge{display:grid;gap:1rem;margin-top:1.2rem;border-color:color-mix(in srgb,var(--accent) 42%,transparent);background:linear-gradient(135deg,color-mix(in srgb,var(--accent) 9%,transparent),transparent 52%),var(--hp-panel)}.hp-bb-challenge h3{margin:.15rem 0;font-size:1.22rem}.hp-bb-challenge p{margin:.35rem 0;color:var(--muted);line-height:1.55}.hp-bb-challenge-options{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:.65rem}.hp-bb-choice{min-height:66px;display:flex;align-items:flex-start;gap:.55rem;text-align:left;padding:.7rem;border:1px solid var(--hp-line);border-radius:13px;background:var(--bg-deep);color:var(--text);cursor:pointer;transition:transform .2s var(--hp-spring),border-color .2s ease,background .2s ease}.hp-bb-choice:hover{transform:translateY(-2px);border-color:var(--accent);background:var(--hp-soft)}.hp-bb-choice:disabled{cursor:default}.hp-bb-choice>span{display:grid;place-items:center;flex:0 0 22px;height:22px;border-radius:50%;background:color-mix(in srgb,var(--accent) 18%,transparent);color:var(--accent);font-size:.72rem;font-weight:900}.hp-bb-choice.correct{border-color:var(--green,var(--accent));background:color-mix(in srgb,var(--green,var(--accent)) 14%,transparent)}.hp-bb-choice.incorrect{border-color:var(--danger);background:color-mix(in srgb,var(--danger) 10%,transparent)}.hp-bb-challenge-feedback{min-height:1.5rem;padding:.65rem .75rem;border-radius:10px;background:var(--bg-deep)}.hp-bb-challenge-feedback.correct{border-left:3px solid var(--green,var(--accent));color:var(--text)}.hp-bb-challenge-feedback.incorrect{border-left:3px solid var(--warning);color:var(--text)}.hp-bb-hypatia-fab{position:fixed;z-index:46;right:1rem;bottom:1rem;display:inline-flex;align-items:center;gap:.55rem;min-height:48px;padding:.4rem .75rem .4rem .4rem;border:1px solid color-mix(in srgb,var(--accent) 55%,transparent);border-radius:999px;background:color-mix(in srgb,var(--bg-card) 90%,transparent);color:var(--text);box-shadow:0 12px 32px color-mix(in srgb,var(--bg-deep) 58%,transparent);cursor:pointer;backdrop-filter:blur(14px);transition:transform .25s var(--hp-spring),border-color .25s ease}.hp-bb-hypatia-fab:hover{transform:translateY(-3px);border-color:var(--accent)}.hp-bb-hypatia-fab img{width:36px;height:36px;border-radius:50%;border:1px solid var(--accent)}.hp-bb-hypatia-fab span{font-size:.8rem;font-weight:800}.hp-bb-chat{position:fixed;z-index:60;right:1rem;bottom:1rem;width:min(430px,calc(100vw - 2rem));max-height:min(720px,calc(100dvh - 2rem));display:flex;flex-direction:column;gap:.75rem;padding:1rem;border:1px solid color-mix(in srgb,var(--accent) 45%,transparent);border-radius:20px;background:color-mix(in srgb,var(--bg-card) 94%,transparent);box-shadow:0 24px 70px color-mix(in srgb,var(--bg-deep) 62%,transparent);backdrop-filter:blur(18px);animation:hp-tutor-in .35s var(--hp-spring)}.hp-bb-chat[hidden]{display:none}.hp-bb-chat header{display:flex;justify-content:space-between;align-items:flex-start}.hp-bb-chat h3{margin:0}.hp-bb-chat-context{margin:0;padding:.65rem .75rem;border-left:3px solid var(--accent);border-radius:0 10px 10px 0;background:var(--hp-soft);font-size:.78rem;color:var(--muted)}.hp-bb-chat-messages{min-height:130px;max-height:260px;overflow:auto;display:grid;gap:.55rem}.hp-bb-chat-messages p{margin:0;padding:.65rem .75rem;border-radius:11px;background:var(--bg-surface);color:var(--muted);line-height:1.5}.hp-bb-chat-messages .hp-bb-chat-user{border-left:3px solid var(--info);color:var(--text)}.hp-bb-chat-messages .hp-bb-chat-hypatia{border-left:3px solid var(--accent);color:var(--text)}.hp-bb-chat-chips{display:flex;gap:.45rem;overflow:auto}.hp-bb-chat-chips button{min-height:38px;flex:0 0 auto;padding:.4rem .6rem;border:1px solid var(--hp-line);border-radius:999px;background:var(--bg-deep);color:var(--muted);font-size:.73rem;cursor:pointer}.hp-bb-chat-chips button:hover{color:var(--text);border-color:var(--accent)}.hp-bb-chat form{display:grid;gap:.55rem}.hp-bb-chat textarea{min-height:70px;resize:vertical;border:1px solid var(--hp-line);border-radius:12px;padding:.65rem;background:var(--input-bg);color:var(--text);font:inherit}@media(max-width:760px){.hp-bb-gallery{grid-template-columns:1fr}.hp-bb-challenge-options{grid-template-columns:1fr}.hp-bb-hypatia-fab{bottom:calc(.75rem + env(safe-area-inset-bottom,0px));right:.6rem}.hp-bb-chat{right:.5rem;bottom:calc(.5rem + env(safe-area-inset-bottom,0px));width:calc(100vw - 1rem)}}@media(prefers-reduced-motion:reduce){#hp-view-bigbang:before,#hp-view-bigbang:after,.hp-bb-gallery-card,.hp-bb-gallery-card img{animation:none!important;transition-duration:.01ms!important}}