/* Shared appearance tokens mirror SplitStyle in the native prototype. */
:root,.research-page{--blue:#284de5;--paper:#f2f5fa;--ink:#152345;--muted:#64708a;--card:#fff;--line:#e2e7f1;--lilac:#e7eafe;--mint:#e1f3ed;--action-blue:#264de8;--scene:#edf0fa;--orbit:#b6c4ef;--orbit-mid:#c9d3f1;--orbit-outer:#dce3f7}
html[data-theme="dark"],html[data-theme="dark"] .research-page{--paper:#101625;--ink:#f2f5ff;--muted:#abb7d0;--blue:#a3b7ff;--card:#1b2539;--line:#344057;--lilac:#303b61;--mint:#203e3b;--scene:#182238;--orbit:#3f507b;--orbit-mid:#2f3e62;--orbit-outer:#26334f}
body{isolation:isolate}
body::before{content:"";position:fixed;inset:-8%;z-index:-1;pointer-events:none;background:radial-gradient(ellipse at 4% 15%,#426eff26,transparent 45%),radial-gradient(ellipse at 100% 48%,#9e75f526,transparent 45%),radial-gradient(ellipse at 8% 95%,#33b8e326,transparent 45%);animation:ambient-drift 28s ease-in-out infinite alternate}
@keyframes ambient-drift{from{transform:translate3d(-1%,-1%,0)}to{transform:translate3d(2%,2%,0)}}
.header-actions{display:flex;align-items:center;gap:16px;flex-shrink:0}.theme-toggle{display:flex;align-items:center;justify-content:center;gap:8px;min-height:44px;padding:8px 10px;border:1px solid var(--line);border-radius:24px;background:var(--card);color:var(--muted);cursor:pointer;touch-action:manipulation}.theme-toggle svg{width:16px;height:16px;fill:none;stroke:currentColor;stroke-width:1.7;stroke-linecap:round;stroke-linejoin:round}.toggle-track{display:block;width:30px;height:18px;border-radius:20px;background:var(--line);padding:3px;transition:background .2s}.toggle-track>span{display:block;width:12px;height:12px;background:var(--blue);border-radius:50%;transition:transform .2s}.theme-toggle[aria-checked="true"] .toggle-track>span{transform:translateX(12px)}.theme-toggle[aria-checked="false"] .theme-sun,.theme-toggle[aria-checked="true"] .theme-moon{color:var(--blue)}.theme-toggle:hover{border-color:var(--blue)}.theme-toggle:focus-visible{outline:3px solid var(--blue);outline-offset:4px}
.soon-tag,.skip-link{background:var(--card)}.hero-description,.chapter-copy>p:not(.chapter-index){color:var(--muted)}.chapter-copy>p.feature-note{background:var(--lilac);border-color:var(--blue)}
.walkthrough-section,.about-section,.evidence-section,.landscape-section{background:var(--card)}.screen-scene{background:var(--scene)}.scene-orbit{border-color:var(--orbit);box-shadow:0 0 0 27px var(--scene),0 0 0 28px var(--orbit-mid),0 0 0 55px var(--scene),0 0 0 56px var(--orbit-outer)}
.path-panel,.research-invitation{background:var(--lilac)}.path-selector button{border-color:var(--line)}.path-selector button[aria-pressed="true"]{background:var(--action-blue);border-color:var(--action-blue);color:#fff}.primary-link,.closing,.track-motif,.hybrid-chart,.research-closing{background:var(--action-blue);color:#fff}.primary-link:hover{background:#1c3ab8}.walkthrough-enhanced .chapter.is-active .chapter-index>span{background:var(--action-blue);border-color:var(--action-blue)}
html[data-theme="dark"] .status-label{color:#a1dcca}html[data-theme="dark"] .testing-label{color:#f3c98a}html[data-theme="dark"] .future-label{color:var(--muted)}html[data-theme="dark"] .status-dot{background:#f3c98a}.number-divider{color:var(--muted)}
.research-nav{background:color-mix(in srgb,var(--paper) 94%,transparent)}.filter-buttons button{background:var(--card)}.filter-buttons button[aria-pressed="true"]{background:var(--action-blue);border-color:var(--action-blue)}.current-fit{background:var(--paper)}.research-closing .primary-link{background:#fff;color:#284de5}html[data-theme="dark"] .counterpoint p{color:#b9d9d0}html[data-theme="dark"] .hypothesis-label{background:#483d28;color:#eed8a0}html[data-theme="dark"] .race-story .hypothesis-label{background:#ffffff18;color:#dfe8ff}
html[data-theme="dark"] .screen-stack,html[data-theme="dark"] .hero-screen{border-color:#344057;box-shadow:0 22px 45px #0005}
@media(min-width:761px) and (max-width:1000px){.site-header{flex-wrap:wrap}.site-header nav{order:3;width:100%;justify-content:space-between;border-top:1px solid var(--line);padding-top:8px}.header-actions{margin-left:auto}.hero-art{overflow:clip}}
@media(max-width:760px){.header-actions{margin-left:auto;gap:10px}.walkthrough-enhanced .walkthrough-visual{background:var(--card)}.site-header nav{justify-content:space-between;gap:12px}}
@media(max-width:430px){.theme-toggle{gap:6px;padding-inline:9px}.theme-toggle svg{width:14px;height:14px}.header-actions{gap:8px}.soon-tag{padding:9px;font-size:9px}.site-header .brand-wordmark{width:83px}}
@media(prefers-reduced-motion:reduce){body::before{animation:none}.toggle-track,.toggle-track>span{transition:none}}
@media(prefers-reduced-transparency:reduce),(prefers-contrast:more){body::before{display:none}.research-nav{background:var(--paper);backdrop-filter:none}.theme-toggle{border-color:var(--ink)}.walkthrough-enhanced .chapter{opacity:1}}
@media(prefers-contrast:more){:root,.research-page{--muted:#364766;--line:#74829c}html[data-theme="dark"],html[data-theme="dark"] .research-page{--muted:#dae3f5;--line:#93a2bf}}
@media(forced-colors:active){body::before,.track-motif,.scene-orbit{display:none}.toggle-track{border:1px solid ButtonText;background:Canvas}.toggle-track>span{background:ButtonText}}
@media print{.header-actions{display:none}body::before{display:none}}