/* Shared structure, semantic theme tokens only. No answer-state rules. */
body[data-learning-theme]{--core-glow:#3a9eff24;--core-hero:#e6f2ff;--core-robot-glow:#80b9ff3b;--core-orbit:#73baff55}
body[data-learning-theme="dark"]{--core-glow:#4d96ff16;--core-hero:#142c4b;--core-robot-glow:#3c9bff30;--core-orbit:#7bbfff3b}
body[data-learning-theme]:has(.core-immersive) .main{background:radial-gradient(ellipse at 85% 0,var(--learn-glow),transparent 52%),radial-gradient(ellipse at 15% 90%,var(--core-glow),transparent 60%),var(--learn-bg)}
body[data-learning-theme]:has(.core-immersive) .main::before{background-image:radial-gradient(circle,var(--learn-star) .7px,transparent 1.5px),radial-gradient(circle,var(--learn-star) .6px,transparent 1.4px);background-size:137px 173px,227px 211px;background-position:31px 19px,80px 65px;opacity:.25}
body[data-learning-theme]:has(.core-immersive) .main::after{width:290px;height:290px;border-radius:50%;top:-170px;right:12%;background:radial-gradient(circle at 30% 35%,var(--core-hero),var(--learn-glow) 58%,var(--learn-bg));box-shadow:0 0 80px var(--core-glow);border:1px solid var(--core-orbit);transform:none}
.core-immersive{max-width:1440px;margin:auto;color:var(--learn-text)}
.core-breadcrumb{display:flex;flex-wrap:wrap;align-items:center;gap:10px;color:var(--learn-muted);font-size:12px;margin:4px 0 24px;line-height:1.8}
.core-breadcrumb strong{font-weight:600;color:var(--learn-text)}
.core-mini-planet{width:23px;height:23px;border-radius:50%;background:radial-gradient(circle at 30% 25%,#b3ecff,#3688df 50%,#164888);position:relative;margin-right:5px;flex:none;box-shadow:0 0 18px var(--core-glow)}
.core-mini-planet::after{content:"";position:absolute;width:34px;height:10px;border:1px solid var(--learn-accent);border-radius:50%;top:6px;left:-6px;transform:rotate(-27deg)}
.core-study-grid{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:22px;align-items:start}
body[data-learning-theme] .core-study-grid .quiz-main{max-width:none;padding:28px;min-width:0;border-radius:22px;box-shadow:var(--learn-shadow),inset 0 1px 0 var(--core-glow)}
.core-study-grid .quiz-head{margin-bottom:20px;padding-bottom:21px}
.core-study-grid .quiz-head h2{font-size:24px;line-height:1.4;margin:8px 0 4px;letter-spacing:.4px}
.core-eyebrow{font-size:11px;color:var(--learn-muted);letter-spacing:2px}
.core-question-type{border:1px solid var(--learn-line);background:var(--learn-raised);color:var(--learn-accent);font-size:12px;border-radius:9px;padding:7px 10px;white-space:nowrap}
.core-progress{display:flex;align-items:center;gap:13px;font-size:13px;margin-bottom:29px}
.core-progress b{font-size:20px;color:var(--learn-accent);font-weight:650}
.core-progress-track{height:5px;border-radius:6px;background:var(--learn-line);flex:1;overflow:hidden}
.core-progress-track i{display:block;height:100%;background:var(--learn-accent);border-radius:6px}
.core-progress small{font-size:11px;color:var(--learn-muted);white-space:nowrap}
.core-answer-instruction{font-size:12px;color:var(--learn-muted);margin:0 0 10px}
.core-study-grid .quiz-stem{font-size:19px;line-height:2;overflow-wrap:anywhere;margin-bottom:24px}
.core-study-grid .quiz-answer{margin:0}
body[data-learning-theme] .core-study-grid .quiz-answer .opt{display:flex;align-items:center;gap:12px;padding:18px 16px;min-height:70px;margin-bottom:12px;border-radius:14px}
.core-study-grid .opt .tx{font-size:17px;line-height:1.8;min-width:0;flex:1}
.core-study-grid .opt .mk{width:30px;height:30px;flex:none}
.core-check{width:19px;height:19px;border:1px solid var(--learn-line);border-radius:5px;display:grid;place-items:center;flex:none;font-size:13px}
.core-study-grid .sel .core-check{background:var(--learn-accent);border-color:var(--learn-accent);color:var(--learn-on-accent)}
.core-study-grid .quiz-actions{gap:10px;flex-wrap:wrap;padding-top:22px;margin-top:26px}
.core-study-grid .quiz-actions .btn{min-height:46px;padding:10px 18px;font-size:13px}
.core-study-grid [data-action=answer]{min-width:150px;box-shadow:0 5px 25px var(--core-glow)}
.core-study-grid .core-next{margin-left:auto}
.core-study-grid .quiz-main>p:last-child{font-size:12px;line-height:1.7}
.core-assistant{background:linear-gradient(160deg,var(--core-hero),var(--learn-surface) 48%);border:1px solid var(--learn-line);border-radius:22px;padding:21px;box-shadow:var(--learn-shadow);position:sticky;top:20px;min-width:0}
.core-assistant header{display:flex;align-items:center;gap:9px}
.core-ai-mark{font-size:24px;color:var(--learn-accent);text-shadow:0 0 18px var(--core-glow)}
.core-assistant h2{font-size:17px;margin:0;font-weight:650}
.core-assistant header p{font-size:11px;color:var(--learn-muted);margin:5px 0 0;line-height:1.5}
.core-lock-badge{margin-left:auto;font-size:10px;white-space:nowrap;color:var(--learn-muted);border:1px solid var(--learn-line);border-radius:20px;padding:4px 7px}
.core-assistant-welcome{text-align:center;padding:10px 0 19px}
.core-robot{width:126px;height:119px;color:var(--learn-accent);filter:drop-shadow(0 10px 20px var(--core-robot-glow));display:block;margin:0 auto}
.core-assistant-welcome p{font-size:13px;line-height:1.8;margin:0}
.core-assistant-welcome p span{font-size:11px;color:var(--learn-muted)}
.core-lock-card{background:var(--learn-surface);border:1px solid var(--learn-line);border-radius:16px;text-align:center;padding:17px 14px}
.core-lock-icon{display:grid;place-items:center;width:38px;height:38px;margin:0 auto 10px;background:var(--learn-selected);border-radius:12px;color:var(--learn-accent)}
.core-lock-card h3{font-size:14px;margin:0 0 9px;font-weight:600}
.core-lock-card p{font-size:12px;line-height:1.9;color:var(--learn-muted);margin:0 0 13px}
.core-lock-card button{min-height:40px;width:100%;font-size:12px}
.core-ai-capabilities h3{font-size:12px;margin:21px 0 16px;color:var(--learn-muted);font-weight:500}
.core-ai-capabilities ul{padding:0;margin:0;list-style:none}
.core-ai-capabilities li{display:flex;gap:11px;align-items:start;margin:0 0 17px}
.core-ai-capabilities li>span{width:30px;height:30px;border-radius:9px;background:var(--learn-selected);color:var(--learn-accent);display:grid;place-items:center;flex:none}
.core-ai-capabilities b{font-size:12px;font-weight:500;display:block;line-height:1.5}
.core-ai-capabilities small{font-size:10px;color:var(--learn-muted);line-height:1.7;display:block;margin-top:3px}
.core-assistant footer{font-size:10px;color:var(--learn-muted);border-top:1px solid var(--learn-line);padding-top:15px;line-height:1.7}
.core-explore-footer{text-align:center;color:var(--learn-muted);font-size:11px;letter-spacing:1px;margin:24px 0}
body[data-learning-theme] .core-selection-lock{opacity:1;background:var(--learn-raised);color:var(--learn-text);border:1px solid var(--learn-line);font-size:12px;cursor:default}
@media(min-width:1500px){.core-study-grid{grid-template-columns:minmax(0,1fr) 340px;gap:26px}.core-assistant{padding:25px}.core-robot{width:145px;height:136px}}
@media(max-width:1150px){.core-study-grid{grid-template-columns:minmax(0,1fr)}.core-assistant{position:static;display:grid;grid-template-columns:1fr 1fr;gap:16px 22px}.core-assistant header,.core-assistant footer{grid-column:1/-1}.core-assistant-welcome{display:none}.core-ai-capabilities h3{margin-top:0}.core-lock-card{align-self:start}.core-study-grid .quiz-main{width:100%}}
@media(max-width:760px){.core-assistant{display:block}.core-lock-card{margin-top:18px}.core-ai-capabilities{margin-top:20px}.core-study-grid .core-next{margin-left:0}}
/* Unified learning components and cinematic route artwork (shared original assets). */
body[data-learning-theme]{--study-overlay:linear-gradient(110deg,#eaf4ffed,#e3f0ffc4 60%,#c9e4ff85);--study-card:#fffffff5;--study-ai:#f5faffed;--study-glass-line:#c7dcf3;--study-depth:0 18px 50px #25558518;--study-wrong:#ad2945;--study-good:#167459}
body[data-learning-theme="dark"]{--study-overlay:linear-gradient(110deg,#030d2180,#07132c24 70%,#08122b33);--study-card:#0c1b30f5;--study-ai:#0f2440ed;--study-glass-line:#48709999;--study-depth:0 18px 55px #0007,inset 0 1px 0 #adcfff16;--study-wrong:#ffb6c6;--study-good:#8febd0}
body[data-learning-theme]:has(.study-workspace) .shell .main{background:var(--study-overlay),url('/assets/route-space.png') center top/cover fixed;isolation:isolate;padding-top:30px;min-height:100vh}
body[data-learning-theme]:has(.study-workspace) .main::before,body[data-learning-theme]:has(.study-workspace) .main::after{display:none}
body[data-learning-theme]:has(.study-workspace) .side{background:linear-gradient(#07172ceb,#0e2c4acc),url('/assets/route-space.png') left bottom/auto 100%;border-right:1px solid var(--study-glass-line)}
.study-workspace .core-breadcrumb{position:relative;z-index:1;margin-bottom:24px;padding:11px 14px;background:var(--study-card);border:1px solid var(--study-glass-line);border-radius:12px;width:fit-content;max-width:100%;box-shadow:var(--study-depth);padding-right:20px}
@keyframes study-orbit{to{transform:translate(-28px,-17px) rotate(20deg)}}
body[data-learning-theme] .study-workspace .quiz-main,body[data-learning-theme] .study-workspace .core-assistant{background:var(--study-card);border-color:var(--study-glass-line);box-shadow:var(--study-depth)}
.study-workspace .core-study-grid{grid-template-columns:minmax(0,1fr) 330px;gap:22px}
.study-workspace .core-assistant{background:var(--study-ai)!important;backdrop-filter:blur(18px)}
.study-status-pill{font-size:11px;border:1px solid var(--learn-line);padding:7px 10px;border-radius:8px;color:var(--learn-muted);white-space:nowrap}
.study-status-pill.pending{color:var(--learn-accent);background:var(--learn-selected)}
.study-status-pill.wrong{color:var(--study-wrong);background:var(--learn-error-bg)}
.study-status-pill.correct{color:var(--study-good);background:var(--learn-success-bg)}
body[data-learning-theme] .study-workspace .opt:disabled{opacity:1;cursor:default}
body[data-learning-theme] .study-workspace .opt.study-option-wrong{border-color:var(--study-wrong);background:var(--learn-error-bg)}
body[data-learning-theme] .study-workspace .opt.study-option-correct{border-color:var(--study-good);background:var(--learn-success-bg)}
.study-option-note{font-size:11px;line-height:1.7;color:var(--learn-muted);flex:none;max-width:105px;text-align:right}
.study-option-wrong .study-option-note{color:var(--study-wrong)}.study-option-correct .study-option-note{color:var(--study-good)}
.study-answer-compare{padding:14px 0;color:var(--learn-muted);font-size:13px;white-space:pre-wrap}
.study-feedback{display:flex;align-items:center;gap:16px;padding:23px 20px;border:1px solid var(--learn-line);border-radius:16px;margin:20px 0;background:var(--learn-raised)}
.study-feedback.wrong{background:linear-gradient(110deg,var(--learn-error-bg),var(--learn-raised));border-color:var(--study-wrong)}
.study-feedback.correct{background:var(--learn-success-bg)}.study-feedback.pending{background:var(--learn-selected)}
.study-feedback h3{font-size:19px;margin:0 0 7px;letter-spacing:.5px}.study-feedback.wrong h3{color:var(--study-wrong)}
.study-feedback p{font-size:12px;line-height:1.9;margin:0;color:var(--learn-muted)}.study-feedback small{font-size:11px;display:block;margin-top:6px;color:var(--learn-muted)}
.study-result-icon{font-size:26px;width:43px;height:43px;display:grid;place-items:center;flex:none;border-radius:50%;background:var(--learn-selected);color:var(--learn-accent)}
.wrong .study-result-icon{color:var(--study-wrong);background:var(--learn-error-bg)}
.study-my-answer,.study-analysis{border-top:1px solid var(--learn-line);padding-top:23px;margin-top:24px}
.study-my-answer h3,.study-analysis h3{font-size:16px;margin:0 0 15px;border-left:3px solid var(--learn-accent);padding-left:10px}
.study-my-answer>small{display:block;margin-bottom:12px;font-size:11px}
.submitted-text{white-space:pre-wrap;background:var(--learn-raised);border:1px solid var(--learn-line);border-radius:12px;padding:17px;line-height:1.9;font-size:15px;overflow-wrap:anywhere}
.study-answer-images{display:grid;gap:12px;margin-top:15px}.study-answer-images figure{margin:0;border:1px solid var(--learn-line);border-radius:12px;overflow:hidden;background:var(--learn-paper)}
.study-answer-images img{display:block;max-height:320px;width:100%;object-fit:contain}.study-answer-images button{display:block;width:100%;padding:12px;background:var(--learn-raised);color:var(--learn-text);border:0;font:inherit;font-size:12px;cursor:pointer}
.study-question-figure{margin:0 0 24px;padding:18px;background:white;border:1px solid var(--learn-line);border-radius:14px;text-align:center;color:#496384}
.study-question-figure img{max-width:100%;max-height:290px;object-fit:contain;display:block;margin:auto}.study-question-figure figcaption{font-size:11px;margin-top:10px}
.study-standard{padding:15px;background:var(--learn-selected);border-radius:10px;margin:15px 0;line-height:1.9;font-size:14px;white-space:pre-wrap}
.study-analysis h4{font-size:15px;margin:20px 0 12px}.study-analysis .analysis{font-size:15px;line-height:2;white-space:pre-wrap;overflow-wrap:anywhere}
.analysis-step{padding:16px;border:1px solid var(--learn-line);border-radius:12px;margin-bottom:12px}.analysis-step summary{font-size:13px;font-weight:600;cursor:pointer;margin-bottom:12px;color:var(--learn-accent)}
.study-selection-tip{font-size:11px;color:var(--learn-muted);margin-top:18px}
body[data-learning-theme] .study-ai{background:var(--study-ai);border:1px solid var(--study-glass-line);box-shadow:var(--study-depth);padding:20px;position:sticky;inset:auto;top:18px;width:auto;max-height:calc(100dvh - 36px);border-radius:22px;backdrop-filter:blur(18px);gap:12px;min-width:0}
.study-ai-heading{display:flex;align-items:center;gap:8px;flex:none}.study-ai-heading .core-robot{width:57px;height:55px;margin:0}.study-ai-heading h3{font-size:17px!important;border:0!important;padding:0!important;margin:0 0 6px}.study-ai-heading p{font-size:11px;line-height:1.6;color:var(--learn-muted);margin:0}
.study-ai-tabs{display:flex;gap:5px;background:var(--learn-raised);padding:4px;border-radius:10px;flex:none}
.study-ai-tabs button{flex:1;background:none;border:0;border-radius:7px;color:var(--learn-muted);padding:10px 5px;font:inherit;font-size:12px;cursor:pointer}
.study-ai-tabs button[aria-pressed=true]{background:var(--learn-surface);color:var(--learn-accent);box-shadow:var(--learn-shadow)}
.study-ai .quote-chip{flex:none;border-radius:10px;max-height:145px;font-size:12px;line-height:1.8}.study-ai .quote-chip b{font-size:11px;color:var(--learn-accent)}.study-ai .quote-chip>div{white-space:pre-wrap}.study-ai .quote-chip button{font-size:10px;padding:4px 8px;margin-top:5px}
.study-ai .ai-messages{min-height:110px;max-height:420px;overflow:auto;scrollbar-width:thin;overscroll-behavior:contain}
.study-ai .ai-message{font-size:13px;margin-bottom:12px;padding:14px;line-height:1.95;border:1px solid var(--learn-line)}
.study-ai .ai-message small{font-size:10px;display:block;color:var(--learn-muted);margin-bottom:6px}.study-ai .ai-message blockquote{font-size:11px;padding-left:10px;border-left:2px solid var(--learn-accent);margin:10px 0 0;color:var(--learn-muted)}
.study-ai-empty{text-align:center;padding:22px 10px;color:var(--learn-muted)}.study-ai-empty>span{font-size:33px;color:var(--learn-accent)}.study-ai-empty h4{font-size:14px;color:var(--learn-text);font-weight:500;margin:15px 0}.study-ai-empty p{font-size:12px;line-height:1.9}
.study-followups{display:flex;flex-wrap:wrap;gap:7px;flex:none}.study-followups>span{width:100%;font-size:11px;color:var(--learn-muted)}
.study-followups button{border:1px solid var(--learn-line);background:var(--learn-raised);color:var(--learn-text);border-radius:18px;font-size:11px;padding:8px 11px;cursor:pointer}
.study-ai .ai-compose{flex:none}.study-ai .ai-compose label{font-size:11px;color:var(--learn-muted)}.study-ai .ai-compose textarea{min-height:66px;margin-top:6px;resize:vertical;max-height:160px}.study-ai .quiz-actions{margin:8px 0 0;padding:0;border:0;justify-content:flex-end}.study-ai .quiz-actions button{min-height:36px;font-size:12px}.study-ai #ai-status{font-size:10px;line-height:1.6;margin:0;flex:none}
body[data-learning-theme] .study-quote-menu{background:var(--learn-surface);color:var(--learn-text);border:1px solid var(--learn-line);padding:5px;border-radius:12px;display:flex;gap:3px;box-shadow:var(--study-depth)}
.study-quote-menu button{background:none;border:0;color:inherit;font:inherit;font-size:12px;min-height:36px;padding:7px 10px;cursor:pointer}.study-quote-menu button:hover{background:var(--learn-selected);border-radius:8px}
@media(max-width:1250px){.study-workspace .core-study-grid{grid-template-columns:minmax(0,1fr) 300px;gap:16px}body[data-learning-theme] .study-workspace .quiz-main{padding:23px}.study-workspace .core-study-grid .quiz-stem{font-size:17px}}
@media(max-width:1100px){.study-workspace .core-study-grid{grid-template-columns:minmax(0,1fr)}body[data-learning-theme] .study-ai{position:static;max-height:none;display:flex}.study-ai .ai-messages{max-height:400px;min-height:120px}.study-space-art{opacity:.65}.study-workspace .core-breadcrumb{margin-top:15px}}
/* Keep geometric diagrams and saved sheets readable without dominating the page. */
body[data-learning-theme] .study-question-figure .quiz-image{max-height:300px;width:auto;max-width:100%;object-fit:contain;margin:auto}
body[data-learning-theme] .study-answer-images img{max-height:220px;object-fit:contain}
.study-ai blockquote{margin:12px 0 0;padding-left:10px;border-left:2px solid var(--learn-accent);white-space:normal}