:root,[data-theme=candy]{--bg:#fff7e6;--bg-alt:#ffe8f0;--ink:#2d2a32;--red:#ff6b6b;--teal:#4ecdc4;--yellow:#ffe066;--orange:#ffb84d;--purple:#b388ff;--blue:#5ac8fa;--white:#ffffff;--radius:20px;--border:3px solid var(--ink);--card-bg:var(--white);--card-shadow:0 6px 0 var(--orange),0 18px 30px rgba(255,145,60,0.18),inset 0 2px 0 rgba(255,255,255,0.65);--card-hover-shadow:0 12px 0 var(--orange),0 30px 46px rgba(255,145,60,0.26),inset 0 2px 0 rgba(255,255,255,0.65);--btn-shadow:0 4px 0 var(--ink),0 10px 18px rgba(45,42,50,0.16);--nav-bg:var(--white);--gradient-hero:linear-gradient(135deg,var(--bg),var(--bg-alt))}[data-theme=tech]{--bg:#0f0c29;--bg-alt:#1a1640;--ink:#e8e4f0;--red:#ff4d6a;--teal:#00f5a0;--yellow:#f0e14a;--orange:#ff8c42;--purple:#c084fc;--blue:#00d9f5;--white:rgba(255,255,255,0.06);--radius:20px;--border:2px solid rgba(255,255,255,0.15);--card-bg:rgba(255,255,255,0.05);--card-shadow:0 12px 36px rgba(0,0,0,0.5),0 0 24px rgba(0,245,160,0.07),inset 0 1px 0 rgba(255,255,255,0.12),inset 0 -14px 26px rgba(0,0,0,0.22);--card-hover-shadow:0 22px 54px rgba(0,0,0,0.55),0 0 44px rgba(0,245,160,0.2),inset 0 1px 0 rgba(255,255,255,0.18),inset 0 -14px 26px rgba(0,0,0,0.18);--btn-shadow:0 4px 16px rgba(0,245,160,0.25),0 10px 28px rgba(0,0,0,0.35);--nav-bg:rgba(15,12,41,0.92);--gradient-hero:linear-gradient(135deg,#0f0c29,#302b63,#1a1640)}*{box-sizing:border-box;margin:0;padding:0}body,html{background:var(--gradient-hero);min-height:100vh;color:var(--ink);font-family:PingFang SC,Microsoft YaHei,Segoe UI,system-ui,sans-serif;transition:background .35s ease,color .35s ease}a{color:inherit;text-decoration:none}button{font-family:inherit}.container{max-width:1080px;margin:0 auto;padding:24px 20px 80px}.candy-card{background:var(--card-bg);border:var(--border);border-radius:var(--radius);box-shadow:var(--card-shadow);transition:transform .15s ease,box-shadow .15s ease,background .35s ease}.candy-card.clickable{cursor:pointer}.candy-card.clickable:hover{transform:translateY(-4px);box-shadow:var(--card-hover-shadow)}.btn{display:inline-flex;align-items:center;justify-content:center;gap:6px;border:var(--border);border-radius:14px;padding:10px 22px;font-size:15px;font-weight:800;cursor:pointer;background:var(--yellow);color:#2d2a32;box-shadow:var(--btn-shadow);transition:transform .1s ease,box-shadow .1s ease;-webkit-user-select:none;-moz-user-select:none;user-select:none}.btn:hover{transform:translateY(-2px);box-shadow:0 7px 0 var(--ink),0 16px 26px rgba(45,42,50,.22)}.btn:active{transform:translateY(2px);box-shadow:0 1px 0 var(--ink),inset 0 3px 6px rgba(0,0,0,.2)}.btn:disabled{opacity:.5;cursor:not-allowed;transform:none}.btn.red{background:var(--red);color:#fff}.btn.teal{background:var(--teal);color:#fff}.btn.purple{background:var(--purple);color:#fff}.btn.ghost{background:var(--white)}.btn.small{padding:6px 14px;font-size:13px;border-width:2px;border-radius:10px;box-shadow:0 3px 0 var(--ink)}.input{border:var(--border);border-radius:14px;padding:12px 16px;font-size:15px;width:100%;background:var(--white);color:var(--ink);outline:none}.input:focus{box-shadow:0 0 0 4px rgba(255,184,77,.4)}.tag{display:inline-block;border-radius:99px;padding:3px 12px;font-size:12px;font-weight:700;color:#fff;background:var(--teal)}.nav{position:-webkit-sticky;position:sticky;top:0;z-index:50;background:var(--nav-bg);border-bottom:var(--border);padding:12px 20px;transition:background .35s ease}.nav-inner{max-width:1080px;margin:0 auto;gap:18px}.nav-inner,.nav-logo{display:flex;align-items:center}.nav-logo{font-size:20px;font-weight:900;gap:8px}.nav-links{display:flex;gap:14px;font-weight:700;font-size:14px}.nav-links a:hover{color:var(--red)}.nav-right{margin-left:auto;display:flex;align-items:center;gap:10px}.stat-chip{display:inline-flex;align-items:center;gap:4px;border:2px solid var(--ink);border-radius:99px;padding:4px 12px;font-size:13px;font-weight:800;background:var(--yellow)}.stat-chip.fire{background:var(--red);color:#fff}.book-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));grid-gap:20px;gap:20px}.book-cover{height:120px;border-radius:16px 16px 0 0;display:flex;align-items:center;justify-content:center;font-size:52px;border-bottom:var(--border)}.book-body{padding:14px 16px 16px}.tabs{display:flex;gap:10px;flex-wrap:wrap;margin:20px 0}.tab-btn{border:var(--border);border-radius:14px;background:var(--white);padding:10px 18px;font-size:15px;font-weight:800;cursor:pointer;box-shadow:0 4px 0 var(--ink);transition:all .12s ease}.tab-btn.active{background:var(--ink);color:var(--yellow);transform:translateY(2px);box-shadow:0 2px 0 var(--ink)}.study-card{max-width:640px;margin:0 auto;padding:34px 32px;min-height:320px;display:flex;flex-direction:column;animation:pop-in .3s ease}@keyframes pop-in{0%{opacity:0;transform:scale(.94) translateY(10px)}to{opacity:1;transform:scale(1) translateY(0)}}.progress-track{height:12px;border:2px solid var(--ink);border-radius:99px;background:var(--white);overflow:hidden}.progress-fill{height:100%;background:linear-gradient(90deg,var(--teal),var(--blue));border-radius:99px;transition:width .4s ease}.quote-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));grid-gap:18px;gap:18px}.quote-card{border:var(--border);border-radius:var(--radius);padding:22px 20px;color:#fff;font-size:16px;line-height:1.8;position:relative;min-height:130px;flex-direction:column;justify-content:space-between;box-shadow:0 6px 0 var(--ink)}.quiz-option,.quote-card{font-weight:700;display:flex}.quiz-option{align-items:center;gap:12px;border:var(--border);border-radius:14px;background:var(--white);padding:14px 16px;font-size:15px;cursor:pointer;transition:all .12s ease;width:100%;text-align:left}.quiz-option:hover:not(:disabled){background:var(--yellow);transform:translateX(4px)}.quiz-option.correct{background:var(--teal);color:#fff;animation:bounce .4s ease}.quiz-option.wrong{background:var(--red);color:#fff;animation:shake .4s ease}.quiz-option:disabled{cursor:default}@keyframes shake{0%,to{transform:translateX(0)}25%{transform:translateX(-8px)}50%{transform:translateX(8px)}75%{transform:translateX(-5px)}}@keyframes bounce{0%,to{transform:scale(1)}50%{transform:scale(1.04)}}.chat-box{display:flex;flex-direction:column;gap:12px;padding:20px;min-height:360px;max-height:480px;overflow-y:auto}.bubble{max-width:78%;border:2px solid var(--ink);border-radius:16px;padding:10px 14px;font-size:14px;line-height:1.7;white-space:pre-wrap;word-break:break-word}.bubble.user{align-self:flex-end;background:var(--yellow);border-bottom-right-radius:4px}.bubble.ai{align-self:flex-start;background:var(--white);border-bottom-left-radius:4px}@keyframes float-up{0%{opacity:1;transform:translateY(0) scale(1)}to{opacity:0;transform:translateY(-70px) scale(1.4)}}.float-points{top:46%;font-size:30px;font-weight:900;color:var(--red);text-shadow:2px 2px 0 var(--white);pointer-events:none;z-index:200;animation:float-up 1.1s ease forwards}.float-points,.toast{position:fixed;left:50%;transform:translateX(-50%)}.toast{top:74px;background:var(--ink);color:var(--yellow);border-radius:14px;border:2px solid var(--yellow);padding:12px 22px;font-weight:800;font-size:15px;z-index:300;animation:pop-in .25s ease;box-shadow:0 6px 20px rgba(0,0,0,.25)}@keyframes confetti-fall{0%{opacity:1;transform:translateY(-10vh) rotate(0deg)}to{opacity:.4;transform:translateY(105vh) rotate(2turn)}}.confetti{position:fixed;top:0;font-size:26px;pointer-events:none;z-index:400;animation:confetti-fall linear forwards}@keyframes chew{0%,to{transform:rotate(-8deg) scale(1)}50%{transform:rotate(8deg) scale(1.15)}}.chewing{display:inline-block;font-size:56px;animation:chew .8s ease-in-out infinite}.ring{transform:rotate(-90deg)}@keyframes bob{0%,to{transform:translateY(0)}50%{transform:translateY(-8px)}}.float-bob{animation:bob 2.6s ease-in-out infinite}@keyframes blink-eye{0%,92%,to{transform:scaleY(1)}95%{transform:scaleY(.1)}}.blink{animation:blink-eye 3.4s ease-in-out infinite;transform-origin:center;transform-box:fill-box}@keyframes twinkle-star{0%,to{opacity:1;transform:scale(1)}50%{opacity:.35;transform:scale(.8)}}.twinkle>*{animation:twinkle-star 1.8s ease-in-out infinite;transform-origin:center;transform-box:fill-box}.twinkle>:nth-child(2n){animation-delay:.6s}.twinkle>:nth-child(3n){animation-delay:1.1s}@keyframes chew-rock-kf{0%,to{transform:rotate(-3deg) translateY(0)}50%{transform:rotate(3deg) translateY(-4px)}}.chew-rock{animation:chew-rock-kf .7s ease-in-out infinite;transform-origin:center;transform-box:fill-box}.page-title{font-size:26px;font-weight:900;margin-bottom:6px}.muted{color:#7a7484;font-size:14px}.center{text-align:center}.spin{display:inline-block;animation:spin 1s linear infinite}@keyframes spin{to{transform:rotate(1turn)}}body:after,body:before{content:"";position:fixed;border-radius:50%;filter:blur(80px);pointer-events:none;z-index:-1}body:before{width:440px;height:440px;left:-130px;top:-90px;background:radial-gradient(circle,rgba(255,184,77,.38),transparent 70%)}body:after{width:540px;height:540px;right:-170px;bottom:-150px;background:radial-gradient(circle,rgba(255,143,171,.34),transparent 70%)}.book-grid{perspective:1400px}.candy-card.clickable:hover{transform:translateY(-7px) rotateX(2deg) scale(1.012)}.btn{background-image:linear-gradient(180deg,rgba(255,255,255,.5),rgba(255,255,255,0) 55%)}.book-cover{box-shadow:inset 0 14px 22px rgba(255,255,255,.35),inset 0 -18px 28px rgba(0,0,0,.14)}.quote-card{transition:transform .18s ease,box-shadow .18s ease}.quote-card:hover{transform:translateY(-6px) rotate(-.6deg);box-shadow:0 12px 0 var(--ink),0 24px 34px rgba(0,0,0,.2)}.tab-btn.active{box-shadow:0 2px 0 var(--ink),inset 0 3px 7px rgba(0,0,0,.35)}.nav{box-shadow:0 6px 22px rgba(45,42,50,.1)}.stat-chip{box-shadow:0 2px 0 rgba(45,42,50,.85),0 6px 12px rgba(45,42,50,.14)}.progress-fill{background-image:linear-gradient(180deg,rgba(255,255,255,.45),rgba(255,255,255,0) 60%),linear-gradient(90deg,var(--teal),var(--blue))}[data-theme=tech] body{background-attachment:fixed}[data-theme=tech] .candy-card,[data-theme=tech] .nav{backdrop-filter:blur(14px);-webkit-backdrop-filter:blur(14px)}[data-theme=tech] .btn{background:linear-gradient(135deg,var(--teal),var(--blue));color:#0f0c29;border-color:transparent}[data-theme=tech] .btn:hover{box-shadow:0 6px 24px rgba(0,245,160,.4)}[data-theme=tech] .btn:active{box-shadow:0 2px 8px rgba(0,245,160,.3)}[data-theme=tech] .btn.red{background:linear-gradient(135deg,var(--red),#ff8c42);color:#fff}[data-theme=tech] .btn.teal{background:linear-gradient(135deg,var(--teal),var(--blue));color:#0f0c29}[data-theme=tech] .btn.purple{background:linear-gradient(135deg,var(--purple),#818cf8);color:#fff}[data-theme=tech] .btn.ghost{background:rgba(255,255,255,.08);color:var(--ink);border:1px solid rgba(255,255,255,.2)}[data-theme=tech] .input{background:rgba(255,255,255,.06);border:1px solid rgba(255,255,255,.18);color:var(--ink)}[data-theme=tech] .input::placeholder{color:#8f89ad}[data-theme=tech] .input:focus{box-shadow:0 0 0 3px rgba(0,245,160,.25);border-color:var(--teal)}[data-theme=tech] .stat-chip{background:rgba(255,255,255,.08);color:var(--ink);border:1px solid rgba(255,255,255,.22)}[data-theme=tech] .stat-chip.fire{background:linear-gradient(135deg,var(--red),#ff8c42);color:#fff;border-color:transparent}[data-theme=tech] .tab-btn{background:rgba(255,255,255,.06);color:var(--ink);border:1px solid rgba(255,255,255,.16);box-shadow:none}[data-theme=tech] .tab-btn.active{background:linear-gradient(135deg,var(--teal),var(--blue));color:#0f0c29;box-shadow:0 4px 18px rgba(0,245,160,.35);transform:none}[data-theme=tech] .book-cover{border-bottom:1px solid rgba(255,255,255,.15);filter:saturate(.9)}[data-theme=tech] .quiz-option{background:rgba(255,255,255,.05);color:var(--ink);border:1px solid rgba(255,255,255,.16)}[data-theme=tech] .quiz-option:hover:not(:disabled){background:rgba(0,245,160,.12)}[data-theme=tech] .quiz-option.correct{background:linear-gradient(135deg,rgba(0,245,160,.85),rgba(0,217,245,.85));color:#0f0c29}[data-theme=tech] .quiz-option.wrong{background:linear-gradient(135deg,rgba(255,77,106,.85),rgba(255,140,66,.85));color:#fff}[data-theme=tech] .progress-track{background:rgba(255,255,255,.08);border:1px solid rgba(255,255,255,.2)}[data-theme=tech] .progress-fill{box-shadow:0 0 10px rgba(0,245,160,.6)}[data-theme=tech] .quote-card{box-shadow:0 8px 28px 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70%)}[data-theme=tech] .nav{box-shadow:0 10px 34px rgba(0,0,0,.45)}[data-theme=tech] .quote-card:hover{transform:translateY(-6px);box-shadow:0 18px 44px rgba(0,0,0,.5),0 0 34px rgba(0,245,160,.22)}[data-theme=tech] .tab-btn.active{box-shadow:0 4px 18px rgba(0,245,160,.35),inset 0 2px 5px rgba(0,0,0,.25)}[data-theme=tech] .stat-chip{box-shadow:0 4px 14px rgba(0,0,0,.35)}[data-theme=tech] .book-cover{box-shadow:inset 0 12px 22px rgba(255,255,255,.12),inset 0 -18px 30px rgba(0,0,0,.4)}