:root{--primary: #8e44ad;--primary-dark: #6c3483;--primary-light: #a569bd;--secondary: #e74c3c;--accent: #f39c12;--text-dark: #2c3e50;--text-light: #555;--bg-gradient: linear-gradient(135deg, #fdfbfd 0%, #f4ecf7 100%);--white: #ffffff;--card-bg: #ffffff;--box-bg: #f4f6f7;--header-bg: rgba(255, 255, 255, .95);--border-color: #eee;--success: #27ae60;--error: #c0392b;--shadow: 0 10px 30px rgba(0, 0, 0, .05);--accordion-header: #f8f9fa;--focus-ring: 2px solid var(--accent)}body.dark-mode{--primary: #9b59b6;--primary-dark: #8e44ad;--primary-light: #be93d4;--secondary: #e74c3c;--accent: #f39c12;--text-dark: #ecf0f1;--text-light: #bdc3c7;--bg-gradient: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);--white: #1f2937;--card-bg: #1f2937;--box-bg: #2c3e50;--header-bg: rgba(31, 41, 55, .95);--border-color: #374151;--shadow: 0 10px 30px rgba(0, 0, 0, .3);--accordion-header: #374151}*{margin:0;padding:0;box-sizing:border-box;font-family:Poppins,sans-serif;scroll-behavior:smooth}body{background:var(--bg-gradient);color:var(--text-dark);overflow-x:hidden;line-height:1.6;transition:background .3s,color .3s}:focus-visible{outline:var(--focus-ring);outline-offset:2px}.progress-container{position:fixed;top:0;left:0;width:100%;height:5px;background:#0000001a;z-index:2000}.progress-bar{height:5px;background:var(--secondary);width:0%;transition:width .1s}header{background:var(--header-bg);backdrop-filter:blur(12px);padding:.8rem 5%;display:flex;justify-content:space-between;align-items:center;box-shadow:0 4px 20px #0000000a;position:sticky;top:0;z-index:1000;transition:background 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var(--border-color);border-radius:5px;cursor:pointer;transition:.2s;display:inline-block;margin:5px}@keyframes fadeInUp{0%{opacity:0;transform:translateY(30px)}to{opacity:1;transform:translateY(0)}}@keyframes shake{0%,to{transform:translate(0)}25%{transform:translate(-5px)}75%{transform:translate(5px)}}@keyframes popIn{0%{transform:scale(.8);opacity:0}to{transform:scale(1);opacity:1}}.reveal{opacity:1;transform:none;transition:none}.reveal.active{opacity:1;transform:none}.shake{animation:shake .4s ease-in-out}.pop{animation:popIn .4s cubic-bezier(.175,.885,.32,1.275)}.sorter-container{display:flex;flex-direction:column;gap:15px;align-items:center}.statement-card{background:var(--card-bg);padding:15px;border-radius:8px;box-shadow:var(--shadow);font-weight:500;width:100%;max-width:500px;color:var(--text-dark);border:1px solid var(--border-color)}.sort-btn{padding:8px 20px;border:none;border-radius:50px;cursor:pointer;font-weight:600;transition:.2s;min-width:100px}.btn-axiom{background:#e8daef;color:#8e44ad}.btn-postulate{background:#fadbd8;color:#c0392b}.btn-axiom:hover{background:#d2b4de}.btn-postulate:hover{background:#f5b7b1}.accordion-item{border:1px solid var(--border-color);border-radius:8px;margin-bottom:10px;overflow:hidden}.accordion-header{background:var(--accordion-header);padding:15px;cursor:pointer;font-weight:600;display:flex;justify-content:space-between;align-items:center;transition:background .3s;color:var(--text-dark)}.accordion-header:hover{background:var(--border-color)}.accordion-body{border-top:1px solid var(--border-color);color:var(--text-dark);max-height:0;opacity:0;overflow:hidden;padding:0 15px;transition:max-height .3s ease-out,opacity .3s ease-out,padding .3s ease}.accordion-body.open{max-height:1000px;opacity:1;padding:15px}.table-container{width:100%;overflow:hidden;margin:20px 0}.styled-table{width:100%;border-collapse:collapse;font-size:.95em;background-color:var(--card-bg);border-radius:10px;overflow:hidden}.styled-table thead tr{background-color:var(--primary);color:#fff;text-align:left}.styled-table th,.styled-table td{padding:12px 15px;border-bottom:1px solid var(--border-color);color:var(--text-dark)}.styled-table tbody tr:last-of-type{border-bottom:2px solid var(--primary)}@media(max-width:768px){.styled-table thead{display:none}.styled-table,.styled-table tbody,.styled-table tr,.styled-table td{display:block;width:100%}.styled-table tr{margin-bottom:15px;border:1px solid var(--border-color);border-radius:10px;box-shadow:var(--shadow);background:var(--card-bg)}.styled-table td{padding-left:50%;text-align:right;position:relative;border-bottom:1px solid var(--border-color)}.styled-table td:last-child{border-bottom:none}.styled-table 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var(--border-color);font-size:.95rem}.result-row:last-child{border-bottom:none}.res-label{font-weight:600;color:var(--text-light)}.res-val{font-weight:700;color:var(--primary)}.shape-visual{width:150px;height:150px;margin:0 auto 15px;display:block}.switch-group{display:flex;justify-content:center;margin-bottom:15px;background:var(--card-bg);padding:5px;border-radius:50px;border:1px solid var(--border-color);width:fit-content;margin-left:auto;margin-right:auto}.switch-btn{padding:8px 20px;border:none;background:transparent;color:var(--text-light);cursor:pointer;border-radius:50px;font-weight:600;transition:.3s}.switch-btn.active{background:var(--primary);color:#fff}body.dark-mode ellipse{stroke:#ecf0f1}.carousel-container{position:relative;max-width:800px;margin:2rem auto;border-radius:20px;overflow:hidden;box-shadow:var(--shadow);background:var(--card-bg);border:1px solid rgba(0,0,0,.05)}.carousel-slide{display:none;padding:2rem;text-align:center;animation:fadeIn .5s ease-in-out}.carousel-img{max-width:300px;height:auto;margin-bottom:1.5rem;filter:drop-shadow(0 10px 15px rgba(0,0,0,.1))}.carousel-controls{display:flex;align-items:center;justify-content:center;gap:20px;padding:1rem;background:#00000005}.carousel-btn{background:var(--primary);color:#fff;border:none;width:40px;height:40px;border-radius:50%;cursor:pointer;transition:all .3s;display:flex;align-items:center;justify-content:center}.carousel-btn:hover{transform:scale(1.1);background:var(--primary-dark)}.carousel-dots{display:flex;gap:8px}.dot{width:10px;height:10px;border-radius:50%;background:#ddd;cursor:pointer;transition:.3s}.dot.active{background:var(--primary);width:25px;border-radius:10px}@keyframes fadeIn{0%{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}.tally-container{display:flex;flex-wrap:wrap;gap:15px;margin-top:15px;font-size:2rem;min-height:50px;align-items:center;font-family:Courier 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.3s;max-width:180px}.stat-card:hover{transform:translateY(-5px)}.stat-label{display:block;font-size:.85rem;color:var(--text-light);text-transform:uppercase;letter-spacing:1px;margin-bottom:.5rem}.stat-val{font-size:1.8rem;font-weight:700;color:var(--text-dark)}.graph-builder{display:flex;align-items:flex-end;gap:15px;height:250px;border-bottom:2px solid var(--text-light);border-left:2px solid var(--text-light);padding:20px;margin-top:20px;background:linear-gradient(to top,rgba(0,0,0,.03),transparent);border-radius:8px;transition:gap .5s ease}.histogram{gap:0!important}.graph-bar-container{flex:1;height:100%;display:flex;flex-direction:column;justify-content:flex-end;position:relative}.graph-bar{width:100%;background:var(--primary);border-radius:5px 5px 0 0;transition:height .5s cubic-bezier(.175,.885,.32,1.275),background .3s;position:relative;box-shadow:0 4px 6px #0000001a;min-height:1px;border:1px solid rgba(0,0,0,.1)}.histogram .graph-bar{border-radius:0;border-right:1px solid rgba(255,255,255,.5)}.graph-input{width:100%;text-align:center;border:none;background:transparent;font-weight:700;color:var(--text-dark);margin-bottom:8px;font-size:1.1rem}.graph-input:focus{outline:none;color:var(--accent)}.graph-label{margin-top:5px;font-size:.8rem;text-align:center}.flip-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(280px,1fr));gap:20px;margin:20px 0}.flip-card{background-color:transparent;height:200px;perspective:1000px;cursor:pointer}.flip-card-inner{position:relative;width:100%;height:100%;text-align:center;transition:transform .6s;transform-style:preserve-3d;box-shadow:var(--shadow);border-radius:15px}.flip-card.flipped .flip-card-inner{transform:rotateY(180deg)}.flip-card-front,.flip-card-back{position:absolute;width:100%;height:100%;-webkit-backface-visibility:hidden;backface-visibility:hidden;border-radius:15px;display:flex;flex-direction:column;justify-content:center;align-items:center;padding:20px;box-sizing:border-box}.flip-card-front{background:var(--card-bg);color:var(--text-dark);border:1px solid var(--border-color)}.flip-card-back{background-color:var(--primary);color:#fff;transform:rotateY(180deg)}.data-input{width:90%;padding:12px;border-radius:8px;border:1px solid var(--border-color);text-align:center;background:var(--card-bg);color:var(--text-dark);font-size:1rem;margin-bottom:15px}.cm-input{width:80px;padding:10px;border-radius:5px;border:1px solid var(--border-color);text-align:center;background:var(--card-bg);color:var(--text-dark)}.degree-game{display:flex;justify-content:center;gap:15px;margin-top:20px;flex-wrap:wrap}.graph-container{background:#fff;border:1px solid var(--border-color);border-radius:10px;padding:10px;margin:0 auto 20px;display:flex;flex-direction:column;align-items:center;justify-content:center}.coord-input-group{display:flex;justify-content:center;gap:10px;margin:15px 0;flex-wrap:wrap}.coord-input{padding:10px;border:1px solid #ccc;border-radius:5px;width:80px;text-align:center;font-size:1rem}.quad-result{margin-top:15px;font-weight:700;min-height:24px;font-size:1.1rem}.input-group{display:flex;justify-content:center;gap:10px;margin:15px 0;flex-wrap:wrap}.small-input{padding:8px;border:1px solid #ccc;border-radius:5px;width:70px;text-align:center}.quiz-question{background:var(--card-bg);padding:15px;border-radius:10px;border:1px solid var(--border-color);margin-bottom:20px}.quiz-question p{margin-bottom:10px;font-weight:600}.definition-item{background:var(--box-bg);padding:10px;margin:5px 0;border-left:3px solid var(--primary);color:var(--text-dark);border-radius:4px}body.dark-mode line{stroke:#ecf0f1}body.dark-mode text{fill:#ecf0f1}body.dark-mode line[stroke="#e74c3c"]{stroke:#e74c3c!important}body.dark-mode text[fill=blue]{fill:#5dade2}body.dark-mode path[stroke=blue]{stroke:#5dade2}body.dark-mode text[fill="#555"]{fill:#bdc3c7}.angle-display{font-size:2.5rem;font-weight:800;color:var(--accent);margin:15px 0}.clickable-angle{cursor:pointer;transition:fill .3s}.clickable-angle:hover{fill:var(--accent);fill-opacity:.5}body.dark-mode .clickable-angle{fill:#ecf0f1;fill-opacity:.1}.tabs-container{width:100%;margin-top:20px}.tabs-header{display:flex;overflow-x:auto;border-bottom:2px solid var(--border-color);gap:5px;padding-bottom:5px}.tab-btn{padding:10px 20px;background:var(--box-bg);border:none;border-radius:5px 5px 0 0;cursor:pointer;font-weight:600;color:var(--text-light);transition:.3s;white-space:nowrap}.tab-btn.active{background:var(--primary);color:#fff}.tab-content{display:none;padding:20px;background:var(--box-bg);border-radius:0 0 10px 10px;animation:fadeIn 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var(--primary)}.angle-input{width:70px;padding:10px;border-radius:5px;border:1px solid var(--border-color);text-align:center;background:var(--card-bg);color:var(--text-dark)}.clickable-point{cursor:pointer;transition:r .3s}.clickable-point:hover{r:8;fill:var(--accent)}body.dark-mode line[stroke="#3498db"]{stroke:#5dade2!important}.graph-canvas-container{width:100%;max-width:450px;height:350px;margin:0 auto 20px;background:var(--card-bg);border:1px solid var(--border-color);border-radius:15px}.anatomy-container{width:100%;max-width:400px;margin:0 auto;text-align:center}.anatomy-part{cursor:pointer;transition:all .3s}.anatomy-part:hover{opacity:.7}body.dark-mode circle[fill=none]{stroke:#ecf0f1}body.dark-mode path{stroke:#ecf0f1}body.dark-mode text[fill=red]{fill:#e74c3c}.calc-btn{padding:12px 30px;background:var(--success);color:#fff;border:none;border-radius:8px;cursor:pointer;font-weight:700;font-size:1rem;transition:transform 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cubic-bezier(.4,0,.2,1);min-width:120px;text-align:center;position:relative;overflow:hidden}.choice-btn:after{content:"";position:absolute;inset:0;background:var(--primary);opacity:0;transition:opacity .25s;z-index:0;border-radius:50px}.choice-btn:hover:not(:disabled){transform:translateY(-2px);box-shadow:0 6px 20px #8e44ad33;background:var(--primary);color:#fff}.choice-btn:active:not(:disabled){transform:scale(.97)}.choice-btn:disabled{opacity:.65;cursor:default}.choice-btn.correct{background:linear-gradient(135deg,#27ae60,#2ecc71)!important;border-color:#27ae60!important;color:#fff!important;box-shadow:0 4px 16px #27ae604d;animation:correctPulse .5s ease}.choice-btn.wrong{background:linear-gradient(135deg,#e74c3c,#c0392b)!important;border-color:#e74c3c!important;color:#fff!important;box-shadow:0 4px 16px #e74c3c4d;animation:shake .4s ease}@keyframes correctPulse{0%{transform:scale(1)}50%{transform:scale(1.06)}to{transform:scale(1)}}@keyframes shake{0%,to{transform:translate(0)}20%{transform:translate(-6px)}40%{transform:translate(6px)}60%{transform:translate(-4px)}80%{transform:translate(4px)}}.coach-feedback{background:var(--box-bg);border-left:4px solid var(--accent);padding:12px 16px;border-radius:0 10px 10px 0;margin:14px 0;font-size:.93rem;color:var(--text-dark);transition:all .3s ease;min-height:44px;display:flex;align-items:center}.coach-feedback.good{background:#27ae601a;border-left-color:#27ae60;color:#1e8449}.coach-feedback.warn{background:#f39c121a;border-left-color:#f39c12;color:#b7950b}body.dark-mode .coach-feedback.good{background:#27ae6026;color:#58d68d}body.dark-mode .coach-feedback.warn{background:#f39c1226;color:#f9e79f}.inline-input{padding:10px 14px;border:2px solid var(--border-color);border-radius:10px;background:var(--card-bg);color:var(--text-dark);font-size:.95rem;font-family:inherit;transition:border-color .3s,box-shadow .3s;width:100%;max-width:280px;margin:6px 0}.inline-input:focus{border-color:var(--primary);box-shadow:0 0 0 3px #8e44ad1f;outline:none}.mini-select{padding:10px 36px 10px 14px;border:2px solid var(--border-color);border-radius:10px;background:var(--card-bg);color:var(--text-dark);font-size:.95rem;font-family:inherit;cursor:pointer;transition:border-color .3s;appearance:none;-webkit-appearance:none;background-image:url("data:image/svg+xml,%3Csvg width='12' height='8' viewBox='0 0 12 8' xmlns='http://www.w3.org/2000/svg'%3E%3Cpath d='M1 1l5 5 5-5' stroke='%238e44ad' stroke-width='2' fill='none'/%3E%3C/svg%3E");background-repeat:no-repeat;background-position:right 12px center;margin:6px 0}.mini-select:focus{border-color:var(--primary);outline:none}.rule-preview{background:#8e44ad0f;border:1px solid rgba(142,68,173,.15);border-radius:10px;padding:10px 16px;margin:10px 0;font-size:.95rem;color:var(--primary-dark);text-align:center}body.dark-mode .rule-preview{background:#9b59b61f;border-color:#9b59b640;color:var(--primary-light)}.reveal-btn{padding:8px 20px;border:2px solid var(--primary);border-radius:8px;background:transparent;color:var(--primary);font-weight:600;font-size:.88rem;cursor:pointer;transition:all .25s;margin:4px}.reveal-btn:hover{background:var(--primary);color:#fff;transform:translateY(-1px);box-shadow:0 4px 12px #8e44ad33}.checklist{display:flex;flex-direction:column;gap:10px;margin:14px 0}.check-item{display:flex;align-items:center;gap:12px;background:var(--card-bg);border:1px solid var(--border-color);border-radius:12px;padding:12px 16px;cursor:pointer;transition:all .25s;font-size:.95rem;color:var(--text-dark)}.check-item:hover{border-color:var(--primary-light);box-shadow:0 3px 12px #8e44ad14}.check-item input[type=checkbox]{appearance:none;-webkit-appearance:none;width:22px;height:22px;border:2px solid var(--primary-light);border-radius:6px;cursor:pointer;flex-shrink:0;transition:all 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.poly-card{background:var(--card-bg);border-color:var(--border-color);color:var(--primary-light)}.alert{background:#f39c1214;border:1px solid rgba(243,156,18,.3);border-left:4px solid var(--accent);border-radius:0 12px 12px 0;padding:14px 18px;margin:16px 0;font-size:.95rem;font-weight:500;color:#7d6608;line-height:1.5}body.dark-mode .alert{background:#f39c121a;border-color:#f39c1240;color:#f9e79f}.graph-container{width:100%;max-width:400px;margin:0 auto 20px;background:var(--card-bg);border:1px solid var(--border-color);border-radius:14px;padding:14px;box-shadow:0 4px 16px #0000000a;transition:box-shadow .3s}.graph-container:hover{box-shadow:0 6px 24px #8e44ad1a}body.dark-mode .graph-container{border-color:var(--border-color);box-shadow:0 4px 16px #0003}.coord-input-group{display:flex;justify-content:center;gap:10px;margin:15px 0;flex-wrap:wrap;align-items:center}.coord-input{width:80px!important;max-width:80px!important;text-align:center}.action-btn{padding:10px 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ease}.check-btn:hover{background:var(--primary);color:#fff;transform:translateY(-2px);box-shadow:0 6px 16px #8e44ad33}.check-btn:active{transform:scale(.97)}.input-group{display:flex;gap:10px;margin:14px 0;flex-wrap:wrap;align-items:center}.angle-input{padding:10px 14px;border:2px solid var(--border-color);border-radius:10px;width:80px;text-align:center;font-size:1rem;font-weight:600;background:var(--card-bg);color:var(--text-dark);transition:border-color .3s,box-shadow .3s}.angle-input:focus{outline:none;border-color:var(--primary);box-shadow:0 0 0 3px #8e44ad1f}.game-btn{padding:10px 24px;background:linear-gradient(135deg,var(--accent),#e67e22);color:#fff;border:none;border-radius:10px;font-weight:700;font-size:.95rem;cursor:pointer;transition:all .25s ease;box-shadow:0 3px 12px #f39c1240}.game-btn:hover{transform:translateY(-2px);box-shadow:0 6px 20px #f39c1259}.sort-card{background:var(--card-bg);border:2px solid var(--border-color);border-radius:14px;padding:16px 20px;margin:10px 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solid rgba(39,174,96,.15);border-radius:12px;padding:14px 18px;text-align:center;font-size:1.1em;font-weight:600;color:var(--success);margin:12px 0}.shape-visual{width:120px;height:120px;margin:0 auto}.shape-label{fill:var(--text-dark);font-size:9px;font-weight:600}.iso-container{background:var(--card-bg);border:2px solid rgba(142,68,173,.15);border-radius:16px;padding:22px;margin:16px 0;text-align:center;position:relative;overflow:hidden;box-shadow:0 4px 20px #0000000a}.iso-container:before{content:"";position:absolute;top:0;left:0;right:0;height:3px;background:linear-gradient(90deg,var(--primary),var(--accent))}.carousel-container{position:relative;width:100%;max-width:500px;margin:0 auto 30px;overflow:hidden;border-radius:18px;background:var(--card-bg);border:1px solid var(--border-color);box-shadow:0 8px 28px #0000000f}.carousel-slide{display:none;padding:30px 24px 20px;text-align:center;animation:fadeSlide .4s ease}.carousel-slide.active{display:block}@keyframes 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.builder-box{background:linear-gradient(135deg,#9b59b614,#f39c120f);border-color:#9b59b633}body.dark-mode .sort-card{background:var(--card-bg);border-color:var(--border-color)}body.dark-mode .formula-box{background:linear-gradient(135deg,#27ae601a,#2ecc710f);border-color:#27ae6040}body.dark-mode .formula-highlight{background:#27ae6014;border-color:#27ae6033}body.dark-mode .angle-input{background:var(--card-bg);border-color:var(--border-color);color:var(--text-dark)}body.dark-mode .carousel-container{border-color:var(--border-color);box-shadow:0 8px 28px #0003}body.dark-mode .calculator-box,body.dark-mode .mean-calculator{border-color:#9b59b633}body.dark-mode .freq-table th{background:var(--primary-dark)}body.dark-mode .freq-table tbody tr:nth-child(2n){background:#9b59b60f}@media(max-width:600px){.interactive-box,.iso-container,.calculator-box,.mean-calculator{padding:16px}.carousel-container{border-radius:12px}.carousel-slide{padding:20px 16px 14px}.carousel-btn{width:30px;height:30px;font-size:.85rem}.angle-input{width:65px}.sort-card{padding:12px 14px}.formula-box{font-size:1rem}.shape-visual{width:90px;height:90px}}.text-muted{font-size:.85em;color:var(--text-light)}.angle-display{font-size:2.5rem;font-weight:800;color:var(--primary);margin:12px 0;letter-spacing:1px}.visual-container{background:var(--card-bg);border:1px solid var(--border-color);border-radius:16px;padding:20px;margin:16px 0;text-align:center;overflow:hidden}body.dark-mode .visual-container{border-color:var(--border-color)}