:root{--primary: #8b5cf6;--primary-hover: #7c3aed;--bg-gradient: linear-gradient(135deg, #0f172a 0%, #1e1b4b 100%);--glass: rgba(255, 255, 255, .05);--glass-border: rgba(255, 255, 255, .1);--text: #f8fafc;--text-muted: #94a3b8}*{margin:0;padding:0;box-sizing:border-box}body{font-family:Inter,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif;background:var(--bg-gradient);color:var(--text);min-height:100vh;display:flex;justify-content:center;align-items:center;overflow-x:hidden}#root{width:100%;max-width:1000px;padding:2rem}.container{background:var(--glass);backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);border:1px solid var(--glass-border);border-radius:24px;padding:3rem;box-shadow:0 25px 50px -12px #00000080;animation:fadeIn .8s ease-out}@keyframes fadeIn{0%{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}h1{font-size:2.5rem;font-weight:800;margin-bottom:.5rem;background:linear-gradient(to 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0}.progress-bar{height:100%;background:var(--primary);transition:width .3s ease}.result-area{margin-top:2rem;background:#0003;border-radius:16px;padding:1.5rem;border:1px solid var(--glass-border);position:relative}.result-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:1rem}.result-text{white-space:pre-wrap;font-family:Fira Code,monospace;font-size:.95rem;line-height:1.6;color:#e2e8f0;max-height:400px;overflow-y:auto;padding-right:1rem}.edit-box{width:100%;min-height:200px;background:#0006;border:1px solid var(--primary);color:#f8fafc;padding:1rem;border-radius:12px;resize:vertical;outline:none;font-family:inherit;font-size:.95rem;margin-bottom:1rem}.edit-box:focus{box-shadow:0 0 15px #8b5cf64d}.edit-container{display:flex;flex-direction:column;gap:.5rem;width:100%}.markdown-content p{line-height:1.6}.btn-copy{background:var(--primary);color:#fff;border:none;padding:.6rem 1.2rem;border-radius:8px;font-weight:600;cursor:pointer;transition:all 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slideIn{0%{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}.ai-header{display:flex;align-items:center;gap:.75rem;margin-bottom:1.5rem;padding-bottom:1rem;border-bottom:1px solid rgba(255,255,255,.05)}.ai-badge{background:#8b5cf633;color:#c084fc;padding:.25rem .75rem;border-radius:999px;font-size:.75rem;font-weight:700;text-transform:uppercase}.ai-content{color:#e2e8f0;font-size:1rem;line-height:1.7}.ai-content h1,.ai-content h2,.ai-content h3{margin:1.5rem 0 1rem;color:#f8fafc}.ai-content p{margin-bottom:1rem}.ai-content ul,.ai-content ol{margin-bottom:1rem;padding-left:1.5rem}.ai-content code{background:#0000004d;padding:.2rem .4rem;border-radius:4px;font-family:Fira Code,monospace;font-size:.9em}.ai-content pre{background:#0006;padding:1.5rem;border-radius:12px;overflow-x:auto;margin:1rem 0}.loading-ai{display:flex;flex-direction:column;align-items:center;gap:1rem;padding:2rem;color:var(--text-muted)}.mode-selection-container{margin:2rem 0;padding:1.5rem;background:#ffffff08;border-radius:20px;border:1px solid var(--glass-border)}.mode-header{display:flex;align-items:center;gap:.75rem;margin-bottom:1.25rem}.mode-toggle{display:flex;background:#0000004d;padding:.4rem;border-radius:12px;gap:.4rem;width:fit-content}.mode-btn{background:transparent;border:none;color:var(--text-muted);padding:.6rem 1.2rem;border-radius:8px;cursor:pointer;font-weight:600;transition:all .3s ease;display:flex;align-items:center;gap:.5rem}.mode-btn:hover{color:var(--text);background:#ffffff0d}.mode-btn.active{background:var(--primary);color:#fff;box-shadow:0 4px 12px #8b5cf64d}.manual-ref-container{margin-top:1.5rem;animation:fadeIn .4s ease-out}.reference-box{width:100%;min-height:150px;background:#0006;border:1px solid var(--glass-border);color:#f8fafc;padding:1rem;border-radius:12px;resize:vertical;outline:none;font-family:inherit;font-size:.95rem;line-height:1.6;margin-bottom:.5rem;transition:border-color .3s ease}.reference-box:focus{border-color:var(--primary)}.btn-set-ref{background:#10b9811a;color:#10b981;border:1px solid #10b981;padding:.4rem .8rem;border-radius:6px;font-size:.8rem;font-weight:600;cursor:pointer;transition:all .2s;display:flex;align-items:center;gap:.4rem}.btn-set-ref:hover{background:#10b981;color:#fff}.stepper{display:flex;justify-content:space-between;align-items:center;margin-bottom:3rem;position:relative;max-width:800px;margin-left:auto;margin-right:auto}.stepper:before{content:"";position:absolute;top:20px;left:0;right:0;height:2px;background:var(--glass-border);z-index:1}.step-item{position:relative;z-index:2;display:flex;flex-direction:column;align-items:center;gap:.75rem;cursor:pointer;transition:all .3s ease}.step-item:hover:not(.disabled) .step-number{transform:scale(1.1);border-color:var(--primary)}.step-item.disabled{cursor:not-allowed;opacity:.7}.step-number{width:40px;height:40px;border-radius:50%;background:#1e293b;border:2px solid var(--glass-border);display:flex;align-items:center;justify-content:center;font-weight:700;color:var(--text-muted);transition:all .4s cubic-bezier(.4,0,.2,1)}.step-item.active .step-number{background:var(--primary);border-color:var(--primary);color:#fff;box-shadow:0 0 20px #8b5cf666;transform:scale(1.1)}.step-item.completed .step-number{background:#10b981;border-color:#10b981;color:#fff}.step-label{font-size:.8rem;font-weight:600;color:var(--text-muted);text-transform:uppercase;letter-spacing:.05em}.step-item.active .step-label{color:var(--text)}.nav-footer{display:flex;justify-content:space-between;align-items:center;margin-top:3rem;padding-top:2rem;border-top:1px solid var(--glass-border)}.btn-nav{display:flex;align-items:center;gap:.75rem;padding:.8rem 1.8rem;border-radius:12px;font-weight:700;cursor:pointer;transition:all .3s ease;border:1px solid transparent}.grading-markdown{color:#e2e8f0;line-height:1.6}.grading-markdown h1{color:#fff;border-bottom:2px solid var(--glass-border);padding-bottom:.5rem;margin-bottom:1.5rem;font-size:1.5rem}.grading-markdown h3{color:#a78bfa;margin-top:1.5rem;margin-bottom:1rem}.grading-markdown ul{list-style-type:disc;margin-left:1.5rem;margin-bottom:1rem}.grading-markdown ul ul{list-style-type:circle;margin-top:.5rem;background:#ffffff08;padding:.8rem 1.2rem;border-radius:8px;border-left:3px solid var(--primary)}.grading-markdown li{margin-bottom:.5rem}.grading-markdown strong{color:var(--primary);font-weight:600}.grading-markdown hr{border:none;border-top:1px solid var(--glass-border);margin:2rem 0}.btn-nav-back{background:#ffffff0d;color:var(--text);border-color:var(--glass-border)}.btn-nav-next{background:var(--primary);color:#fff;box-shadow:0 4px 15px #8b5cf64d}.btn-nav:hover{transform:translateY(-2px);filter:brightness(1.1)}.btn-nav:disabled{opacity:.4;cursor:not-allowed;transform:none}.btn-nav-back:hover{background:#ffffff1a}.step-content{animation:slideInRight .5s ease-out}@keyframes slideInRight{0%{opacity:0;transform:translate(20px)}to{opacity:1;transform:translate(0)}}