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var(--border)}.admin-sidebar{width:var(--sidebar-width);background:var(--surface);border-right:1px solid var(--border);height:100vh;position:fixed;left:0;top:var(--nav-height);padding:1.5rem 0;overflow-y:auto}.admin-nav-item{display:flex;align-items:center;gap:.75rem;padding:.75rem 1.5rem;font-weight:500;color:var(--text-secondary);transition:all var(--transition-fast)}.admin-nav-item:hover{background:var(--bg-alt);color:var(--text)}.admin-nav-item.active{background:var(--primary-50);color:var(--primary);border-right:3px solid var(--primary);font-weight:600}.admin-content{margin-left:var(--sidebar-width);padding:2rem;min-height:calc(100vh - var(--nav-height))}@media (max-width:768px){.admin-sidebar{display:none}.admin-content{margin-left:0}}.filter-bar{display:flex;gap:.75rem;flex-wrap:wrap;padding:1rem;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-lg);margin-bottom:1.5rem}.filter-chip{padding:.5rem 1rem;border:2px solid 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var(--border);padding-top:2rem;display:flex;justify-content:space-between;align-items:center;font-size:.85rem;color:var(--text-muted)}@media (max-width:768px){.footer-grid{grid-template-columns:1fr 1fr;gap:2rem}}@media (max-width:480px){.footer-grid{grid-template-columns:1fr}}@keyframes fadeInUp{0%{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}@keyframes fadeInRight{0%{opacity:0;transform:translateX(30px)}to{opacity:1;transform:translateX(0)}}@keyframes slideDown{0%{opacity:0;transform:translateY(-10px)}to{opacity:1;transform:translateY(0)}}@keyframes float{0%,to{transform:translateY(0)}50%{transform:translateY(-12px)}}@keyframes floatBg{0%,to{transform:translate(0) scale(1)}33%{transform:translate(30px,-20px) scale(1.05)}66%{transform:translate(-20px,15px) scale(.95)}}@keyframes pulse{0%,to{opacity:1}50%{opacity:.5}}@keyframes shimmer{0%{background-position:-200%}to{background-position:200%}}@keyframes confetti{0%{transform:translateY(0) 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ease}.modal{background:var(--surface);border-radius:var(--radius-xl);padding:2rem;max-width:500px;width:90%;max-height:90vh;overflow-y:auto;z-index:9999;animation:scaleIn .3s ease}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}.tabs{display:flex;border-bottom:2px solid var(--border);gap:0;overflow-x:auto}.tab{padding:.75rem 1.5rem;font-weight:500;font-size:.9rem;color:var(--text-muted);border-bottom:2px solid transparent;margin-bottom:-2px;transition:all var(--transition-fast);white-space:nowrap;cursor:pointer}.tab:hover{color:var(--text)}.tab.active{color:var(--primary);border-bottom-color:var(--primary);font-weight:600}.empty-state{text-align:center;padding:4rem 2rem}.empty-state-icon{font-size:4rem;margin-bottom:1rem}.empty-state h3{margin-bottom:.5rem}.empty-state p{color:var(--text-muted);max-width:400px;margin:0 auto 1.5rem}.material-card{display:flex;align-items:center;gap:1rem;padding:1rem 1.25rem;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-md);transition:all var(--transition-fast);cursor:pointer}.material-card:hover{border-color:var(--primary-200);box-shadow:var(--shadow-md)}.material-icon{width:48px;height:48px;background:var(--danger-bg);border-radius:var(--radius-md);display:flex;align-items:center;justify-content:center;font-size:1.3rem;flex-shrink:0}::-webkit-scrollbar{width:6px}::-webkit-scrollbar-track{background:transparent}::-webkit-scrollbar-thumb{background:var(--border);border-radius:var(--radius-full)}::-webkit-scrollbar-thumb:hover{background:var(--text-muted)}@media print{.btn,.footer,.nav-mobile,.navbar{display:none!important}body{background:white}}.hero:after{content:"";position:absolute;inset:0;opacity:.02;z-index:0;pointer-events:none;background-image:url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noiseFilter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.65' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noiseFilter)'/%3E%3C/svg%3E")}.card-premium{position:relative;background:var(--surface);border-radius:var(--radius-xl);padding:2rem;border:none;box-shadow:var(--shadow-lg)}.card-premium:before{content:"";position:absolute;inset:0;border-radius:var(--radius-xl);padding:1.5px;background:linear-gradient(135deg,var(--primary-light),var(--accent),var(--primary-light));-webkit-mask:linear-gradient(#fff 0 0) content-box,linear-gradient(#fff 0 0);-webkit-mask-composite:xor;mask-composite:exclude;pointer-events:none}main{animation:pageEnter .4s cubic-bezier(.4,0,.2,1)}@keyframes pageEnter{0%{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}.btn-primary:focus-visible{outline:none;box-shadow:var(--shadow-md),0 0 0 3px rgba(99,102,241,.3)}.btn-outline:focus-visible{outline:none;box-shadow:0 0 0 3px rgba(99,102,241,.15)}.stat-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-lg);padding:1.25rem;text-align:center;transition:all var(--transition-base);box-shadow:var(--shadow-card);position:relative;overflow:hidden}.stat-card:after{content:"";position:absolute;top:-50%;left:-50%;width:200%;height:200%;background:radial-gradient(circle at center,rgba(99,102,241,.03) 0,transparent 70%);pointer-events:none}.stat-card:hover{transform:translateY(-3px);box-shadow:var(--shadow-lg);border-color:var(--primary-200)}.leaderboard-row{display:flex;align-items:center;gap:1rem;padding:1rem 1.25rem;border-radius:var(--radius-md);transition:all var(--transition-fast)}.leaderboard-row:hover{background:var(--primary-50)}.leaderboard-row.top-1{background:linear-gradient(135deg,rgba(255,215,0,.08),rgba(255,215,0,.02))}.leaderboard-row.top-2{background:linear-gradient(135deg,rgba(192,192,192,.08),rgba(192,192,192,.02))}.leaderboard-row.top-3{background:linear-gradient(135deg,rgba(205,127,50,.08),rgba(205,127,50,.02))}.option{display:flex;align-items:center;gap:1rem;padding:1rem 1.25rem;border:2px solid var(--border);border-radius:var(--radius-md);margin-bottom:.75rem;cursor:pointer;transition:all .2s cubic-bezier(.4,0,.2,1);font-weight:500}.option:hover{border-color:var(--primary-light);background:var(--primary-50);transform:translateX(4px)}.option.selected{border-color:var(--primary);background:var(--primary-50);color:var(--primary);box-shadow:0 0 0 3px rgba(99,102,241,.1)}.hero-card-stack:before{content:"";position:absolute;top:50%;left:50%;width:200px;height:200px;transform:translate(-50%,-50%);background:radial-gradient(circle,rgba(99,102,241,.08) 0,transparent 70%);border-radius:50%;animation:pulse 3s ease-in-out infinite;z-index:0}.question-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-xl);padding:2rem;margin-bottom:1.5rem;box-shadow:var(--shadow-card)}.badge{display:inline-flex;align-items:center;gap:.25rem;padding:.3rem .85rem;font-size:.73rem;font-weight:600;border-radius:var(--radius-full);text-transform:uppercase;letter-spacing:.6px}.tier-gold{background:linear-gradient(135deg,#FFD700,#FFA500);color:#333;box-shadow:0 2px 12px rgba(255,215,0,.3)}.tier-platinum{background:linear-gradient(135deg,#E5E4E2,#B0B0B0);color:#333;box-shadow:0 2px 12px rgba(229,228,226,.3)}.tier-diamond{background:linear-gradient(135deg,#B9F2FF,#00CED1);color:#333;box-shadow:0 2px 12px rgba(0,206,209,.3)}.footer{background:var(--surface);border-top:1px solid var(--border);padding:4rem 0 2rem;position:relative}.footer:before{content:"";position:absolute;top:0;left:0;right:0;height:1px;background:linear-gradient(90deg,transparent,var(--primary-light),transparent)}::selection{background:rgba(99,102,241,.2);color:var(--text)}a{text-decoration:none;color:inherit;transition:color var(--transition-fast)}:focus-visible{outline:2px solid var(--primary);outline-offset:2px}button:focus-visible{outline:2px solid var(--primary);outline-offset:2px}