*{box-sizing:border-box;margin:0;padding:0}:root{--primary: #6366f1;--primary-dark: #4f46e5;--secondary: #8b5cf6;--success: #10b981;--danger: #ef4444;--warning: #f59e0b;--bg: #0f172a;--bg-light: #1e293b;--bg-lighter: #334155;--text: #f1f5f9;--text-muted: #94a3b8;--border: #334155}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,Fira Sans,Droid Sans,Helvetica Neue,sans-serif;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;background:var(--bg);color:var(--text);line-height:1.6}#root{min-height:100vh}.container{max-width:1200px;margin:0 auto;padding:0 1rem}.btn{padding:.75rem 1.5rem;border:none;border-radius:.5rem;font-size:1rem;font-weight:500;cursor:pointer;transition:all .2s;display:inline-flex;align-items:center;justify-content:center;gap:.5rem}.btn:disabled{opacity:.5;cursor:not-allowed}.btn-primary{background:var(--primary);color:#fff}.btn-primary:hover:not(:disabled){background:var(--primary-dark)}.btn-success{background:var(--success);color:#fff}.btn-danger{background:var(--danger);color:#fff}.btn-secondary{background:var(--bg-lighter);color:var(--text)}.btn-secondary:hover:not(:disabled){background:var(--border)}.btn-sm{padding:.5rem 1rem;font-size:.875rem}.input,.textarea{width:100%;padding:.75rem;border:1px solid var(--border);border-radius:.5rem;background:var(--bg-light);color:var(--text);font-size:1rem;font-family:inherit}.input:focus,.textarea:focus{outline:none;border-color:var(--primary)}.textarea{resize:vertical;min-height:100px}.card{background:var(--bg-light);border-radius:.75rem;padding:1.5rem;border:1px solid var(--border)}.header{background:var(--bg-light);border-bottom:1px solid var(--border);padding:1rem 0;position:sticky;top:0;z-index:100}.nav{display:flex;justify-content:space-between;align-items:center;gap:1rem}.nav-brand{display:flex;align-items:center;justify-content:space-between;width:100%}.nav-brand h2{margin:0}.hamburger{display:none;flex-direction:column;gap:4px;background:none;border:none;cursor:pointer;padding:.5rem;z-index:1001}.hamburger span{width:25px;height:3px;background:var(--text);border-radius:3px;transition:all .3s ease}.nav-backdrop{display:none}.nav-menu{display:flex;align-items:center;gap:2rem;width:100%;justify-content:space-between}.nav-links{display:flex;gap:1rem;list-style:none;margin:0;padding:0}.nav-links a{color:var(--text);text-decoration:none;padding:.5rem 1rem;border-radius:.375rem;transition:background .2s;white-space:nowrap}.nav-links a:hover,.nav-links a.active{background:var(--bg-lighter)}.logout-btn{white-space:nowrap}.grid{display:grid;gap:1rem}.grid-2{grid-template-columns:repeat(auto-fill,minmax(300px,1fr))}.form-group{margin-bottom:1rem}.form-group label{display:block;margin-bottom:.5rem;font-weight:500;color:var(--text-muted)}.error{color:var(--danger);font-size:.875rem;margin-top:.5rem}.success{color:var(--success);font-size:.875rem;margin-top:.5rem}.loading{display:flex;justify-content:center;align-items:center;min-height:200px;color:var(--text-muted)}.challenge-detail-layout{display:grid;gap:2rem;grid-template-columns:minmax(0,1fr) 300px}#leaderboard-mobile{display:none}@media (max-width: 768px){.nav-brand{width:100%}.hamburger{display:flex}.nav-backdrop{display:block;position:fixed;top:0;left:0;width:100%;height:100vh;background:#00000080;z-index:999;animation:fadeIn .3s ease}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}.hamburger.active span:nth-child(1){transform:rotate(45deg) translate(5px,5px)}.hamburger.active span:nth-child(2){opacity:0}.hamburger.active span:nth-child(3){transform:rotate(-45deg) translate(7px,-7px)}.nav-menu{position:fixed;top:0;right:-100%;width:70%;height:100vh;background:var(--bg-light);border-left:1px solid var(--border);flex-direction:column;justify-content:flex-start;padding:5rem 2rem 2rem;gap:2rem;transition:right .3s ease;z-index:1000}.nav-menu.active{right:0}.nav-links{flex-direction:column;width:100%;gap:0}.nav-links li{width:100%}.nav-links a{display:block;padding:1rem;font-size:1.125rem;width:100%;border-bottom:1px solid var(--border);border-radius:0}.nav-links a:hover{background:var(--bg-lighter);border-radius:0}.logout-btn{width:100%}.card{padding:1rem}.grid-2{grid-template-columns:1fr}.btn{width:100%}#leaderboard-mobile{display:block}.challenge-sidebar{display:none}.challenge-detail-layout{grid-template-columns:1fr}}@media (max-width: 1024px){[style*="grid-template-columns: minmax(0, 1fr) 300px"]{grid-template-columns:1fr!important}}