:root{--accent-cyan: #22d3ee;--accent-purple: #c084fc;--accent-green: #4ade80;--accent-red: #f87171;--accent-yellow: #facc15;--text-main: #ffffff;--text-muted: #94a3b8;--card-bg: rgba(15, 23, 42, .6);--card-border: rgba(255, 255, 255, .1)}body{background-color:#050505;color:var(--text-main);font-family:Inter,sans-serif;overflow-x:hidden;min-height:100vh}.fixed-bg{position:fixed;top:0;left:0;width:100%;height:100%;z-index:-2;background-image:var(--background-desktop);background-size:cover;background-position:center bottom}.overlay{position:fixed;top:0;left:0;width:100%;height:100%;background:#00000059;z-index:-1}main{padding:8rem 2rem 6rem;max-width:1200px;margin:0 auto}.page-header{text-align:center;margin-bottom:4rem;opacity:0;animation:fadeDown .8s forwards}.page-title{font-family:Cinzel;font-size:3rem;margin-bottom:1rem;letter-spacing:2px}.page-desc{color:var(--text-muted);font-family:JetBrains Mono;max-width:600px;margin:0 auto}.control-panel{background:#1e293b80;border:1px solid var(--card-border);border-radius:12px;padding:1.5rem;margin-bottom:3rem;display:flex;flex-wrap:wrap;gap:1.5rem;align-items:center;justify-content:space-between;backdrop-filter:blur(10px);opacity:0;animation:fadeUp .8s .2s forwards}.search-box{position:relative;flex:1;min-width:250px}.search-input{width:100%;background:#0000004d;border:1px solid var(--card-border);padding:12px 15px 12px 40px;border-radius:6px;color:#fff;font-family:JetBrains Mono;transition:.3s;outline:none}.search-input:focus{border-color:var(--accent-cyan);box-shadow:0 0 10px #22d3ee33}.search-icon{position:absolute;left:12px;top:50%;transform:translateY(-50%);color:var(--text-muted);width:16px;height:16px}.filter-group{display:flex;gap:.5rem;flex-wrap:wrap}.filter-btn{background:transparent;border:1px solid transparent;color:var(--text-muted);padding:6px 16px;border-radius:20px;font-size:.85rem;cursor:pointer;transition:.3s;font-family:JetBrains Mono;font-weight:600}.filter-btn:hover{background:#ffffff0d;color:#fff}.filter-btn.active{background:var(--accent-cyan);color:#000;box-shadow:0 0 15px #22d3ee66}.challenges-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(340px,1fr));gap:2rem}.chal-card{background:var(--card-bg);border:1px solid var(--card-border);border-radius:8px;padding:1.5rem;position:relative;transition:transform .3s,border-color .3s,box-shadow .3s;display:flex;flex-direction:column;opacity:0}.chal-card:hover{transform:translateY(-5px);border-color:var(--accent-cyan);box-shadow:0 10px 30px #00000080}.chal-card.solved{border-color:var(--accent-cyan);background:#22d3ee0d}.chal-card.solved:before{content:"SOLVED";position:absolute;top:10px;right:10px;background:var(--accent-cyan);color:#000;font-size:.6rem;font-weight:700;padding:2px 6px;border-radius:4px}.chal-header{display:flex;justify-content:space-between;align-items:flex-start;margin-bottom:1rem}.chal-category{font-family:JetBrains Mono;font-size:.75rem;font-weight:700;padding:4px 8px;border-radius:4px;text-transform:uppercase}.cat-web{color:var(--accent-cyan);border:1px solid rgba(34,211,238,.3);background:#22d3ee1a}.cat-pwn{color:var(--accent-red);border:1px solid rgba(248,113,113,.3);background:#f871711a}.cat-re{color:var(--accent-purple);border:1px solid rgba(192,132,252,.3);background:#c084fc1a}.cat-misc{color:var(--accent-green);border:1px solid rgba(74,222,128,.3);background:#4ade801a}.cat-crypto{color:var(--accent-yellow);border:1px solid rgba(250,204,21,.3);background:#facc151a}.chal-points{font-family:JetBrains Mono;color:#fff;font-weight:700;font-size:1.1rem}.chal-title{font-size:1.25rem;font-weight:600;margin-bottom:.5rem;color:#fff}.chal-tags{display:flex;gap:8px;margin-bottom:1rem;flex-wrap:wrap}.tag-pill{font-size:.7rem;color:var(--text-muted);background:#ffffff0d;padding:2px 8px;border-radius:10px;border:1px solid rgba(255,255,255,.1)}.chal-desc{color:var(--text-muted);font-size:.9rem;line-height:1.6;flex-grow:1;margin-bottom:1.5rem}.chal-footer{display:flex;flex-direction:column;gap:12px;margin-top:auto;padding-top:1rem;border-top:1px solid rgba(255,255,255,.05)}.chal-meta{display:flex;justify-content:space-between;align-items:center}.chal-author{font-size:.8rem;color:#64748b;font-family:JetBrains Mono}.download-btn{background:transparent;color:var(--accent-cyan);text-decoration:none;border:1px solid var(--accent-cyan);font-family:JetBrains Mono;font-weight:700;font-size:.8rem;padding:6px 12px;border-radius:4px;display:flex;align-items:center;gap:6px;transition:.3s}.download-btn:hover{background:var(--accent-cyan);color:#000}.difficulty-dot{width:8px;height:8px;border-radius:50%;display:inline-block;margin-right:5px}.diff-easy{background:var(--accent-green);box-shadow:0 0 5px var(--accent-green)}.diff-med{background:var(--accent-yellow);box-shadow:0 0 5px var(--accent-yellow)}.diff-hard{background:var(--accent-red);box-shadow:0 0 5px var(--accent-red)}.flag-input-group{display:flex;gap:8px}.flag-input{flex:1;background:#0000004d;border:1px solid var(--card-border);color:#fff;padding:6px 10px;border-radius:4px;font-family:JetBrains Mono;font-size:.85rem;outline:none}.flag-input:focus{border-color:var(--accent-cyan)}.submit-btn{background:var(--accent-cyan);color:#000;border:none;padding:0 12px;border-radius:4px;font-weight:700;cursor:pointer;font-family:JetBrains Mono;transition:.3s}.submit-btn:hover{opacity:.9}.solved .flag-input-group{display:none}.score-board{font-family:JetBrains Mono;color:var(--text-main);font-weight:700;display:flex;align-items:center;gap:10px;margin-right:20px}.score-num{color:var(--accent-yellow);font-size:1.2rem}@keyframes fadeDown{0%{opacity:0;transform:translateY(-20px)}to{opacity:1;transform:translateY(0)}}@keyframes fadeUp{0%{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}@keyframes shake{0%,to{transform:translate(0)}25%{transform:translate(-5px)}75%{transform:translate(5px)}}.shake{animation:shake .3s ease-in-out;border-color:var(--accent-red)!important}.modal-overlay{position:fixed;top:0;left:0;width:100%;height:100%;background:#0009;backdrop-filter:blur(8px);z-index:1000;display:none;justify-content:center;align-items:center;opacity:0;transition:opacity .3s ease}.modal-overlay.active{opacity:1}.modal-box{background:#0f172ae6;border:1px solid var(--accent-cyan);border-radius:12px;padding:3rem 4rem;text-align:center;box-shadow:0 0 50px #22d3ee33,inset 0 0 20px #22d3ee1a;transform:scale(.9);transition:transform .3s cubic-bezier(.175,.885,.32,1.275);max-width:90%}.modal-overlay.active .modal-box{transform:scale(1)}.modal-icon{width:80px;height:80px;background:#22d3ee1a;border-radius:50%;display:flex;justify-content:center;align-items:center;margin:0 auto 1.5rem;color:var(--accent-cyan);box-shadow:0 0 20px #22d3ee4d}.modal-title{font-family:Cinzel,serif;font-size:2rem;color:#fff;margin-bottom:.5rem;letter-spacing:2px}.modal-subtitle{font-family:JetBrains Mono;color:var(--accent-cyan);font-size:1.2rem;margin-bottom:2rem;font-weight:700}.modal-btn{background:var(--accent-cyan);color:#000;border:none;padding:10px 30px;border-radius:4px;font-weight:700;cursor:pointer;font-family:JetBrains Mono;font-size:1rem;transition:.3s;text-transform:uppercase}.modal-btn:hover{background:#fff;box-shadow:0 0 20px var(--accent-cyan)}@media(max-width:768px){.fixed-bg{background-image:var(--background-mobile)}}