:root{--bg:#080c0a;--bg2:#0d1410;--bg3:#111a14;--green:#0f8;--green2:#00cc6a;--green-dim:#0f82;--red:#f36;--yellow:gold;--dim:#1e2e22;--border:#2a3a2e;--text:#c8e8d0;--muted:#5a7a62;--mono:"Share Tech Mono", monospace;--sans:"Syne", sans-serif;--radius:3px}*,:before,:after{box-sizing:border-box;margin:0;padding:0}html{-webkit-font-smoothing:antialiased;font-size:16px}body{background:var(--bg);color:var(--text);font-family:var(--mono);min-height:100vh;overflow-x:hidden}body:before{content:"";pointer-events:none;z-index:1000;background:repeating-linear-gradient(0deg,#0000,#0000 2px,#00ff8803 2px 4px);position:fixed;inset:0}.challenge-page{z-index:1;flex-direction:column;justify-content:center;align-items:center;min-height:100vh;padding:48px 24px;display:flex;position:relative}.challenge{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);width:100%;max-width:680px;padding:40px 40px 36px;animation:.6s both fadeUp;position:relative}.challenge:before{content:"";background:linear-gradient(90deg, var(--green), transparent);border-radius:var(--radius) var(--radius) 0 0;height:2px;position:absolute;top:0;left:0;right:0}@keyframes fadeUp{0%{opacity:0;transform:translateY(24px)}to{opacity:1;transform:translateY(0)}}.challenge-number{font-family:var(--sans);letter-spacing:3px;text-transform:uppercase;color:var(--muted);margin-bottom:10px;font-size:11px;font-weight:700}.challenge-number span{color:var(--green)}.challenge h1{font-family:var(--sans);color:#fff;letter-spacing:-.5px;margin-bottom:20px;font-size:clamp(22px,4vw,30px);font-weight:800;line-height:1.1}.challenge h1 em{color:var(--green);text-shadow:0 0 20px #0f86;font-style:normal}.challenge p{color:var(--text);margin-bottom:20px;font-size:13px;line-height:1.8}.challenge-divider{border:none;border-top:1px solid var(--dim);margin:28px 0}.tags{flex-wrap:wrap;gap:8px;margin-bottom:28px;display:flex}.tag{letter-spacing:1.5px;text-transform:uppercase;border:1px solid;border-radius:2px;padding:3px 10px;font-size:10px}.tag-type{border-color:var(--border);color:var(--muted);background:0 0}.tag-easy{color:#0f8;background:#00ff880f;border-color:#0f8}.tag-medium{color:gold;background:#ffd7000f;border-color:gold}.tag-hard{color:#f80;background:#ff88000f;border-color:#f80}.tag-expert{color:#f36;background:#ff33660f;border-color:#f36}.terminal{border:1px solid var(--dim);border-radius:var(--radius);background:#000;margin-bottom:24px;font-size:12px;overflow:hidden}.terminal-bar{background:#111;border-bottom:1px solid #1a1a1a;align-items:center;gap:6px;padding:8px 12px;display:flex}.terminal-dot{border-radius:50%;width:10px;height:10px}.terminal-dot.red{background:#ff5f57}.terminal-dot.yellow{background:#ffbd2e}.terminal-dot.green{background:#28ca41}.terminal-label{color:#444;letter-spacing:.5px;flex:1;margin-left:6px;font-size:11px}.terminal-body{color:var(--muted);min-height:80px;padding:16px 18px;line-height:1.7}.terminal-body .line-green{color:var(--green)}.terminal-body .line-yellow{color:var(--yellow)}.terminal-body .line-red{color:var(--red)}.terminal-body .line-dim{color:#333}.terminal-body .line-white{color:#fff}code{font-family:var(--mono);color:var(--green);background:#00ff8812;border:1px solid #00ff8826;border-radius:2px;padding:1px 6px;font-size:.9em}.flag-submit{align-items:stretch;gap:8px;margin-top:8px;display:flex}.flag-input{border:1px solid var(--border);color:var(--green);font-family:var(--mono);border-radius:var(--radius);letter-spacing:.5px;background:#050505;outline:none;flex:1;padding:11px 16px;font-size:13px;transition:border-color .2s,box-shadow .2s}.flag-input::placeholder{color:var(--muted)}.flag-input:focus{border-color:var(--green2);box-shadow:0 0 0 3px #00cc6a14}.flag-input.error{border-color:var(--red);animation:.35s shake}.flag-input.success{border-color:var(--green);box-shadow:0 0 0 3px #00ff881a}@keyframes shake{0%,to{transform:translate(0)}25%{transform:translate(-6px)}75%{transform:translate(6px)}}button,.btn{background:var(--green-dim);border:1px solid var(--green2);color:var(--green);font-family:var(--mono);letter-spacing:1.5px;text-transform:uppercase;cursor:pointer;border-radius:var(--radius);white-space:nowrap;padding:11px 22px;font-size:12px;transition:background .15s,box-shadow .15s}button:hover,.btn:hover{background:#00ff8824;box-shadow:0 0 12px #0f83}button:active,.btn:active{transform:translateY(1px)}.btn-ghost{border-color:var(--border);color:var(--muted);background:0 0}.btn-ghost:hover{border-color:var(--green2);color:var(--green);box-shadow:none}.flag-msg{letter-spacing:.5px;min-height:18px;margin-top:10px;font-size:12px}.flag-msg.ok{color:var(--green)}.flag-msg.err{color:var(--red)}.hint-section{border-top:1px solid var(--dim);margin-top:28px;padding-top:20px}.hint-toggle{color:var(--muted);font-family:var(--mono);letter-spacing:1px;cursor:pointer;text-transform:uppercase;box-shadow:none;background:0 0;border:none;padding:0;font-size:11px;transition:color .15s}.hint-toggle:hover{color:var(--text);box-shadow:none;background:0 0}.hint-toggle:active{transform:none}.hints-list{border-left:2px solid var(--dim);margin-top:14px;padding-left:16px;list-style:none;display:none}.hints-list.open{display:block}.hint-item{color:var(--muted);cursor:pointer;gap:10px;margin-bottom:6px;font-size:12px;line-height:1.7;transition:color .15s;display:flex}.hint-item:hover{color:var(--text)}.hint-item.revealed{color:var(--text);cursor:default}.hint-num{color:var(--dim);-webkit-user-select:none;user-select:none;flex-shrink:0}.challenge h2{font-family:var(--sans);color:var(--muted);letter-spacing:2px;text-transform:uppercase;margin-bottom:10px;font-size:13px;font-weight:700}.objective{border-radius:var(--radius);color:var(--text);background:#00ff880a;border:1px solid #00ff8826;margin-bottom:24px;padding:12px 16px;font-size:12px;line-height:1.7}.objective strong{color:var(--yellow)}.challenge.solved{border-color:var(--green);box-shadow:0 0 30px #00ff8814}.challenge.solved:before{background:var(--green)}.solved-banner{text-align:center;border:1px solid var(--green2);border-radius:var(--radius);color:var(--green);letter-spacing:2px;background:#00ff880f;margin-top:20px;padding:14px;font-size:13px;display:none}.challenge.solved .solved-banner{display:block}.nav-back{color:var(--muted);letter-spacing:1px;align-items:center;gap:8px;margin-bottom:32px;font-size:12px;text-decoration:none;transition:color .15s;display:inline-flex}.nav-back:hover{color:var(--green)}::-webkit-scrollbar{width:4px}::-webkit-scrollbar-track{background:var(--bg)}::-webkit-scrollbar-thumb{background:var(--dim);border-radius:2px}.text-green{color:var(--green)}.text-yellow{color:var(--yellow)}.text-red{color:var(--red)}.text-muted{color:var(--muted)}.text-white{color:#fff}.mt-8{margin-top:8px}.mt-16{margin-top:16px}.mt-24{margin-top:24px}.mb-8{margin-bottom:8px}.mb-16{margin-bottom:16px}.mb-24{margin-bottom:24px}@media (width<=600px){.challenge{padding:28px 22px 24px}.flag-submit{flex-direction:column}button,.btn{justify-content:center;width:100%}}