:root{--bg: #0b1220;--surface: #131c2e;--surface-2: #1b2740;--border: #263450;--text: #e6edf7;--muted: #8797b0;--accent: #38bdf8;--accent-ink: #04121f;--danger: #ef4444;color-scheme:dark}*{box-sizing:border-box}body{margin:0;font-family:ui-sans-serif,system-ui,-apple-system,Segoe UI,Roboto,sans-serif;background:radial-gradient(1200px 600px at 50% -10%,#16233b 0%,var(--bg) 60%);color:var(--text);min-height:100vh}.app{max-width:640px;margin:0 auto;padding:max(16px,env(safe-area-inset-top)) 16px 40px}header{display:flex;align-items:center;justify-content:space-between;padding:8px 0 16px}header h1{margin:0;font-size:1.35rem;letter-spacing:-.02em}.muted{color:var(--muted)}.small{font-size:.82rem}.center{text-align:center}.grow{flex:1}.row{display:flex;align-items:center}.row.gap{gap:10px}.row.between{justify-content:space-between}.stack{display:flex;flex-direction:column;gap:14px}.dot{width:10px;height:10px;border-radius:50%;background:var(--muted)}.dot.on{background:#22c55e;box-shadow:0 0 8px #22c55e88}.dot.off{background:var(--danger)}.tabs{display:flex;gap:6px;margin-bottom:16px;overflow-x:auto;-webkit-overflow-scrolling:touch}.tab{flex:1 0 auto;background:var(--surface);border:1px solid var(--border);color:var(--muted);padding:10px 14px;border-radius:10px;cursor:pointer;font-weight:600;position:relative;white-space:nowrap}.tab.active{color:var(--text);border-color:var(--accent);background:var(--surface-2)}.pill{margin-left:6px;background:var(--accent);color:var(--accent-ink);border-radius:999px;padding:1px 7px;font-size:.72rem}.card{background:var(--surface);border:1px solid var(--border);border-radius:14px;padding:20px;display:flex;flex-direction:column;gap:12px}.card.warn{border-color:#a16207;background:#1f1a0b}.card h2{margin:0;font-size:1.1rem}.prompt{font-size:1.15rem;line-height:1.5;margin:4px 0}label{display:flex;flex-direction:column;gap:6px;font-size:.82rem;color:var(--muted)}textarea,input,select{background:var(--bg);border:1px solid 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12px;font-size:.8rem;font-weight:700;white-space:nowrap;cursor:pointer}.col-right{display:flex;flex-direction:column;align-items:flex-end;gap:6px}.link.inline{display:inline;font-weight:700}.upgrade-card{flex-direction:row;align-items:center;justify-content:space-between;gap:12px;border-color:#a16207;background:linear-gradient(180deg,#1f1a0b,var(--surface))}.upgrade-card p{margin-top:4px}.modal-backdrop{position:fixed;top:0;right:0;bottom:0;left:0;background:#03060cbf;display:flex;align-items:center;justify-content:center;padding:16px;z-index:100}.modal{background:var(--surface);border:1px solid var(--border);border-radius:16px;padding:24px;width:100%;max-width:440px;position:relative;display:flex;flex-direction:column;gap:16px;max-height:90vh;overflow-y:auto}.modal-close{position:absolute;top:12px;right:12px;background:none;border:none;color:var(--muted);font-size:1.1rem;cursor:pointer;padding:4px 8px}.modal-head{display:flex;flex-direction:column;gap:6px}.price{font-size:1.8rem;font-weight:800}.price span{font-size:.9rem;font-weight:500;color:var(--muted)}.address-block{display:flex;gap:8px;align-items:center;background:var(--bg);border:1px solid var(--border);border-radius:10px;padding:8px 10px}.address{flex:1;font-size:.72rem;word-break:break-all;background:none;border:none;padding:0;color:#9ae6b4}.steps.small li{font-size:.88rem}.points-chip{background:var(--surface-2);border:1px solid var(--border);border-radius:999px;padding:4px 12px;font-size:.85rem;font-weight:700;white-space:nowrap}.filters{display:flex;gap:8px;flex-wrap:wrap}.filters select{flex:1;min-width:120px;text-transform:capitalize}.score{flex-direction:row;align-items:center;justify-content:space-between;padding:14px 20px}.big{font-size:1.6rem}button.puzzle{text-align:left;align-items:stretch;gap:8px;transition:border-color .15s,transform .05s}button.puzzle:hover{border-color:var(--accent)}button.puzzle:active{transform:translateY(1px)}button.puzzle strong{font-size:1.05rem}.nomargin{margin:0}.diff{font-size:.8rem;font-weight:600}.solved-tag{color:#22c55e;font-size:.8rem;font-weight:700}.badge.cat-crypto{color:#7dd3fc;border-color:#0369a1}.badge.cat-web{color:#f0abfc;border-color:#a21caf}.badge.cat-forensics{color:#fcd34d;border-color:#b45309}.badge.cat-reversing{color:#fca5a5;border-color:#b91c1c}.badge.cat-network{color:#86efac;border-color:#15803d}.badge.cat-misc{color:#c4b5fd;border-color:#6d28d9}.link{background:none;border:none;color:var(--accent);padding:4px 0;cursor:pointer;align-self:flex-start;font-size:.9rem}.artifact{background:#05090f;border:1px solid var(--border);border-radius:10px;padding:12px 14px;overflow-x:auto;font-family:ui-monospace,SF Mono,Menlo,Consolas,monospace;font-size:.85rem;white-space:pre-wrap;word-break:break-all;color:#9ae6b4}.hint-box{background:#1f1a0b;border:1px solid #a16207;border-radius:10px;padding:10px 12px;font-size:.88rem}.success{background:#0b2016;border:1px solid #22c55e88;border-radius:12px;padding:16px;display:flex;flex-direction:column;gap:8px}.wrong-msg{color:var(--danger);font-size:.85rem;margin:2px 0 0}.row.wrap{flex-wrap:wrap}.hero h2{font-size:1.35rem;letter-spacing:-.02em}.hero .row{margin-top:4px}.tiles{display:grid;grid-template-columns:repeat(4,1fr);gap:10px}.tile{background:var(--surface);border:1px solid var(--border);border-radius:12px;padding:14px 10px;display:flex;flex-direction:column;align-items:center;gap:3px;text-align:center}.tile-icon{font-size:1.1rem}.tile-value{font-size:1.35rem}.steps{margin:4px 0;padding-left:20px;display:flex;flex-direction:column;gap:6px}.steps li{line-height:1.4}@media (max-width: 480px){.tiles{grid-template-columns:repeat(2,1fr)}}input.shake{border-color:var(--danger);animation:shake .3s}@keyframes shake{0%,to{transform:translate(0)}25%{transform:translate(-5px)}75%{transform:translate(5px)}}