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90px}.challenge-layout[hidden]{display:none}.curriculum{border-right:1px solid var(--line);padding-right:28px}.path-label{font-size:10px;line-height:1.5;color:var(--muted);margin:30px 0 13px}.path-label:first-child{margin-top:6px}.challenge-link{display:grid;grid-template-columns:23px 1fr 14px;align-items:start;gap:8px;padding:11px 8px;border-left:2px solid transparent;color:var(--muted);font-size:11px;line-height:1.5}.challenge-link .number{font-size:10px;color:#74816d}.challenge-link[aria-current="true"]{border-color:var(--green);background:#b8ff4008;color:var(--text)}.challenge-link .completed-mark{color:var(--green)}.challenge-heading{display:flex;justify-content:space-between;gap:16px;align-items:center;margin-bottom:18px}.challenge-heading .eyebrow{margin:0}.difficulty{padding:4px 9px;border:1px solid var(--line);font-size:9px;text-transform:uppercase;letter-spacing:.12em}.workbench>h2{font-size:clamp(30px,3.5vw,46px);margin-bottom:23px}.workbench>p.muted{max-width:660px;font-size:12px;line-height:1.9}.goal-box{border:1px solid #668832;background:#b8ff4006;padding:19px 22px;margin:25px 0 32px}.goal-box .meta-label{color:var(--green);margin-bottom:8px}.goal-box p{font-size:12px;margin:0}.editor-heading{display:flex;justify-content:space-between;gap:12px;align-items:baseline}.editor-heading h3{font-size:16px}.editor-heading>span{font-size:10px;color:var(--muted)}.editor-help{color:var(--muted);font-size:10px;line-height:1.8;margin:12px 0 22px}.editable-bytes{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:15px;margin-bottom:27px}.editable-byte{border:1px solid var(--line);padding:13px;min-width:0}.editable-byte.edited{border-color:#6c9840}.byte-head{display:flex;justify-content:space-between;gap:8px;margin-bottom:9px;font-size:9px;color:var(--muted)}.byte-head strong{color:var(--text);font-size:11px;font-weight:normal}.challenge-bits{display:grid;grid-template-columns:repeat(8,minmax(0,1fr));gap:3px}.challenge-bit{border:1px solid var(--line);min-height:43px;min-width:0;padding:4px;background:#070c07;color:#7d8a73;font-size:18px}.challenge-bit[aria-pressed="true"]{color:var(--green);background:#b8ff400b}.challenge-bit.changed{border-color:var(--green)}.challenge-bit:hover{border-color:var(--green)}#binary-source{width:100%;display:block;border:1px solid var(--line);background:#060a06;color:var(--text);padding:17px;font:11px/1.9 var(--mono);resize:vertical;border-radius:0;min-height:190px;max-height:450px;white-space:pre;overflow:auto;tab-size:2}.challenge-controls{gap:10px;align-items:stretch}.challenge-controls .small-button{display:flex;align-items:center;justify-content:center;gap:7px;font-size:10px}.challenge-controls .button{font-size:10px}.hints{color:var(--code);font-size:11px;padding-left:24px;margin:24px 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.pass{color:var(--green)}.goal-checks .fail{color:#ffb09b}.explanation,.instruction-map{border-block:1px solid var(--line);padding:18px 0;font-size:11px}.instruction-map{border-top:0}.explanation summary,.instruction-map summary{cursor:pointer;color:var(--text);font-size:12px}.explanation p{margin:18px 0 0;color:var(--muted);line-height:1.9}.explanation .inline-link{margin-top:18px;font-size:10px}.visual-explanation{font-size:12px;line-height:1.8;margin-top:24px;padding:16px 18px;border:1px solid var(--line);background:var(--panel);color:var(--green);overflow-wrap:anywhere}.instruction-map ol{list-style:none;margin:20px 0 0;padding:0}.instruction-map li{display:grid;grid-template-columns:48px minmax(0,1fr);gap:10px;margin:15px 0;line-height:1.8}.instruction-map .instruction-offset{color:var(--green)}.instruction-map small{display:block;color:var(--muted);font-size:10px}.model-note{font-size:10px;color:var(--muted);margin:27px 0 0;line-height:1.9}.challenge-footer{padding:28px 0;border-top:1px solid var(--line);display:flex;justify-content:space-between;gap:24px;font-size:9px;color:var(--muted)}#load-status{color:var(--muted);font-size:11px;margin:25px 0}.challenge-layout~#load-status{margin:0}@keyframes success-signal{0%{box-shadow:0 0 0 0 #b8ff4060}100%{box-shadow:0 0 0 15px #b8ff4000}}@media(min-width:1000px){.curriculum{align-self:start;position:sticky;top:25px;max-height:calc(100vh - 50px);overflow:auto}}@media(max-width:900px){.challenge-layout{grid-template-columns:220px minmax(0,1fr);gap:27px}.curriculum{padding-right:14px}.editable-bytes{grid-template-columns:1fr}.challenge-intro{gap:30px}.progress-instrument{padding-left:24px}}@media(max-width:650px){.wrap{width:calc(100% - 32px)}.header{padding:20px 0;gap:18px;align-items:start}.header .brand{font-size:20px;flex-wrap:wrap;gap:4px}.header .version{margin-left:0;flex-basis:100%}.header nav{gap:8px;flex-wrap:wrap;justify-content:end;font-size:10px;max-width:170px}.header nav a:first-child{display:inline}.challenge-intro{grid-template-columns:1fr;padding:45px 0 34px;gap:28px}.challenge-intro h1{font-size:54px}.challenge-intro .eyebrow{margin-bottom:20px}.intro-copy{font-size:11px}.progress-instrument{border-left:0;border-top:1px solid var(--line);padding:22px 0 0}.progress-instrument strong{font-size:42px}.progress-instrument .meta-label{font-size:9px}.privacy-note{max-width:none}.challenge-layout{grid-template-columns:1fr;gap:30px;padding-top:15px}.curriculum{border-right:0;border-bottom:1px solid var(--line);padding:0 0 20px;max-height:200px;overflow:auto}.curriculum nav{display:grid;grid-template-columns:1fr 1fr;gap:0 8px}.path-label{grid-column:1/-1;margin:20px 0 8px}.challenge-link{font-size:10px;padding:8px 3px;grid-template-columns:18px 1fr 10px;gap:4px}.challenge-heading{margin-bottom:17px}.workbench>h2{font-size:33px}.editable-bytes{grid-template-columns:1fr}.goal-box{padding:16px}.challenge-controls .button{width:100%}.challenge-controls .small-button{flex:1;min-height:44px}.editor-heading{flex-wrap:wrap}#binary-source{font-size:10px;padding:12px}.result-panel{padding:17px}.challenge-footer{flex-wrap:wrap;gap:12px}.challenge-footer span{flex-basis:100%;order:3}}@media(prefers-reduced-motion:reduce){.result-panel.success.flash{animation:none}html{scroll-behavior:auto}}