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*{box-sizing:border-box}body{margin:0;min-height:100vh}button,input,textarea{font:inherit}button{cursor:pointer}a{color:inherit;text-decoration:none}a:hover{text-decoration:underline}
.challenge-header{height:64px;background:#23252c;border-bottom:1px solid #363840;display:flex;align-items:center;justify-content:space-between;gap:20px;padding:0 clamp(16px,3vw,40px)}
.brand{display:flex;align-items:center;gap:11px;font-size:.95rem;font-weight:800;line-height:1.05;white-space:nowrap}.brand small{display:block;color:#c6a767;font-size:.65rem;letter-spacing:.1em;text-transform:uppercase;margin-top:4px}.brand-mark{width:34px;height:34px;display:grid;place-items:center;border-radius:10px;background:#f6b73c;color:#29231d;font-size:1.4rem}.challenge-header nav{display:flex;gap:25px;color:#c3c7d0;font-size:.82rem;font-weight:700}
.workspace{display:grid;grid-template-columns:minmax(330px,43%) minmax(420px,1fr);gap:10px;padding:10px;min-height:calc(100vh - 64px)}.pane{background:#262830;border:1px solid #373a43;border-radius:9px;overflow:hidden}.pane-tab{background:#2d3038;border-bottom:1px solid #3a3d46;padding:13px 18px;font-size:.84rem;font-weight:750;color:#e6e8ed}.description{min-height:670px}.problem-copy{padding:28px clamp(20px,3vw,45px);max-width:780px}.problem-number{margin:0 0 8px;color:#c4a366;font-size:.77rem;font-weight:800;letter-spacing:.08em;text-transform:uppercase}.problem-copy h1{font-size:clamp(1.9rem,3vw,2.7rem);margin:0 0 13px;letter-spacing:-.04em}.badges{display:flex;gap:8px;margin-bottom:30px}.badges span{background:#3c4138;color:#b4e28c;font-size:.73rem;font-weight:800;border-radius:20px;padding:5px 10px}.badges span+span{background:#353b48;color:#b6cef8}.problem-copy p,.problem-copy li{color:#d4d7df;line-height:1.72;font-size:.95rem}.problem-copy code{background:#393c46;padding:2px 5px;border-radius:4px;color:#f6d49a}.problem-copy h2{font-size:1.1rem;margin:28px 0 8px}.problem-copy ol{padding-left:22px}.problem-copy li{padding-left:4px;margin:7px 0}.example{background:#30323a;border:1px solid #444751;border-radius:8px;padding:16px 18px;margin:24px 0}.example strong{font-size:.81rem}.example pre{background:#22242a;border-radius:5px;padding:14px;color:#eff2f8;line-height:1.7;margin-bottom:0}.lesson-note{font-size:.83rem!important;color:#aeb4c2!important}
.right-stack{display:grid;grid-template-rows:minmax(350px,1fr) minmax(150px,auto) auto;gap:10px;min-width:0}.language{float:right;color:#b9c2d4;font-weight:500}.editor-help{padding:16px 22px 8px;color:#bfc5d0;font-size:.83rem}.code-editor-wrap{display:grid;grid-template-columns:52px minmax(0,1fr);min-height:290px;height:clamp(290px,38vh,490px);background:#1d2028;border-top:1px solid #343844;border-bottom:1px solid #343844;margin:10px 0 0;overflow:hidden}.line-numbers,.code-editor{font:15px/25px ui-monospace,Consolas,monospace;tab-size:4;margin:0;padding:14px 0;white-space:pre;overflow:auto}.line-numbers{color:#7c8494;text-align:right;padding-right:13px;overflow:hidden;user-select:none;border-right:1px solid #343844}.code-editor{width:100%;height:100%;resize:none;border:0;outline:0;background:transparent;color:#e8f0fd;padding-left:16px;overflow-wrap:normal;white-space:pre;caret-color:#f6b73c}.code-editor:focus{box-shadow:inset 0 0 0 1px #7fb7e7}.editor-footer{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:14px 20px;color:#aeb5c1;font-size:.79rem}.run-button,.submit-row button{border:0;border-radius:6px;padding:10px 16px;background:#2b824e;color:#fff;font-weight:800;white-space:nowrap}.run-button:hover,.submit-row button:hover{background:#33985b}button:disabled{opacity:.55;cursor:wait}
.console pre{margin:0;min-height:76px;padding:16px 20px;color:#ebeff6;white-space:pre-wrap;font:14px/1.6 ui-monospace,Consolas,monospace}.test-result{margin:0 20px 16px;font-size:.82rem;color:#b5bac5}.test-result.passed{color:#96dbac}.test-result.needs-work{color:#efc789}
.submit{padding-bottom:18px}.submit>div,.submit form{padding:0 20px}.submit h2{font-size:1rem;margin:17px 0 4px}.submit p{font-size:.79rem;line-height:1.5;color:#b8bdc9;margin:4px 0 12px}.submit label{display:block;font-size:.79rem;font-weight:750;margin-bottom:7px}.submit label span{font-weight:500;color:#e8c078}.submit-row{display:flex;gap:9px}.submit-row input{flex:1;min-width:0;background:#1d2028;color:#fff;border:1px solid #555c68;border-radius:6px;padding:10px 12px}.submit-row input:focus{outline:2px solid #8cbfe4}.submit #submit-message{min-height:19px;margin-top:9px;color:#a9dfb9}.sr-only{position:absolute!important;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
@media(max-width:850px){.workspace{grid-template-columns:1fr}.description{min-height:0}.right-stack{grid-template-rows:auto}.challenge-header nav{gap:12px}}@media(max-width:500px){.challenge-header{padding:0 12px}.challenge-header nav{font-size:.7rem}.challenge-header nav a:last-child{display:none}.problem-copy{padding:23px 19px}.submit-row{flex-direction:column}.submit-row button{width:100%}}@media(max-width:400px){.homework-header nav a:first-child{display:none}}
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