@import url('https://fonts.googleapis.com/css2?family=DM+Sans:wght@400;500;600;700&family=Manrope:wght@400;500;600;700;800&family=IBM+Plex+Mono:wght@400;500&display=swap');
:root{color-scheme:light;--ink:#263b36;--muted:#7b827a;--yellow:#ffcf39;--paper:#fffef9;--line:#e9e9df;--font-body:'DM Sans',sans-serif;--font-display:'Manrope',sans-serif;--font-mono:'IBM Plex Mono',monospace}
*{box-sizing:border-box}body{margin:0;background:var(--paper);color:var(--ink);font:14px var(--font-body);line-height:1.6}button,input,select,textarea{font:inherit}button,select{cursor:pointer}button{border:0}button:disabled{cursor:not-allowed;opacity:.45}button,a,input,select,textarea{outline-offset:4px}button:focus-visible,a:focus-visible{outline:3px solid #bf8b00}a{color:inherit;text-decoration:none}[hidden]{display:none!important}.skip-link{position:fixed;top:-60px;left:16px;background:white;padding:10px;z-index:10}.skip-link:focus{top:10px}.site-header{height:88px;padding:0 5%;display:flex;align-items:center;gap:30px;border-bottom:1px solid var(--line);background:#fff}.brand{display:flex;align-items:center;gap:11px;font:800 26px var(--font-display);letter-spacing:-1px}.brand img{border-radius:13px}.brand-dot{color:#e8b314}.header-note{font-size:12px;color:var(--muted);border-left:1px solid var(--line);padding-left:26px}.profile-button{margin-left:auto;display:flex;align-items:center;gap:10px;background:white;border:1px solid var(--line);border-radius:28px;padding:6px 13px 6px 6px;color:var(--ink);font-weight:600;font-size:12px}.avatar{background:#f4f0d8;width:30px;height:30px;display:grid;place-items:center;border-radius:50%;font-weight:700}.profile-button.verified .avatar{background:#e7f2e5;color:#386b4c}.page-shell{max-width:1560px;margin:auto;padding:0 5%}.intro{display:flex;align-items:center;justify-content:space-between;gap:30px;padding:43px 0 35px}.eyebrow{font-size:9px;letter-spacing:1.8px;font-weight:700;color:#7b826f}.tiny-foot{color:#c59619;margin-right:6px;font-size:14px}h1{margin:7px 0 6px;font:800 clamp(30px,3.7vw,46px)/1.2 var(--font-display);letter-spacing:-1.8px}h1 span{color:#edba22}.intro p{color:var(--muted);margin:0;font-size:13px}.progress-card{width:245px;flex-shrink:0;padding-top:12px}.progress-label{display:flex;justify-content:space-between;font-size:11px}.progress-label strong{font-weight:600}.progress-track{height:6px;border-radius:6px;background:#eeeee2;margin:9px 0 8px;overflow:hidden}.progress-track span{display:block;height:100%;width:0;background:#e8bb26;border-radius:6px;transition:width .3s}.progress-card>span{color:var(--muted);font-size:10px}.workbench{border:1px solid #dedfd3;border-radius:13px;background:white;overflow:hidden;box-shadow:0 12px 35px #36423205}.exercise-toolbar{display:flex;align-items:center;padding:16px 21px;gap:15px;border-bottom:1px solid var(--line);min-height:73px}.exercise-picker{display:flex;align-items:center;gap:13px}.exercise-picker label{font-size:9px;letter-spacing:1.2px;color:#8b8f80;font-weight:700}.exercise-picker select{background:#f8f8f2;border:1px solid var(--line);border-radius:6px;max-width:260px;min-width:190px;padding:8px 28px 8px 10px;color:var(--ink);font-size:12px;font-weight:600}.topic-label{font-size:10px;color:#8b8f80}.exercise-navigation{display:flex;align-items:center;gap:12px;margin-left:auto}.exercise-navigation>span{font:10px var(--font-mono);color:#7e8579}.icon-button{border:1px solid var(--line);background:white;color:var(--ink);width:28px;height:28px;border-radius:6px}.icon-button:hover{background:#fff7d6}.split-panes{display:grid;grid-template-columns:1fr 1fr}.exercise-pane{min-width:0;border-right:1px solid var(--line);display:flex;flex-direction:column}.pane-heading{height:48px;border-bottom:1px solid var(--line);padding:0 20px;display:flex;align-items:center;justify-content:space-between}.file-tab{font:11px var(--font-mono);display:flex;align-items:center;gap:9px}.file-dot{width:6px;height:6px;background:#e0b42a;border-radius:50%}.editable-badge,.readonly-label{font-size:8px;color:#8c9282;letter-spacing:1px}.editable-badge{background:#f6f6ec;border-radius:3px;padding:2px 5px}.editor-shell{display:flex;min-height:330px;flex:1;padding:22px 0 18px;background:#fff}.line-numbers{font:12px/1.9 var(--font-mono);color:#c2c7bc;text-align:right;flex:0 0 45px;margin:0;padding-right:13px;overflow:hidden;user-select:none;height:316px}#editor{resize:vertical;display:block;width:100%;min-height:300px;height:316px;flex:1;min-width:0;border:0;border-radius:0;padding:0 18px 8px 0;margin:0;outline:none;box-shadow:none!important;background:transparent;color:#354c41;font:12px/1.9 var(--font-mono);tab-size:4;white-space:pre;overflow:auto}#editor:focus-visible{outline:2px solid #e5ba33;outline-offset:-2px}.editor-actions{border-top:1px solid var(--line);padding:13px 16px;display:flex;align-items:center;gap:10px;min-height:64px}.editor-helpers{display:flex;gap:10px}.text-button{background:none;color:#566453;padding:3px 0;font-size:11px;white-space:normal}.text-button:hover{text-decoration:underline}.muted{color:#929789}.save-state{font-size:9px;color:#8a9482;margin-left:auto;white-space:nowrap}.run-button{display:flex;align-items:center;gap:8px;background:var(--yellow);padding:10px 14px;color:#35412b;border-radius:7px;font-size:11px;font-weight:700;white-space:nowrap;box-shadow:0 2px 0 #dcb02a}.run-button:hover{background:#f4c326}.run-button kbd{font:9px var(--font-body);opacity:.55;margin-left:4px}.hint-box{background:#fffae7;margin:0 16px 14px;padding:14px 16px;font-size:12px;border-left:3px solid #f0cb49;border-radius:5px}.hint-box p{white-space:pre-wrap;margin:5px 0 0}.solution-pane{background:#fafbf5;position:relative;min-width:0}.solution-pane .pane-heading{background:#f7f8f1}.solution-icon{color:#a5ad95;font-size:18px}.solution-cover{min-height:394px;display:flex;flex-direction:column;align-items:center;justify-content:center;padding:25px;text-align:center}.solution-illustration{position:relative;width:185px;height:140px;display:grid;place-items:center;margin-bottom:12px}.solution-illustration img{z-index:1;transform:rotate(-7deg);border-radius:32px;box-shadow:0 9px 0 #edeedc70}.orbit{position:absolute;border:1px dashed #dce0cd;border-radius:50%;width:177px;height:105px;transform:rotate(-25deg)}.orbit-two{transform:rotate(40deg);width:142px;height:145px;border-color:#e7dcae}.sparkle{position:absolute;color:#b1b89d;right:-3px;top:5px;font-size:24px}.solution-cover h2{font:700 21px var(--font-display);letter-spacing:-.6px;margin:10px 0}.solution-cover p{font-size:12px;color:#85907c;line-height:1.8;margin:0}.reveal-button{display:flex;gap:18px;align-items:center;background:#fff;border:1px solid #dfe4d5;border-radius:7px;padding:9px 17px;margin:19px 0 14px;font-weight:600;color:#54634b;font-size:11px}.reveal-button:hover{border-color:#c4ad48;background:#fffdf0}.solution-cover small{color:#a0a68f;font-size:9px}.solution-content{min-height:394px;padding:14px 20px}.solution-notice{display:flex;align-items:center;justify-content:space-between;gap:10px;font-size:10px;color:#819075;border-bottom:1px solid #e4e8d9;padding-bottom:10px}.solution-content pre{white-space:pre;overflow:auto;max-height:350px;font:12px/1.9 var(--font-mono);margin:20px 0;color:#456142}.solution-content code{font:inherit}.results-panel{border-top:1px solid #dedfd3;background:#f9faf5}.results-heading{display:flex;justify-content:space-between;align-items:center;padding:16px 21px 0}.results-heading>div{display:flex;align-items:center;gap:10px}.terminal-symbol{font:700 14px var(--font-mono);color:#7b8775}.results-heading h2{font-size:11px;font-weight:600;margin:0}.result-badge{font-size:9px;color:#8b9581;padding:3px 9px;background:#eef1e8;border-radius:4px}.result-badge.passed{color:#347047;background:#e2efdc}.result-badge.failed{color:#a64d35;background:#fce9df}.result-badge.running{color:#92751b;background:#fff2bb}#duration{font:9px var(--font-mono);color:#879079}#output{margin:0;padding:15px 22px 20px;color:#77836d;font:11px/1.85 var(--font-mono);white-space:pre-wrap;overflow-wrap:anywhere;max-height:290px;overflow:auto;min-height:90px}.results-footer{display:flex;justify-content:space-between;align-items:center;gap:16px;padding:12px 20px;border-top:1px solid #e8ebdf;background:#fff}#result-help{font-size:10px;color:#939b85;display:flex;align-items:center;gap:7px}.yellow-dot{width:5px;height:5px;border-radius:50%;background:#ddbc46;flex-shrink:0}.next-button{display:flex;gap:20px;align-items:center;background:#f6f7ed;border:1px solid #e3e7d8;border-radius:6px;padding:9px 15px;font-size:11px;font-weight:600;color:#556545;white-space:nowrap}.next-button:enabled{background:#fff1af;border-color:#efd169;color:#5b531f}.site-footer{display:flex;justify-content:space-between;gap:25px;padding:23px 0 28px;color:#9ba18e;font-size:9px}.site-footer>span>span{color:#d3b452;margin-right:6px}.site-footer a:hover{color:var(--ink)}.notice{background:#fff0d4;color:#754d19;border:1px solid #ecd2a0;border-radius:7px;padding:12px 16px;margin-bottom:16px;font-size:12px}dialog{width:430px;max-width:calc(100% - 32px);padding:34px;border:1px solid var(--line);border-radius:17px;color:var(--ink);box-shadow:0 25px 120px #14251e30;background:var(--paper)}dialog::backdrop{background:#263b3677;backdrop-filter:blur(4px)}.dialog-close{position:absolute;right:16px;top:13px;background:none;font-size:24px;color:#818a76}.dialog-close:hover{color:var(--ink)}dialog>img{display:block;margin-bottom:20px}dialog h2{font:800 24px/1.3 var(--font-display);letter-spacing:-.7px;margin:8px 0 12px}dialog p{font-size:12px;color:#7b8671}.local-note{background:#fff3c5;border-radius:7px;padding:12px;font-size:11px;color:#7e6b30;margin:17px 0 20px}dialog label{font-size:11px;display:block;margin-bottom:7px;font-weight:600}dialog input{border:1px solid #dce0ce;border-radius:7px;width:100%;padding:12px;color:var(--ink);background:white;margin-bottom:12px}.primary-button{background:var(--yellow);color:#454b29;border-radius:7px;padding:12px 17px;font-size:12px;font-weight:600;display:flex;align-items:center;justify-content:space-between;gap:8px}form .primary-button{width:100%}.secondary-button{background:#edf0e5;border:1px solid #dde3d2;border-radius:7px;padding:10px 14px;color:#56634b;font-size:12px}.login-message{min-height:20px}.login-message.error{color:#a14531}#otp{font:22px var(--font-mono);letter-spacing:10px;text-align:center}.export-button{border-top:1px solid var(--line);padding-top:15px;width:100%;text-align:center;color:#859078}.dialog-actions{display:flex;justify-content:flex-end;gap:10px}.toast{position:fixed;bottom:25px;left:50%;transform:translateX(-50%);background:var(--ink);color:#fff8d1;box-shadow:0 7px 25px #0002;border-radius:8px;padding:12px 20px;font-size:12px;z-index:20}
@media(min-width:1500px){.editor-shell{min-height:390px}#editor,.line-numbers{height:370px}.solution-cover,.solution-content{min-height:454px}}@media(max-width:1100px){.header-note{display:none}.save-state{display:none}.run-button{margin-left:auto}.run-button kbd{display:none}.topic-label{display:none}.page-shell{padding:0 3%}.site-header{padding:0 3%}.editor-actions{padding:13px 12px}.editor-helpers{gap:9px}.pane-heading{padding:0 14px}.editable-badge{display:none}}
@media(max-width:700px){.site-header{height:72px}.brand{font-size:23px}.brand img{width:36px;height:36px}.profile-button{max-width:185px;font-size:10px;gap:6px}#username{overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.intro{padding:28px 5px 24px;display:block}h1{font-size:36px}.intro p{font-size:12px}.progress-card{width:100%;padding-top:22px}.progress-card>span{display:none}.page-shell{padding:0 12px}.exercise-toolbar{padding:12px;gap:8px}.exercise-picker{display:block;min-width:0}.exercise-picker label{display:block;font-size:8px;margin-bottom:5px}.exercise-picker select{max-width:195px;min-width:160px;font-size:11px}.exercise-navigation{gap:7px}.exercise-navigation>span{font-size:9px}.icon-button{width:25px;height:25px}.split-panes{grid-template-columns:1fr}.exercise-pane{border-right:0}.solution-pane{border-top:1px solid var(--line)}.solution-cover{min-height:295px;padding:22px}.solution-illustration{height:105px;margin-bottom:8px;transform:scale(.8)}.solution-cover h2{font-size:20px}.solution-cover small{display:none}.solution-cover br{display:none}.solution-cover p{max-width:245px}.reveal-button{margin-bottom:0}.solution-content{min-height:220px}.solution-content pre{max-height:300px}.editor-shell{min-height:300px}#editor,.line-numbers{height:300px}.editable-badge{display:inline}.editor-actions{padding:13px}.save-state{display:block;font-size:8px}.run-button{padding:10px 12px;font-size:10px}.results-footer{padding:12px;align-items:flex-start}#result-help{font-size:9px;line-height:1.6}.next-button{gap:10px;padding:8px 10px;font-size:10px}.site-footer{display:block;text-align:center;padding:22px 12px}.site-footer a{display:block;margin-top:8px}.result-badge{font-size:8px}dialog{padding:28px}.dialog-actions{flex-wrap:wrap}}
@media(prefers-reduced-motion:reduce){*{transition:none!important;animation:none!important}}
/* Scope heading typography above EmeraldCSS's main h1 selector. */
.intro h1{font:800 clamp(30px,3.7vw,46px)/1.2 var(--font-display);color:var(--ink);letter-spacing:-1.8px;margin:7px 0 6px}.solution-cover h2{color:var(--ink)}.intro p,.header-note,.progress-card>span{color:#697363}#output{color:#5c6c53}#result-help,.site-footer{color:#6b775e}.solution-cover p{color:#69775e}
@media(max-width:700px){.intro h1{font-size:36px}}