/* Guided practice / the same smoked glass, with room to think. */
.problem-workspace{--practice-line:rgba(255,255,255,.12);--practice-soft:rgba(255,255,255,.045);max-width:1320px;margin:0 auto;padding-top:5px}
.problem-workspace *, .puzzle-guide *{box-sizing:border-box}
.problem-breadcrumb{display:flex;gap:16px;align-items:center;margin-bottom:30px;font-size:11px;color:var(--muted)}
.problem-breadcrumb .back-link{margin:0}.problem-breadcrumb>span{font-family:var(--mono);font-size:9px;letter-spacing:.09em;padding-left:16px;border-left:1px solid var(--practice-line)}
.problem-tutor-link{margin-left:auto;display:inline-flex;align-items:center;gap:7px;color:#d6d8dc}.problem-tutor-link svg{width:15px}
.problem-header{display:flex;align-items:flex-start;gap:24px;justify-content:space-between;margin-bottom:35px}
.problem-kicker{font-family:var(--mono,'JetBrains Mono',monospace);font-size:9px;font-weight:400;line-height:1.7;letter-spacing:.15em;color:#a2a5ae;text-transform:uppercase;display:block}
.problem-header h1{font-size:clamp(27px,3.2vw,44px);font-weight:500;line-height:1.14;letter-spacing:-1.6px;max-width:900px;margin:13px 0 20px}
.problem-meta{display:flex;flex-wrap:wrap;align-items:center;gap:12px;color:#acafb7;font-size:11px}.problem-meta>span+span:not(.problem-completed-label):before{content:'·';margin-right:12px;color:#666a74}.problem-meta .difficulty{font-size:10px}
.problem-completed-label{display:inline-flex;gap:6px;align-items:center}.problem-completed-label[hidden]{display:none}.problem-completed-label svg{width:13px}
.problem-save{flex-shrink:0;margin-top:17px;background:var(--practice-soft)!important;border:1px solid var(--practice-line)!important}.problem-save[aria-pressed=true]{background:#ffffff14!important;color:#fff}
.problem-path{margin-bottom:25px}.problem-steps{display:grid;grid-template-columns:repeat(4,1fr);gap:7px}
.problem-steps>button{appearance:none;text-align:left;display:flex;align-items:center;gap:11px;background:transparent;padding:14px 12px;color:#91959e;border:1px solid transparent;border-radius:12px;font:500 12px var(--font);cursor:pointer;transition:background .2s,color .2s,border-color .2s}
.problem-step-number{display:flex;justify-content:center;align-items:center;width:28px;height:28px;flex-shrink:0;background:#ffffff03;border:1px solid #ffffff18;border-radius:50%;font-family:var(--mono);font-size:10px;color:#9b9fa8}.problem-step-number svg{width:13px}
.problem-steps>button:hover{background:#ffffff05;color:#e4e5e7}.problem-steps>button.is-current{background:linear-gradient(135deg,#ffffff0b,#ffffff04);border-color:#ffffff18;color:#eff0f1}.problem-steps>button.is-current .problem-step-number{background:#e1e3e6;color:#22252a;border-color:#e1e3e6}.problem-steps>button.is-done:not(.is-current) .problem-step-number{border-color:#ffffff36;color:#e0e2e5}
.problem-progress{height:2px;margin-top:17px;background:#ffffff09;border-radius:3px;overflow:hidden}.problem-progress>span{height:100%;display:block;width:0;background:linear-gradient(90deg,#7e858f,#d7dbe2);transition:width .45s ease}
.problem-layout{display:grid;grid-template-columns:minmax(0,1fr) 245px;gap:24px;align-items:start}.problem-pane.panel{padding:32px;min-width:0;border-color:#ffffff17;background:linear-gradient(135deg,#ffffff06,#ffffff02);box-shadow:inset 0 1px 0 #ffffff04;scroll-margin-top:100px}
.problem-pane-heading{margin-bottom:27px}.problem-pane-heading h2{font-size:31px;line-height:1.19;letter-spacing:-1.1px;font-weight:500;margin:12px 0}.problem-pane-heading h2:focus{outline:none}.problem-pane-heading>p{color:#a7aab2;font-size:12px;line-height:1.85;max-width:580px}
.problem-idea{padding:22px 24px;background:#ffffff04;border:1px solid #ffffff0c;border-radius:12px}.problem-idea>span{display:flex;align-items:center;gap:8px;color:#aeb2ba;font:9px var(--mono);letter-spacing:.1em}.problem-idea svg{width:13px}.problem-idea>p{font-size:17px;line-height:1.75;margin:14px 0 0;color:#d8dade;letter-spacing:-.2px}
.problem-mini-flow{display:flex;align-items:center;gap:12px;padding:28px 0}.problem-mini-flow>div{flex:1;min-width:0;display:flex;flex-direction:column;align-items:center;text-align:center;padding:18px 6px;border:1px solid #ffffff0d;border-radius:12px;background:#ffffff02}.problem-mini-flow>div>span{width:31px;height:31px;display:grid;place-items:center;border:1px solid #ffffff18;border-radius:9px;color:#b8bec7;margin-bottom:12px}.problem-mini-flow svg{width:16px;height:16px}.problem-mini-flow strong{font-weight:500;font-size:11px;line-height:1.5}.problem-mini-flow small{color:#858a95;font-size:9px;line-height:1.5;margin-top:5px}.problem-mini-flow>b{color:#7d838f;font-weight:400}
.problem-mission{padding:22px 0 25px;border-top:1px solid #ffffff0c}.problem-mission h3{font-size:18px;font-weight:500;line-height:1.6;margin:9px 0}.problem-mission>p{font-size:12px;color:#a6abb4;line-height:1.85}
.problem-term{width:100%;appearance:none;background:#ffffff03;border:1px solid #ffffff12;color:#d2d5db;border-radius:10px;padding:14px 16px;display:flex;align-items:center;justify-content:space-between;gap:12px;cursor:pointer}.problem-term>span{display:flex;align-items:center;gap:9px;font-size:11px}.problem-term>span+span{font-size:9px;color:#969ca6;flex-shrink:0}.problem-term svg{width:14px}.problem-term-meaning{margin:0;padding:16px;font-size:12px;color:#b7bcc6;background:#ffffff04;border:1px solid #ffffff0e;border-top:0;line-height:1.85;border-radius:0 0 10px 10px}
.problem-pane-footer{display:flex;gap:14px;align-items:center;justify-content:space-between;margin-top:30px;border-top:1px solid #ffffff0c;padding-top:22px}.problem-pane-footer>span{font-size:10px;color:#858c97}.problem-pane-footer .button{min-height:39px;white-space:normal}
.problem-sidebar{position:sticky;top:100px;display:flex;flex-direction:column;gap:13px}.problem-coach.panel{padding:23px;background:linear-gradient(145deg,#ffffff08,#ffffff02);border-color:#ffffff15}.problem-coach-icon{width:43px;height:43px;margin:29px 0 18px;display:grid;place-items:center;border:1px solid #ffffff20;border-radius:50%;color:#bdc4ce;background:#ffffff04}.problem-coach-icon svg{width:21px;height:21px}.problem-coach h2{font-size:23px;line-height:1.25;letter-spacing:-.7px;font-weight:500;margin-bottom:17px}.problem-coach>p{color:#a7aeb9;font-size:11px;line-height:1.9;margin-bottom:20px}.problem-coach .button{font-size:10px;width:100%;justify-content:center;background:#ffffff05!important}.problem-coach>a{display:flex;align-items:center;gap:9px;font-size:10px;margin-top:22px;color:#a8b0bc}.problem-coach>a svg{width:12px}.problem-coach #problem-hint-text:not(:empty){border:1px solid #ffffff13;border-radius:9px;margin-top:15px;padding:13px;background:#ffffff04}.problem-coach #problem-hint-text>span{font:8px var(--mono);letter-spacing:.08em;color:#8e98a7}.problem-coach #problem-hint-text>p{font-size:11px;line-height:1.8;color:#c6ccd5;margin:9px 0 0}
.problem-reference{border:1px solid #ffffff10;border-radius:10px;background:#ffffff02}.problem-reference summary{font-size:10px;color:#b6bcc6;padding:15px;cursor:pointer;line-height:1.6}.problem-reference>p{font-size:11px;color:#929ba9;line-height:1.85;padding:0 15px 16px;margin:0}.problem-local-caption{font-size:9px;line-height:1.9;color:#8d95a2;margin:0 3px}
.problem-file-tabs{display:flex;gap:5px;border-bottom:1px solid #ffffff15;overflow-x:auto;padding-bottom:9px}.problem-file-tabs button{flex-shrink:0;display:flex;align-items:center;gap:7px;padding:9px 12px;color:#929dab;font:10px var(--mono);background:transparent;border:1px solid transparent;border-radius:7px;cursor:pointer}.problem-file-tabs svg{width:13px}.problem-file-tabs button[aria-selected=true]{color:#e4e7eb;background:#ffffff07;border-color:#ffffff1b}
.problem-evidence{margin-top:16px;background:#0d0f13;border:1px solid #ffffff13;border-radius:11px;max-height:430px;overflow:auto;padding-bottom:10px;scrollbar-width:thin;scrollbar-color:#42464e transparent}.problem-evidence-caption{display:flex;justify-content:space-between;gap:12px;padding:15px 18px 13px;margin-bottom:5px;border-bottom:1px solid #ffffff0c;font:8px var(--mono);color:#7f899a;letter-spacing:.08em;white-space:nowrap}
.problem-line{display:flex;gap:15px;align-items:flex-start;appearance:none;text-align:left;width:100%;padding:9px 14px;border:0;border-left:2px solid transparent;background:none;color:#c0c9d5;cursor:pointer;font:11px/1.75 var(--mono);min-height:35px;transition:background .18s}.problem-line>span{width:19px;flex-shrink:0;color:#667082;text-align:right;font-size:10px}.problem-line code{white-space:pre-wrap;overflow-wrap:anywhere;font:inherit;flex:1;min-width:0;color:inherit;background:none;padding:0}.problem-line>i{color:#727e90;opacity:0;flex-shrink:0}.problem-line svg{width:12px;height:12px}.problem-line:hover{background:#ffffff08}.problem-line:hover>i,.problem-line.is-pinned>i{opacity:1}.problem-line.is-pinned{background:#c9d4e20e;border-left-color:#b3c1d3;color:#e0e6ef}.problem-line:disabled{cursor:default;opacity:.5}
.problem-pinned{padding:18px 0;display:flex;align-items:flex-start;gap:10px;color:#9ba7b9;font-size:11px;line-height:1.85}.problem-pinned>svg{width:17px;flex-shrink:0;margin-top:2px}.problem-pinned strong{color:#c5cfdd;font-size:11px;font-weight:500}.problem-pinned p{font:10px/1.8 var(--mono);color:#a6b2c3;overflow-wrap:anywhere;margin:6px 0}.problem-pinned small{font-size:9px;color:#8a95a6}
.problem-notes,.problem-editor,.problem-guidance{border:1px solid #ffffff13;border-radius:11px;margin-top:14px;overflow:hidden}.problem-notes>summary,.problem-editor>summary,.problem-guidance>summary{display:flex;align-items:center;gap:9px;padding:15px 17px;cursor:pointer;color:#b0bac8;font-size:11px;background:#ffffff02;list-style:none}.problem-notes>summary:after,.problem-editor>summary:after,.problem-guidance>summary:after{content:'+';margin-left:auto;color:#7d8a9d}.problem-notes[open]>summary:after,.problem-editor[open]>summary:after,.problem-guidance[open]>summary:after{content:'−'}.problem-notes>summary svg,.problem-editor>summary svg,.problem-guidance>summary svg{width:14px}.problem-notes summary>span,.problem-editor summary>span{margin-left:auto;color:#7c899b;font-size:9px}.problem-notes summary>span:after,.problem-editor summary>span:after{content:''}.problem-notes .input{display:block;min-height:100px;resize:vertical;border:0;border-radius:0;background:#0f1217;padding:16px;font-size:12px;line-height:1.8}.problem-editor>p,.problem-guidance>p{padding:0 16px;color:#9aa7b9;line-height:1.8;font-size:10px}.problem-editor textarea.input{display:block;border-left:0;border-right:0;border-radius:0;min-height:200px;resize:vertical;background:#0c1016;padding:16px;font:11px/1.8 var(--mono);tab-size:4}.problem-editor>div{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:12px 15px;font-size:9px;color:#7f8fa5}.problem-editor .button{font-size:9px;min-height:31px}.problem-guidance pre{max-height:400px;overflow:auto;white-space:pre-wrap;overflow-wrap:anywhere;font:10px/1.8 var(--mono);padding:15px;color:#b4c2d4;background:#0c1015;margin:0}
.problem-experiment{padding:23px;background:#ffffff03;border:1px solid #ffffff12;border-radius:13px}.problem-experiment-label{display:flex;align-items:center;justify-content:space-between;gap:15px;margin-bottom:22px;color:#8693a6;font:8px var(--mono);letter-spacing:.09em}.problem-experiment-label>span:first-child{display:inline-flex;align-items:center;gap:8px}.problem-experiment-label svg{width:13px}.problem-experiment>h3{font-size:21px;line-height:1.4;letter-spacing:-.5px;font-weight:500;margin:0 0 10px}.problem-experiment>p{font-size:11px;line-height:1.8;color:#9eabbc;margin:0}.problem-model-controls{margin:25px 0 20px}.problem-control-label{display:flex;justify-content:space-between;gap:16px;font-size:10px;color:#b3bfce;margin:15px 0 11px}.problem-control-label output{font-family:var(--mono);color:#e1e6ee}.problem-model-controls input.input,.problem-model-controls select.input{min-height:43px;background:#0e1218!important;border-color:#ffffff19!important;color:#d3dce9;font-size:11px;max-width:100%;width:100%}.problem-code{font-family:var(--mono)!important}.problem-model-controls input[type=range]{width:100%;accent-color:#c8d1de;cursor:pointer;margin:11px 0 19px}
.problem-presets{display:flex;gap:8px;flex-wrap:wrap;margin-top:10px}.problem-presets>button{appearance:none;background:#ffffff03;border:1px solid #ffffff16;border-radius:6px;padding:7px 10px;font-size:9px;font-family:var(--font);color:#a4b2c5;cursor:pointer}.problem-presets>button:hover{color:#e4ecf7;background:#ffffff09}
.problem-switch{display:flex;align-items:center;gap:11px;cursor:pointer;color:#bbc7d6;font-size:11px;line-height:1.6;padding:18px 0 0;position:relative}.problem-switch>input{position:absolute;left:0;top:21px;width:34px;height:20px;opacity:0}.problem-switch-track{width:34px;height:20px;border:1px solid #ffffff28;border-radius:20px;background:#ffffff05;position:relative;flex-shrink:0;transition:.2s}.problem-switch-track:after{content:'';position:absolute;width:12px;height:12px;background:#758094;border-radius:50%;top:3px;left:3px;transition:.2s}.problem-switch>input:checked+.problem-switch-track{border-color:#d5dce650;background:#d5dce61c}.problem-switch>input:checked+.problem-switch-track:after{background:#d4dfed;transform:translateX(14px)}.problem-switch>input:focus-visible+.problem-switch-track{outline:2px solid #d4dfed;outline-offset:4px}
.problem-model-result{border-top:1px solid #ffffff13;margin-top:22px;padding-top:20px;color:#a4b1c3;font-size:11px;line-height:1.85}.problem-model-result>p{margin:10px 0 15px}.problem-result-title{display:flex;align-items:center;gap:9px;flex-wrap:wrap;color:#d3dce9}.problem-result-title>svg{width:17px}.problem-result-title>strong{font-size:13px;font-weight:500}.problem-result-title>span{font:7px var(--mono);letter-spacing:.08em;margin-left:auto;color:#7c8da4}.problem-model-result pre,.problem-cipher-input{background:#0b0f15;padding:16px;border:1px solid #ffffff0e;border-radius:8px;white-space:pre-wrap;overflow-wrap:anywhere;color:#b4c6df;font:10px/1.85 var(--mono);margin:0}.problem-model-result ul{list-style:none;padding:0;margin:13px 0 0}.problem-model-result li{display:flex;align-items:center;gap:9px;border-top:1px solid #ffffff0a;padding:8px 0;font-family:var(--mono);font-size:10px}.problem-model-result li svg{width:12px}.problem-model-result.model-protected{border-top-color:#cbd8e333}
.problem-buffer{display:grid;grid-template-columns:repeat(12,1fr);gap:4px;margin-top:10px}.problem-buffer>span{height:29px;border:1px solid #ffffff18;background:#ffffff03;border-radius:3px;position:relative}.problem-buffer>span.buffer-filled{background:#b4c9e433;border-color:#b4c9e455}.problem-buffer>span.buffer-overflow{background:repeating-linear-gradient(45deg,#b6bec833,#b6bec833 3px,#ffffff04 3px,#ffffff04 7px);border-color:#d3dce780}.problem-buffer>span.buffer-boundary:before{content:'';position:absolute;left:-4px;top:-8px;bottom:-8px;width:1px;background:#d3dce7aa}.problem-buffer-label{display:flex;justify-content:space-between;margin-top:12px;color:#7d91ac;font:8px var(--mono)}.problem-buffer-label>span:nth-child(2){margin-left:20%}.problem-log-bars{display:flex;flex-direction:column;gap:12px;margin-bottom:25px}.problem-log-bars>div{display:flex;gap:12px;align-items:center}.problem-log-bars code{color:#9fb2cc;font:9px var(--mono);width:100px;flex-shrink:0;background:none;padding:0}.problem-log-bars span{height:5px;max-width:var(--size);flex:1;background:linear-gradient(90deg,#8f9fb54d,#c5d4e777);border-radius:3px}.problem-log-bars b{font:9px var(--mono);color:#a5b9d4}
.problem-story-rail{display:flex;gap:7px;margin:20px 0}.problem-story-rail>button{flex:1;text-align:left;appearance:none;border:1px solid #ffffff15;background:#ffffff02;color:#98aac2;font:10px var(--font);padding:12px;border-radius:8px;cursor:pointer;line-height:1.7}.problem-story-rail>button>span{display:block;font:8px var(--mono);margin-bottom:8px;color:#73849d}.problem-story-rail>button.active{background:#ffffff08;color:#d3e0f1;border-color:#ffffff2b}.problem-story-rail>button:disabled{opacity:.42;cursor:default}.problem-story-detail{min-height:170px;padding:19px;border:1px solid #ffffff10;border-radius:9px;background:#0b1017;margin-bottom:20px}.problem-story-detail pre{font:10px/1.85 var(--mono);white-space:pre-wrap;overflow-wrap:anywhere;color:#b3c9e7;margin-top:18px}.problem-story-detail h3{font-size:16px;line-height:1.7;font-weight:500;margin:14px 0;color:#c8d8ed}.problem-story-detail p{font-size:11px;line-height:1.85;color:#98acc7}.problem-story-detail code{font:10px var(--mono);color:#b4cae8;overflow-wrap:anywhere}
.problem-question{border:0;padding:0;margin:0 0 28px;min-width:0}.problem-question legend{display:flex;align-items:center;gap:11px;margin-bottom:16px;padding:0;font-size:16px;line-height:1.6;color:#d5dee9;font-weight:500}.problem-question legend>span{font:9px var(--mono);color:#7f93ae;letter-spacing:.08em}
.problem-answer{display:flex;align-items:center;gap:13px;padding:15px;margin-bottom:9px;border:1px solid #ffffff13;border-radius:10px;background:#ffffff02;cursor:pointer;position:relative;transition:background .18s,border-color .18s;color:#acbdd4;line-height:1.8;font-size:11px}.problem-answer>input{position:absolute;left:17px;top:19px;width:21px;height:21px;opacity:0}.problem-answer-letter{width:24px;height:24px;border:1px solid #ffffff1b;border-radius:6px;display:flex;justify-content:center;align-items:center;flex-shrink:0;font:9px var(--mono);color:#778eae}.problem-answer:hover{background:#ffffff06;border-color:#ffffff2a}.problem-answer:has(input:checked){background:#c1d3eb0a;border-color:#b8cce744;color:#d0dff3}.problem-answer:has(input:checked) .problem-answer-letter{background:#d6e0ee;color:#1b2737;border-color:#d6e0ee}.problem-answer:has(input:focus-visible){outline:2px solid #d4dfed;outline-offset:3px}.problem-answer>span:nth-of-type(2){flex:1;overflow-wrap:anywhere}.problem-answer-mark{width:17px;flex-shrink:0}.problem-answer-mark svg{width:15px}.problem-answer.answer-right{border-color:#cad9ed77}.problem-answer.answer-wrong{border-style:dashed;border-color:#a0acbd77;background:#ffffff04}
.problem-feedback{display:flex;gap:8px;color:#8fa6c7;font-size:10px;line-height:1.85;padding:0 5px;margin:14px 0}.problem-feedback>svg{width:15px;flex-shrink:0;margin-top:2px}.problem-feedback strong{font-weight:500;color:#c9d8ee}.problem-feedback.is-correct{color:#adbed5}.problem-finish-note{border:1px solid #ffffff15;border-radius:10px;padding:20px;margin-top:25px;font-size:12px;color:#bfd1e9}.problem-finish-note p{font-size:11px;line-height:1.8;color:#91a9ca;margin:10px 0 0}.problem-finish-note button{appearance:none;color:#c8daf2;background:transparent;border:0;border-bottom:1px solid #ffffff35;padding:2px;font:inherit;cursor:pointer}
.problem-ready{display:flex;align-items:center;gap:17px;flex-wrap:wrap;margin-top:25px;padding:22px;border:1px solid #d1deef35;border-radius:12px;background:#d2deef06}.problem-ready>span{display:grid;place-items:center;width:37px;height:37px;border:1px solid #ffffff20;border-radius:50%;color:#b7cee9}.problem-ready h3{font-size:19px;letter-spacing:-.5px;font-weight:500;color:#d4e0f0;margin:0 0 5px}.problem-ready p{font-size:10px;color:#8fa8ca;margin:0}.problem-ready .button{margin-top:6px;flex-basis:100%}
.problem-win{text-align:center;border:1px solid #d1deef30;border-radius:14px;padding:35px 25px;margin-top:25px;background:radial-gradient(ellipse at top,#c2d2e318,transparent 65%)}.problem-win-icon{display:grid;place-items:center;width:53px;height:53px;border:1px solid #ffffff2b;border-radius:50%;margin:0 auto 22px;color:#c9dbf2}.problem-win-icon svg{width:26px;height:26px}.problem-win h2{font-size:29px;font-weight:500;letter-spacing:-1px;color:#e1e9f5;margin:13px 0}.problem-win p{font-size:12px;line-height:1.9;color:#acbfd9;max-width:470px;margin:0 auto 24px}.problem-win>div{display:flex;flex-wrap:wrap;gap:10px;justify-content:center}
.problem-workspace button:focus-visible,.problem-workspace a:focus-visible{outline:2px solid #c4cbd5;outline-offset:4px}.problem-workspace [hidden]{display:none!important}
/* Cipher puzzles retain their real transforms, with a smaller first step. */
.puzzle-guide{border:1px solid #ffffff15;border-radius:14px;background:linear-gradient(120deg,#ffffff07,#ffffff02);padding:21px 23px;margin:20px 0;display:grid;grid-template-columns:1fr auto;gap:20px;align-items:center}.puzzle-guide .problem-kicker{margin-bottom:7px}.puzzle-guide h2{font-size:20px;letter-spacing:-.6px;line-height:1.4;font-weight:500;margin:0 0 7px}.puzzle-guide p{font-size:11px;line-height:1.85;color:#a8b3c3;max-width:650px;margin:0}.puzzle-guide .button{font-size:10px;white-space:nowrap}.puzzle-help-steps{display:flex;gap:12px;flex-wrap:wrap;font-size:10px;color:#8e9baa;margin-top:13px}.puzzle-help-steps>span{display:flex;align-items:center;gap:7px}.puzzle-help-steps b{font:8px var(--mono);color:#d5dde8;border:1px solid #ffffff22;width:19px;height:19px;display:grid;place-items:center;border-radius:50%}.puzzle-tool-help{border:1px solid #ffffff15;border-radius:10px;margin-bottom:15px;overflow:hidden}.puzzle-tool-help>summary{cursor:pointer;padding:13px 17px;color:#aab7c9;font-size:11px}.puzzle-tool-help>p{padding:0 17px 13px;font-size:11px;line-height:1.85;color:#8c9fb9;margin:0}.puzzle-guide-feedback{font-size:11px;color:#b9c8db;padding:0 4px;margin-bottom:17px;line-height:1.8}.puzzle-guide-feedback:empty{display:none}
/* Word reveals run once as a heading enters view. Text remains selectable. */
.cb-word{display:inline-block;max-width:100%;overflow-wrap:anywhere;transform-origin:50% 100%}.word-ready.word-visible .cb-word{animation:cb-word-in .65s cubic-bezier(.22,1,.36,1) backwards;animation-delay:var(--word-delay,0ms)}
@keyframes cb-word-in{from{opacity:.3;transform:translateY(.38em) rotate(.6deg)}to{opacity:1;transform:translateY(0) rotate(0)}}
.result-enter{animation:cb-result-in .25s ease-out both}@keyframes cb-result-in{from{opacity:.6;transform:translateY(5px)}to{opacity:1;transform:none}}
@media(min-width:1500px){.problem-layout{grid-template-columns:minmax(0,1fr) 275px}.problem-pane.panel{padding:38px}.problem-coach.panel{padding:27px}}
@media(max-width:1100px){.problem-layout{grid-template-columns:minmax(0,1fr) 210px;gap:16px}.problem-pane.panel{padding:25px}.problem-coach.panel{padding:19px}.problem-coach h2{font-size:21px}.problem-steps>button{font-size:10px;padding:11px 7px;gap:7px}.problem-step-number{width:25px;height:25px}.problem-experiment{padding:18px}.problem-experiment-label>span+span{display:none}}
@media(max-width:900px){.problem-layout{grid-template-columns:minmax(0,1fr)}.problem-sidebar{position:static;display:grid;grid-template-columns:1fr 1fr;align-items:start}.problem-coach.panel{grid-row:span 3}.problem-local-caption{padding:0 3px}.problem-header h1{font-size:34px}.problem-coach-icon{margin:19px 0 15px}.problem-coach h2 br{display:none}}
@media(max-width:600px){.problem-breadcrumb{margin-bottom:23px;gap:8px;font-size:10px}.problem-breadcrumb>span{display:none}.problem-header{margin-bottom:23px;gap:10px}.problem-header h1{font-size:29px;letter-spacing:-1px}.problem-save{font-size:0;padding:10px;min-width:37px;min-height:37px}.problem-save svg{width:15px}.problem-kicker{font-size:8px;letter-spacing:.1em}.problem-meta{gap:8px;font-size:10px}.problem-meta>span+span:not(.problem-completed-label):before{margin-right:8px}.problem-steps{gap:3px}.problem-steps>button{flex-direction:column;align-items:center;text-align:center;padding:10px 3px;gap:7px;font-size:9px;line-height:1.5}.problem-step-number{width:25px;height:25px;font-size:8px}.problem-path{margin-bottom:17px}.problem-progress{margin-top:11px}.problem-pane.panel{padding:21px 17px;border-radius:14px}.problem-pane-heading h2{font-size:26px;letter-spacing:-.8px}.problem-pane-heading>p{font-size:11px}.problem-idea{padding:18px}.problem-idea>p{font-size:15px;line-height:1.8}.problem-mini-flow{gap:6px;padding:23px 0}.problem-mini-flow>div{padding:15px 5px;min-height:129px;justify-content:center}.problem-mini-flow strong{font-size:9px}.problem-mini-flow small{font-size:8px}.problem-mini-flow>b{font-size:12px}.problem-mission h3{font-size:16px}.problem-mission>p{font-size:11px}.problem-pane-footer{gap:8px}.problem-pane-footer>span{display:none}.problem-pane-footer>.button:last-child{margin-left:auto}.problem-pane-footer .button{font-size:10px;min-height:40px;padding:10px 12px}.problem-term>span{font-size:10px}.problem-term>span+span{font-size:8px}.problem-sidebar{grid-template-columns:1fr}.problem-coach.panel{grid-row:auto;display:none}.problem-reference summary{font-size:11px}.problem-local-caption{font-size:9px}.problem-line{padding:9px 9px;gap:9px;font-size:10px}.problem-line>span{width:14px}.problem-line>i{display:none}.problem-evidence-caption{padding:13px 11px;font-size:7px;gap:5px}.problem-evidence-caption>span+span{letter-spacing:0}.problem-experiment{padding:17px 14px}.problem-experiment-label{font-size:7px;letter-spacing:.04em}.problem-experiment>h3{font-size:18px}.problem-model-result pre{font-size:9px;padding:13px}.problem-result-title>span{display:none}.problem-story-rail{gap:5px}.problem-story-rail>button{padding:10px 8px;font-size:9px}.problem-story-detail{padding:16px 13px}.problem-question legend{font-size:15px;gap:8px}.problem-answer{padding:13px 10px;gap:10px;font-size:10px}.problem-answer-letter{width:22px;height:22px}.problem-answer-mark{width:13px}.problem-question{margin-bottom:25px}.problem-ready{padding:19px 15px}.problem-win{padding:28px 17px}.problem-win h2{font-size:25px}.puzzle-guide{grid-template-columns:1fr;padding:19px;gap:17px}.puzzle-guide h2{font-size:19px}.puzzle-guide .button{justify-self:start}.puzzle-help-steps{gap:9px;font-size:9px}.problem-notes summary>span{display:none}.problem-buffer>span{height:24px}.problem-buffer{gap:3px}.problem-log-bars code{width:95px}}
@media(prefers-reduced-motion:reduce){.cb-word,.word-ready.word-visible .cb-word,.result-enter{animation:none!important;opacity:1!important;transform:none!important;filter:none!important}.problem-progress>span,.problem-switch-track,.problem-switch-track:after{transition:none!important}}
.motion-off .cb-word,.motion-off .word-ready.word-visible .cb-word,.motion-off .result-enter{animation:none!important;opacity:1!important;transform:none!important;filter:none!important}.motion-off .problem-progress>span{transition:none!important}
.problem-mobile-hint{display:none}.problem-quick-hint-text{display:none}
@media(max-width:600px){.problem-mobile-hint{display:inline-flex;align-items:center;gap:5px;margin-left:auto;appearance:none;background:#ffffff04;border:1px solid #ffffff17;border-radius:7px;padding:7px 9px;color:#bac3d0;font:10px var(--font);cursor:pointer}.problem-mobile-hint svg{width:12px}.problem-breadcrumb .problem-tutor-link{margin-left:6px}.problem-quick-hint-text:not(:empty){display:block;border:1px solid #ffffff1c;border-radius:11px;background:#ffffff04;padding:16px 18px;margin-bottom:17px;font-size:11px;color:#c3cbd7;line-height:1.85}.problem-quick-hint-text>span{font:8px var(--mono);letter-spacing:.08em;color:#8997ac}.problem-quick-hint-text>p{margin:8px 0 0}}