:root{color-scheme:dark;--bg:#101214;--paper:#171a1d;--ink:#e8ebef;--muted:#939ba4;--mint:#b8dfc9;--line:#30363b;font-family:Inter,'Segoe UI',system-ui,-apple-system,sans-serif}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--ink);font-size:14px;line-height:1.6;overflow:hidden}button,input,textarea,select{font:inherit}button{cursor:pointer}button:disabled{cursor:not-allowed;opacity:.35}button,a,input,textarea,select{outline-offset:4px}:focus-visible{outline:2px solid var(--mint)}[hidden]{display:none!important}svg{width:20px;height:20px;fill:none;stroke:currentColor;stroke-width:1.7;stroke-linecap:round;stroke-linejoin:round;flex-shrink:0}.svg-defs{position:absolute;width:0;height:0;overflow:hidden}.notebook-header{height:72px;display:flex;align-items:center;justify-content:space-between;padding:0 24px;gap:14px;background:var(--bg);border-bottom:1px solid #252b30}.brand{display:flex;gap:13px;align-items:center;text-decoration:none;color:#cbd0d6;min-width:0}.brand-icon{font-family:Georgia,serif;font-style:italic;font-weight:bold;font-size:24px;line-height:1;background:#293a33;color:#c5e7d4;width:34px;height:34px;border:1px solid #425b4c;border-radius:11px;display:grid;place-items:center}.document-title{font-size:14px;font-weight:500;white-space:nowrap}.save-status{font-size:11px;color:#737f88;white-space:nowrap}.header-actions{display:flex;align-items:center;gap:10px}.header-center{display:flex;align-items:center;gap:14px;min-width:0}.connect,.quiet{display:inline-flex;align-items:center;justify-content:center;gap:9px;background:#232a2e;color:#d4e1da;border:1px solid #465b50;border-radius:22px;min-height:38px;padding:8px 15px;font-size:12px}.connect:hover,.quiet:hover{background:#2a3930}.connect svg{width:16px;height:16px}.icon-button{width:36px;height:38px;line-height:1;border:0;background:transparent;color:#b1bac2;font-size:26px;border-radius:10px;letter-spacing:2px}.icon-button:hover{background:#23282c}.paper-stage{height:calc(100dvh - 72px);overflow:auto;overscroll-behavior:contain;padding:0 24px 150px;background:radial-gradient(ellipse at 50% 25%,#1b1f22 0,#131619 80%);scrollbar-width:thin;scrollbar-color:#3e4944 transparent}.canvas-wrap{max-width:760px;position:relative;margin:26px auto;background:var(--paper);border:1px solid #2c3337;border-radius:22px;overflow:hidden;box-shadow:0 18px 50px #00000040}#board{width:100%;height:auto;display:block;touch-action:none;cursor:crosshair;aspect-ratio:auto;border-radius:22px}#board:focus-visible{outline-offset:-5px}.canvas-wrap>input{position:absolute;z-index:5;background:#25352c;color:#e9f2ec;border:1px solid #8ab59b;border-radius:5px;padding:6px 10px;font-size:20px;width:65%;max-width:430px}.floating-tools{position:fixed;bottom:32px;left:50%;transform:translateX(-50%);z-index:20;display:flex;align-items:center;gap:13px;padding:9px 11px;border:1px solid #41494d;border-radius:19px;background:#24292df5;box-shadow:0 12px 38px #0007,inset 0 1px 0 #ffffff08;backdrop-filter:blur(18px)}.tool-group{display:flex;gap:4px}.tool{display:grid;place-items:center;width:43px;height:43px;border:1px solid transparent;border-radius:11px;background:transparent;color:#b6bfc8}.tool:hover{background:#343b40;color:#eff4f0}.tool.selected{background:#c0dfcc;color:#1c3427;border-color:#c0dfcc;box-shadow:0 2px 8px #0002}.tool svg{width:21px;height:21px}.divider{height:25px;width:1px;background:#444c52}.done{display:flex;align-items:center;justify-content:center;gap:8px;height:43px;min-width:111px;padding:0 17px;color:#d6eadd;background:#34483c;border:1px solid #5b7965;border-radius:11px;font-size:13px;font-weight:550}.done:hover{background:#3f5b48}.done svg{width:17px;height:17px}.tutor-caption{position:fixed;bottom:52px;left:32px;display:flex;gap:9px;align-items:center;font-size:11px;color:#949fa7;max-width:260px;z-index:10}.tutor-dot{width:7px;height:7px;background:#69766f;border-radius:50%;box-shadow:0 0 0 4px #889b8d0d}.connected .tutor-dot{background:#bbddc7;box-shadow:0 0 14px #a5e4be55}.tutor-caption>button{border:0;background:none;color:#a8bbb0;font-size:18px;padding:4px 7px}.board-status{position:fixed;right:28px;bottom:45px;width:230px;text-align:right;font-size:11px;line-height:1.7;color:#89949c;margin:0;pointer-events:none}.connection-notice{position:fixed;right:80px;top:53px;font-size:9px;margin:0;color:#78877e;z-index:10;pointer-events:none}.feedback{position:fixed;left:50%;bottom:116px;transform:translateX(-50%);background:#26332b;color:#d0e5d7;border:1px solid #52695b;border-radius:12px;max-width:min(600px,calc(100vw - 40px));padding:11px 17px;font-size:13px;line-height:1.6;box-shadow:0 5px 25px #0005;z-index:15}.feedback.retry,.feedback.unclear{background:#322f25;border-color:#756b4b;color:#e7ddc5}.popover{position:fixed;z-index:40;background:#20252a;border:1px solid #414b52;border-radius:15px;box-shadow:0 20px 65px #0008;padding:14px;color:var(--ink)}.menu{top:62px;right:25px;width:280px;max-height:calc(100dvh - 90px);overflow:auto;scrollbar-width:thin}.menu>button{display:block;width:100%;text-align:left;padding:9px 11px;border:0;border-radius:7px;background:none;color:#c5ced6;font-size:12px;min-height:36px}.menu>button:hover{background:#30383d}.menu label{display:flex;align-items:center;justify-content:space-between;gap:10px;font-size:11px;color:#a3aeb8;margin:0 0 12px;padding:0 5px}.menu select{min-width:0;max-width:164px;font-size:11px;border:1px solid #53616b;background:#262e33;color:#dee5e9;padding:5px;border-radius:5px}.menu input[type=range]{width:125px;accent-color:var(--mint)}.menu details{padding:10px 9px 0;font-size:11px;color:#a1adb7}.menu summary{cursor:pointer;min-height:26px}.menu textarea{width:100%;min-height:100px;background:#141a1e;color:var(--ink);border:1px solid #53616b;border-radius:6px;font-size:12px;padding:8px}.popover-head{display:flex;align-items:center;justify-content:space-between;gap:15px;margin-bottom:12px;color:#dde5eb;font-size:14px;font-weight:500}.popover-head button{background:none;border:0;color:#a9b7c0;font-size:25px;line-height:1;min-width:32px;min-height:32px;cursor:pointer}.conversation{left:28px;bottom:100px;width:330px;max-height:70dvh;display:flex;flex-direction:column;padding:18px}.privacy-note{font-size:11px;color:#97a8a0;line-height:1.8;margin:0 0 12px}.transcript{font-size:12px;line-height:1.8;max-height:340px;overflow:auto;scrollbar-width:thin;overflow-wrap:anywhere}.transcript p{margin:0 0 11px}.transcript strong{font-size:11px;color:#b9d8c6}.transcript .learner strong{color:#a3adb7}#live-form{display:flex;gap:8px;margin-top:12px}#live-message{width:100%;min-width:0;background:#151c20;color:var(--ink);border:1px solid #56646e;border-radius:8px;padding:9px;font-size:13px}#send-live{border:1px solid #536c5d;background:#35483b;color:#dce9e1;border-radius:8px;width:40px;flex-shrink:0;font-size:18px}.sheet{width:min(760px,calc(100vw - 32px));max-height:85dvh;background:#1c2226;border:1px solid #4e5d65;border-radius:17px;color:var(--ink);padding:23px;box-shadow:0 25px 80px #0008}.sheet::backdrop{background:#080b0eaa}.sheet h2{font-size:18px;font-weight:500;margin:0}.sheet textarea{width:100%;height:300px;background:#131a1e;border:1px solid #54636e;color:#d9e1e7;border-radius:8px;padding:12px;font:12px/1.8 ui-monospace,monospace}.sheet p,.muted{font-size:12px;color:#a5b1b9}.history-item{border-top:1px solid #3d484f;padding:17px 0}.history-item p{margin:3px 0}.history-item img{width:100%;max-width:500px;border:1px solid #3c4944;border-radius:9px;margin-top:9px}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}@media(max-width:1100px){.board-status{display:none}.tutor-caption{bottom:111px;left:50%;transform:translateX(-50%);max-width:90vw;white-space:nowrap}.floating-tools{bottom:25px}.feedback{bottom:155px}.conversation{bottom:150px}}
@media(max-width:900px){.save-status{display:none}}@media(max-width:600px){.notebook-header{height:62px;padding:0 12px;gap:8px}.brand{gap:9px}.brand-icon{height:30px;width:30px;border-radius:9px;font-size:22px}.document-title{font-size:12px}.header-actions{gap:6px}.connect,.quiet{font-size:11px;min-height:35px;padding:7px 10px}.connect svg{width:14px;height:14px}.save-status{display:none}.icon-button{width:28px;font-size:24px}.paper-stage{height:calc(100dvh - 62px);padding:0 0 150px}.canvas-wrap{max-width:100%;margin:12px auto;border-radius:16px}#board{border-radius:16px}#board{width:100%;min-height:0;aspect-ratio:auto}.floating-tools{bottom:max(18px,env(safe-area-inset-bottom));gap:8px;padding:7px 8px;border-radius:16px;width:max-content;max-width:calc(100vw - 20px)}.tool{width:36px;height:41px;border-radius:9px}.tool-group{gap:1px}.tool svg{width:19px;height:19px}.done{height:41px;min-width:83px;font-size:12px;padding:0 10px;gap:5px}.done svg{width:15px;height:15px}.divider{height:22px}.tutor-caption{bottom:88px;font-size:10px;max-width:calc(100vw - 30px)}.feedback{bottom:128px;font-size:12px;padding:10px 13px}.connection-notice{top:48px;right:50px;font-size:7px}.conversation{left:12px;bottom:125px;width:calc(100vw - 24px);max-height:65dvh}.menu{top:55px;right:10px;width:270px}.canvas-wrap>input{font-size:16px}.sheet{padding:18px}}@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;animation:none!important;transition:none!important}}

.connection-notice{top:auto;bottom:110px;left:50%;right:auto;transform:translateX(-50%);width:max-content;max-width:calc(100vw - 30px);text-align:center;font-size:10px;line-height:1.5}@media(max-width:600px){.connection-notice{font-size:9px;bottom:117px}}

#live-status{white-space:normal;overflow-wrap:anywhere;min-width:0}.tutor-dot,.tutor-caption>button{flex-shrink:0}

.view-switch{display:inline-flex;gap:3px;padding:3px;border:1px solid #333c41;border-radius:16px;background:#1b2024}
.view-switch a{display:inline-flex;align-items:center;min-height:30px;padding:4px 13px;border-radius:13px;font-size:12px;text-decoration:none;color:#9fabb3}
.view-switch a:hover{color:#dbe4e9}
.view-switch a[aria-current=page]{background:#2e3c34;color:#cfe6d9;box-shadow:inset 0 0 0 1px #46604f}
@media(max-width:600px){.document-title{display:none}.view-switch a{padding:4px 10px;font-size:11px}}