:root{
  --ink:#252858;--muted:#7b80aa;--purple:#6b57ec;--purple2:#8b6df6;
  --lav:#f0edff;--mint:#4bd9bb;--pink:#ff5c87;--line:#e7e6f6;
  font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;
  color:var(--ink);background:#f5f6ff;font-synthesis:none
}
*{box-sizing:border-box}body{margin:0;min-width:320px;min-height:100vh;background:
radial-gradient(circle at 6% 0%,#edf0ff 0,#f9f9ff 38%,#f4f5fb 100%);overflow-x:hidden}
button,input{font:inherit}.hidden{display:none!important}.screen{min-height:100vh}
.card{background:rgba(255,255,255,.96);border:1px solid var(--line);box-shadow:0 14px 34px rgba(69,60,150,.09);border-radius:28px}
.logo{font-weight:950;font-size:34px;letter-spacing:-1.7px;color:#3f35bc;line-height:1}.logo span{color:#2d78d8}.small-logo{font-size:28px}
.tagline{color:#6e65bd;font-size:13px;margin-top:8px;font-weight:700}.sidebar{
  position:fixed;left:0;top:0;bottom:0;width:240px;padding:28px 22px;display:flex;flex-direction:column;
  background:linear-gradient(180deg,#fff 0%,#f6f3ff 100%);border-right:1px solid #e9e8f5;z-index:20
}
.brand-block{padding:4px 8px 24px}.student-nav{display:grid;gap:8px}.nav-btn,.parent-link{
  border:0;background:transparent;color:#5f6390;padding:12px 14px;border-radius:15px;display:flex;align-items:center;gap:12px;
  cursor:pointer;font-weight:800;text-align:left
}
.nav-btn.active{background:#e8e5ff;color:#4e43c9}.nav-btn:hover,.parent-link:hover{background:#efedff;color:#4e43c9}
.side-quote{margin-top:auto;background:#fff;border:1px solid #e9e6fb;border-radius:18px;padding:16px;color:#635ab6;font-size:13px;line-height:1.5;font-style:italic}
.parent-link{margin-top:12px;background:#fff;border:1px solid #e6e4f6;justify-content:center;color:#4d48b8}
.student-main{margin-left:240px;padding:28px 34px 42px;max-width:1500px}.student-header{display:flex;align-items:center;justify-content:space-between;gap:20px;margin-bottom:22px}
.hello{font-size:30px;font-weight:950;letter-spacing:-1px}.subhello{color:var(--muted);margin-top:3px}.header-actions{display:flex;gap:12px;align-items:center}
.points,.round-btn{background:#fff;border:1px solid var(--line);border-radius:16px;padding:11px 14px;color:#4d48ad}.round-btn{width:44px;height:44px;padding:0;cursor:pointer}
.student-grid{display:grid;grid-template-columns:1.03fr 1.25fr;gap:22px}.sanda-welcome{
  min-height:590px;position:relative;overflow:hidden;padding:26px;background:
  radial-gradient(circle at 18% 18%,#fff 0,#f2efff 42%,#eaf4ff 100%)
}
.sanda-welcome:after{content:"";position:absolute;width:220px;height:120px;border-radius:50%;background:#dff4ef;bottom:-58px;left:22px;filter:blur(2px)}
.sanda-home{position:absolute;left:20px;bottom:0;width:74%;max-height:520px;object-fit:contain;object-position:left bottom;z-index:2;filter:drop-shadow(0 18px 18px rgba(70,57,136,.12))}
.home-bubble{position:absolute;right:24px;top:32px;width:245px;z-index:3}.bubble{
  background:#fff;border:1px solid #e5e1f5;box-shadow:0 10px 24px rgba(68,53,140,.09);border-radius:22px;padding:17px 18px;line-height:1.45
}
.home-bubble strong{display:block;font-size:18px;color:#3c35a6;margin-bottom:7px}.home-bubble span{font-size:14px;color:#696f97}
.handwritten{position:absolute;right:28px;bottom:34px;z-index:3;color:#4f48c7;font-size:24px;font-weight:800;transform:rotate(-4deg);font-style:italic}
.right-stack{display:grid;gap:18px}.subject-card{padding:22px;display:grid;grid-template-columns:76px 1fr auto;align-items:center;gap:16px}
.subject-badge{width:64px;height:64px;border-radius:19px;background:linear-gradient(135deg,#4bd8bd,#2eb5c7);color:#fff;display:grid;place-items:center;font-size:38px;font-weight:900;box-shadow:0 9px 18px rgba(48,184,176,.18)}
.subject-badge.small{width:50px;height:50px;font-size:29px;border-radius:14px}.subject-info .tiny{font-size:19px;font-weight:950;color:#423ab3}.subject-info h2{margin:2px 0 4px;font-size:18px}.subject-info p{margin:0;color:var(--muted);font-size:13px}
.cta{border:0;border-radius:16px;background:linear-gradient(135deg,var(--purple2),var(--purple));color:#fff;font-weight:900;padding:14px 22px;cursor:pointer;box-shadow:0 10px 20px rgba(100,78,231,.22)}
.mini-cards{display:grid;grid-template-columns:repeat(3,1fr);gap:14px}.mini{padding:20px 15px;text-align:center;min-height:170px;display:flex;flex-direction:column;align-items:center;justify-content:center}
.mini-icon{font-size:31px}.mini strong{font-size:25px;color:#4b42bf;margin:5px 0}.mini span{font-size:12px;color:#7b80a4;line-height:1.35}
.knowledge{padding:22px;display:flex;align-items:center;justify-content:space-between;background:linear-gradient(135deg,#fff,#eff4ff)}.knowledge strong{display:block;font-size:18px}.knowledge span{display:block;color:var(--muted);font-size:13px;margin-top:4px}.book-icon{font-size:34px;color:#5a50d7}
.permission-error{margin-top:18px;border:1px solid #ffc9c9;background:#fff0f2;color:#9b3f50;padding:15px 17px;border-radius:16px}

.lesson-screen{display:flex;flex-direction:column;background:
linear-gradient(180deg,#f7f8ff 0%,#f8f5ff 54%,#f7f7fd 100%);padding:14px;min-height:100vh}
.lesson-top{display:grid;grid-template-columns:190px 1fr 260px;align-items:center;gap:16px;background:#fff;border:1px solid var(--line);border-radius:22px;padding:12px 16px;box-shadow:0 9px 25px rgba(64,56,131,.06)}
.lesson-brand{font-size:24px;font-weight:950;color:#3e37b1}.lesson-topic{display:flex;align-items:center;gap:12px}.lesson-topic strong{display:block;font-size:19px}.lesson-topic span{display:block;font-size:13px;color:var(--muted);margin-top:2px}
.lesson-timer{text-align:right;color:#4742b8}.lesson-timer strong{font-size:18px}.timebar{height:8px;background:#ecebfb;border-radius:999px;margin-top:7px;overflow:hidden}.timebar i{display:block;height:100%;width:0;background:linear-gradient(90deg,#3ecbb1,#65d9a8);border-radius:999px}
.lesson-body{flex:1;min-height:0;display:grid;grid-template-columns:1.05fr 1.25fr .42fr;gap:15px;margin-top:14px}
.teacher-zone,.whiteboard,.camera-float{background:#fff;border:1px solid var(--line);border-radius:28px;box-shadow:0 14px 34px rgba(57,52,125,.08)}
.teacher-zone{position:relative;overflow:hidden;display:flex;align-items:flex-end;justify-content:center;background:
radial-gradient(circle at 50% 15%,#fff 0,#f5efff 46%,#edf6ff 100%);padding:18px}
.sanda-live{width:91%;height:100%;max-height:610px;object-fit:contain;object-position:center bottom;filter:drop-shadow(0 20px 22px rgba(66,50,136,.14));transition:transform .25s ease}
.sanda-live.listening{animation:listenNod 1.9s ease-in-out infinite}.sanda-live.speaking{animation:speakMove 1.1s ease-in-out infinite}.sanda-live.thinking{animation:thinkTilt 2.4s ease-in-out infinite}.sanda-live.happy{animation:happyBounce .7s ease-in-out 2}
@keyframes listenNod{0%,100%{transform:translateY(0) rotate(0)}50%{transform:translateY(4px) rotate(.7deg)}}@keyframes speakMove{0%,100%{transform:translateY(0)}50%{transform:translateY(-4px) rotate(-.7deg)}}@keyframes thinkTilt{0%,100%{transform:rotate(0)}50%{transform:rotate(1.7deg)}}@keyframes happyBounce{0%,100%{transform:translateY(0)}50%{transform:translateY(-11px)}}
.lesson-bubble{position:absolute;right:18px;top:18px;width:46%;z-index:3;font-size:15px;font-weight:800}.whiteboard{padding:34px;display:flex;flex-direction:column;justify-content:center;position:relative;overflow:hidden;background:#fffefb}
.whiteboard:before,.whiteboard:after{content:"";position:absolute;width:90px;height:6px;border-radius:6px;background:#8c77ee;opacity:.65;transform:rotate(-33deg)}.whiteboard:before{left:25px;top:76px}.whiteboard:after{left:45px;top:101px;width:52px;background:#68c9f0}
.board-title{text-align:center;color:#4443bb;font-size:21px;line-height:1.35;margin-bottom:32px}.comparison{display:flex;align-items:center;justify-content:center;gap:30px}.frac{display:grid;justify-items:center;font-size:34px;font-weight:900;color:#2b2d73}.frac b{width:52px;height:4px;background:#2c2f79;margin:4px 0}.sign{font-size:55px;color:#9d71e8;font-weight:900}
.fraction-pie{width:170px;height:170px;border-radius:50%;border:3px solid #4d72d2;display:grid;grid-template-columns:1fr 1fr;overflow:hidden;transform:rotate(45deg);background:#fff}.fraction-pie i{border:1px solid #7ea0e8}.fraction-pie i.filled{background:#a8cdf9}
.board-note{margin-top:32px;background:#f4f1ff;border-radius:18px;padding:16px;text-align:center;color:#555a88;font-size:14px}.camera-float{align-self:start;padding:10px;position:relative}.camera-float video{width:100%;aspect-ratio:4/3;object-fit:cover;border-radius:20px;background:#1d2030}.cam-line{font-size:12px;font-weight:900;padding:8px 3px 5px}.green-dot{display:inline-block;width:9px;height:9px;background:#26ca82;border-radius:50%}.workspace-status{font-size:11px;color:#287d5c;padding:2px 3px 5px}
.lesson-footer{margin-top:14px;background:#fff;border:1px solid var(--line);border-radius:22px;padding:10px 14px;display:flex;align-items:center;gap:8px;box-shadow:0 8px 22px rgba(59,54,126,.05)}
.voice-pill{display:flex;align-items:center;gap:10px;background:#f0edff;color:#5147c6;border-radius:16px;padding:11px 14px;min-width:255px}.mic{font-size:22px}.wave{display:flex;gap:3px;height:24px;align-items:center}.wave i{width:3px;background:#7c63ef;border-radius:4px;animation:wave 1s ease-in-out infinite}.wave i:nth-child(2){animation-delay:.12s}.wave i:nth-child(3){animation-delay:.24s}.wave i:nth-child(4){animation-delay:.36s}.wave i:nth-child(5){animation-delay:.48s}@keyframes wave{0%,100%{height:5px}50%{height:22px}}
.tool-btn{border:0;background:transparent;color:#5c608a;font-weight:800;padding:8px 12px;border-radius:13px;cursor:pointer;display:flex;flex-direction:column;align-items:center;gap:4px}.tool-btn:hover{background:#f2f0ff}.tool-btn span{font-size:11px}.finish-btn{margin-left:auto;border:0;background:linear-gradient(135deg,#ff6b95,#ff456e);color:#fff;border-radius:16px;padding:14px 22px;font-weight:900;cursor:pointer}

.parent-screen{display:flex;background:#f6f7fc}.parent-sidebar{width:230px;min-height:100vh;padding:28px 20px;background:#fff;border-right:1px solid var(--line);display:flex;flex-direction:column;gap:15px}.parent-label{color:#777ba4;font-size:13px;font-weight:800}.parent-sidebar nav{display:grid;gap:8px}.parent-sidebar .parent-link{margin-top:auto}
.parent-main{flex:1;padding:28px 32px;max-width:1450px}.parent-header{display:flex;align-items:center;justify-content:space-between;margin-bottom:20px}.parent-title{font-size:29px;font-weight:950;color:#3730aa}.parent-subtitle{font-weight:850;margin-top:2px}.parent-profile{background:#fff;border:1px solid var(--line);border-radius:18px;padding:10px 14px;display:flex;align-items:center;gap:10px}.avatar-circle,.child-avatar{width:44px;height:44px;border-radius:50%;display:grid;place-items:center;background:linear-gradient(135deg,#f0c9b0,#cab7ff);font-weight:950}.parent-profile strong,.parent-profile span{display:block}.parent-profile span{font-size:12px;color:var(--muted)}
.parent-kpis{display:grid;grid-template-columns:1fr 1fr;gap:18px}.child-card,.score-card{padding:20px;display:flex;align-items:center;gap:14px}.child-card strong{display:block;font-size:22px}.child-card span,.child-card small{display:block;color:var(--muted);margin-top:2px}.score-icon{width:62px;height:62px;border-radius:18px;background:#e7fbf6;display:grid;place-items:center;color:#20bc98;font-size:30px}.score-card span,.score-card strong,.score-card small{display:block}.score-card strong{font-size:29px;margin:4px 0;color:#2c3176}.score-card small{color:#33aa85}
.parent-content{display:grid;grid-template-columns:1.05fr .95fr;gap:18px;margin-top:18px}.progress-card,.sanda-report{padding:22px}.progress-card h3,.sanda-report h3{margin:0 0 20px}.skill{display:grid;grid-template-columns:1fr auto;gap:8px;margin:15px 0}.skill span{font-size:13px;color:#5e648c}.skill strong{font-size:13px}.skill>div{grid-column:1/-1;height:8px;background:#ececf5;border-radius:999px;overflow:hidden}.skill i{display:block;height:100%;background:linear-gradient(90deg,#30c7b0,#66d9ad);border-radius:999px}
.report-body{display:grid;grid-template-columns:115px 1fr;gap:14px;align-items:center}.report-body img{width:115px;height:150px;object-fit:contain;background:#f4efff;border-radius:18px}.report-body p{color:#63698f;line-height:1.55}.signature{text-align:right;color:#4c43bd;font-style:italic;font-weight:850}
.modal{position:fixed;inset:0;background:rgba(30,28,65,.38);display:grid;place-items:center;padding:20px;z-index:60}.modal-card{width:min(520px,100%);background:#fff;border-radius:28px;padding:30px;box-shadow:0 24px 70px rgba(35,28,85,.25);position:relative}.modal-close{position:absolute;right:14px;top:12px;width:38px;height:38px;border:0;border-radius:50%;background:#f0eff9;font-size:24px;cursor:pointer}.modal-card p{color:var(--muted);line-height:1.55}.modal-card input{position:absolute;opacity:0;pointer-events:none}.modal-upload{display:inline-block;margin-top:12px}
@media(max-width:1100px){.student-grid{grid-template-columns:1fr}.sanda-welcome{min-height:470px}.sanda-home{width:62%}.lesson-body{grid-template-columns:1fr 1fr}.camera-float{position:fixed;right:16px;top:86px;width:175px;z-index:30}.lesson-footer{flex-wrap:wrap}.voice-pill{min-width:210px}.parent-content{grid-template-columns:1fr}}
@media(max-width:760px){.sidebar{position:static;width:auto;height:auto;flex-direction:row;align-items:center;padding:14px}.student-nav,.side-quote{display:none}.student-main{margin-left:0;padding:16px}.student-grid{display:block}.sanda-welcome{min-height:470px;margin-bottom:16px}.sanda-home{width:76%}.home-bubble{width:210px;right:12px}.subject-card{grid-template-columns:60px 1fr}.subject-card .cta{grid-column:1/-1}.mini-cards{grid-template-columns:1fr 1fr 1fr}.lesson-top{grid-template-columns:1fr auto}.lesson-brand{display:none}.lesson-topic{min-width:0}.lesson-timer{font-size:12px}.lesson-body{grid-template-columns:1fr}.whiteboard{min-height:380px}.teacher-zone{min-height:520px}.camera-float{width:135px;top:82px}.lesson-footer{justify-content:center}.voice-pill{width:100%}.finish-btn{margin-left:0}.parent-screen{display:block}.parent-sidebar{width:auto;min-height:auto;padding:14px;flex-direction:row;align-items:center}.parent-sidebar nav,.parent-label{display:none}.parent-main{padding:16px}.parent-kpis{grid-template-columns:1fr}.parent-content{grid-template-columns:1fr}}