/* StudyNest Real Numbers gold-standard additions */
.scale-hero-visual{position:relative;width:290px;height:210px;margin:auto;border-radius:28px;background:linear-gradient(145deg,#f7fbff,#fff7d8);border:2px solid rgba(23,50,77,.12);overflow:hidden}
.scale-map{position:absolute;inset:24px;border:2px dashed rgba(23,50,77,.28);border-radius:22px;background:linear-gradient(35deg,transparent 48%,rgba(245,191,66,.35) 49%,rgba(245,191,66,.35) 53%,transparent 54%)}
.scale-map:before,.scale-map:after{content:'';position:absolute;width:20px;height:20px;border-radius:50%;background:#17324d;border:5px solid #f5bf42}.scale-map:before{left:25px;bottom:32px}.scale-map:after{right:28px;top:30px}
.scale-ruler{position:absolute;left:44px;right:44px;bottom:24px;height:34px;border-radius:8px;background:#fff;border:2px solid #17324d;display:flex;align-items:end;justify-content:space-around;padding:0 8px}.scale-ruler i{width:2px;height:13px;background:#17324d}.scale-ruler i:nth-child(odd){height:21px}
.scale-unit-tag{position:absolute;right:18px;top:15px;background:#17324d;color:#fff;border-radius:999px;padding:8px 12px;font-weight:800}
.sn-interactive{border:2px solid rgba(23,50,77,.14);border-radius:22px;padding:1.3rem;background:linear-gradient(145deg,#f8fcff,#fffaf0);margin:1.4rem 0}.sn-interactive h3{margin-top:0}.sn-control-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(170px,1fr));gap:1rem;margin:1rem 0}.sn-control label{display:block;font-weight:800;margin-bottom:.4rem}.sn-control input,.sn-control select{width:100%;padding:.8rem;border:2px solid rgba(23,50,77,.22);border-radius:12px;font:inherit;background:#fff}.sn-live-answer{padding:1rem;border-radius:16px;background:#17324d;color:#fff;font-size:1.15rem;font-weight:800;text-align:center}.sn-scale-line{height:10px;border-radius:999px;background:#17324d;position:relative;margin:2rem auto 1rem;width:min(560px,90%)}.sn-scale-line:before,.sn-scale-line:after{content:'';position:absolute;top:-11px;width:3px;height:32px;background:#17324d}.sn-scale-line:before{left:0}.sn-scale-line:after{right:0}.sn-scale-marker{position:absolute;top:-14px;width:36px;height:36px;border-radius:50%;background:#f5bf42;border:3px solid #17324d;transform:translateX(-50%);transition:left .25s ease}.sn-comparison{display:grid;grid-template-columns:repeat(auto-fit,minmax(210px,1fr));gap:1rem}.sn-comparison article{padding:1rem;border-radius:18px;background:#fff;border:2px solid rgba(23,50,77,.12)}
.lesson-section.exam-focus{border-left:7px solid #f5bf42;background:#fffaf0}.lesson-section.common-mistakes{border-left:7px solid #d95c5c;background:#fff8f8}.lesson-section.summary-card{border-left:7px solid #3f8f6b;background:#f6fffb}
.level-heading{display:inline-block;margin:1rem 0 .35rem;padding:.35rem .75rem;border-radius:999px;background:#17324d;color:#fff;font-weight:800}.answer-toggle details{margin-top:1rem}.answer-toggle summary{cursor:pointer;font-weight:800}.unit-flow{display:flex;align-items:center;justify-content:center;gap:.6rem;flex-wrap:wrap;margin:1rem 0}.unit-flow span{padding:.75rem 1rem;border-radius:14px;background:#fff;border:2px solid rgba(23,50,77,.16);font-weight:800}.unit-flow b{font-size:1.4rem}
@media(max-width:640px){.scale-hero-visual{width:250px;height:190px}.sn-control-grid{grid-template-columns:1fr}}