.features-stack-section{background:#edf1e6;padding:6rem 0 10rem}.stack-intro{text-align:center;margin-bottom:4rem}.stack-intro>p:last-child{max-width:560px;margin:auto;color:#607153}.features-stack{position:relative}.feature-stack-card{position:sticky;top:calc(48px + var(--stack-index)*10px);z-index:calc(10 + var(--stack-index));min-height:500px;margin-bottom:90px;padding:2rem 2.4rem 2.6rem;border-radius:28px;box-shadow:0 24px 55px #24402220;border:1px solid #ffffff80;overflow:hidden}.feature-stack-card:last-child{margin-bottom:0}.stack-number{display:block;padding-bottom:1.2rem;border-bottom:1px solid #29412926;font-size:.67rem;letter-spacing:.13em;text-transform:uppercase}.stack-grid{display:grid;grid-template-columns:1fr 1fr;gap:4rem;align-items:center;min-height:390px}.stack-grid h3{font-size:clamp(2.2rem,4.2vw,4rem);letter-spacing:-.06em;margin-bottom:1.5rem}.stack-grid h3 em{font-family:Georgia,serif;font-weight:400}.stack-grid>div:first-child>p{max-width:510px;color:#455747;line-height:1.8}.stack-visual{justify-self:center;width:min(100%,430px)}.stack-chat{background:#dce9d4}.stack-syllabus{background:#e6edd0}.stack-audio{background:#f4e7cf}.stack-tests{background:#dcecf8}.stack-flash{background:#f7dfc6}.stack-summary{background:#e9e0f3}.stack-plan{background:#dce9e2}.stack-stat{display:grid;place-items:center;text-align:center;background:#f9fbf2b5;padding:2.4rem;border-radius:22px}.stack-stat strong{font:400 clamp(4rem,9vw,7rem)/1 Georgia,serif;color:#617d3f}.stack-stat span{margin-top:1rem;line-height:1.6}.stack-stat i{font-style:normal;font-size:.7rem;margin-top:1.4rem;padding:8px 12px;border-radius:100px;background:#d6e4b8}.audio-player{display:flex;align-items:center;gap:1.5rem;padding:2.2rem;background:#fffaf1;border-radius:22px;box-shadow:0 16px 35px #6b4d2220}.audio-icon{display:grid;place-items:center;flex:0 0 65px;height:65px;border-radius:50%;background:#284830;color:#fff}.audio-player>div{flex:1}.audio-player span,.audio-player small{display:block;font-size:.7rem;color:#806f58}.audio-player strong{display:block;margin:.4rem 0 1.2rem}.audio-line{height:5px;background:#e6d8c3;border-radius:5px}.audio-line i{display:block;width:64%;height:100%;background:#9a7445;border-radius:5px}.audio-player small{margin-top:.7rem}.test-sheet{padding:2rem;background:#f8fbfd;border-radius:22px}.test-sheet>span,.test-sheet>small{font-size:.7rem;color:#55758e}.test-sheet strong{display:block;margin:1rem 0 1.5rem}.test-sheet i{display:block;height:39px;margin:.7rem 0;border-radius:10px;background:#e9f0f4}.test-sheet i.selected{background:#bbd9ef;border:1px solid #6ea1c4}.test-sheet small{display:block;margin-top:1.2rem}.flash-card{position:relative;min-height:290px;padding:2.2rem;background:#fff9f1;border-radius:22px;box-shadow:13px 13px 0 #dfb887;display:flex;flex-direction:column;justify-content:center;text-align:center}.flash-card>span{position:absolute;top:18px;left:20px;font-size:.67rem;text-transform:uppercase;letter-spacing:.1em}.flash-card strong{font:400 2rem/1.25 Georgia,serif}.flash-card i{position:absolute;right:22px;top:15px;font-style:normal;font-size:1.5rem}.flash-card small{position:absolute;bottom:18px;left:0;right:0}.summary-map{display:grid;grid-template-columns:repeat(3,1fr);gap:12px;align-items:center;position:relative}.summary-map strong{grid-column:1/-1;justify-self:center;padding:1.2rem;background:#fff;border-radius:14px}.summary-map span{padding:1rem .5rem;text-align:center;background:#ffffffa8;border-radius:12px;font-size:.76rem}.calendar{display:grid;grid-template-columns:repeat(5,1fr);gap:10px;padding:2rem;background:#f7fbf8;border-radius:22px;text-align:center}.calendar>span{font-size:.7rem;color:#668070}.calendar>i{height:90px;border-radius:10px;background:#edf2ed}.calendar>i.study{background:linear-gradient(to top,#58a87b 68%,#edf2ed 68%)}.calendar small{grid-column:1/-1;margin-top:1rem;color:#668070}.chat-scene{background:#edf2e8;padding:30px;border-radius:24px;position:relative}.chat-heading{display:flex;align-items:center;gap:12px;margin-bottom:25px;font-size:1rem;font-weight:600}.chat-heading small{display:block;font-size:.7rem;color:#738369;font-weight:400}.chat-avatar{display:grid;place-items:center;width:42px;height:42px;background:#d2e1bf;border-radius:50%;font-size:27px}.chat-bubble{background:#fff;font-size:.87rem;padding:16px 19px;max-width:87%;border-radius:17px 17px 17px 3px;margin-bottom:15px;box-shadow:0 3px 8px #243e2b05}.chat-reply{margin-left:auto;border-radius:17px 17px 3px 17px;background:#d4e3bf}.chat-disclaimer{font-size:.61rem;color:#66775d;text-align:center;margin:24px 0 0}@media(max-width:1000px){.feature-stack-card{min-height:470px}.stack-grid{gap:2.5rem}}@media(max-width:760px){.features-stack-section{padding:4rem 0 7rem}.stack-intro{text-align:left;margin-bottom:2.5rem}.feature-stack-card{top:calc(10px + var(--stack-index)*7px);min-height:560px;margin-bottom:65px;padding:1.35rem 1.25rem 1.6rem;border-radius:21px}.stack-grid{grid-template-columns:1fr;gap:1.3rem;min-height:480px}.stack-grid h3{font-size:2.45rem;margin-bottom:.8rem}.stack-grid>div:first-child>p{font-size:.88rem;line-height:1.65}.stack-visual{max-width:360px}.stack-stat{padding:1.5rem}.stack-stat strong{font-size:4.6rem}.audio-player{padding:1.3rem}.calendar{padding:1.2rem;gap:6px}.calendar>i{height:65px}.summary-map{gap:7px}.summary-map span{font-size:.68rem}}@media(max-width:380px){.feature-stack-card{min-height:575px}.stack-grid h3{font-size:2.15rem}.audio-icon{flex-basis:50px;height:50px}}