.study-cards{max-width:800px;margin:0 auto;padding:32px 28px;text-align:center}.study-cards__toolbar{display:flex;align-items:center;justify-content:center;gap:16px;margin-bottom:24px}.study-cards__toolbar p{margin:0}.study-cards__toolbar button{flex:0 0 44px;width:44px;height:44px;background:transparent;border:0;border-radius:50%;color:#102d43;font-size:28px;cursor:pointer}.study-cards__toolbar button:hover:not(:disabled){background:#102d430b}.study-cards__toolbar button:disabled{opacity:.25;cursor:default}.study-card-stack{position:relative;isolation:isolate;perspective:1400px;margin:0 0 40px}.study-card-stack.has-stack:after,.study-card-stack.has-stack:before{content:"";position:absolute;inset:0;border:1px solid #dce1e5;border-radius:24px;background:#f5f7f8;z-index:-1;pointer-events:none}.study-card-stack.has-stack:before{transform:translate(8px,14px) rotate(2deg)}.study-card-stack.has-stack:after{transform:translate(-5px,7px) rotate(-1deg);background:#fcfcfc}.study-card{position:relative}.study-card__inner{display:grid;transform-style:preserve-3d;transition:transform .5s cubic-bezier(.2,.7,.3,1)}.study-card__inner.is-flipped{transform:rotateY(180deg)}.study-card__face{grid-area:1/1;min-width:0;background:white;border:1px solid #dce1e5;border-radius:24px;box-shadow:0 12px 36px #112e4210;backface-visibility:hidden;-webkit-backface-visibility:hidden;display:flex;flex-direction:column}.study-card__back{transform:rotateY(180deg)}.study-card__flip{display:flex;flex:1 1;flex-direction:column;justify-content:center;gap:16px;width:100%;min-height:370px;padding:32px;border:0;border-radius:24px;background:transparent;color:#102d43;text-align:left;cursor:pointer;font:inherit}.study-card__flip strong{font-size:clamp(24px,4vw,34px);line-height:1.3}.study-card__flip small{color:#526d80;font-size:14px;margin-top:16px}.study-card__back .study-card__flip{min-height:290px;font-size:18px;line-height:1.6}.study-card__answer{display:block}.study-card__actions{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:0 24px 24px}.study-card__actions button{width:58px;height:58px;border-radius:50%;font-size:30px;font-weight:700;cursor:pointer;border:2px solid}.study-card__wrong{color:#b42318;background:#fff0ed}.study-card__right{color:#157347;background:#eaf7ef}.study-card__actions button:disabled{opacity:.4;cursor:default}.study-card--left{animation:card-left .24s ease forwards}.study-card--right{animation:card-right .24s ease forwards}.study-card__complete{background:white;border:1px solid #dce1e5;border-radius:24px;padding:40px;margin:24px 0}.study-cards button:focus-visible{outline:3px solid #245fff;outline-offset:4px}.chapter-completion-note{width:-moz-fit-content;width:fit-content;max-width:100%;margin:24px auto 0;text-align:center;justify-content:center}.study-cards .chapter-completion-note{font-size:14px}.learner-mode-switch{flex-wrap:wrap}.public-sample{max-width:850px;margin:0 auto;padding:40px 20px}.public-sample header{margin-bottom:24px}.public-sample fieldset{border:0;padding:0}.public-sample legend{font-size:clamp(24px,4vw,32px);font-weight:700;margin-bottom:24px}.public-sample__option{display:block;width:100%;text-align:left;padding:18px;margin:12px 0;border:2px solid #dce1e5;border-radius:14px;background:white;color:#102d43;cursor:pointer}.public-sample__option[aria-pressed=true]{border-color:#245fff;background:#eef3ff}.public-sample__feedback{padding:20px;border-radius:14px;background:#fff;margin:24px 0}.public-sample nav{display:flex;gap:16px;flex-wrap:wrap}.public-sample__brand{display:flex;align-items:center;gap:12px;margin-bottom:32px;font-weight:700}.public-sample__brand img{width:40px;height:40px}@keyframes card-left{to{transform:translateX(-90%) rotate(-10deg);opacity:0}}@keyframes card-right{to{transform:translateX(90%) rotate(10deg);opacity:0}}@media(prefers-reduced-motion:reduce){.study-card__inner{transition:none}.study-card--left,.study-card--right{animation:none}}@media(max-width:480px){.study-cards{padding:24px 20px}.study-cards__toolbar{gap:4px}.study-cards__toolbar p{font-size:11px}.study-card__flip{padding:22px}.study-card__actions{padding:0 16px 20px}.study-card__actions span{font-size:14px}}