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/* Spacious editorial storefront layout, with the user's shoe palette. */
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/* Exercise studio: calm surfaces, deliberate feedback, motion with meaning. */
.bank-work{border:1px solid #d5d4cc;box-shadow:0 12px 35px #18181808;position:relative;border-top:5px solid #f36a5d}.bank-prompt{background:#f4f5ef;border-left:4px solid #69c6d8;padding:24px;font-size:19px;line-height:1.8;border-radius:0 12px 12px 0}.bank-work .answer-field{margin-top:30px}.answer-field label{font-weight:700}.input-wrap{border-radius:10px;overflow:visible;background:#fff;transition:box-shadow .2s}.input-wrap input{border-radius:10px 0 0 10px;transition:background .2s,box-shadow .2s}.input-wrap input.answer-error{background:#fff1f0;box-shadow:inset 0 0 0 2px #b52c1e}.input-wrap input.answer-correct{background:#e4f6f6;box-shadow:inset 0 0 0 2px #15717b}.bank-work .actions{margin-top:18px}.bank-work .btn,.understanding-card .btn{border-radius:8px;transition:transform .18s,box-shadow .18s,background .18s}.bank-work .btn:hover:not(:disabled),.understanding-card .btn:hover:not(:disabled){transform:translateY(-2px);box-shadow:0 4px 0 #18181820}.bank-work .btn:active:not(:disabled){transform:translateY(1px)}
#bank-feedback .feedback,#feedback .feedback,.understanding-card .feedback{display:flex;align-items:flex-start;gap:14px;border-radius:12px;padding:20px;animation:feedback-in .3s ease-out}.feedback p{margin:7px 0;line-height:1.65}.feedback.error{background:#fff1f0;color:#702720;border:1px solid #e9aea8}.feedback.success{background:#e4f6f6;color:#155c64;border:1px solid #84c9cf}.feedback-icon{display:grid;place-items:center;flex:0 0 32px;height:32px;border:1px solid currentColor;border-radius:50%;font-size:19px;font-weight:700}.success .feedback-icon{animation:success-pop .5s ease-out}.attempt-note{font-size:11px;color:#702720}.hint-stack{margin:22px 0;border:1px solid #aad8df;background:#f1fbfc;border-radius:12px;overflow:hidden}.hint-step{display:flex;gap:17px;padding:20px;animation:feedback-in .3s ease-out}.hint-step+.hint-step{border-top:1px solid #c8e5e9}.hint-number{color:#225b65;font-weight:700;font-size:13px;padding-top:3px}.hint-step b{font-size:14px}.hint-step p{font-size:14px;line-height:1.8;margin:7px 0 0}.hint-stack.hidden{display:none}.bank-work #bank-solution-box{border-radius:12px;line-height:1.9;background:#fff5ea;animation:feedback-in .3s ease-out}.bank-item{transition:background .2s,transform .2s}.bank-item:hover{transform:translateX(3px)}.concept-option{transition:background .2s,border-color .2s,box-shadow .2s}.concept-option.wrong{animation:answer-shake .42s ease-out}.concept-option.right .option-letter{animation:success-pop .45s ease-out}.bank-work,.understanding-card,.exercise-work{animation:feedback-in .3s ease-out}.inline-experiment{border-radius:12px}.inline-experiment button{transition:background .2s,transform .2s}
@keyframes answer-shake{0%,100%{transform:translateX(0)}20%{transform:translateX(-7px)}40%{transform:translateX(6px)}60%{transform:translateX(-4px)}80%{transform:translateX(2px)}}
@keyframes feedback-in{from{opacity:0;transform:translateY(7px)}to{opacity:1;transform:translateY(0)}}
@keyframes success-pop{0%{transform:scale(.7)}60%{transform:scale(1.13)}100%{transform:scale(1)}}
@media(max-width:760px){.bank-prompt{padding:18px;font-size:17px}.hint-step{padding:16px}.bank-work .actions .btn{min-height:44px}.input-wrap input{font-size:18px;min-width:0}}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{animation:none!important;transition:none!important}.bank-item:hover,.bank-work .btn:hover:not(:disabled),.understanding-card .btn:hover:not(:disabled){transform:none}}
.organic-book-cover{min-height:270px;background:#f6bab4;color:#181818;display:flex;flex-direction:column;padding:25px;gap:15px;border:1px solid #181818}.organic-book-cover b{font-size:25px;line-height:1.1;letter-spacing:-1px}.organic-book-cover strong{font-size:66px;line-height:1;color:#166578}.organic-book-cover span,.organic-book-cover small{font-size:10px;letter-spacing:.08em}.openstax-credit{flex-basis:100%;font-size:10px;line-height:1.7;max-width:900px;color:#555}.openstax-credit a{color:inherit;text-decoration:underline}.bank-toolbar .segmented{flex-wrap:wrap}

/* The longer Glasshouse wordmark shares the original navigation spacing. */
.sidebar .brand{font-size:clamp(24px,2.5vw,29px);letter-spacing:-.055em}