@import url('https://fonts.googleapis.com/css2?family=Be+Vietnam+Pro:wght@400;450;500;550;600;650;700;750;800&display=swap');
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@media(min-width:1550px){main{padding-top:48px}.learning-grid{grid-template-columns:minmax(0,1fr) 290px}.question-body{padding:35px}.question-text{max-width:65ch}.sidebar{width:255px}.workspace{margin-left:255px}}
@media(max-width:1200px){.sidebar{width:210px;padding:30px 16px}.workspace{margin-left:210px}main{padding:30px 25px}.topbar{padding:0 25px}.learning-grid{grid-template-columns:minmax(0,1fr) 230px;gap:16px}.subject-badge{display:none}h1{font-size:24px}.session-bar{gap:12px}.session-bar label:first-child{max-width:280px}.question-body{padding:23px}.sheet-top,.sheet-bottom{padding:18px 23px}h2.question-text{font-size:21px}.answer{padding:13px}.small-primary{gap:8px}}
@media(max-width:980px){.sidebar{width:190px;padding:25px 12px}.workspace{margin-left:190px}.nav-item{font-size:11px;gap:9px;padding:12px 10px}.brand-caption{font-size:11px}.learning-grid{grid-template-columns:minmax(0,1fr)}.right-column{display:grid;grid-template-columns:1fr 1fr;gap:15px}.right-column .panel{margin-bottom:0}.right-column .tip-panel,.right-column .source-meta{display:none}.navigator{grid-template-columns:repeat(8,1fr);max-height:150px}.q-dot{min-height:25px}.local-status{display:none}.session-bar{flex-wrap:wrap}.session-bar label:first-child{max-width:none;min-width:180px}.text-button#shuffle{margin-left:auto}.small-primary{margin-left:0}.question-body{min-height:300px}.sidebar-note p{font-size:21px}}
@media(max-width:650px){.sidebar{position:sticky;top:0;width:100%;padding:13px 20px;display:block}.brand{font-size:30px;width:max-content}.brand-icon{width:29px;height:30px;border-radius:7px}.brand-icon .icon{width:20px}.brand-caption{display:none}.mobile-menu{display:block;position:absolute;right:20px;top:17px;border:0;background:none;color:#d6ec9a}.sidebar-body{display:none;padding-top:25px}.sidebar.open .sidebar-body{display:block}.sidebar-note,.source-note{display:none}.sidebar-body nav{display:grid;grid-template-columns:1fr 1fr;gap:3px}.nav-label{display:none}.nav-item{margin-bottom:3px;font-size:11px}.workspace{margin-left:0}.topbar{height:49px;padding:0 20px;font-size:11px}main{padding:26px 17px 20px}.page-heading{margin-bottom:25px}h1{font-size:23px;letter-spacing:-.8px}.page-heading p{font-size:11px;line-height:1.8}.study-tabs{margin-bottom:19px;gap:23px}.study-tabs>span{font-size:11px}.session-bar{gap:12px;margin-bottom:20px}.session-bar label:first-child{min-width:0;flex-basis:65%}.session-bar label:nth-child(2){flex:1}.session-bar .text-button{margin-right:auto;margin-left:0;padding-left:2px}.small-primary{margin-left:auto}.sheet-top{padding:16px}.topic-chip{font-size:11px}.question-body{padding:20px 17px}.question-tools{margin-bottom:17px}h2.question-text{font-size:20px;line-height:1.65;margin-bottom:22px}.answer{font-size:12px;padding:12px;gap:10px}.answer-letter{width:27px;height:29px}.answer-result{font-size:11px;white-space:normal;max-width:32px}.sheet-bottom{padding:16px 17px;flex-wrap:wrap}.sheet-bottom .primary{font-size:11px;padding:11px 14px}.sheet-bottom .secondary{font-size:11px;padding:11px 13px}.keyboard-hint{display:none}.right-column{margin-top:0;grid-template-columns:1fr;gap:14px}.right-column .panel:first-child{display:none}.navigator{grid-template-columns:repeat(8,1fr);max-height:190px}.panel{padding:18px}.page-footer{font-size:11px;line-height:1.8;align-items:start;margin-top:25px}.page-footer span:last-child{text-align:right}.learning-grid{gap:18px}.empty,.result{padding:30px 20px}.empty h2,.result h2{font-size:22px}.library-tools{flex-wrap:wrap}.library-tools select{max-width:none;width:100%}.search{flex-basis:100%}.session-bar select{font-size:11px}.skip{left:20px}.answer-type{font-size:11px}}
@media(prefers-reduced-motion:reduce){*,*:before,*:after{animation:none!important;transition:none!important;scroll-behavior:auto!important}}

.answer{font-size:14px}.page-heading p{font-size:13px}.tip-panel p{font-size:12px}.nav-item{min-height:44px}.save-button{min-height:36px}.question-text:focus{outline:none}.source-note div span{font-size:11px}@media(max-width:650px){.answer{font-size:14px}.subject-badge{display:none}.topbar{font-size:11px}.study-tabs>span{font-size:11px;max-width:45%;text-align:right;line-height:1.6}.session-bar label:first-child{flex-basis:60%}.session-bar select{font-size:11px}.q-dot{min-height:32px}.save-button{font-size:11px}.sheet-bottom>.text-button{font-size:11px}}

@media(max-width:650px){.session-bar label:first-child{flex:1;min-width:0}.session-bar label:nth-child(2){flex:0 0 95px}.session-bar label:nth-child(2) select{padding-right:24px}}

body[data-view="library"] .session-bar>:not(:first-child){display:none}body[data-view="library"] .session-bar label:first-child{max-width:400px}body[data-view="exam"] .right-column .panel:first-child{display:block}@media(max-width:650px){.session-bar label:first-child{flex:1 1 calc(100% - 107px);max-width:calc(100% - 107px)}body[data-view="library"] .session-bar label:first-child{max-width:100%}.session-bar label:nth-child(2){flex:0 0 95px}body[data-view="exam"] .right-column .panel:first-child{position:relative}.timer{font-weight:650}}
.nav-label{color:#a9c0b4}
.donate-dialog{max-width:460px;width:calc(100% - 32px);max-height:calc(100dvh - 32px);overflow:auto;padding:28px}
.donate-dialog h2{margin:0 40px 12px 0;font-size:23px;font-weight:650;letter-spacing:-.5px;line-height:1.5}
.donate-dialog p{margin:0;line-height:1.8}
.donate-close{position:absolute;right:14px;top:14px;display:grid;place-items:center;width:44px;height:44px;padding:0;border:0;border-radius:7px;background:transparent;color:var(--muted)}
.donate-close:hover{background:#f0f3ec;color:var(--ink)}
.donate-qr{margin:20px 0;text-align:center}
.donate-qr img{display:block;width:220px;max-width:100%;height:auto;aspect-ratio:1;margin:0 auto}
.donate-qr figcaption{margin-top:8px;font-size:11px;line-height:1.7;color:var(--muted)}
.donate-details{margin:0;padding-top:16px;border-top:1px solid var(--line);font-size:13px;line-height:1.7}
.donate-details>div{display:flex;justify-content:space-between;gap:16px;margin-bottom:8px}
.donate-details dt{color:var(--muted)}
.donate-details dd{margin:0;text-align:right;font-weight:550}
.donate-account{font-size:18px;font-variant-numeric:tabular-nums;user-select:all}
.donate-dialog .donate-status{min-height:24px;font-size:12px;color:var(--green);margin-top:8px}
.donate-actions{display:flex;gap:10px;margin-top:12px;flex-wrap:wrap}
.donate-actions button{flex:1;min-height:44px;white-space:nowrap}
@media(max-width:400px){.donate-dialog{padding:24px 20px}.donate-dialog h2{font-size:21px}.donate-actions{flex-direction:column}.donate-qr{margin:14px 0}.donate-qr img{width:200px}}