:root{font-family:ui-rounded,"Avenir Next",system-ui,sans-serif;color:#30263F;background:#F7F4FC;--accent:#7352A3;--light:#EDE5F8;--muted:#70627C}*{box-sizing:border-box}body{margin:0}button,input{font:inherit}button,summary{cursor:pointer}button{border:0;border-radius:9px;font-weight:650;transition:background .15s,transform .15s}button:hover{transform:translateY(-1px)}button:focus-visible,summary:focus-visible,a:focus-visible{outline:3px solid #d3a63a;outline-offset:4px}.topbar{max-width:1120px;margin:auto;padding:28px 32px;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid #DDD2EC}.brand{font-size:25px;font-weight:800;letter-spacing:-1px;color:inherit;text-decoration:none;display:flex;align-items:center;gap:9px}.brand-icon{display:inline-grid;place-items:center;width:35px;height:35px;background:var(--accent);color:white;border-radius:11px;font-size:28px}.brand-dot{color:var(--accent);margin-left:-8px}.year{font-size:12px;background:#EDE5F8;border-radius:20px;padding:8px 13px}main{max-width:1060px;margin:auto;padding:42px 32px 0}.intro{margin-bottom:30px}.eyebrow{font-size:10px;letter-spacing:1.6px;font-weight:750;color:var(--muted)}h1{font-size:clamp(32px,4vw,46px);line-height:1.12;letter-spacing:-1.7px;margin:13px 0 15px}h1 span{color:var(--accent)}.intro p{font-size:15px;color:#70627C;line-height:1.7;margin:0}.workspace{background:white;border:1px solid #DDD2EC;border-radius:19px;box-shadow:0 8px 24px #30263F05;overflow:hidden}.exercise-bar{padding:23px 28px;border-bottom:1px solid #DDD2EC;display:flex;justify-content:space-between;align-items:center;gap:15px}h2{font-size:28px;letter-spacing:1px;margin:5px 0 0}.secondary{background:#EDE5F8;color:var(--accent);padding:11px 15px;font-size:12px}.secondary span{margin-left:12px;font-size:17px}.exercise-body{display:grid;grid-template-columns:1.2fr 1fr;padding:25px;gap:28px;align-items:start}.paper{background-color:#fff;background-image:linear-gradient(#7352A318 1px,transparent 1px),linear-gradient(90deg,#7352A318 1px,transparent 1px);background-size:24px 24px;border:1px solid #DDD2EC;border-radius:12px;padding:20px 14px 15px;min-width:0}.paper-header{display:flex;justify-content:space-between;font-size:10px;color:#70627C;margin:0 6px 22px}.division{display:grid;justify-content:center;--cell:38px;grid-template-columns:repeat(var(--columns),var(--cell));grid-auto-rows:48px;position:relative;font-family:ui-monospace,SFMono-Regular,Consolas,monospace;font-size:27px;font-weight:550;min-height:230px}.digit{display:grid;place-items:center;position:relative;min-width:0}.digit.source-active{color:var(--accent);background:#EDE5F8;border-radius:7px}.digit.quotient{color:var(--accent)}.t-vertical{border-left:2px solid #30263F;grid-row:1 / span var(--rows);height:100%;width:0;pointer-events:none}.t-horizontal{border-top:2px solid #30263F;grid-row:2;height:0;width:100%;pointer-events:none}.subtract-line{border-bottom:1.5px solid #70627C}.minus{color:#70627C;font-size:22px}.down{font-size:19px;color:#d49e2e}.answer{width:calc(100% - 6px);height:39px;border:2px solid #7352A3;background:#EDE5F8;border-radius:7px;color:var(--accent);text-align:center;min-width:0;padding:0;font-size:24px;font-family:inherit;outline:none;box-shadow:0 0 0 3px #7352A330}.answer:focus{box-shadow:0 0 0 4px #7352A33d}.answer.invalid{border-color:#c4654c;background:#fff1e9}.paper-footer{font-size:9px;color:#70627C;margin-top:22px;display:flex;gap:7px;align-items:center}.active-legend{width:7px;height:7px;border-radius:2px;background:#7352A3}.coach{padding:4px 0;min-width:0}.coach-top{display:flex;align-items:center;gap:9px;font-size:12px;font-weight:650}.coach-icon{display:grid;place-items:center;background:#f7edd1;color:#b28a24;border-radius:9px;width:30px;height:30px;font-size:23px}.stages{display:flex;gap:5px;margin:23px 0 21px;flex-wrap:wrap}.stages span{background:#EDE5F8;border-radius:5px;padding:7px 10px;color:#70627C;font-size:10px}.stages .current{background:#EDE5F8;color:var(--accent);font-weight:750}h3{font-size:22px;line-height:1.35;letter-spacing:-.5px;margin:0 0 12px}.coach>p{font-size:13px;line-height:1.75;color:#70627C;margin:0}#feedback{font-size:12px;min-height:38px;padding-top:12px;color:#a6503b}.coach-actions{display:flex;flex-wrap:wrap;align-items:center;gap:10px;margin-top:13px}.primary{background:var(--accent);color:white;padding:13px 17px;font-size:12px}.primary:hover{background:#5E408A}.primary span{padding-left:14px}.text-button{padding:10px 3px;background:transparent;font-size:11px;color:#70627C;text-decoration:underline;text-underline-offset:4px}.coach .hint{background:#fff6de;border-radius:8px;margin-top:14px;padding:12px;font-size:12px;color:#857038}.progress-track{height:4px;background:#EDE5F8}#progress{height:100%;background:#7352A3;transition:width .3s}.custom{border:1px solid #DDD2EC;border-radius:12px;margin-top:16px;background:#EDE5F8}.custom summary{padding:16px 21px;font-size:12px;font-weight:650;list-style:none;display:flex;justify-content:space-between}.custom summary::-webkit-details-marker{display:none}.custom form{padding:0 21px 18px;display:flex;gap:15px;align-items:end;flex-wrap:wrap}.custom label{font-size:11px;display:flex;flex-direction:column;gap:5px}.custom input{border:1px solid #DDD2EC;background:white;border-radius:7px;width:110px;padding:9px;color:inherit}.custom form>span{padding-bottom:9px}#custom-error{width:100%;margin:0;color:#a6503b;font-size:12px}.method{margin-top:31px}.method-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:18px;margin-top:18px}.method-grid>div{position:relative;padding-left:35px}.method-grid b{position:absolute;left:0;top:1px;font-size:12px;color:#70627C;background:#EDE5F8;border-radius:50%;width:26px;height:26px;display:grid;place-items:center}.method-grid h3{font-size:12px;letter-spacing:0;margin:4px 0 5px}.method-grid p{font-size:10px;line-height:1.6;color:#70627C;margin:0}footer{max-width:1060px;margin:30px auto 0;padding:20px 32px 27px;border-top:1px solid #DDD2EC;font-size:10px;color:#70627C;display:flex;justify-content:space-between;gap:15px}.success-icon{font-size:24px;border-radius:50%;background:#EDE5F8;color:var(--accent);width:48px;height:48px;display:grid;place-items:center;margin:10px 0}#result{font-size:15px;line-height:1.65;color:var(--accent)}[hidden]{display:none!important}@media(max-width:700px){.topbar{padding:20px}.brand{font-size:22px}main{padding:28px 16px 0}.intro{margin-bottom:25px}.exercise-body{grid-template-columns:1fr;padding:18px;gap:23px}.exercise-bar{padding:18px}.paper{padding:16px 10px}.coach{padding:0 3px}.stages{margin:15px 0}.method-grid{grid-template-columns:repeat(2,1fr);gap:20px}.division{--cell:34px;grid-auto-rows:43px;font-size:24px}.answer{height:35px;font-size:22px}.paper-header{margin-bottom:14px}footer{padding:18px;flex-direction:column;gap:8px}.custom form{gap:10px}.custom input{width:90px}}
.division{width:min(100%,calc(var(--columns) * var(--cell)));margin-inline:auto;grid-template-columns:repeat(var(--columns),minmax(0,1fr))}
.ad-banner{margin-top:24px;border-top:1px solid #DDD2EC;border-bottom:1px solid #DDD2EC;padding:12px 0 15px;min-width:0}.ad-label{display:block;text-align:center;font-size:9px;letter-spacing:1.4px;text-transform:uppercase;color:#70627C;margin-bottom:9px}.ad-banner .adsbygoogle{display:block;min-height:90px;width:100%}
.topbar{padding-block:14px}main{padding-top:16px}.intro{margin-bottom:16px}.intro h1{font-size:clamp(24px,3vw,32px);line-height:1.15;letter-spacing:-.6px;margin:0 0 6px}.intro p{font-size:13px;line-height:1.5;color:#70627C;margin:0}.exercise-bar{padding-block:14px}.exercise-bar h2{font-size:28px;line-height:1.2;letter-spacing:1px;margin:0}.exercise-body{padding:20px;gap:24px}.paper{padding-top:16px}.paper-header{margin-bottom:14px}.paper-footer{margin-top:14px}.division{grid-auto-rows:44px;min-height:180px}.stages{margin:0 0 16px}.coach .hint{line-height:1.6}.coach .hint p{margin:0 0 10px}.hint h4{font-size:12px;margin:0 0 7px}.table-preference{display:flex;align-items:center;gap:7px;margin:0 0 8px;color:#70627C;font-size:11px}.table-preference input{accent-color:var(--accent)}.times-table{list-style:none;padding:0;margin:0;display:flex;flex-direction:column;gap:1px;font-variant-numeric:tabular-nums}.times-table li{padding:2px 7px;border-radius:5px;white-space:nowrap}.coach-actions{gap:8px}.coach-actions .text-button{padding-inline:4px}@media(max-width:700px){.topbar{padding:12px 16px}main{padding-top:12px}.intro{margin-bottom:12px}.intro h1{font-size:25px}.exercise-body{padding:16px;gap:18px}.exercise-bar{padding:12px 16px}.exercise-bar h2{font-size:25px}.division{grid-auto-rows:43px}.stages{margin:0 0 12px}.coach-actions{gap:4px}}

.settings-options{padding:0 21px 18px;display:grid;gap:12px}.settings-options label{display:flex;flex-direction:row;align-items:center;gap:9px;font-size:12px}.settings-options input{width:auto;accent-color:var(--accent)}.settings-options p{margin:0;color:#70627C;font-size:11px}
.setting-row{display:flex;align-items:center;justify-content:space-between;gap:12px}.setting-row label{font-size:12px}.setting-row select{font:inherit;font-size:12px;padding:7px 9px;border:1px solid #DDD2EC;border-radius:7px;background:white;color:inherit}.settings-options .setting-check{justify-content:flex-start}
.decimal-comma{position:absolute;right:-4px;top:2px;pointer-events:none}
.decimal-comma-prompt{color:#a86b00;background:#fff0bf;border-radius:3px;font-weight:800;font-size:1.1em}.decimal-comma-written{color:var(--accent);font-weight:800}.decimal-guide{display:flex;align-items:center;gap:10px;margin-top:12px;padding:11px 13px;border:1px solid #e8c76e;border-radius:9px;background:#fff7df;color:#705516;font-size:12px;line-height:1.5}.decimal-guide strong{white-space:nowrap}.decimal-guide span{color:#806b32}
.settings{overflow:hidden;transition:border-color .2s,box-shadow .2s}.settings[open]{border-color:#DDD2EC;box-shadow:0 8px 24px #30263F08}.settings summary{min-height:70px;gap:12px}.settings-summary{display:flex;align-items:center;gap:13px;text-align:left}.settings-icon{display:grid;place-items:center;width:38px;height:38px;border-radius:12px;background:#EDE5F8;color:var(--accent);font-size:19px}.settings-summary strong,.settings-summary small{display:block}.settings-summary strong{font-size:13px;color:#30263F}.settings-summary small{margin-top:4px;color:#70627C;font-size:10px;font-weight:450}.settings-chevron{color:#70627C;font-size:19px;transition:transform .2s}.settings[open] .settings-chevron{transform:rotate(180deg)}.settings-options{padding:2px 21px 20px;gap:16px}.settings-heading .eyebrow{font-size:9px}.settings-heading p{margin:4px 0 0;font-size:12px;color:#70627C}.setting-grid{display:grid;grid-template-columns:1fr 1fr;gap:12px}.setting-card{display:grid!important;grid-template-columns:34px 1fr auto;gap:10px!important;min-height:74px;padding:12px;border:1px solid #DDD2EC;border-radius:11px;background:#F7F4FC;transition:border-color .15s,background .15s;cursor:pointer}.setting-card:focus-within,.setting-card:hover{border-color:#B8A0D4;background:#F7F4FC}.setting-card-icon{display:grid;place-items:center;width:32px;height:32px;border-radius:9px;background:#EDE5F8;color:var(--accent);font-size:11px;font-weight:800}.divisor-icon{font-size:21px}.setting-card-copy{display:flex;flex-direction:column;align-items:flex-start;justify-content:center;gap:4px}.setting-card-copy strong{font-size:11px}.setting-card-copy small{font-size:10px;color:#70627C}.setting-card select{min-width:83px;padding:8px 8px;border:1px solid #DDD2EC;border-radius:8px;background:white;color:#30263F;font-size:11px;font-weight:650}.setting-toggles{display:grid;gap:9px}.setting-toggle{position:relative;display:flex!important;justify-content:space-between;gap:15px!important;padding:12px 13px;border:1px solid #DDD2EC;border-radius:10px;background:#fff;cursor:pointer}.toggle-copy{display:grid;gap:4px}.toggle-copy strong{font-size:11px}.toggle-copy small{font-size:10px;color:#70627C}.setting-toggle>input{position:absolute;width:1px;height:1px;opacity:0}.switch{position:relative;flex:0 0 38px;width:38px;height:22px;border-radius:20px;background:#B8A0D4;transition:background .18s;align-self:center}.switch:after{content:"";position:absolute;top:3px;left:3px;width:16px;height:16px;border-radius:50%;background:white;box-shadow:0 1px 3px #0002;transition:transform .18s}.setting-toggle input:checked+.switch{background:var(--accent)}.setting-toggle input:checked+.switch:after{transform:translateX(16px)}.setting-toggle input:focus-visible+.switch{outline:3px solid #d3a63a;outline-offset:3px}.settings-note{display:flex;gap:8px;align-items:flex-start;padding:10px 12px;border-radius:9px;background:#EDE5F8;color:var(--accent)}.settings-note>span{font-size:14px}.settings-note p{margin:0;color:#70627C;font-size:10px;line-height:1.55}.settings-apply{display:flex;justify-content:center;align-items:center;gap:14px;width:100%;min-height:44px}.settings-apply span{font-size:16px}.settings-apply:hover{background:#5E408A}@media(max-width:700px){.settings summary{padding:13px 15px}.settings-options{padding:2px 15px 16px}.setting-grid{grid-template-columns:1fr}.setting-card{min-height:68px}}

.workspace>.settings{margin:0;border:0;border-bottom:1px solid #DDD2EC;border-radius:0;background:#F7F4FC;box-shadow:none}.workspace>.settings>summary{min-height:48px;padding:10px 28px;align-items:center}.workspace>.settings>summary:focus-visible{outline-offset:-4px}.workspace>.settings .settings-summary{min-width:0;gap:9px}.workspace>.settings .settings-icon{flex:0 0 28px;width:28px;height:28px;border-radius:8px;font-size:16px}.workspace>.settings .settings-summary>span:last-child{display:flex;align-items:baseline;flex-wrap:wrap;column-gap:12px;row-gap:4px;min-width:0}.workspace>.settings .settings-summary strong{font-size:12px}.workspace>.settings .settings-summary small{margin:0;font-size:11px;line-height:1.5}.workspace>.settings .settings-chevron{flex-shrink:0}.workspace>.settings .settings-options{padding:8px 28px 20px}@media(max-width:700px){.workspace>.settings>summary{padding:10px 16px}.workspace>.settings .settings-summary>span:last-child{display:block}.workspace>.settings .settings-summary small{margin-top:3px;font-size:10px}.workspace>.settings .settings-options{padding:4px 16px 16px}}

.setting-toggles,.setting-toggle{width:100%;min-width:0}

.workspace>.settings .settings-options{gap:12px;padding-top:6px;padding-bottom:16px}
.settings-controls{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:10px}
.settings-controls .setting-card,.settings-controls .setting-toggle{min-width:0;min-height:94px;margin:0;padding:10px;border-radius:10px;background:#fff;box-shadow:0 2px 5px #30263F03;transition:border-color .15s,background .15s}
.settings-controls .setting-card{grid-template-columns:24px minmax(0,1fr);gap:8px!important;align-content:start}
.settings-controls .setting-card-icon{width:24px;height:24px;border-radius:7px;font-size:9px}
.settings-controls .divisor-icon{font-size:18px}
.settings-controls .setting-card-copy strong,.settings-controls .toggle-copy strong{font-size:12px;line-height:1.35}
.settings-controls .setting-card select{grid-column:1/-1;min-width:0;width:100%;min-height:44px;padding:8px 10px;background:#F7F4FC;font:inherit;font-size:12px;font-weight:650}
.settings-controls .setting-toggle{display:grid!important;grid-template-columns:minmax(0,1fr) auto;grid-template-rows:minmax(24px,auto) 1fr;gap:8px!important;align-items:center}
.settings-controls .toggle-copy{display:contents}
.settings-controls .toggle-copy strong{grid-column:1/-1;align-self:center}
.settings-controls .toggle-copy small{grid-column:1;grid-row:2;line-height:1.5}
.settings-controls .switch{grid-column:2;grid-row:2}
.settings-controls .setting-toggle:hover,.settings-controls .setting-toggle:focus-within{border-color:#B8A0D4;background:#F7F4FC}
.settings-controls .setting-toggle:has(input:checked){border-color:#B8A0D4;background:#F3EDF9}
.settings-footer{display:flex;align-items:center;justify-content:space-between;gap:16px}
.settings-footer .settings-note{max-width:560px;padding:0;background:transparent;gap:6px}
.settings-footer .settings-apply{flex:0 0 auto;width:auto;gap:10px;white-space:nowrap}
@media(max-width:850px){.settings-controls{grid-template-columns:repeat(2,minmax(0,1fr))}.settings-footer{align-items:flex-start}}
@media(max-width:500px){.settings-controls{gap:8px}.settings-footer{flex-direction:column;gap:10px}.settings-footer .settings-apply{width:100%}}

.exercise-actions{display:flex;align-items:center;gap:8px;flex-wrap:wrap}.custom-picker{padding:14px 28px;background:#F7F4FC;border-bottom:1px solid #DDD2EC}.custom-picker form{display:flex;align-items:flex-end;flex-wrap:wrap;gap:12px}.custom-picker label{display:grid;gap:5px;font-size:11px;color:#70627C}.custom-picker input{width:130px;max-width:100%;padding:9px 10px;border:1px solid #DDD2EC;border-radius:7px;background:white;color:#30263F}.custom-picker input:focus-visible{outline:3px solid #d3a63a;outline-offset:2px}.custom-divider{padding-bottom:10px}.custom-picker #custom-error:empty{display:none}.custom-picker .text-button{padding:12px 4px}.exercise-actions button[aria-expanded="true"]{background:#EDE5F8}@media(max-width:700px){.exercise-bar{flex-wrap:wrap}.exercise-actions{gap:6px}.exercise-actions .secondary{padding:9px 11px}.custom-picker{padding:12px 16px}.custom-picker form{gap:10px}.custom-picker input{width:110px}}

.session-panel{margin-top:12px;border:1px solid #DDD2EC;border-radius:12px;background:#fff;padding:13px 18px}.session-bar{display:flex;align-items:center;justify-content:space-between;gap:10px;flex-wrap:wrap}.session-bar>strong{font-size:12px}.session-counters{display:flex;gap:8px;flex-wrap:wrap;font-size:11px}.session-counters>span{padding:6px 10px;background:#EDE5F8;border-radius:20px}.session-counters b{font-variant-numeric:tabular-nums}.session-announcement{margin:9px 0 0;color:#5E408A;font-size:12px;line-height:1.5}.session-announcement:empty{display:none}.session-panel details{margin-top:9px}.session-panel summary{font-size:11px;color:#70627C;width:fit-content;padding:4px 0}.session-panel #session-empty{font-size:12px;line-height:1.5;color:#70627C;margin:10px 0}.session-history{list-style:none;padding:0;margin:8px 0;max-height:240px;overflow:auto}.session-history li{display:flex;justify-content:space-between;align-items:baseline;gap:8px;flex-wrap:wrap;padding:9px 0;border-bottom:1px solid #EDE5F8;font-size:12px}.session-history small{font-size:10px;color:#70627C}.session-panel .text-button{font-size:11px;color:#5E408A}.setting-card select:focus-visible{outline:3px solid #7352A3;outline-offset:3px}@keyframes reward-pop{from{transform:translateY(3px);opacity:.3}to{transform:translateY(0);opacity:1}}@media(max-width:700px){.session-panel{padding:12px 15px}.session-bar{align-items:flex-start}.session-counters{gap:6px}.session-history li{flex-direction:column;gap:4px}}@media(prefers-reduced-motion:reduce){*,*::before,*::after{animation:none!important;transition:none!important;scroll-behavior:auto!important}}

.session-announcement.earned{animation:reward-pop .35s ease-out}.usage-note{display:block;max-width:760px;margin:12px auto 0;color:#70627C;font-size:10px;line-height:1.5;text-align:center}

.intro h1>[data-i18n="ui.introTitle"]{color:inherit}.language-picker{display:flex;align-items:center;gap:8px;font-size:11px;color:#70627C}.language-picker select{font:inherit;color:#30263F;background:#fff;border:1px solid #DDD2EC;border-radius:8px;padding:7px 9px;min-height:34px}.language-picker select:focus-visible{outline:3px solid #7352A3;outline-offset:3px}@media(max-width:400px){.language-picker>span{display:none}.topbar{gap:12px}.language-picker select{max-width:110px}}

.session-record-details{display:grid;gap:3px;text-align:right}.session-help{color:#70627C}@media(max-width:700px){.session-record-details{text-align:left}}

.session-points{display:flex;align-items:center;gap:7px;padding:7px 12px;border-radius:18px;background:#EDE5F8;color:#5E408A;font-size:12px}.session-points>span:first-child{font-size:23px}.session-points b{font-size:20px;font-variant-numeric:tabular-nums}.session-panel details .session-counters{margin-top:10px}.session-rules{font-size:10px;line-height:1.6;color:#70627C;margin:9px 0}.session-reward{font-size:12px;color:#5E408A;padding-top:3px}

.reward-picker{display:flex;align-items:center;gap:7px;font-size:11px;color:#70627C}.reward-picker select{font:inherit;border:1px solid #DDD2EC;border-radius:8px;padding:7px 8px;background:#fff;color:#30263F;min-height:34px}.reward-picker select:focus-visible{outline:3px solid #7352A3;outline-offset:3px}@media(max-width:700px){.reward-picker{order:3;flex-basis:100%;justify-content:space-between}}