:root{color-scheme:light;--bg:#f6f7fb;--card:#fff;--muted:#64748b;--text:#1e293b;--line:#dbe3ef;--soft:#eef0fa;--accent:#595ab9;--accentTxt:#fff;--good:#16865e;--bad:#c2414a;--note:#b76c1d}
@media(prefers-color-scheme:dark){:root{color-scheme:dark;--bg:#111723;--card:#1a2332;--muted:#a7b0c5;--text:#f2f4fb;--line:#334155;--soft:#28304b;--accent:#a6a6ff;--accentTxt:#101624;--good:#67e8b1;--bad:#ffa0a8;--note:#ffcd7c}}
*{box-sizing:border-box}html{-webkit-text-size-adjust:100%;touch-action:manipulation}body{margin:0;background:var(--bg);color:var(--text);font:16px/1.5 -apple-system,BlinkMacSystemFont,'Noto Sans SC','PingFang SC',sans-serif;overflow-x:clip}main{max-width:850px;margin:auto;padding:18px 14px 65px}button,input,select,textarea{font:inherit;color:var(--text)}button{background:var(--card);border:1px solid var(--line);border-radius:12px;padding:10px 14px;min-height:44px;font-weight:650;cursor:pointer;touch-action:manipulation}button:disabled{opacity:.45;cursor:default}.primary{background:var(--accent);color:var(--accentTxt);border-color:transparent}.soft{background:var(--soft);border-color:transparent}.danger{color:var(--bad)}button:focus-visible,input:focus-visible,select:focus-visible{outline:2px solid var(--accent);outline-offset:3px}a{color:var(--accent);text-decoration:none;font-weight:650}h1{font-size:25px;line-height:1.25;margin:0}h2{font-size:20px;margin:0 0 12px}h3{font-size:16px;margin:0}p{margin:8px 0 12px}.sub{color:var(--muted);font-size:13px}.headline{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:14px}.card{background:var(--card);border:1px solid var(--line);border-radius:19px;padding:18px;margin-bottom:15px;min-width:0}.nav{display:flex;gap:7px;flex-wrap:wrap;margin:17px 0}.nav button{flex:1 1 auto;min-width:84px;font-size:14px}.nav .selected,.chips .selected{border-color:var(--accent);background:var(--soft)}.stack{display:grid;gap:10px}.book-row{display:flex;align-items:center;gap:12px;width:100%;text-align:left;padding:15px}.book-row .icon{width:48px;height:48px;background:var(--soft);border-radius:13px;display:grid;place-items:center;flex:none;font-size:21px}.grow{flex:1;min-width:0}.book-row b,.book-row small{display:block}.book-row small{font-size:12px;color:var(--muted)}.btn-row{display:flex;flex-wrap:wrap;gap:8px;align-items:center}.btn-row button{flex:1 1 auto}.btn-row .tight{flex:0 1 auto}.grid2{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:9px}.grid3{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:9px}.stat{background:var(--bg);border-radius:12px;padding:12px 7px;text-align:center}.stat b{font-size:22px;display:block;font-variant-numeric:tabular-nums}.stat span{font-size:11px;color:var(--muted)}.bar{height:8px;border-radius:99px;background:var(--line);overflow:hidden;margin:12px 0}.bar>div{height:100%;background:var(--accent)}.pill{padding:4px 9px;border:1px solid var(--line);border-radius:100px;font-size:12px;white-space:nowrap}.formrow{display:grid;gap:5px;margin-bottom:12px}.formrow label{font-size:13px;font-weight:650}input:not([type=checkbox]):not([type=file]),select,textarea{width:100%;min-width:0;border:1px solid var(--line);background:var(--bg);border-radius:10px;padding:10px;font-size:16px}input[type=file]{max-width:100%;font-size:14px}.mutedbox{background:var(--bg);padding:12px;border-radius:11px}.notice{border-left:3px solid var(--accent);padding:9px 11px;background:var(--soft);border-radius:5px;font-size:13px;white-space:pre-wrap}.error{color:var(--bad)}.ok{color:var(--good)}.warn{color:var(--note)}.table-scroll{overflow-x:auto}.table{width:100%;border-collapse:collapse;font-size:13px}.table td,.table th{text-align:left;border-bottom:1px solid var(--line);padding:9px 7px;vertical-align:top}.table td{overflow-wrap:anywhere}.table th{white-space:nowrap}.word-hero{text-align:center;padding:26px 0 30px}.word-hero b{font-size:clamp(32px,7vw,52px);line-height:1.16;overflow-wrap:anywhere}.choices{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}.choice{text-align:left;display:flex;align-items:center;gap:12px;min-height:72px;line-height:1.45}.choice strong{width:30px;height:30px;display:grid;place-items:center;background:var(--bg);border-radius:8px;flex:none;font-size:14px}.choice.correct{border-color:var(--good);background:color-mix(in srgb,var(--good) 8%,var(--card))}.choice.wrong{border-color:var(--bad)}.answer{padding:13px;border:1px solid var(--line);border-radius:11px;margin:13px 0;overflow-wrap:anywhere}.answer.good{border-color:var(--good)}.answer.bad{border-color:var(--bad)}.after-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:9px;margin:12px 0}.after-grid button{width:100%;min-height:46px;padding:8px;font-size:14px}.record{border:1px solid var(--line);border-radius:12px;padding:11px 13px;margin-bottom:8px}.record summary{cursor:pointer;display:flex;align-items:center;gap:8px;list-style:none}.record summary::-webkit-details-marker{display:none}.record summary b{flex:1}.record summary span{font-size:13px;color:var(--muted)}.record p{font-size:13px;color:var(--muted)}.chips{display:flex;gap:7px;flex-wrap:wrap;margin:12px 0}.chips button{min-height:35px;padding:6px 11px;font-size:13px;border-radius:40px}.select-check{display:flex;gap:8px;align-items:center;padding:11px;border:1px solid var(--line);border-radius:10px}.select-check input{width:18px;height:18px}.small{font-size:12px}.footer{text-align:center;font-size:12px;color:var(--muted);padding:18px}.hidden,[hidden]{display:none!important}details>summary{cursor:pointer}ul{padding-left:20px}hr{border:0;border-top:1px solid var(--line);margin:16px 0}
@media(max-width:560px){main{padding:14px 11px 52px}.card{padding:14px;border-radius:17px}.choices{grid-template-columns:1fr}.choice{min-height:64px}.grid3{grid-template-columns:repeat(3,minmax(0,1fr))}.stat b{font-size:19px}.nav button{padding:9px 7px;min-width:65px;font-size:13px}.word-hero{padding:15px 0 22px}.btn-row button{min-width:0}.after-grid button{font-size:13px}}

/* V10: 单入口、多词书直达、系统设置内聚。 */
:root{--page-width:760px}
main{max-width:var(--page-width);padding:24px 20px 78px}
.headline{margin:0 0 22px;align-items:center}
.brand{display:flex;gap:12px;align-items:center;min-width:0}
.brand-mark{width:46px;height:46px;display:grid;place-items:center;border:1px solid var(--line);background:var(--soft);border-radius:14px;font-size:23px;flex-shrink:0}
.headline h1{font-size:27px;letter-spacing:-.4px}
.headline .sub{margin:3px 0 0;font-size:12.5px}
.icon-btn{border-radius:14px;background:var(--card);width:46px;height:46px;min-width:46px;padding:0;font-size:23px;display:grid;place-items:center}
.nav{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:9px;margin:0 0 22px}
.nav button{font-size:14px;min-width:0;padding:12px 7px;border-radius:13px;min-height:46px}
.card{padding:22px;margin-bottom:20px;border-radius:20px}
.section-heading{display:flex;align-items:flex-start;justify-content:space-between;gap:12px;margin-bottom:17px}
.section-heading h2{margin-bottom:2px;font-size:20px}
.section-heading p{margin:2px 0 0}
.counter{color:var(--muted);background:var(--bg);border:1px solid var(--line);border-radius:999px;padding:6px 10px;font-size:12px;white-space:nowrap}
.book-row{border-radius:15px;padding:15px 14px;min-height:90px;gap:14px;background:var(--bg);transition:border-color .14s}
.book-row:active{border-color:var(--accent)}
.book-row .icon{height:52px;width:52px;border-radius:14px;font-size:24px}
.book-row b{font-size:16px;line-height:1.3;overflow-wrap:anywhere}
.book-row small{font-size:12px;line-height:1.6;margin-top:6px}
.book-row .arrow{color:var(--muted);font-size:27px;flex:none}
.stack{gap:12px}
.add-book{display:block;width:100%;margin-top:16px;text-align:center;border:1px dashed var(--line);background:transparent;color:var(--accent);font-size:14px;padding:14px 8px;min-height:50px}
.focus-study .nav,.focus-detail .nav{display:none}
.focus-study .headline,.focus-detail .headline{margin-bottom:16px}
.study-navigation,.section-back,.settings-heading{display:flex;align-items:center;justify-content:space-between;gap:10px;margin-bottom:14px}
.back-link{min-height:42px;padding:9px 12px;font-size:13px;border-radius:12px;background:var(--bg)}
.study-navigation .sub{margin:0}
.settings-heading h2{margin:0}
.quiz-mode-row{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:8px;margin:18px 0}
.quiz-mode-row button{font-size:13px;min-width:0;padding:10px 6px}
.settings-links{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;margin:14px 0}
.settings-links a{border:1px solid var(--line);padding:12px 10px;text-align:center;border-radius:12px;background:var(--bg);font-size:13px;line-height:1.5}
#view-settings>.card{margin-bottom:18px}
#view-import .card,#view-records>.card{padding-block:22px}
#view-mixed>.card{margin-bottom:16px}
#view-mixed .select-check{margin-bottom:2px}
@media(max-width:560px){main{padding:20px 14px calc(72px + env(safe-area-inset-bottom))}.headline{margin-bottom:19px}.headline h1{font-size:24px}.brand-mark{width:41px;height:41px;font-size:21px}.icon-btn{width:42px;height:42px;min-width:42px}.card{padding:18px 16px;border-radius:17px;margin-bottom:16px}.nav{gap:8px;margin-bottom:18px}.nav button{padding:10px 5px;font-size:13px}.book-row{padding:13px 11px;min-height:87px;gap:11px}.book-row .icon{width:45px;height:45px;font-size:21px}.book-row b{font-size:15px}.book-row small{font-size:11.5px}.settings-links{grid-template-columns:1fr}.btn-row{gap:9px}.btn-row button{font-size:14px}}
@media(max-width:360px){.headline h1{font-size:21px}.card{padding:14px 12px}.book-row{gap:8px}.brand{gap:9px}.brand-mark{width:38px;height:38px}}

/* V10.1 iPhone Safari: do not anchor the scroll offset to elements that
   are replaced when a new question appears. The click handlers position
   the new word explicitly instead. */
html,body,.quiz,.word-hero,#customQuizInner,#mixedQuiz{overflow-anchor:none}
html{scroll-behavior:auto!important}

@media(max-width:560px){body:has(#view-study:not(.hidden)) main,body:has(#view-mixed:not(.hidden)) main{padding-bottom:max(340px,42svh)}}

/* V10.3: per-book numeric range practice, light/dark and iPhone friendly. */
.range-custom-control{background:var(--bg);border:1px solid var(--line);padding:14px;border-radius:15px;margin-top:14px}
.range-heading{display:flex;justify-content:space-between;align-items:center;gap:8px;flex-wrap:wrap}
.range-heading strong{font-size:15px}.range-heading .sub{margin:0}
.range-input-row{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;margin:11px 0}
.range-input-row label{display:flex;align-items:center;gap:8px;min-width:0;font-size:13px;white-space:nowrap}
.range-input-row input{min-width:0;width:100%;max-width:100%;height:44px;font-size:16px;padding:8px!important;background:var(--card)!important}
.range-action-row{display:flex;gap:8px;flex-wrap:wrap}
.range-action-row button{flex:1 1 112px;min-height:43px;padding:8px 9px;font-size:13px}
.range-info{color:var(--muted);font-size:12px;line-height:1.55;margin:10px 0 0}
#customQuizInner>.range-info{border-bottom:1px solid var(--line);padding-bottom:9px}

/* XY’s-vocab: new-origin first-visit migration guide; learning logic remains V10.3. */
.migration-panel{border:1px solid var(--accent);background:var(--soft);padding:14px 14px 15px;border-radius:14px;margin:0 0 20px}
.migration-panel-heading{display:flex;gap:7px;justify-content:space-between;align-items:center;flex-wrap:wrap}
.migration-panel-heading strong{font-size:15px}
.migration-label{font-size:11px;color:var(--muted)}
.migration-panel p{font-size:13px;line-height:1.6;margin:8px 0 12px}
.migration-actions{display:flex;flex-wrap:wrap;gap:8px}
.migration-actions>*{display:inline-flex;align-items:center;justify-content:center;text-align:center;flex:1 1 138px;min-height:43px;border-radius:10px;padding:8px 9px;font-size:13px}
.migration-link{border:1px solid var(--line);background:var(--card);color:var(--text)}
@media(max-width:560px){.migration-panel{padding:12px;margin-bottom:16px}.migration-actions>*{flex:1 1 100%}}


/* V10.5 - EX1680 visual standard shared by all future imported books. */
.classic-progress-card{padding:20px}
.classic-section-heading,.classic-smallbar,.classic-quiz-head{display:flex;align-items:center;justify-content:space-between;gap:10px}
.classic-section-heading h2{font-size:23px;margin:0 0 8px}
.classic-smallbar{font-size:17px;margin-bottom:3px}
.classic-progress{height:9px;background:var(--line);border-radius:100px;overflow:hidden;margin:16px 0 8px}
.classic-progress>span{height:100%;display:block;background:var(--accent);border-radius:100px;transition:width .15s}
.classic-progress-text{font-size:14px;line-height:1.6;white-space:pre-line;margin:9px 0 16px}
.classic-stat-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:10px}
.classic-stat-grid .stat{border-radius:12px;min-width:0;padding:12px 5px;min-height:104px;display:flex;flex-direction:column;align-items:center;justify-content:center}
.classic-stat-grid .stat b{font-size:21px;line-height:1.18}
.classic-stat-grid .stat>span{font-size:12px;margin-top:8px;line-height:1.35}
.classic-pending-card{font:inherit;color:var(--text);cursor:pointer;text-align:center;width:100%;border:1px solid var(--line);background:var(--bg)}
.classic-pending-card:hover,.classic-pending-card:focus-visible{border-color:var(--accent);background:var(--soft)}
.classic-pending-card small{color:var(--accent);font-size:11px;font-weight:700;margin-top:4px}
.classic-auto-save{margin-top:17px;font-size:13px}
.classic-quiz-card{padding:20px 20px 18px}
.classic-quiz-head{font-size:16px;line-height:1.35}
.classic-quiz-head>.sub{text-align:right;max-width:55%}
.classic-title-word{text-align:center;font-size:clamp(32px,7vw,52px);font-weight:800;line-height:1.16;letter-spacing:-.02em;padding:30px 0 0;overflow-wrap:anywhere}
.classic-title-word b{font-weight:800}
.classic-meta{text-align:center;color:var(--muted);font-size:14px;font-weight:400;letter-spacing:0;margin:7px 0 25px}
.classic-recall{border:1px solid var(--line);border-radius:15px;padding:17px 13px;text-align:center;margin:0 0 15px;background:var(--bg)}
.classic-recall strong{font-size:17px}
.classic-recall .sub{font-size:13px;line-height:1.6;margin:6px 0 14px}
.classic-toolbar{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;margin-top:16px}
.classic-toolbar button{min-width:0;min-height:52px;font-size:15px;padding:9px 7px}
.classic-choices{display:grid;grid-template-columns:1fr;gap:10px}
.classic-choice{display:grid;grid-template-columns:32px minmax(0,1fr);gap:12px;align-items:center;min-height:68px;width:100%;text-align:left;font-weight:650;padding:12px 14px;line-height:1.45;background:var(--card);white-space:normal}
.classic-key{display:grid;place-items:center;background:var(--bg);border-radius:9px;width:32px;height:32px;color:var(--muted);font-weight:800;font-size:14px}
.classic-choice-text{display:block;min-width:0;overflow-wrap:anywhere}
.classic-choice.isCorrect{border-color:var(--good);background:color-mix(in srgb,var(--good) 9%,var(--card))}
.classic-choice.isWrong{border-color:var(--bad)}
.classic-feed{font-size:14px;border:1px solid var(--line);border-radius:11px;padding:13px;margin:14px 0;line-height:1.55;overflow-wrap:anywhere}
.classic-feed.good{border-color:var(--good)}
.classic-feed.bad{border-color:var(--bad)}
.classic-post-buttons{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;margin-top:10px}
.classic-post-buttons button{min-width:0;min-height:48px;padding:10px 9px;font-size:14px;line-height:1.25;white-space:nowrap}
.classic-quiz-card .quiz-mode-row{margin:18px 0 0}
.classic-quiz-card .quiz-mode-row button{min-height:51px;font-weight:650;font-size:14px}
.classic-range-wrap{padding:16px 20px;margin-top:0}
.classic-range-wrap summary{font-size:15px;font-weight:700;display:flex;align-items:center;justify-content:space-between;gap:7px;list-style:none}
.classic-range-wrap summary::-webkit-details-marker{display:none}
.classic-range-wrap summary::before{content:'▸';margin-right:4px;color:var(--accent)}
.classic-range-wrap[open] summary::before{content:'▾'}
.classic-range-wrap summary .sub{font-size:12px;font-weight:400;text-align:right}
.classic-range-wrap .range-custom-control{margin-top:13px;background:var(--bg)}
.classic-hint{font-size:12px;text-align:center;margin:16px 0}
.classic-weak-dialog{color:var(--text);background:var(--card);border:1px solid var(--line);border-radius:17px;padding:17px;position:fixed;inset:0;margin:auto;width:min(640px,calc(100vw - 22px));max-height:min(85dvh,780px);overflow-y:auto}
.classic-weak-dialog::backdrop{background:#0009}
.classic-dialog-header{display:flex;gap:12px;align-items:center;justify-content:space-between}
.classic-dialog-header h2{margin:0;font-size:19px;min-width:0;overflow-wrap:anywhere}
.classic-dialog-header button{min-width:43px;padding:4px}
.classic-weak-controls{margin:14px 0 8px}
.classic-weak-filters,.classic-weak-exports{display:flex;gap:8px;flex-wrap:wrap;margin-top:10px}
.classic-weak-filters button{min-height:39px;flex:1;padding:7px 9px;font-size:13px}
.classic-weak-filters button.chosen{background:var(--soft);border-color:var(--accent)}
.classic-weak-list{max-height:41dvh;overflow:auto;margin:12px 0;border-top:1px solid var(--line)}
.classic-weak-item{padding:13px 0;border-bottom:1px solid var(--line);overflow-wrap:anywhere}
.classic-weak-line{display:flex;align-items:center;justify-content:space-between;gap:10px}
.classic-weak-line b{font-size:17px}
.classic-weak-line>.sub{font-size:12px;text-align:right}
.classic-weak-item p{margin:6px 0;color:var(--text);font-size:14px}
.classic-weak-item>.sub{font-size:12px}
.classic-weak-exports{display:grid;grid-template-columns:repeat(2,minmax(0,1fr))}
.classic-weak-exports button{padding:8px;font-size:13px}
@media(max-width:560px){
 .classic-progress-card,.classic-quiz-card{padding:16px 15px}
 .classic-section-heading h2{font-size:22px}
 .classic-stat-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:9px}
 .classic-stat-grid .stat{min-height:93px}
 .classic-stat-grid .stat b{font-size:22px}
 .classic-title-word{padding:22px 0 0}
 .classic-choice{min-height:64px;grid-template-columns:30px minmax(0,1fr);gap:11px;padding:12px 13px}
 .classic-key{width:30px;height:30px}
 .classic-toolbar button{font-size:14px}
 .classic-recall{padding:15px 12px}
 .classic-range-wrap{padding:15px 13px}
 .classic-range-wrap summary .sub{font-size:11px}
 .classic-quiz-head{font-size:14px}
}
@media(max-width:350px){.classic-toolbar{gap:8px}.classic-toolbar button{font-size:13px}.classic-stat-grid .stat b{font-size:20px}}