:root{--paper:#f5f3ec;--card:#fffefb;--ink:#30352e;--muted:#6f7468;--line:#e3e5da;--green:#38674e;--soft:#edf2e9;--red:#a34f3e;--red-soft:#f8eee7;--radius:22px;--font:"Segoe UI","Microsoft YaHei",sans-serif}

*{box-sizing:border-box}
body{margin:0;background:var(--paper);color:var(--ink);font-family:var(--font);font-size:15px;line-height:1.6;-webkit-font-smoothing:antialiased}
button,input,select{font:inherit}
button,a,input,select{-webkit-tap-highlight-color:transparent}
button{cursor:pointer;color:inherit;background:none;border:0;min-height:44px;transition:background .16s,color .16s,border-color .16s,opacity .16s}
button:disabled{cursor:default;opacity:.38}
button:not(:disabled):active{opacity:.7}
button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible{outline:2px solid var(--green);outline-offset:4px}
a{color:inherit;text-decoration:none}
svg{display:block}
.site-header{max-width:1104px;margin:auto;display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:12px;padding:34px 32px}
.brand{display:flex;align-items:center;gap:12px;font-size:19px;font-weight:600;letter-spacing:1px}
.brand svg{color:var(--green)}
.utility-nav{display:flex;gap:20px}
.utility-nav button{padding:6px 8px;color:var(--muted);font-size:14px}
.utility-nav button:hover{color:var(--green)}
.utility-nav .legacy-link{display:inline-flex;align-items:center;justify-content:center;min-height:44px;padding:6px 13px;border:1px solid var(--green);border-radius:9px;background:var(--soft);color:var(--green);font-size:14px;font-weight:600;white-space:nowrap}
.utility-nav .legacy-link:hover{background:var(--green);color:var(--card)}
main{padding:35px 24px 42px}
.workspace{max-width:658px;margin:auto}
.context-line{display:flex;align-items:center;justify-content:space-between;padding:0 5px 12px;font-size:12px;letter-spacing:.5px;color:var(--muted)}
.context-line button{font-size:13px;min-height:32px;padding:0}
.context-line button:after{content:'⌄';margin-left:9px}
.study-card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);box-shadow:0 4px 5px -4px #343d2412,0 26px 70px -42px #3b452b48;overflow:hidden}
.main-tabs{display:grid;grid-template-columns:repeat(4,1fr);padding:13px 26px 0;border-bottom:1px solid var(--line);gap:14px}
.main-tabs button{position:relative;padding:15px 0 21px;color:var(--muted);letter-spacing:2px;font-size:16px}
.main-tabs button.active{color:var(--green);font-weight:600}
.main-tabs button.active:after{content:'';position:absolute;bottom:-1px;left:28%;right:28%;height:3px;border-radius:3px;background:var(--green)}
.subbar{min-height:69px;display:flex;align-items:center;justify-content:space-between;gap:12px;padding:16px 30px 8px}
.subtabs{display:flex;gap:5px}
.subtabs button{font-size:13px;min-height:36px;padding:5px 15px;border-radius:8px;color:var(--muted)}
.subtabs button.active{background:var(--soft);color:var(--green);font-weight:600}
.mode-note{font-size:12px;color:var(--muted)}
.dot-status{display:inline-flex;align-items:center;gap:6px}
.dot-status:before{content:'';width:5px;height:5px;background:var(--green);border-radius:50%}
.exercise{min-height:360px;display:flex;flex-direction:column;align-items:center;justify-content:center;padding:22px 40px 32px;text-align:center}
.eyebrow{font-size:12px;letter-spacing:2px;color:var(--muted);margin:0 0 18px}
.prompt{font-size:34px;font-weight:500;line-height:1.45;margin:0;letter-spacing:2px}
.part-of-speech{font:italic 14px Georgia,serif;color:var(--muted);margin-top:7px}
.answer-form{margin-top:36px;width:100%;max-width:350px}
.answer-form label{display:block;font-size:12px;color:var(--muted);text-align:left;margin-bottom:8px}
.answer-input{width:100%;min-height:52px;border:0;border-bottom:1px solid #aeb7a3;background:transparent;text-align:center;border-radius:0;color:var(--ink);font:25px Georgia,serif;padding:8px 10px;letter-spacing:1px}
.answer-input::placeholder{font:15px var(--font);letter-spacing:.5px;color:var(--muted)}
.answer-input:focus{outline:none;border-bottom:2px solid var(--green)}
.answer-input:focus-visible{outline:2px solid var(--green);outline-offset:5px;border-radius:3px}
.form-actions{display:flex;justify-content:center;align-items:center;gap:18px;margin-top:24px}
.primary,.secondary{min-height:46px;padding:10px 28px;border-radius:10px;font-size:14px}
.primary{background:var(--green);color:white}
.primary:hover{background:#2c563f}
.secondary{border:1px solid #cfd6c7;background:var(--card)}
.secondary:hover{background:var(--soft)}
.text-button{color:var(--muted);font-size:13px;padding:8px 12px}
.text-button:hover{color:var(--green)}
.exercise-footer{border-top:1px solid var(--line);margin:0 30px;min-height:69px;display:flex;align-items:center;justify-content:space-between;gap:10px;color:var(--muted);font-size:12px}
.exercise-footer button{padding:8px 4px;font-size:13px}
.page-count{font-variant-numeric:tabular-nums;letter-spacing:2px}
.workspace-foot{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:11px 4px;color:var(--muted);font-size:11px}
.workspace-foot button{font-size:11px;min-height:32px;padding:0}
.english-line{display:flex;align-items:center;justify-content:center;gap:13px;width:100%}
.english{font:52px/1.3 Georgia,"Times New Roman",serif;letter-spacing:-1px;overflow-wrap:anywhere;margin:0}
.sound-button{display:inline-grid;place-items:center;border:1px solid var(--line);border-radius:50%;width:44px;height:44px;flex:0 0 44px;color:var(--muted)}
.sound-button:hover{border-color:var(--green);color:var(--green);background:var(--soft)}
.phonetic{font:16px Georgia,serif;color:var(--muted);margin:13px 0 24px}
.reveal-space{min-height:110px;display:flex;flex-direction:column;justify-content:center;margin-top:5px;width:100%}
.reveal-button{color:var(--muted);border-bottom:1px dashed #c8cfbf;align-self:center;padding:4px 8px;font-size:14px}
.meaning{font-size:23px;line-height:1.5;margin:9px 0 15px}
.rating-row{display:flex;justify-content:center;gap:12px;width:100%;margin-top:18px}
.rating-row button{width:150px}
.feedback{margin-top:26px;width:100%;max-width:350px;padding:16px 20px;border-radius:12px;background:var(--soft);font-size:14px}
.feedback.wrong{background:var(--red-soft);color:var(--red)}
.feedback p{margin:3px 0}
.correct-word{font:27px Georgia,serif;letter-spacing:1px;color:var(--ink)}
.feedback .your-answer{font-size:12px;overflow-wrap:anywhere}
.feedback .primary{margin-top:15px}
.round-dots{display:flex;justify-content:center;gap:7px;margin:15px 0 0}
.round-dots i{height:6px;width:6px;background:#d7ddcf;border-radius:50%}
.round-dots i.filled{background:var(--green)}
.round-caption{font-size:12px;color:var(--muted);margin-top:7px}
.finish-icon{height:48px;width:48px;border:1px solid #cbd9c3;border-radius:50%;display:grid;place-items:center;color:var(--green);font-size:23px;margin-bottom:22px}
.finish-title{font-size:27px;font-weight:500;margin:0}
.quiet{color:var(--muted);font-size:13px;line-height:1.9}
.finish-actions{display:flex;flex-direction:column;gap:8px;margin-top:22px;min-width:190px}
.content-pad{min-height:360px;padding:25px 34px 31px}
.content-title{font-size:23px;font-weight:500;margin:0 0 8px}
.sheets{display:flex;gap:16px;justify-content:center;margin:24px 0 21px}
.sheet{flex:1;max-width:142px;min-width:0;aspect-ratio:.74;background:#fff;border:1px solid #dce1d4;border-radius:3px;padding:15px 11px;box-shadow:0 4px 10px #35432908;position:relative}
.sheet .sheet-title{font-size:11px;color:#4d5944;margin-bottom:15px;font-weight:600;display:block}
.sheet-lines{display:grid;grid-template-columns:1fr 1fr;gap:8px 6px}
.sheet-lines i{display:block;height:3px;background:#e4e7de}
.sheet-lines i:nth-child(3n){width:70%}
.sheet:after{content:'手默单词';position:absolute;bottom:10px;left:11px;font-size:7px;color:#84917b}
.download-actions{text-align:center}
.individual-downloads{display:flex;justify-content:center;gap:12px;margin-top:9px}
.individual-downloads button{font-size:12px;color:var(--muted);padding:4px}
.small-label{font-size:12px;color:var(--muted);display:flex;align-items:center;gap:7px}
.small-label svg{width:14px;height:14px}
.grade-options{display:flex;gap:9px;margin-bottom:20px}
.grade-options button{padding:6px 15px;border:1px solid var(--line);border-radius:8px;font-size:13px}
.grade-options .active{background:var(--soft);color:var(--green);border-color:#cbd6c2}
.grade-list{max-height:230px;overflow:auto;margin:15px 0 18px}
.grade-row{display:flex;align-items:center;justify-content:space-between;gap:10px;padding:7px 2px;border-bottom:1px solid var(--line)}
.grade-row .word-name{font:18px Georgia,serif}
.grade-row button{min-width:62px;border-radius:8px;color:var(--green);background:var(--soft);min-height:36px;font-size:12px}
.grade-row button.wrong{color:var(--red);background:var(--red-soft)}
.upload{display:grid;place-items:center;text-align:center;padding:30px 12px;border:1px dashed #bfcab5;border-radius:12px;min-height:142px;margin:18px 0;cursor:pointer}
.upload input{max-width:100%;font-size:12px;margin-top:13px}
.photo-preview{max-height:120px;max-width:100%;object-fit:contain;display:block;margin:12px auto}
.locked{text-align:center}
.locked .quiet{max-width:300px;margin:13px auto}
.history-list{max-height:305px;overflow:auto;margin-top:15px}
.history-row{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:12px 2px;border-bottom:1px solid var(--line)}
.history-row h3{font:21px Georgia,serif;margin:0 0 3px}
.history-row p{font-size:12px;color:var(--muted);margin:0}
.history-row button{font-size:12px;border:1px solid var(--line);border-radius:8px;padding:4px 15px;white-space:nowrap}
.search{width:100%;min-height:44px;border:1px solid var(--line);border-radius:9px;background:var(--card);padding:9px 13px;color:var(--ink)}
dialog{border:1px solid var(--line);border-radius:20px;padding:0;width:min(530px,calc(100% - 32px));max-height:85dvh;background:var(--card);color:var(--ink);box-shadow:0 30px 100px #1e2b2440}
dialog::backdrop{background:#25332955;backdrop-filter:blur(3px)}
.panel-head{display:flex;align-items:center;justify-content:space-between;padding:19px 23px;border-bottom:1px solid var(--line);position:sticky;top:0;background:var(--card);z-index:2}
.panel-head h2{font-size:19px;font-weight:500;margin:0}
.icon-button{height:44px;width:44px;font-size:25px;color:var(--muted);border-radius:50%}
.icon-button:hover{background:var(--soft)}
#panel-body{padding:20px 26px 28px}
.book-choice{display:block;text-align:left;width:100%;border:1px solid var(--line);border-radius:12px;padding:16px;margin:12px 0}
.book-choice.selected{border-color:var(--green);background:var(--soft)}
.book-choice strong{font-size:15px;font-weight:500;display:block}
.book-choice span{font-size:12px;color:var(--muted);display:block;margin-top:5px}
.bank-row{padding:13px 0;border-bottom:1px solid var(--line);display:flex;justify-content:space-between;gap:15px}
.bank-row strong{font:21px Georgia,serif}
.bank-row p{margin:3px 0;font-size:12px;color:var(--muted)}
.word-status{font-size:11px;white-space:nowrap;color:var(--green);padding-top:3px}
.account-mark{display:flex;align-items:center;gap:14px;margin:5px 0 22px}
.avatar{height:44px;width:44px;border-radius:50%;background:var(--soft);color:var(--green);display:grid;place-items:center;font:23px Georgia,serif}
.account-mark p{margin:0;font-size:12px;color:var(--muted)}
.account-line{display:flex;justify-content:space-between;padding:13px 0;border-bottom:1px solid var(--line);font-size:14px}
.about-note{font-size:13px;line-height:1.9;color:var(--muted)}
.about-note p{margin:0 0 15px}
.demo-controls{padding-top:14px;border-top:1px solid var(--line);margin-top:21px}
.demo-controls button{display:block;margin:8px 0;width:100%;text-align:left;padding:10px 14px;border:1px solid var(--line);border-radius:9px;font-size:13px}
.badge{display:inline-block;padding:2px 7px;border-radius:5px;background:var(--soft);font-size:11px;color:var(--green);margin-left:8px}
.primary.full{width:100%}
.space-top{margin-top:20px}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
#toast{position:fixed;bottom:30px;left:50%;transform:translateX(-50%) translateY(12px);background:var(--ink);color:white;border-radius:10px;max-width:calc(100% - 40px);padding:11px 19px;font-size:13px;opacity:0;pointer-events:none;transition:opacity .2s,transform .2s;z-index:10;text-align:center}
#toast.visible{opacity:1;transform:translateX(-50%) translateY(0)}
.notice-inline{padding:10px 13px;background:var(--soft);border-radius:8px;font-size:12px;color:var(--green);margin:12px 0}

@media(min-width:1500px){main{padding-top:60px}
}
@media(max-width:600px){.site-header{padding:19px 20px}
.brand{font-size:17px;gap:8px}
.brand svg{width:26px;height:26px}
.utility-nav{gap:3px}
.utility-nav button{font-size:13px;padding:6px}
.utility-nav .legacy-link{font-size:13px;padding:6px 8px}
main{padding:18px 16px 25px}
.context-line{padding-bottom:9px}
.study-card{border-radius:18px}
.main-tabs{padding:7px 13px 0;gap:4px}
.main-tabs button{font-size:15px;padding:13px 0 18px}
.subbar{padding:14px 19px 7px;min-height:63px}
.subtabs button{padding:5px 12px}
.mode-note{font-size:11px}
.exercise{min-height:340px;padding:20px 22px 27px}
.prompt{font-size:30px}
.answer-form{max-width:290px;margin-top:29px}
.english{font-size:42px}
.english-line{gap:9px}
.sound-button{width:40px;height:44px;flex-basis:40px}
.exercise-footer{margin:0 20px;min-height:62px}
.content-pad{padding:19px 22px 25px;min-height:340px}
.sheets{gap:9px;margin:22px 0}
.sheet{padding:12px 7px}
.sheet .sheet-title{font-size:10px}
.individual-downloads{gap:8px}
.workspace-foot{font-size:10px;gap:8px}
.workspace-foot button{font-size:10px}
.content-title{font-size:22px}
.rating-row button{padding:10px 16px}
.finish-title{font-size:25px}
.meaning{font-size:21px}
#panel-body{padding:18px 21px 24px}
}
@media(max-height:640px){main{padding-top:8px}
.site-header{padding-top:14px;padding-bottom:12px}
.exercise{min-height:280px}
.answer-form{margin-top:20px}
}
@media(prefers-reduced-motion:reduce){*,*:before,*:after{transition:none!important;animation:none!important;scroll-behavior:auto!important}
}


/* Keep secondary controls comfortable on touch screens. */
.subtabs button,.grade-row button{min-height:44px}
.context-line button{min-height:44px}
.workspace-foot button{min-height:44px}
.sound-button{min-width:44px}
button{touch-action:manipulation}
main{padding-bottom:max(25px,env(safe-area-inset-bottom))}


.grade-row .word-name{overflow-wrap:anywhere}.grade-row small{display:block}
.sheet-links{display:flex;gap:12px;justify-content:center;flex-wrap:wrap;margin:20px 0}
.sheet-links a{padding:10px 14px;border:1px solid var(--line);border-radius:8px}
.login-form{display:grid;gap:12px}.login-form input{padding:10px;border:1px solid var(--line);border-radius:8px;min-width:0}
.workspace-foot a{padding:8px 0}body.busy #card-content button,body.busy #card-content input{pointer-events:none;opacity:.55}
body.busy.navigation-pending #answer,body.busy.navigation-pending .answer-form button{pointer-events:auto;opacity:1}
.grade-list{max-height:420px;overflow:auto}.sheet-links .primary{color:white}
.consolidation-export{display:flex;justify-content:flex-end;padding:0 24px}.consolidation-export button{font-size:12px}
.learning-switch{display:flex;justify-content:center;gap:8px;padding:4px 20px}
.learning-switch button{padding:6px 16px;border-radius:8px;color:var(--muted);font-size:13px}
.learning-switch button.active{background:var(--soft);color:var(--green);font-weight:600}
.learning-card .phonetic{margin-bottom:8px}.learning-card .meaning{font-size:22px}
.learning-notes{width:100%;text-align:left;border-top:1px solid var(--line);margin-top:15px;overflow-wrap:anywhere}
.learning-notes>div{padding:12px 0;border-bottom:1px solid var(--line)}
.learning-notes p{margin:5px 0;white-space:pre-line}.learning-notes [lang=en]{font-size:18px}
.letter-keyboard{margin-top:18px;user-select:none}.key-row{display:flex;justify-content:center;gap:4px;margin:5px 0}
.key-row button{flex:1;max-width:36px;min-width:0;min-height:44px;padding:0;background:var(--soft);border:1px solid var(--line);border-radius:6px;font-size:17px}
.key-row button:active{background:var(--green);color:white}.key-row.symbols button{max-width:60px;font-size:13px}
.keyboard-help{font-size:11px;margin:8px 0}.answer-form .form-actions{margin-top:12px}
@media(max-width:480px){.exercise:has(.letter-keyboard){padding:16px 12px 20px}.answer-form{max-width:100%;margin-top:18px}.exercise:has(.letter-keyboard) .prompt{font-size:26px}.key-row{gap:3px}.learning-card{padding-left:22px;padding-right:22px}}