:root{--ink:#122620;--cream:#f2eee3;--paper:#fffdf8;--jade:#2d6e61;--jade-light:#dcece5;--coral:#df6a48;--gold:#bc954e;--muted:#738079;--line:rgba(18,38,32,.14);--shadow:0 22px 70px rgba(32,49,42,.09)}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--cream);color:var(--ink);font-family:Arial,"PingFang SC","Microsoft YaHei",sans-serif}.app-shell{min-height:100vh;background:radial-gradient(circle at 91% 4%,rgba(45,110,97,.17),transparent 28%),radial-gradient(circle at 5% 90%,rgba(223,106,72,.10),transparent 24%),linear-gradient(180deg,#f7f3ea,#eee8da);padding-bottom:44px}.topbar{height:76px;padding:0 clamp(20px,5vw,76px);display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line);background:rgba(255,253,248,.72);backdrop-filter:blur(16px)}.brand{display:flex;align-items:center;gap:13px;color:inherit;text-decoration:none}.brand-mark{width:41px;height:41px;display:grid;place-items:center;border-radius:11px;background:var(--ink);color:white;font:italic 700 22px Georgia,serif;box-shadow:5px 5px 0 var(--coral)}.brand b{display:block;font:700 16px Georgia,"Songti SC",serif}.brand small{display:block;margin-top:3px;color:var(--muted);font-size:9px;letter-spacing:.16em;text-transform:uppercase}.session-stats{display:flex;gap:8px}.session-stats>span{min-width:82px;padding:8px 12px;border-left:1px solid var(--line)}.session-stats small{display:block;color:var(--muted);font-size:9px}.session-stats b{display:block;margin-top:3px;font:700 16px Georgia,serif}.session-stats i{font-style:normal}.intro{max-width:1380px;margin:auto;padding:36px clamp(20px,5vw,76px) 24px;display:flex;justify-content:space-between;align-items:flex-end;gap:42px}.eyebrow{margin:0 0 10px;color:var(--coral);font-size:10px;font-weight:800;letter-spacing:.15em}.intro h1{margin:0;font:700 clamp(36px,4.5vw,66px)/1 Georgia,"Songti SC",serif;letter-spacing:-.035em}.intro h1 em{color:var(--jade);font-style:normal}.intro-copy{max-width:440px;margin:0 0 5px;color:#5e6c66;font-size:13px;line-height:1.8}.training-layout{max-width:1380px;margin:auto;padding:0 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b,.level-option small{display:block}.level-option b{font-size:13px}.level-option small{margin-top:4px;color:var(--muted);font-size:10px}.level-option input:checked+span{border-color:rgba(45,110,97,.55);background:var(--jade-light);box-shadow:inset 3px 0 var(--jade)}.level-option input:focus-visible+span{outline:3px solid rgba(45,110,97,.2)}.sound-mode{margin-top:16px;padding-top:16px;border-top:1px solid #e8e3d8;display:flex;align-items:center;justify-content:space-between}.sound-mode b,.sound-mode small{display:block}.sound-mode b{font-size:11px}.sound-mode small{margin-top:4px;color:var(--muted);font-size:10px}.toggle{width:43px;height:24px;border:0;border-radius:20px;background:#d7d6cf;padding:3px;cursor:pointer;transition:.2s}.toggle span{display:block;width:18px;height:18px;border-radius:50%;background:white;box-shadow:0 2px 5px #999;transition:.2s}.toggle[aria-checked="true"]{background:var(--jade)}.toggle[aria-checked="true"] span{transform:translateX(19px)}.shortcut-note{display:grid;grid-template-columns:auto 1fr;align-items:center;gap:7px 9px;margin-top:20px;padding:11px;border-radius:11px;background:#f0ede5;color:var(--muted);font-size:9px}.shortcut-note kbd{min-width:38px;border:1px solid #d7d2c7;border-bottom-width:2px;border-radius:5px;background:#fff;padding:3px 5px;text-align:center;color:var(--ink);font:700 9px inherit}.practice-card{border-radius:22px;overflow:hidden;min-width:0}.question-head{min-height:62px;padding:0 21px;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid #e8e3d8}.attempts{display:flex;align-items:center;gap:4px}.attempts>span{width:7px;height:7px;border-radius:50%;background:var(--coral)}.attempts>span.used{background:#ddd8cf}.attempts small{margin-left:5px;color:var(--muted);font-size:9px}.listening-stage{min-height:270px;display:grid;place-items:center;align-content:center;position:relative;overflow:hidden;background:linear-gradient(180deg,#fffefa,#faf7ef)}.sound-rings{position:absolute;inset:0;display:grid;place-items:center;pointer-events:none}.sound-rings i{position:absolute;width:120px;height:120px;border:1px solid rgba(45,110,97,.12);border-radius:50%}.sound-rings i:nth-child(2){width:190px;height:190px}.sound-rings i:nth-child(3){width:260px;height:260px}.listening-stage.playing .sound-rings i{animation:pulse 1.5s ease-out infinite}.listening-stage.playing .sound-rings i:nth-child(2){animation-delay:.15s}.listening-stage.playing .sound-rings i:nth-child(3){animation-delay:.3s}@keyframes pulse{0%{transform:scale(.75);opacity:0}35%{opacity:1}100%{transform:scale(1.15);opacity:0}}.play-button{position:relative;z-index:2;width:116px;height:116px;border:0;border-radius:50%;background:var(--ink);color:white;box-shadow:0 15px 35px rgba(18,38,32,.25);cursor:pointer;transition:transform .15s,background .15s}.play-button:hover{transform:translateY(-2px);background:#1c3b32}.play-button:active{transform:scale(.98)}.play-button svg{display:block;width:30px;margin:0 auto 5px;fill:currentColor}.play-button>span{display:block;font-weight:800;font-size:12px}.play-button small{display:block;margin-top:5px;color:#bad0c7;font-size:9px}.listening-stage>p{position:relative;z-index:2;margin:20px 0 0;color:var(--muted);font-size:10px}.answer-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:9px;padding:15px 18px 18px;border-top:1px solid #eee9de}.answer-button{position:relative;border:1px solid #dedad0;border-radius:13px;background:white;padding:14px 10px;text-align:left;color:var(--ink);cursor:pointer;transition:.16s}.answer-button:hover{border-color:var(--jade);transform:translateY(-2px)}.answer-button:disabled{cursor:default;transform:none}.answer-button strong{display:block;font:700 15px Georgia,"Songti SC",serif}.answer-button small{display:block;margin-top:5px;color:var(--muted);font-size:9px}.answer-button .key{position:absolute;right:8px;top:8px;width:18px;height:18px;display:grid;place-items:center;border-radius:5px;background:#f0ede6;color:#839089;font-size:8px}.answer-button.correct{border-color:var(--jade);background:var(--jade-light)}.answer-button.wrong{border-color:var(--coral);background:#fff0ea}.feedback{margin:0 18px 18px;padding:16px;border-radius:14px;background:#edf5f1;display:grid;grid-template-columns:38px 1fr auto;align-items:center;gap:13px}.feedback[hidden]{display:none}.feedback.wrong{background:#fff0ea}.feedback-icon{width:36px;height:36px;border-radius:50%;display:grid;place-items:center;background:var(--jade);color:white}.feedback-icon::before{content:"✓";font-weight:900}.feedback.wrong .feedback-icon{background:var(--coral)}.feedback.wrong .feedback-icon::before{content:"×"}.feedback-copy>p{margin:0;color:var(--muted);font-size:9px}.feedback-copy>p:first-child{color:var(--jade);font-weight:800;letter-spacing:.08em}.feedback.wrong .feedback-copy>p:first-child{color:#b85237}.feedback h2{margin:3px 0;font:700 19px Georgia,"Songti SC",serif}.note-pills{display:flex;gap:5px;margin-top:8px}.note-pills span{border-radius:999px;background:white;padding:4px 7px;color:#52645d;font-size:9px}.next-button{border:0;border-radius:11px;background:var(--ink);color:white;padding:11px 14px;font-weight:800;white-space:nowrap;cursor:pointer}.next-button span{margin-left:8px;color:#a9c8bc}.learning-strip{max-width:calc(1380px - clamp(40px,10vw,152px));margin:18px auto 0;border-radius:18px;padding:16px 20px;display:grid;grid-template-columns:210px repeat(3,1fr);gap:20px;align-items:center}.learning-strip article{display:flex;gap:10px;align-items:flex-start}.learning-strip article+article{border-left:1px solid #e8e3d8;padding-left:20px}.learning-strip b{font-size:11px}.learning-strip article p{margin:4px 0 0;color:var(--muted);font-size:9px;line-height:1.5}.swatch{flex:none;width:9px;height:34px;border-radius:5px;background:var(--gold)}.swatch.minor{background:var(--jade)}.swatch.tense{background:var(--coral)}
@media(max-width:920px){.intro{align-items:flex-start;flex-direction:column;gap:14px}.training-layout{grid-template-columns:1fr}.settings-card{display:grid;grid-template-columns:auto 1fr auto;gap:18px;align-items:center}.settings-card fieldset{display:flex;gap:7px;margin:0}.level-option{margin:0}.level-option>span{min-width:125px}.sound-mode{margin:0;padding:0;border:0}.shortcut-note{display:none}.learning-strip{grid-template-columns:1fr 1fr}.learning-strip>.section-label{grid-column:1/3}.learning-strip article+article{border:0;padding-left:0}}@media(max-width:650px){.topbar{height:auto;min-height:72px;padding:12px 18px}.session-stats>span{min-width:0;padding:5px 8px}.session-stats>span:last-child{display:none}.brand small{display:none}.intro{padding:26px 18px 18px}.intro-copy{display:none}.training-layout{padding:0 18px}.settings-card{display:block}.settings-card fieldset{display:grid}.sound-mode{margin-top:15px;padding-top:15px;border-top:1px solid #e8e3d8}.answer-grid{grid-template-columns:1fr 1fr}.feedback{grid-template-columns:34px 1fr}.next-button{grid-column:1/3;width:100%}.learning-strip{margin:15px 18px 0;max-width:none;grid-template-columns:1fr}.learning-strip>.section-label{grid-column:auto}.listening-stage{min-height:245px}}@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important}.sound-rings i{animation:none!important}.answer-button,.play-button{transition:none}}
.direction-mode{margin-top:16px;padding-top:16px;border-top:1px solid #e8e3d8;display:flex;align-items:center;justify-content:space-between}.direction-mode b,.direction-mode small{display:block}.direction-mode b{font-size:11px}.direction-mode small{margin-top:4px;color:var(--muted);font-size:10px}.answer-grid.many-options{grid-template-columns:repeat(5,minmax(0,1fr));gap:6px;padding:10px 14px 14px}.answer-grid.many-options .answer-button{min-height:48px;padding:9px 8px}.answer-grid.many-options .answer-button strong{padding-right:18px;font-size:13px;white-space:nowrap}.answer-grid.many-options .answer-button small{display:none}
@media(max-width:800px){.answer-grid.many-options{grid-template-columns:repeat(4,minmax(0,1fr))}}@media(max-width:650px){.answer-grid.many-options{grid-template-columns:repeat(3,minmax(0,1fr));gap:5px;padding:8px}.answer-grid.many-options .answer-button{min-height:44px;padding:8px 6px}.answer-grid.many-options .answer-button strong{font-size:12px}.direction-mode{margin-top:15px;padding-top:15px}}
.intro h1{font-size:clamp(28px,3.2vw,46px);line-height:1.04}
.training-layout{padding-top:28px}
.practice-card{align-self:start}.listening-stage{min-height:220px}.play-button{width:104px;height:104px}.sound-rings i{width:105px;height:105px}.sound-rings i:nth-child(2){width:165px;height:165px}.sound-rings i:nth-child(3){width:220px;height:220px}.listening-stage>p{margin-top:15px}
.settings-card{padding:20px}.setting-group>span{display:block;margin-bottom:7px;color:#6f7b77;font-size:10px;font-weight:800;letter-spacing:.08em}.setting-group+.setting-group{margin-top:18px;padding-top:18px;border-top:1px solid #e8e3d8}.choice-row{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:6px}.choice-row button{width:100%;min-width:0;min-height:50px;padding:9px 10px;border:1px solid #d8d4ca;border-radius:11px;background:#fff;color:#63706c;text-align:left;font-size:11px;font-weight:800;line-height:1.2;cursor:pointer;transform:translateZ(0);transition:transform .16s ease,background-color .2s ease,border-color .2s ease,color .2s ease,box-shadow .2s ease}.choice-row button small{display:block;margin-top:3px;color:#919a96;font-size:8px;font-weight:500;line-height:1.35}.choice-row button.active{border-color:#236b62;background:#edf7f3;color:#236b62;box-shadow:inset 3px 0 #236b62;animation:option-select .24s ease-out}.compact-options{grid-template-columns:repeat(3,minmax(0,1fr))}.compact-options button{min-height:48px;padding:8px 5px;text-align:center}.shortcut-note{margin-top:18px}.play-button{position:relative;z-index:2}
@media(hover:hover){.choice-row button:hover{transform:translateY(-1px)}}.choice-row button:active{transform:scale(.975);transition-duration:.07s}@keyframes option-select{0%{transform:scale(.975)}65%{transform:scale(1.012)}100%{transform:scale(1)}}
@media(max-width:920px){.settings-card{display:block}.settings-card .choice-row{display:grid;grid-template-columns:repeat(2,minmax(0,1fr))}.settings-card .compact-options{grid-template-columns:repeat(3,minmax(0,1fr))}.shortcut-note{display:grid}}
@media(max-width:650px){.training-layout{padding:14px 10px 0}.settings-card{padding:16px;border-radius:18px}.setting-group+.setting-group{margin-top:14px;padding-top:14px}.choice-row button{min-height:48px;padding:8px 9px}.compact-options button{padding:8px 5px}.shortcut-note{display:none}.listening-stage{min-height:205px}.play-button{width:96px;height:96px}.sound-rings i:nth-child(3){width:200px;height:200px}}
@media(prefers-reduced-motion:reduce){.choice-row button{animation:none!important;transition:none!important;transform:none!important}}
@media(min-width:921px){.setting-group+.setting-group{margin-top:20px;padding-top:20px}.choice-row button{min-height:56px;padding:11px 10px}.compact-options button{min-height:52px;padding:9px 5px}.shortcut-note{padding:14px 12px;margin-top:20px}}
.practice-card.answered .answer-grid{display:flex;align-items:stretch;gap:8px;padding:9px 14px}.practice-card.answered .answer-button{display:none;flex:0 1 210px;min-height:44px;padding:8px 10px}.practice-card.answered .answer-button.correct,.practice-card.answered .answer-button.wrong{display:block}.practice-card.answered .answer-button strong{font-size:13px}.practice-card.answered .answer-button small{display:block;margin-top:2px;font-size:8px}.practice-card.answered .feedback{margin:0 14px 14px;padding:11px 12px;grid-template-columns:30px 1fr auto;gap:10px}.practice-card.answered .feedback-icon{width:30px;height:30px}.practice-card.answered .feedback h2{font-size:16px}.practice-card.answered .note-pills{margin-top:5px}.practice-card.answered .note-pills span{padding:3px 6px}.practice-card.answered .next-button{padding:9px 12px}
@media(max-width:650px){.practice-card.answered .answer-grid{padding:8px}.practice-card.answered .answer-button{flex:1 1 0;min-width:0}.practice-card.answered .feedback{grid-template-columns:28px 1fr;margin:0 8px 8px;padding:10px}.practice-card.answered .next-button{grid-column:1/3}}
@media(min-width:921px){.training-layout{grid-template-columns:300px minmax(0,1fr);align-items:start}.settings-card,.practice-card{height:600px}.settings-card{display:flex;flex-direction:column}.settings-card .shortcut-note{margin-top:auto}.practice-card{display:flex;flex-direction:column}.practice-card .listening-stage{flex:1;min-height:200px}.practice-card .answer-grid,.practice-card .feedback,.practice-card .round-result{flex:none}}
@media(max-width:920px){.settings-card,.practice-card{height:auto}.practice-card{display:block}.practice-card .listening-stage{min-height:220px}}