*{box-sizing:border-box}body{margin:0;background:#f9f6ed;color:#173f42;font-family:"PingFang TC","Heiti TC",system-ui,sans-serif}a{color:#205d52}button,select{font-family:inherit}.site-header{position:sticky;top:0;z-index:50;display:flex;align-items:center;gap:18px;flex-wrap:wrap;padding:18px max(24px,calc((100vw - 1112px)/2));background:#fffdf7ed;border-bottom:1px solid #d9dfd0;backdrop-filter:blur(12px)}.brand{font-size:21px;font-weight:800;text-decoration:none;margin-right:auto;white-space:nowrap}.brand span{display:block;font-size:12px;letter-spacing:.06em;font-weight:500;margin-top:4px}.book-selector{display:grid;gap:4px;font-size:12px}.book-selector select{font-size:18px;padding:8px 30px 8px 12px;min-height:44px;border:1px solid #77958a;border-radius:8px;background:#fffdf8;color:#173f42}.grade-label{font-size:14px;white-space:nowrap}.pptx-top-button{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:46px;padding:11px 16px;border:1px solid #987333;border-radius:9px;background:#f4d48b;color:#3a3f26;text-decoration:none;font-size:15px;font-weight:700;white-space:nowrap}.pptx-top-button[aria-disabled=true]{opacity:.5;pointer-events:none}.difficulty-controls{display:flex;gap:9px;flex-wrap:wrap;margin:10px 0}.difficulty-button{padding:10px 16px;min-height:44px;border:2px solid transparent;border-radius:99px;font:inherit;font-weight:700;cursor:pointer;color:#233c35}.difficulty-button.all{background:#e4e9e3}.difficulty-button.easy{background:#d6eedf;color:#174c30}.difficulty-button.intermediate{background:#ffe7b0;color:#68491e}.difficulty-button.advanced{background:#e9ddf5;color:#5b3975}.difficulty-button[aria-pressed=true]{border-color:currentColor}.difficulty-button[aria-pressed=true]::before{content:'✓ ';font-weight:800}button:focus-visible,a:focus-visible,select:focus-visible{outline:3px solid #995317;outline-offset:3px}.filter-count{font-size:14px;color:#567168;margin:8px 0}.level-tag{display:inline-block;font-size:12px;padding:4px 9px;border-radius:99px;background:#e5eadf;margin-left:8px}.empty-state{margin:auto;max-width:650px;text-align:center;line-height:1.8}.library-link{max-width:1064px;margin:30px auto 60px;border-top:1px solid #cdd9cd;padding:24px 0;line-height:1.8}.library-link h2{font-size:21px}.library-link a{font-weight:700}footer{padding:25px;text-align:center;border-top:1px solid #d9dfd0;font-size:13px;color:#587269}.teach-source p{overflow-wrap:anywhere}.teach-slide{scroll-margin-top:145px}.teach-stage.is-presenting .teach-slide{overflow:auto}.teach-actions .navigation{flex-wrap:wrap}.picture-only .teach-source,.picture-only .photo-note{visibility:hidden}@media(max-width:700px){.site-header{padding:12px 16px;gap:10px}.brand{width:100%;font-size:19px}.brand span{display:inline;margin-left:10px;font-size:11px}.grade-label{margin-right:auto;font-size:12px}.pptx-top-button{padding:10px;font-size:13px}.book-selector select{font-size:16px;max-width:105px}.difficulty-button{font-size:13px;padding:9px 12px}.library-link{margin:25px 16px 40px}.teaching-intro{padding-top:25px}.teach-stage.is-presenting .slide-content{grid-template-columns:1fr}.teach-stage.is-presenting .slide-image{max-height:38dvh}.teach-stage.is-presenting .slide-text h2{font-size:32px}.teach-stage.is-presenting .teach-actions{gap:7px}.teach-stage.is-presenting .teach-actions .navigation{gap:6px}}@media print{.site-header,.difficulty-controls,.filter-count,.library-link,footer{display:none}}

[hidden]{display:none!important}.content-views{display:flex;gap:10px;flex-wrap:wrap;margin:16px 0}.content-views button{background:#fffdf7;color:#24574e;border:1px solid #83a295;border-radius:9px;padding:12px 18px;font:inherit;font-weight:700;cursor:pointer}.content-views button[aria-pressed=true]{background:#24574e;color:#fff}.library-explanation{line-height:1.8;border-left:4px solid #7b9e80;padding:8px 16px}.library-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px}.library-card{background:#fffdf7;border:1px solid #d4ddce;border-radius:12px;padding:20px;line-height:1.65;min-width:0}.library-card h3{font-size:28px;margin:12px 0 4px}.library-card p{margin:6px 0}.library-card .py,.library-card .zy{color:#39665c}.library-card .en{color:#52685d}.library-card summary{cursor:pointer;color:#24574e;font-weight:700;margin-top:12px}.library-card .teach-button{margin-top:15px;font-size:14px}.selected-label{display:inline-block;font-size:12px;background:#f4d48b;border-radius:99px;padding:3px 8px;margin-left:5px}.full-library.hide-py .py,.full-library.hide-zy .zy,.full-library.hide-en .en{display:none}.library-example .meaning-zh{font-size:19px}.picture-only .full-library h3,.picture-only .full-library p{visibility:visible}@media(max-width:650px){.library-grid{grid-template-columns:1fr}.content-views button{padding:11px 13px;font-size:14px}}

.typeset-art{display:block;position:relative;container-type:inline-size;justify-self:center;width:100%;max-width:410px;max-height:none}.typeset-art>img{display:block;width:100%;height:auto;max-height:none}.art-text{position:absolute;display:block;line-height:1.3;font-family:"Heiti TC","Noto Sans TC",sans-serif;white-space:normal;overflow:hidden}.picture-choice .typeset-art{align-self:center}.picture-choice .typeset-art img{height:auto}.teach-stage:is(:fullscreen,.is-presenting) .typeset-art{max-width:60vh}@media(max-width:700px){.typeset-art{max-width:260px}}

.quiz-context .meaning-zh{font-size:24px;line-height:1.5;margin:0 0 8px}.quiz-context .py,.quiz-context .zy,.quiz-context .en{font-size:16px;line-height:1.5;margin:4px 0}.quiz-context{border-bottom:1px solid #d8decb;padding-bottom:10px}