@import url('https://fonts.googleapis.com/css2?family=Be+Vietnam+Pro:wght@400;450;500;550;600;650;700;750&family=Lora:wght@400;500;600&display=swap');
:root{--bg:#f6f7f2;--paper:#fff;--ink:#243a30;--muted:#69746b;--green:#244e40;--light:#eaf0e7;--line:#dde3da;--red:#a44037;--gold:#806327;--radius:14px}*{box-sizing:border-box}body{margin:0;color:var(--ink);background:var(--bg);font:14px/1.65 'Be Vietnam Pro',sans-serif}button,input,select{font:inherit}button,a,input,select{ -webkit-tap-highlight-color:transparent}button{cursor:pointer}button:disabled{cursor:default;opacity:.45}button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible{outline:3px solid #9b7131;outline-offset:4px}::selection{background:#d5e4c4;color:#203c2d}::-webkit-scrollbar{width:8px;height:8px}::-webkit-scrollbar-thumb{background:#bdcbbb;border-radius:6px}svg{width:20px;height:20px;fill:none;stroke:currentColor;stroke-width:1.7;stroke-linecap:round;stroke-linejoin:round;flex-shrink:0}.topbar{height:86px;background:#fff;border-bottom:1px solid var(--line);padding:0 42px;display:flex;align-items:center;gap:25px}.brand{display:flex;align-items:center;gap:18px;color:var(--ink);text-decoration:none;font-weight:600;font-size:15px}.brand-symbol{font-family:'Lora',serif;font-size:30px;font-weight:600;letter-spacing:-2px}.brand-symbol span{color:#8d9a66}.source-label{margin-left:auto;font-size:12px;color:var(--muted)}.file-tag{background:var(--bg);padding:6px 10px;margin-left:8px;border-radius:5px;color:var(--ink)}.quiet{border:0;background:none;color:var(--muted);padding:8px 10px;min-height:40px}.quiet:hover{color:var(--green);background:var(--light);border-radius:6px}#help-toggle span{display:inline-grid;place-items:center;border:1px solid #9aa497;border-radius:50%;width:18px;height:18px;margin-left:5px;font-size:11px}.help{background:#eaf0e7;padding:20px 42px;border-bottom:1px solid var(--line);color:var(--green)}.workspace{display:grid;grid-template-columns:258px minmax(0,1fr);max-width:1600px;margin:auto}.sidebar{padding:37px 24px;border-right:1px solid var(--line);min-height:calc(100vh - 86px)}.sidebar-heading{display:flex;align-items:center;justify-content:space-between;padding:0 10px;margin-bottom:20px}.sidebar h2{font-size:13px;margin:0;font-weight:600}.small{font-size:10px;letter-spacing:.1em;color:#78836e}.nav-item{display:flex;justify-content:space-between;align-items:center;width:100%;text-align:left;padding:13px 12px;border:0;background:none;color:var(--muted);border-radius:8px;margin-bottom:4px;font-size:12px}.nav-item.active{background:var(--light);color:var(--green);font-weight:600}.nav-item:hover{background:#edf1e9}.count{font-variant-numeric:tabular-nums;font-size:11px;background:#e6eae2;border-radius:5px;padding:1px 7px}.nav-item.active .count{background:#d7e2d1}.sidebar-section{margin:31px 10px 0}.sidebar-section label,.sidebar h3{font-size:11px;color:var(--muted);font-weight:500;display:block;margin:0 0 11px}select{border:1px solid var(--line);background:#fff;width:100%;padding:10px 8px;border-radius:6px;color:var(--ink);font-size:11px}.progress-section{padding-top:27px;border-top:1px solid var(--line)}.progress-numbers{display:flex;align-items:baseline;gap:7px;font-size:10px;color:var(--muted)}.progress-numbers strong{font-size:30px;font-weight:500;color:var(--green);font-variant-numeric:tabular-nums}progress{width:100%;height:6px;display:block;margin-top:10px;appearance:none;border:0;border-radius:10px;overflow:hidden;background:#e0e6da}progress::-webkit-progress-bar{background:#e0e6da}progress::-webkit-progress-value{background:#6d8a59;border-radius:10px}progress::-moz-progress-bar{background:#6d8a59}.progress-section p{font-size:10px;color:var(--muted);margin-top:10px}.score-line{display:flex;justify-content:space-between;font-size:10px;margin-top:22px}.score-line strong{font-weight:600}.study-note{margin:50px 10px 0;padding:24px 0 0;border-top:1px solid var(--line)}.study-note svg{color:#7b8c62;width:30px;height:30px}.study-note p{font-family:Lora,serif;font-size:22px;line-height:1.5;margin:13px 0 10px}.study-note strong{font-weight:500}.study-note>span,.local-note{font-size:10px;color:var(--muted)}.local-note{margin:34px 10px 0}main{padding:39px 48px;min-width:0;max-width:1200px;width:100%;margin:auto}.page-heading{display:flex;align-items:center;justify-content:space-between;gap:18px;margin-bottom:30px}h1{font-family:Lora,serif;font-size:30px;line-height:1.35;font-weight:500;letter-spacing:-.03em;margin:0 0 10px;text-wrap:balance}.page-heading p{font-size:11px;color:var(--muted);margin:0}.button{border:1px solid var(--green);color:#fff;background:var(--green);padding:12px 20px;border-radius:7px;display:inline-flex;align-items:center;justify-content:center;gap:8px;font-size:12px;font-weight:500;min-height:44px}.button:hover{background:#32634f}.button.secondary{border-color:var(--line);background:white;color:var(--ink)}.button.secondary:hover{background:var(--light)}.button svg{width:16px;height:16px}.toolbar{display:flex;justify-content:space-between;align-items:center;border-bottom:1px solid var(--line);margin-bottom:24px}.tabs{display:flex;gap:25px}.tab{border:0;border-bottom:2px solid transparent;padding:0 0 13px;background:none;color:var(--muted);font-size:12px}.tab.active{color:var(--green);border-bottom-color:var(--green);font-weight:600}.toolbar>span{font-size:11px;color:var(--muted);padding-bottom:13px}.quiz{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:29px 32px 24px;min-height:468px}.question-meta{display:flex;align-items:center;justify-content:space-between;gap:12px;font-size:11px;color:var(--muted)}.question-meta strong{color:var(--green);font-weight:600;font-size:12px}.part-label{border-left:1px solid var(--line);margin-left:12px;padding-left:12px}.bookmark{display:flex;align-items:center;gap:7px;border:0;background:none;color:var(--muted);font-size:11px;min-height:36px}.bookmark[aria-pressed=true]{color:var(--gold)}.bookmark[aria-pressed=true] svg{fill:#f3e7c7}.question-title{font-size:21px;font-weight:550;line-height:1.6;letter-spacing:-.02em;margin:21px 0 23px;max-width:68ch}.options{display:grid;gap:10px}.option{background:#fff;border:1px solid var(--line);border-radius:8px;padding:13px 16px;display:flex;align-items:center;gap:14px;text-align:left;color:var(--ink);font-size:12px;line-height:1.65;width:100%;min-height:54px}.option:hover:not(:disabled){border-color:#8fa384;background:#f7faf4}.option:disabled{opacity:1;cursor:default}.option.selected{background:#f1f5ed;border-color:#6e8960}.letter{border:1px solid var(--line);border-radius:5px;display:grid;place-items:center;min-width:27px;height:28px;font-size:11px;color:var(--muted);background:#fbfcf9}.selected .letter{background:var(--green);border-color:var(--green);color:white}.option.correct{background:#eef5e8;border-color:#85a36f}.option.correct .letter{color:white;background:#4b7440;border-color:#4b7440}.option.incorrect{background:#fcf0ed;border-color:#d4978b}.option.incorrect .letter{color:#fff;background:var(--red);border-color:var(--red)}.answer-state{margin-left:auto;font-weight:600;font-size:10px;white-space:nowrap}.feedback{padding:16px 18px;border-radius:8px;margin-top:18px;background:#edf4e8;color:#35562d;font-size:12px}.feedback.wrong{background:#fcf0ed;color:#94392e}.feedback p{margin:5px 0 0}.source-warning{font-size:11px;line-height:1.7;background:#fbf5e5;color:#785d28;padding:12px 15px;border-radius:7px;margin-top:16px}.quiz-actions{border-top:1px solid var(--line);padding-top:20px;margin-top:24px;display:flex;align-items:center;justify-content:space-between;gap:10px}.quiz-actions .right{display:flex;gap:9px}.keyboard-tip{color:var(--muted);font-size:10px}.question-index{margin-top:32px}.index-heading{display:flex;justify-content:space-between;align-items:center;gap:18px}.index-heading h2{font-size:14px;font-weight:600;margin:0 0 4px}.index-heading p{font-size:10px;color:var(--muted);margin:0}.search{display:flex;align-items:center;gap:9px;background:#fff;border:1px solid var(--line);border-radius:7px;padding:8px 10px}.search svg{width:15px;height:15px;color:var(--muted)}.search input{min-width:0;width:180px;border:0;outline:none;color:var(--ink);font-size:10px;padding:3px;background:none}.legend{display:flex;gap:19px;margin:18px 0 13px;color:var(--muted);font-size:10px}.legend>span{display:flex;align-items:center;gap:6px}.dot{display:inline-block;width:7px;height:7px;border-radius:50%;background:#b6c0b0}.dot.green{background:#74975e}.dot.red{background:#c58072}.dot.marked{background:#c7a552}.question-grid{display:grid;grid-template-columns:repeat(15,minmax(0,1fr));gap:7px}.question-number{position:relative;border:1px solid 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var(--line);font-size:10px;color:var(--muted)}.text-button{border:0;background:none;color:var(--muted);font-size:10px;text-decoration:underline;text-underline-offset:3px;padding:10px}.toast{position:fixed;bottom:24px;left:50%;transform:translateX(-50%);background:var(--green);color:white;padding:12px 22px;border-radius:8px;font-size:12px;box-shadow:0 6px 25px #203e3026;z-index:10;max-width:90vw}.result{margin-top:20px;padding:22px;background:var(--light);border-radius:10px}.result h2{margin:0;font-family:Lora,serif;font-weight:500;font-size:24px}.result p{font-size:12px}.result .button{margin:5px 8px 0 0}.empty{padding:50px 0;text-align:center}.empty h2{font-size:22px}.empty p{color:var(--muted);font-size:13px}.empty .button{margin-top:16px}dialog{border:0;border-radius:14px;max-width:440px;width:calc(100% - 36px);padding:30px;background:#fff;color:var(--ink);box-shadow:0 15px 60px #203c2e33}dialog::backdrop{background:#20382d55}dialog h2{margin:0 0 12px;font-size:22px}dialog p{font-size:13px;color:var(--muted)}.dialog-actions{display:flex;gap:10px;margin-top:25px}.quiz{animation:arrive .3s cubic-bezier(.16,1,.3,1)}@keyframes arrive{from{transform:translateY(7px)}to{transform:translateY(0)}}[hidden]{display:none!important}@media(min-width:1450px){main{padding:44px 64px}}@media(max-width:1100px){.workspace{grid-template-columns:225px minmax(0,1fr)}main{padding:32px 28px}.sidebar{padding:30px 17px}.page-heading{align-items:flex-start}h1{font-size:26px}.page-heading .button{white-space:nowrap;font-size:10px;padding:10px}.question-grid{grid-template-columns:repeat(10,minmax(0,1fr))}.keyboard-tip{display:none}.quiz{padding:24px}.question-title{font-size:19px}.search input{width:140px}}@media(max-width:760px){.topbar{height:70px;padding:0 20px;gap:10px}.brand{gap:12px;font-size:13px}.brand-symbol{font-size:28px}.source-label{display:none}#help-toggle{margin-left:auto;font-size:11px}.workspace{display:block}.sidebar{padding:18px 20px;border-right:0;border-bottom:1px solid var(--line);min-height:auto}.sidebar-heading,.progress-section,.study-note,.local-note{display:none}.sidebar nav{display:flex;gap:5px}.nav-item{padding:10px 9px;font-size:10px;gap:6px;justify-content:center}.count{font-size:9px;padding:1px 5px}.sidebar-section{margin:12px 0 0;display:flex;align-items:center;gap:15px}.sidebar-section label{margin:0;white-space:nowrap;font-size:10px}.sidebar select{font-size:11px;width:auto;flex:1;padding:8px}main{padding:26px 20px}.page-heading{margin-bottom:25px;flex-wrap:wrap;gap:15px}h1{font-size:27px;max-width:350px}.page-heading p{font-size:10px;max-width:310px;line-height:1.8}.page-heading .button{font-size:11px;padding:9px 13px;min-height:39px}.tabs{gap:20px}.tab{font-size:11px}.toolbar>span{font-size:10px}.quiz{padding:18px 17px;min-height:440px}.question-title{font-size:18px;margin-top:18px}.question-meta strong{font-size:11px}.part-label{font-size:9px;margin-left:8px;padding-left:8px}.bookmark{font-size:0;gap:0}.bookmark svg{width:20px}.option{padding:12px;font-size:12px;gap:10px}.letter{min-width:25px;height:26px}.answer-state{font-size:0}.answer-state:after{content:'✓';font-size:15px}.incorrect .answer-state:after{content:'×'}.quiz-actions{flex-wrap:wrap}.quiz-actions .button{padding:10px 13px;font-size:11px}.index-heading{align-items:flex-start;flex-direction:column;gap:15px}.search{width:100%}.search input{width:100%;font-size:11px}.question-grid{gap:6px;grid-template-columns:repeat(8,minmax(0,1fr))}.question-number{min-height:38px;font-size:11px}.legend{gap:17px}.index-heading p{font-size:10px}footer{align-items:flex-start;gap:15px;font-size:9px}.help{padding:16px 20px;font-size:12px}}@media(prefers-reduced-motion:reduce){*{animation:none!important;scroll-behavior:auto!important}}
@media(max-width:760px){.sidebar .progress-section{display:none}}
.donate-dialog{max-width:440px;max-height:calc(100dvh - 32px);overflow-y:auto;padding:30px 26px 24px}.donate-dialog h2{font-family:Lora,serif;font-weight:500;padding-right:32px;line-height:1.4}.donate-dialog #donate-description{margin:0;line-height:1.7}.donate-close{position:absolute;top:14px;right:12px;width:44px;height:44px;display:grid;place-items:center}.donate-qr{margin:16px 0}.donate-qr img{display:block;width:min(100%,240px);height:auto;margin:0 auto}.donate-qr figcaption{text-align:center;font-size:11px;color:var(--muted);margin-top:6px}.donate-details{margin:20px 0 0;font-size:13px}.donate-details>div{display:flex;justify-content:space-between;gap:12px;padding:8px 0;border-bottom:1px solid var(--line)}.donate-details dt{color:var(--muted)}.donate-details dd{margin:0;font-weight:600;text-align:right}.donate-details #donate-account{font-variant-numeric:tabular-nums;user-select:all}.donate-dialog .dialog-actions{margin-top:12px;flex-wrap:wrap}.donate-dialog .dialog-actions .button{flex:1;white-space:nowrap}.donate-dialog .donate-status{min-height:22px;margin:12px 0 0;font-size:12px;color:var(--green)}