:root{color-scheme:light;--bg:#f4f5f1;--paper:#fffefa;--ink:#172c29;--muted:#687974;--line:#e1e6de;--line-strong:#d3dcd3;--forest:#17483c;--forest-deep:#12382f;--accent:#d8ae76;--pale:#e8efe9;--warm:#f8eee0;--red:#9d453c;--red-bg:#faeae7;--green:#24684c;--green-bg:#e7f2ea;--shadow:0 18px 50px rgba(23,57,47,.055);--rad:18px;font-family:Inter,-apple-system,BlinkMacSystemFont,"Segoe UI",Arial,sans-serif;font-synthesis:none}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--bg);color:var(--ink);line-height:1.52}button,select{font:inherit}button{cursor:pointer}a{text-decoration:none;color:inherit}button:focus-visible,a:focus-visible,select:focus-visible{outline:3px solid #bb985d;outline-offset:3px}::selection{background:#d6ead7} .site{display:flex;min-height:100vh}
.sidebar{background:#102d26;color:#e8f1e9;width:262px;flex:0 0 262px;position:sticky;top:0;align-self:flex-start;height:100vh;padding:30px 17px 20px;display:flex;flex-direction:column;overflow:auto;z-index:4}.brand{display:flex;align-items:center;gap:12px;padding:4px 9px;margin-bottom:60px}.brand-mark{width:44px;height:44px;display:grid;place-items:center;position:relative;background:#f3f6ed;border-radius:13px;color:#17483c;font-family:Georgia,serif;font-size:30px;font-weight:bold}.brand-mark i{width:9px;height:9px;position:absolute;background:#d39e66;border-radius:50%;bottom:7px;right:5px}.brand-copy strong{display:block;font-family:Georgia,serif;font-size:30px;letter-spacing:-1.8px;line-height:1}.brand-dot,.mobile-logo span{color:#d5a471}.brand-copy small{font-size:9px;letter-spacing:1.5px;color:#aabfb3;font-weight:800}.menu-label{color:#78998b;font-size:10px;font-weight:850;letter-spacing:2.2px;padding:0 15px;margin-bottom:13px}.nav{display:grid;gap:5px}.nav-item{border:0;background:none;color:#b6cbbf;display:flex;align-items:center;text-align:left;gap:13px;padding:13px 14px;border-radius:11px;width:100%;font-weight:640;font-size:13px}.nav-item:hover{background:#1e4036;color:#fff}.nav-item.active{color:#fff;background:#285044}.nav-item .ni{width:22px;text-align:center;font-size:21px;line-height:1}.nav-counter{margin-left:auto;border-radius:10px;background:#305247;color:#d9eadb;min-width:23px;text-align:center;padding:1px 6px;font-size:11px}.sidebar-bottom{margin-top:auto;padding:20px 5px 0}.mini-tip{border:1px solid #355248;border-radius:14px;padding:17px 14px;background:linear-gradient(140deg,#1b4135,#1b372e);display:grid;gap:4px;font-size:12px;color:#a8c3b5}.mini-tip strong{color:#f7f7ef;font-size:13px}.mini-spark{color:#ddb881;font-size:25px;line-height:1;margin-bottom:6px}.pdf-link{display:flex;align-items:center;gap:12px;margin:18px 2px 16px;padding:10px 7px;color:#dfede4;font-size:12px}.pdf-link>span:last-child{margin-left:auto}.pdf-link:hover{color:#ebcaa4}.side-credit{border-top:1px solid #2f5043;padding:14px 7px 0;color:#799989;font-size:10px}.page-frame{min-width:0;flex:1;display:flex;flex-direction:column}.topbar{height:82px;display:flex;align-items:center;justify-content:space-between;padding:0 clamp(24px,5%,76px);border-bottom:1px solid var(--line);background:color-mix(in srgb,var(--paper) 65%,var(--bg));gap:12px}.top-left,.top-right{display:flex;gap:18px;align-items:center}.breadcrumb{font-size:13px;color:var(--muted);font-weight:650}.mobile-logo{display:none;font-family:Georgia,serif;font-size:27px;font-weight:700}.saved-pill{font-size:11px;color:var(--muted);border:1px solid var(--line);border-radius:30px;padding:7px 11px;display:flex;align-items:center;gap:7px;white-space:nowrap}.saved-circle{width:7px;height:7px;background:#73a986;border-radius:50%}.icon-btn{height:36px;min-width:36px;padding:0 10px;border:1px solid var(--line);background:var(--paper);border-radius:10px;color:var(--ink);font-weight:700}.icon-btn:hover{border-color:#aac4b6}.focus-btn{font-size:13px}.focus-btn[aria-pressed="true"]{background:var(--forest);color:#fff}main{width:min(1180px,100%);margin:0 auto;flex:1;padding:clamp(24px,4vw,54px) clamp(20px,5%,72px) 55px}.footer{border-top:1px solid var(--line);padding:20px clamp(20px,5%,72px) 24px;color:var(--muted);font-size:11px;display:flex;justify-content:space-between;gap:15px}.mobile-nav{display:none} .eyebrow{display:flex;align-items:center;gap:8px;text-transform:uppercase;letter-spacing:2px;color:#608274;font-size:10px;font-weight:850}.eyebrow::before{content:"";width:15px;height:2px;background:#c59660}.title-xl{font-family:Georgia,'Times New Roman',serif;font-weight:600;font-size:clamp(37px,4.5vw,60px);line-height:1.09;letter-spacing:-2px;margin:12px 0 14px}.title-lg{font-family:Georgia,serif;font-size:clamp(31px,3.3vw,44px);letter-spacing:-1px;font-weight:600;line-height:1.15;margin:9px 0 13px}.lead{color:var(--muted);font-size:15px;max-width:650px;margin:0}.section-head{display:flex;align-items:end;justify-content:space-between;gap:18px;margin:35px 0 19px}.section-head h2{font-family:Georgia,serif;font-weight:600;font-size:25px;margin:0;letter-spacing:-.4px}.section-head p{color:var(--muted);font-size:12px;margin:4px 0 0}.chip{font-size:11px;border-radius:30px;padding:6px 10px;background:var(--pale);color:var(--forest);font-weight:760;white-space:nowrap}.muted{color:var(--muted)}.small{font-size:12px}.divider{height:1px;background:var(--line);margin:18px 0}.btn{border:1px solid transparent;display:inline-flex;justify-content:center;align-items:center;gap:10px;border-radius:12px;padding:12px 18px;font-size:13px;font-weight:760;transition:transform .17s,background 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32px;position:relative;overflow:hidden}.hero-main::after{content:"";width:380px;height:380px;border:1px solid rgba(240,232,201,.1);border-radius:50%;position:absolute;right:-95px;top:-160px;box-shadow:0 0 0 47px rgba(240,232,201,.025),0 0 0 94px rgba(240,232,201,.02);pointer-events:none}.hero-main h1{font-size:clamp(37px,3.8vw,56px);font-family:Georgia,serif;font-weight:600;line-height:1.08;letter-spacing:-1.4px;margin:20px 0 15px;max-width:520px;position:relative;z-index:1}.hero-main p{color:#b7d3c3;font-size:13px;max-width:400px;position:relative;z-index:1}.hero-main .btn{background:#f5f4e9;color:#164234;margin-top:16px;position:relative;z-index:1}.hero-tag{color:#edd1a0;font-size:10px;letter-spacing:2.1px;font-weight:850;text-transform:uppercase}.hero-aside{display:flex;flex-direction:column;justify-content:space-between;min-height:326px;padding:27px}.hero-aside 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span{font-size:11px;color:var(--muted)}.stat-top{display:flex;align-items:center;justify-content:space-between;color:#6e8a7c;font-size:18px}.stat-label{font-size:12px;font-weight:700;margin-top:6px}.actions-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}.action-tile{padding:25px 21px;display:flex;flex-direction:column;min-height:222px}.action-icon{height:40px;width:40px;border-radius:12px;background:var(--pale);display:grid;place-items:center;color:var(--forest);font-size:24px}.action-tile h3{font-size:16px;margin:17px 0 6px}.action-tile p{font-size:12px;color:var(--muted);margin:0 0 15px}.action-tile .ghost{margin-top:auto;align-self:start}.callout{background:#f3eee4;border:1px solid #e8dfd1;border-radius:15px;padding:19px 23px;display:flex;align-items:start;gap:16px;font-size:12px;color:#665947}.callout strong{color:#3c4e3e;font-size:13px}.callout .callout-icon{font-size:27px;color:#9b8056;line-height:1.1}.callout p{margin:4px 0 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h2{font-family:Georgia,serif;font-size:30px;font-weight:600;margin:0 0 17px}.lesson-article .lesson-summary{font-size:17px;line-height:1.73;color:var(--ink)}.point-list{display:grid;gap:12px;padding:0;list-style:none;margin:22px 0 28px}.point-list li{display:flex;gap:12px;background:var(--bg);border-radius:12px;padding:15px;font-size:13px}.point-list li::before{content:"✓";color:var(--green);font-weight:900}.takeaway{padding:22px;background:var(--pale);border-radius:14px;border-left:3px solid #87ad91}.takeaway small{display:block;color:var(--green);font-size:10px;font-weight:850;letter-spacing:1.4px;margin-bottom:6px}.lesson-bottom{margin-top:22px;display:flex;justify-content:space-between;gap:12px;flex-wrap:wrap}.source{color:var(--muted);font-size:11px}.toolbar{display:flex;align-items:end;justify-content:space-between;gap:14px;flex-wrap:wrap;margin:26px 0 19px}.filters{display:flex;gap:12px;align-items:end;flex-wrap:wrap}.field{display:grid;gap:6px}.field label{color:var(--muted);font-size:11px;font-weight:750}select{min-width:128px;appearance:none;border:1px solid var(--line-strong);border-radius:10px;background:var(--paper);color:var(--ink);font-weight:600;padding:11px 34px 11px 12px;cursor:pointer;background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16'%3E%3Cpath d='m4 6 4 4 4-4' fill='none' stroke='%236b8275' stroke-width='1.5'/%3E%3C/svg%3E");background-size:15px;background-repeat:no-repeat;background-position:right 10px center;font-size:12px}.filter-switch{display:flex;align-items:center;gap:8px;font-size:12px;cursor:pointer}.filter-switch input{accent-color:var(--forest);width:16px;height:16px}.card-area{max-width:720px;margin:0 auto}.study-meta{display:flex;align-items:center;justify-content:space-between;color:var(--muted);font-size:12px;margin:25px 0 13px}.flashcard{min-height:322px;border:1px solid var(--line-strong);border-radius:22px;background:var(--paper);box-shadow:var(--shadow);width:100%;text-align:left;padding:33px 40px;position:relative;display:flex;flex-direction:column;justify-content:space-between;color:var(--ink);transition:background .15s,transform .2s}.flashcard:hover{transform:translateY(-2px);border-color:#aac1b3}.flashcard.is-flipped{background:var(--pale)}.card-top{display:flex;justify-content:space-between;align-items:center;gap:12px;color:#4c806a;font-size:11px;font-weight:800}.flashcard h2{font-family:Georgia,serif;font-size:clamp(24px,3.2vw,37px);line-height:1.24;font-weight:600;letter-spacing:-.7px;margin:27px 0}.flashcard .flip-help{display:flex;justify-content:space-between;gap:10px;align-items:center;color:var(--muted);font-size:12px}.flashcard .source{margin-top:8px}.card-actions{display:flex;gap:12px;justify-content:center;margin-top:18px}.card-actions .btn{flex:1}.card-nav{margin-top:20px;display:flex;justify-content:space-between;gap:10px;align-items:center}.review-note{margin-top:17px;color:var(--muted);font-size:11px;text-align:center}.empty{border:1px dashed var(--line-strong);padding:46px 25px;border-radius:17px;text-align:center;background:var(--paper)}.empty .icon{font-size:36px}.empty h3{font-family:Georgia,serif;font-size:25px;font-weight:600}.empty p{font-size:13px;color:var(--muted);max-width:420px;margin:0 auto 20px}.setup-grid{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,.9fr);gap:20px;align-items:start;margin-top:28px}.config{padding:27px}.config h3{font-family:Georgia,serif;font-size:24px;font-weight:600;margin:0 0 20px}.config-fields{display:grid;gap:19px}.segmented{display:flex;gap:7px;padding:4px;background:var(--bg);border-radius:12px}.segmented button{background:transparent;border:0;border-radius:9px;padding:11px 8px;color:var(--muted);font-size:12px;font-weight:760;flex:1}.segmented button.active{background:var(--paper);box-shadow:0 2px 9px rgba(16,40,31,.09);color:var(--forest)}.config select{width:100%}.config .btn{margin-top:24px}.config-help{padding:28px;background:var(--pale);border-radius:17px}.config-help h3{font-family:Georgia,serif;font-size:25px;margin:8px 0 11px}.config-help p,.config-help li{font-size:12px;color:#547064;line-height:1.8}.config-help ul{padding-left:20px}.question-panel{max-width:820px;margin:0 auto}.question-head{display:flex;justify-content:space-between;gap:12px;align-items:center;margin-bottom:14px}.question-box{padding:clamp(24px,4vw,42px)}.question-box h2{font-family:Georgia,serif;font-size:clamp(25px,3vw,33px);font-weight:600;line-height:1.35;margin:17px 0 26px}.option-list{display:grid;gap:11px}.option{width:100%;text-align:left;border:1px solid var(--line-strong);border-radius:12px;padding:15px;display:flex;align-items:center;gap:13px;background:var(--paper);font-size:13px;line-height:1.55;color:var(--ink)}.option .letter{border:1px solid var(--line-strong);border-radius:9px;width:31px;height:31px;display:grid;place-items:center;flex:none;font-size:12px;font-weight:830}.option:not(:disabled):hover{border-color:#86a995;background:var(--pale)}.option.selected{border-color:#3b8064;background:var(--pale)}.option.correct{border-color:#75aa85;background:var(--green-bg)}.option.incorrect{border-color:#e7a69d;background:var(--red-bg)}.option:disabled{cursor:default}.explain{background:var(--pale);border-radius:14px;padding:19px 21px;font-size:13px;color:#3b5b4d;margin-top:23px}.explain h3{margin:0 0 6px;font-size:13px}.explain p{margin:0 0 10px}.explain.wrong{background:var(--red-bg);color:#81433b}.question-actions{display:flex;justify-content:space-between;align-items:center;margin-top:21px;gap:10px}.result-hero{padding:40px;text-align:center}.result-hero .score{font-family:Georgia,serif;font-size:88px;line-height:1;margin:16px 0}.result-hero h2{font-family:Georgia,serif;font-size:31px;font-weight:600;margin:10px 0}.result-hero p{color:var(--muted);font-size:13px;max-width:460px;margin:0 auto 22px}.result-hero .buttons{display:flex;justify-content:center;gap:10px;flex-wrap:wrap}.result-list{display:grid;gap:10px;margin-top:18px}.result-item{padding:18px 20px}.result-item summary{cursor:pointer;display:flex;gap:12px;font-size:13px;font-weight:680}.result-item summary .status{width:22px;flex:0 0 22px;color:var(--green)}.result-item.bad summary .status{color:var(--red)}.result-item .answer-block{font-size:12px;color:var(--muted);padding:13px 0 0 33px}.answer-block p{margin:5px 0}.answer-block strong{color:var(--ink)}.review-grid{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin-top:27px}.review-panel{padding:25px}.review-panel h3{font-family:Georgia,serif;font-size:24px;font-weight:600;margin:0 0 7px}.review-panel p{font-size:12px;color:var(--muted);margin:0 0 19px}.review-panel .giant{font-family:Georgia,serif;font-size:55px;line-height:1.2}.mistake-list{display:grid;gap:11px;margin-top:19px}.mistake{padding:17px 19px;display:flex;gap:13px;align-items:start}.mistake .num{font-family:Georgia,serif;color:var(--red);font-size:20px}.mistake strong{font-size:13px}.mistake p{color:var(--muted);font-size:11px;margin:5px 0 0}.mistake .chip{margin-left:auto}.confusions{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px}.confusion{padding:20px 22px}.confusion h3{font-size:14px;margin:0 0 7px}.confusion p{font-size:12px;color:var(--muted);margin:0}.toast{position:fixed;bottom:28px;left:50%;transform:translate(-50%,100px);opacity:0;pointer-events:none;z-index:11;background:#173e33;color:#fff;padding:11px 18px;border-radius:12px;font-size:12px;box-shadow:0 13px 32px rgba(0,0,0,.16);transition:transform .24s,opacity .24s}.toast.show{transform:translate(-50%,0);opacity:1}.mobile-note{display:none}
body.dark{color-scheme:dark;--bg:#0c1a17;--paper:#142721;--ink:#eef4ee;--muted:#9bad9f;--line:#274239;--line-strong:#3e5a4e;--forest:#569d79;--forest-deep:#448763;--pale:#203d30;--warm:#382b22;--red:#f2a99a;--red-bg:#422522;--green:#9bdbb7;--green-bg:#244632;--shadow:0 18px 40px rgba(0,0,0,.14)}body.dark .sidebar{background:#07120f}body.dark .hero-main{background:#1b4a3d}body.dark .btn.primary{color:#071b13}body.dark .callout{background:#312b22;border-color:#49402d;color:#d9c6a6}body.dark .callout strong{color:#f1e8d9}body.dark .option.correct{color:var(--ink)}body.dark .option.incorrect{color:var(--ink)}body.dark .config-help p,body.dark .config-help li{color:#b3cabc}body.dark .explain{color:#c8e1d2}body.dark .explain.wrong{color:#f5c8bc}body.dark .flashcard.is-flipped{background:#1c3a2b}body.dark select{color-scheme:dark}body.dark .hero-main .btn{color:#164234}
body.focus .sidebar{display:none}body.focus .page-frame{max-width:1000px;margin:auto;width:100%}body.focus .stats,body.focus .actions-grid{display:none}body.focus .footer{display:none}body.focus .hero{grid-template-columns:1fr}body.focus .hero-aside{display:none}
@media(max-width:1120px){.sidebar{width:238px;flex-basis:238px}.hero{grid-template-columns:1.3fr .7fr}.hero-aside{padding:22px}.stat{padding:15px}.action-tile{padding:20px}}
@media(max-width:900px){.sidebar{width:212px;flex-basis:212px}.brand{margin-bottom:38px}.brand-copy strong{font-size:26px}.nav-item{font-size:12px;padding:12px 10px}.hero{grid-template-columns:1fr}.hero-main{min-height:300px}.hero-aside{min-height:180px}.big-number{font-size:49px}.actions-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.setup-grid{grid-template-columns:1fr}}
@media(max-width:680px){.sidebar{display:none}.topbar{height:60px;padding:0 19px}.breadcrumb{display:none}.mobile-logo{display:inline}.saved-pill{display:none}.top-right{gap:7px}.focus-btn span{display:none}main{padding:25px 17px 98px}.footer{display:none}.mobile-nav{display:grid;position:fixed;bottom:0;left:0;right:0;z-index:8;grid-template-columns:repeat(5,1fr);background:var(--paper);border-top:1px solid var(--line);padding:7px 5px calc(8px + env(safe-area-inset-bottom));box-shadow:0 -6px 20px rgba(0,0,0,.03)}.mobile-nav button{display:grid;gap:2px;justify-items:center;border:0;background:none;color:var(--muted);font-size:22px;padding:4px 2px}.mobile-nav button.active{color:var(--forest)}.mobile-nav small{font-size:9px;font-weight:760}.hero-main{padding:29px 26px;min-height:280px}.hero-main h1{font-size:41px}.hero-aside{min-height:150px}.stats{grid-template-columns:repeat(3,minmax(0,1fr));gap:8px}.stat{padding:13px 10px}.stat .n{font-size:27px}.stat .stat-label{font-size:10px}.actions-grid{grid-template-columns:1fr 1fr;gap:10px}.action-tile{padding:19px 16px;min-height:190px}.action-tile h3{font-size:14px}.action-tile p{font-size:11px}.section-head h2{font-size:23px}.lesson-grid,.review-grid,.confusions{grid-template-columns:1fr}.lesson-item{min-height:180px}.lesson-article{padding:24px}.lesson-article .lesson-summary{font-size:15px}.flashcard{min-height:330px;padding:25px 23px}.flashcard h2{font-size:29px}.card-actions{gap:7px}.card-actions .btn{padding:11px 8px;font-size:11px}.toolbar{gap:12px}.filters{width:100%}.field{flex:1}.field select{width:100%}.question-box{padding:22px 18px}.option{padding:12px}.question-actions .btn{padding:10px 13px}.result-hero{padding:27px 19px}.result-hero .score{font-size:70px}.panel{padding:20px}.toast{bottom:83px;white-space:nowrap;max-width:90vw;text-align:center}.mobile-note{display:block;font-size:11px;color:var(--muted);text-align:center;margin-top:13px}}
@media(max-width:375px){.hero-main h1{font-size:34px}.stat .n{font-size:23px}.flashcard h2{font-size:25px}.card-actions{flex-wrap:wrap}.card-actions .btn{flex:1 0 40%}}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{transition:none!important;scroll-behavior:auto!important;animation:none!important}}