:root{--ink:#182b26;--green:#257659;--muted:#79817b;--line:#e2e6df;--paper:#f6f7f2}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:100px}body{margin:0;background:#fff;color:var(--ink);font:15px/1.65 -apple-system,BlinkMacSystemFont,"PingFang SC","Microsoft YaHei",sans-serif}a{color:inherit;text-decoration:none}button,input{font:inherit}button,a,input{outline-offset:5px}button{cursor:pointer}button:hover,.text-link:hover{filter:brightness(.93)}[hidden]{display:none!important}.top{height:82px;border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;padding:0 4.5%;gap:24px;background:white;position:sticky;top:0;z-index:10}.brand{font-size:23px;letter-spacing:1px;font-weight:700;display:flex;align-items:center;gap:12px;white-space:nowrap}.brand small{font-size:15px;font-weight:400;color:#737b76;border-left:1px solid var(--line);padding-left:12px}.logo{font-size:19px;color:white;background:#db7d48;width:36px;height:36px;display:grid;place-items:center;border-radius:10px}.top nav{display:flex;height:100%;gap:38px;align-items:center}.top nav a{height:100%;display:flex;align-items:center;font-size:14px;color:#6d756f;border-bottom:3px solid transparent}.top nav .active{color:var(--green);border-bottom-color:var(--green);font-weight:650}.preview{font-size:11px;background:#f3f4ef;border:1px solid var(--line);padding:4px 10px;border-radius:4px;white-space:nowrap}.hero{max-width:1360px;margin:auto;padding:65px 4.5% 54px;display:grid;grid-template-columns:1fr 1.08fr;gap:58px;align-items:center}.eyebrow{font-size:10px;font-weight:650;letter-spacing:2.3px;color:var(--green);margin:0 0 24px}.hero h1{font-size:clamp(38px,4.3vw,64px);line-height:1.25;letter-spacing:-2px;font-weight:650;margin:0 0 24px}.hero h1 span{color:var(--green)}.intro{font-size:15px;line-height:1.95;color:#727a72}.hero-actions{display:flex;gap:23px;align-items:center;margin:29px 0 35px}.primary{background:var(--green);color:white;border:0;border-radius:5px;padding:13px 20px;font-weight:550;font-size:14px}.primary span{padding-left:20px}.text-link{font-size:13px}.hero-meta{display:flex;gap:13px;color:#838a82;font-size:11px}.hero-meta span+span{border-left:1px solid #d9ddd5;padding-left:13px}.visual{background:#eff1e9;padding:19px;border-radius:9px}.visual-label{display:flex;justify-content:space-between;font-size:11px;margin:0 0 14px;color:#677363}.visual-label span+span{font-size:9px;letter-spacing:1px}.visual-grid{display:grid;grid-template-columns:1.18fr 1fr;grid-template-rows:228px 122px;gap:12px}figure{margin:0;position:relative;overflow:hidden;border-radius:5px;background:#e2e5dd}figure img{width:100%;height:100%;object-fit:cover;display:block}figcaption{position:absolute;bottom:0;left:0;padding:18px 12px 9px;width:100%;background:linear-gradient(transparent,#0007);color:white;font-size:10px}.v-main{grid-row:span 2}.v-bottom img{object-position:center}.path{max-width:1238px;margin:0 auto 66px;border-top:1px solid var(--line);border-bottom:1px solid var(--line);padding:25px 0;display:flex;align-items:center;justify-content:space-between;gap:20px}.path small{display:block;color:var(--muted);font-size:10px;margin-bottom:4px}.path strong{font-size:15px;font-weight:550}.path p{display:flex;align-items:center;gap:25px;font-size:13px}.path b{color:#a3b0a0;font-weight:400}.catalog{max-width:1238px;margin:0 auto 75px;scroll-margin-top:90px}.section-head{display:flex;align-items:center;justify-content:space-between;gap:24px}.section-head .eyebrow{margin-bottom:10px}h2{font-size:26px;letter-spacing:-.6px;font-weight:600;margin:0}.search{border:1px solid var(--line);border-radius:5px;display:flex;gap:10px;align-items:center;padding:9px 14px;color:#7b847b;width:270px}.search input{border:0;outline:0;min-width:0;width:100%;font-size:12px;background:transparent}.filters{display:flex;gap:8px;margin:29px 0 20px;flex-wrap:wrap}.filters button{border:1px solid transparent;background:#f6f7f3;padding:8px 14px;font-size:12px;border-radius:4px;color:#6d776c}.filters button.selected{background:var(--ink);color:white}.catalog-heading{display:flex;justify-content:space-between;font-size:11px;color:#8b9288;border-bottom:1px solid var(--line);padding-bottom:15px;margin-bottom:24px}.cards{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:29px 22px}.card{display:block;min-width:0}.card figure{height:166px;background:#eef1e9;border:1px solid #e6e9e2;border-radius:5px}.card img{transition:transform .25s}.card:hover img{transform:scale(1.035)}.card .tag{font-size:10px;color:var(--green);margin:15px 0 7px;display:flex;justify-content:space-between}.card .tag span+span{color:#959b91}.card h3{font-size:16px;line-height:1.55;font-weight:550;margin:0 0 8px}.card .caption{font-size:11px;color:#8b9387;margin:0}.placeholder{height:100%;display:flex;flex-direction:column;justify-content:center;padding:25px;color:#375b44;background:#eaf0e3}.placeholder b{font-size:30px;font-weight:400}.placeholder span{font-size:12px;margin-top:8px}footer{border-top:1px solid var(--line);padding:28px 4.5%;font-size:12px;display:flex;justify-content:space-between;color:#8a9187;gap:20px}footer span{font-size:10px}#reader{display:grid;grid-template-columns:265px minmax(0,1fr);max-width:1550px;margin:auto}.sidebar{height:calc(100vh - 82px);position:sticky;top:82px;overflow-y:auto;background:#f8f9f5;border-right:1px solid var(--line);padding:28px 20px}.back{font-size:12px;color:var(--muted)}.sidebar h2{font-size:18px;margin:26px 0 3px}.sidebar>p{font-size:12px;color:var(--muted)}details{border-top:1px solid var(--line);padding:12px 0}summary{cursor:pointer;font-size:13px;font-weight:550}details a{display:block;font-size:11px;padding:9px 10px;line-height:1.7;color:#6d796d;margin-top:3px;border-radius:4px}details a.current{background:#e6efe5;color:#1c694c}.reading{padding:32px 45px;min-width:0}.crumb{font-size:11px;color:#8b9289;margin-bottom:36px}.reading h1{font-size:32px;line-height:1.4;margin:0 0 14px}.reading .eyebrow{margin-bottom:14px}.lesson-meta{font-size:11px;color:#8b9387;border-bottom:1px solid var(--line);padding-bottom:25px;display:flex;gap:14px}.reading-layout{display:grid;grid-template-columns:minmax(0,1fr) 150px;gap:38px;margin-top:20px}article{min-width:0;color:#404a40;line-height:1.9;font-size:14px}article h2{font-size:23px;margin:30px 0 16px}article h3{font-size:20px;color:var(--ink);margin:26px 0 16px}article img{max-width:100%;height:auto;display:block;border-radius:5px;margin:22px auto}article a{color:var(--green);text-decoration:underline;overflow-wrap:anywhere}article pre{position:relative;padding:48px 20px 20px;background:#f4f6f0;border:1px solid #e0e6dc;border-radius:6px;white-space:pre-wrap;overflow-wrap:anywhere;font:12px/1.9 ui-monospace,monospace;max-height:430px;overflow:auto}article blockquote{margin:20px 0;padding:10px 20px;background:#f5f7ef;border-left:3px solid #8da481}article table{display:block;overflow:auto;border-collapse:collapse}article td,article th{padding:8px;border:1px solid #ddd}.copy{position:absolute;right:10px;top:10px;border:1px solid #d9e0d3;background:white;color:var(--green);font-size:11px;border-radius:3px;padding:5px 9px}.outline{position:sticky;top:110px;align-self:start;font-size:11px;margin-top:20px}.outline a{display:block;padding:10px 0;color:#7b8777;border-bottom:1px solid var(--line)}.outline p{margin-top:30px;color:#949c90;font-size:10px}.reader-actions{display:flex;justify-content:space-between;border-top:1px solid var(--line);padding:25px 0;margin-top:30px;font-size:12px}#toast{position:fixed;bottom:25px;left:50%;transform:translateX(-50%);background:var(--ink);color:white;font-size:12px;border-radius:5px;padding:10px 18px;display:none;z-index:40}@media(min-width:1500px){.hero{padding-left:0;padding-right:0;max-width:1238px}}@media(max-width:1330px){.path,.catalog{margin-left:4.5%;margin-right:4.5%}}@media(max-width:1000px){.top nav{gap:18px}.hero{gap:24px;padding-top:40px}.hero h1{font-size:44px}.hero-meta{flex-wrap:wrap}.hero-actions{align-items:flex-start;flex-direction:column;gap:15px}.visual-grid{grid-template-rows:200px 110px}.path p{gap:15px}.cards{grid-template-columns:repeat(3,minmax(0,1fr))}.reading{padding:28px}.reading-layout{grid-template-columns:1fr}.outline{display:none}#reader{grid-template-columns:230px minmax(0,1fr)}}@media(max-width:700px){.top{height:auto;min-height:104px;flex-wrap:wrap;padding:13px 5% 0;gap:8px}.brand{font-size:18px}.logo{width:30px;height:30px;font-size:16px}.top nav{order:3;width:100%;height:43px;gap:23px;overflow-x:auto;white-space:nowrap}.top nav a{font-size:12px}.preview{margin-left:auto}.hero{grid-template-columns:1fr;padding:34px 5% 28px;gap:27px}.hero h1{font-size:43px}.hero .eyebrow{font-size:9px;margin-bottom:18px}.hero-actions{flex-direction:row;align-items:center;gap:18px;margin-bottom:23px}.primary{font-size:12px;padding:12px 15px}.primary span{padding-left:10px}.text-link{font-size:11px}.hero-meta{font-size:10px}.visual-grid{grid-template-rows:182px 104px}.path{display:block;margin-bottom:36px;padding:20px 0}.path p{justify-content:space-between;gap:6px;font-size:11px;margin-top:18px}.section-head{display:block}h2{font-size:23px}.search{width:100%;margin-top:20px}.filters{gap:6px;margin-top:18px}.filters button{font-size:11px;padding:7px 10px}.cards{grid-template-columns:repeat(2,minmax(0,1fr));gap:24px 14px}.card figure{height:130px}.card h3{font-size:14px}.card .tag{font-size:9px}.catalog-heading>span+span{display:none}.catalog{margin-bottom:40px}footer{display:block;font-size:11px}footer span{display:block;margin-top:10px}#reader{display:block}.sidebar{position:static;height:auto;border-bottom:1px solid var(--line);padding:17px 5%}.sidebar h2,.sidebar>p{display:none}#lesson-nav{display:none}.reading{padding:25px 5%}.reading h1{font-size:25px}.crumb{margin-bottom:25px}.reading-layout{display:block}.reading .eyebrow{font-size:9px}article{font-size:14px}article pre{font-size:11px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{transition:none!important}}

/* Course reading: imported callouts and long external URLs */
.reading-layout{min-width:0}.reading-layout article{min-width:0;overflow-wrap:anywhere;word-break:normal}.reading-layout .outline{min-width:0;overflow-wrap:anywhere}.reading-layout .outline a{line-height:1.45}.lesson-callout{background:#f7f9f5;border:1px solid #e3e9e0;border-left:3px solid #7ca48d;border-radius:5px;padding:22px 24px;margin:18px 0 22px;position:relative}.lesson-callout:before{content:attr(data-emoji);display:block;font-size:21px;margin-bottom:5px}.lesson-callout p{margin:0 0 10px}.lesson-callout p:first-of-type strong{font-size:17px;color:var(--ink)}.lesson-callout ul{list-style:none;padding:0;margin:14px 0 0;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}.lesson-callout li{background:#fff;border:1px solid #e8ebe5;padding:11px 13px;border-radius:4px;font-size:13px;line-height:1.55;overflow-wrap:anywhere}.lesson-callout li a{display:inline-block;font-size:12px}.lesson-callout li strong{color:#243a2d}@media(max-width:1180px){.reading-layout{grid-template-columns:minmax(0,1fr)}.reading-layout .outline{display:none}}@media(max-width:700px){.lesson-callout{padding:18px}.lesson-callout ul{grid-template-columns:1fr}.lesson-callout li{font-size:12px}}

.tool-directory .reading-layout{display:block}.tool-directory .reading-layout article{max-width:1020px}.tool-directory .outline{display:none}.lesson-callout p:first-of-type strong{display:block;margin-bottom:3px}.lesson-callout li p{margin:0}.lesson-callout li a{margin-left:6px;white-space:nowrap}

article video{display:block;width:100%;max-width:900px;height:auto;margin:22px auto;border-radius:5px;background:#161e1c}article img[alt]{max-width:100%}.card .caption{min-height:18px}

.empty-note{padding:25px;border:1px solid var(--line);background:#f7f9f5;border-radius:4px;color:#647166}