@font-face{font-family:"Space Grotesk";src:url("/learn-static/font-regular.ttf") format("truetype");font-weight:400;font-style:normal;font-display:swap}
@font-face{font-family:"Space Grotesk";src:url("/learn-static/font-bold.ttf") format("truetype");font-weight:600 800;font-style:normal;font-display:swap}
:root{--ink:#142b40;--ink-soft:#385267;--muted:#657b89;--line:#dce6e8;--paper:#fff;--canvas:#f3f7f6;--teal:#087e79;--teal-dark:#075e5a;--teal-wash:#e4f3f1;--amber:#a65e19;--amber-wash:#fff3e4;--red:#a43636;--red-wash:#fff0ed;--bluewash:#edf4f8;--shadow:0 10px 30px rgba(20,43,64,.07);--radius:14px;--font:"Space Grotesk",sans-serif;--mono:ui-monospace,SFMono-Regular,Consolas,monospace}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--canvas);color:var(--ink);font:400 15px/1.55 var(--font);-webkit-font-smoothing:antialiased}button,input,select,textarea{font:inherit;color:inherit}button{cursor:pointer}a{color:var(--teal-dark);text-underline-offset:3px}a:hover{color:var(--ink)}:focus-visible{outline:3px solid #d37736;outline-offset:3px;border-radius:4px}::selection{background:#c5e6df;color:var(--ink)}
.skip-link{position:absolute;left:-10000px;top:auto}.skip-link:focus{left:16px;top:12px;background:var(--paper);padding:12px;z-index:100}
.site-head{height:72px;background:var(--paper);border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;padding:0 clamp(16px,4vw,48px);gap:20px}.brand{display:flex;align-items:center;gap:12px;text-decoration:none;color:var(--ink);font-weight:700;font-size:18px}.brand img{width:38px;height:38px;object-fit:contain}.brand small{display:block;font-size:11px;line-height:1.2;color:var(--muted);font-weight:400;letter-spacing:.04em}.head-nav{display:flex;gap:24px;align-items:center}.head-nav a{text-decoration:none;color:var(--ink-soft);font-size:14px}.head-meta{color:var(--muted);font-size:13px}.site-footer{border-top:1px solid var(--line);padding:24px clamp(16px,4vw,48px);color:var(--muted);font-size:13px;display:flex;justify-content:space-between;gap:12px;margin-top:56px}
.wrap{max-width:1240px;margin:auto;padding:36px clamp(16px,4vw,44px) 64px}.narrow{max-width:740px}.reader-shell{max-width:1130px;margin:auto;padding:30px 24px 72px}.eyebrow{font-size:11px;text-transform:uppercase;letter-spacing:.13em;font-weight:700;color:var(--teal-dark)}h1,h2,h3,h4{font-weight:700;line-height:1.18;color:var(--ink);margin-top:0}h1{font-size:clamp(32px,4vw,48px);letter-spacing:-.035em}h2{font-size:26px;letter-spacing:-.02em}h3{font-size:18px}.lead{font-size:18px;color:var(--ink-soft);max-width:680px}.muted{color:var(--muted)}.small{font-size:12px}.rule{height:1px;background:var(--line);border:0;margin:24px 0}
.btn{min-height:42px;border:1px solid #c8d7d9;background:var(--paper);padding:9px 14px;border-radius:9px;color:var(--ink);display:inline-flex;align-items:center;justify-content:center;gap:8px;text-decoration:none;font-weight:600;font-size:13px;transition:transform .16s,background-color .16s,border-color .16s}.btn:hover{background:#f5faf9;border-color:#9ebcb9;transform:translateY(-1px)}.btn-primary{background:var(--teal);border-color:var(--teal);color:white}.btn-primary:hover{background:var(--teal-dark);border-color:var(--teal-dark);color:white}.btn-danger{color:var(--red);border-color:#e7bbbb}.btn-quiet{background:transparent;border-color:transparent}.btn-sm{min-height:34px;padding:6px 10px;font-size:12px}.btn[disabled]{opacity:.5;cursor:not-allowed;transform:none}.field{display:grid;gap:6px}.field label,.field-label{font-size:12px;font-weight:700;color:var(--ink-soft)}.input,.select,.textarea{width:100%;border:1px solid #c8d7d9;background:#fff;border-radius:8px;padding:10px 12px;min-height:42px}.textarea{min-height:110px;resize:vertical}.input:focus,.select:focus,.textarea:focus{border-color:var(--teal);outline:2px solid #b3ded8}.form-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}.span-2{grid-column:1/-1}.form-actions{display:flex;align-items:center;gap:10px;flex-wrap:wrap}.notice{border:1px solid #d2e0e2;background:#f8fbfa;border-radius:10px;padding:13px 15px;color:var(--ink-soft)}.notice.warn{background:var(--amber-wash);border-color:#efcfab;color:#744716}.notice.error{background:var(--red-wash);border-color:#ecc4be;color:#792e2e}.notice.success{background:var(--teal-wash);border-color:#b8ddd7;color:#165550}.status{display:inline-flex;padding:4px 9px;border-radius:999px;background:#eaf1f3;color:#385267;font-size:11px;font-weight:700;white-space:nowrap}.status.published,.status.approved{background:#e0f2ee;color:#145c53}.status.in_review,.status.scheduled{background:#fff0dd;color:#754714}.status.changes_requested,.status.archived{background:#f4e9e8;color:#813a38}
.card{background:var(--paper);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow)}.card-pad{padding:22px}.section-head{display:flex;align-items:flex-end;justify-content:space-between;gap:18px;margin-bottom:20px}.section-head h2{margin:4px 0}.toolbar{display:flex;gap:8px;align-items:center;flex-wrap:wrap}.stat-grid{display:grid;grid-template-columns:repeat(5,minmax(130px,1fr));gap:12px;margin:24px 0}.stat{padding:16px 17px;background:var(--paper);border:1px solid var(--line);border-radius:12px;min-height:105px}.stat strong{font-size:27px;display:block;letter-spacing:-.04em}.stat span{display:block;font-size:12px;color:var(--muted);margin-top:4px}.stat.issue strong{color:var(--amber)}.two-col{display:grid;grid-template-columns:minmax(0,1.6fr) minmax(280px,.8fr);gap:20px}.table-wrap{overflow:auto;border:1px solid var(--line);border-radius:10px;background:var(--paper)}table{border-collapse:collapse;width:100%;font-size:13px}th{text-align:left;color:var(--muted);font-size:11px;text-transform:uppercase;letter-spacing:.06em;background:#f7faf9;white-space:nowrap}th,td{padding:12px 13px;border-bottom:1px solid var(--line);vertical-align:middle}tr:last-child td{border-bottom:0}td a{font-weight:600}.article-title-cell{min-width:220px}.filterbar{display:grid;grid-template-columns:2fr repeat(4,minmax(130px,1fr));gap:9px;margin:18px 0}.pagination{display:flex;justify-content:space-between;align-items:center;gap:10px;padding:13px 2px;color:var(--muted);font-size:13px}.empty{padding:34px;text-align:center;color:var(--muted)}.empty strong{display:block;color:var(--ink);font-size:16px;margin-bottom:5px}
.login-layout{min-height:calc(100dvh - 72px);display:grid;place-items:center;padding:24px;background:radial-gradient(ellipse at 50% 20%,#e2f2ef 0%,var(--canvas) 60%)}.login-card{width:min(100%,460px);padding:34px}.login-card h1{font-size:30px;margin:12px 0}.login-card form{display:grid;gap:16px;margin-top:22px}
.admin-top{background:#fff;display:flex;align-items:center;justify-content:space-between;gap:16px;padding:14px clamp(16px,3vw,36px);border-bottom:1px solid var(--line)}.admin-main{max-width:1440px;margin:auto;padding:26px clamp(16px,3vw,36px) 72px}.workspace-grid{display:grid;grid-template-columns:minmax(0,1fr) 270px;gap:20px}.side-panel{display:grid;gap:14px;align-content:start}.data-list{list-style:none;margin:0;padding:0}.data-list li{padding:12px 0;border-bottom:1px solid var(--line)}.data-list li:last-child{border-bottom:0}
.editor-title-row{display:flex;align-items:flex-start;justify-content:space-between;gap:16px}.editor-layout{display:grid;grid-template-columns:minmax(0,1fr) 320px;gap:18px;margin-top:20px;align-items:start}.editor-main{min-width:0}.editor-meta{display:grid;gap:14px}.tabs{display:flex;gap:4px;border-bottom:1px solid var(--line);margin-bottom:12px}.tab{border:0;background:none;padding:10px 13px;color:var(--muted);border-bottom:2px solid transparent;font-weight:600}.tab[aria-selected="true"]{color:var(--teal-dark);border-color:var(--teal)}.editor-toolbar{display:flex;gap:5px;flex-wrap:wrap;border:1px solid var(--line);border-radius:9px 9px 0 0;background:#f7faf9;padding:8px}.editor-toolbar button{min-width:36px;padding:6px;border:1px solid transparent;background:transparent;border-radius:6px;font-size:12px}.editor-toolbar button:hover{background:#e7f1ef;border-color:#ccdfdc}.editor-canvas,.source-area{width:100%;min-height:560px;padding:25px clamp(18px,4vw,54px);border:1px solid var(--line);background:white;border-radius:0 0 10px 10px;font-size:17px;line-height:1.75;outline:none}.editor-canvas:focus{box-shadow:inset 0 0 0 2px #b6dfd9}.source-area{font:14px/1.65 var(--mono);resize:vertical}.save-state{font-size:12px;color:var(--muted)}.editor-canvas h1,.editor-canvas h2,.editor-canvas h3{margin:1.5em 0 .5em}.editor-canvas p{margin:.8em 0}.recovery-banner{margin:12px 0}.preview-box{border:1px solid var(--line);border-radius:10px;background:#f9fbfa;padding:16px;overflow:auto}.preview-box.mobile{max-width:390px;margin:auto}
.comment{padding:13px 0;border-bottom:1px solid var(--line)}.comment:last-child{border-bottom:0}.comment-head{display:flex;justify-content:space-between;gap:10px}.issue-row{padding:10px 0;border-bottom:1px solid var(--line);font-size:13px}.issue-row:last-child{border:0}.issue-row.error{color:var(--red)}.issue-row.warning{color:var(--amber)}.source-row,.event-row{padding:12px 0;border-bottom:1px solid var(--line);overflow-wrap:anywhere}.source-row:last-child,.event-row:last-child{border:0}.diff{white-space:pre-wrap;font:13px/1.6 var(--mono);padding:14px;border-radius:8px;background:#f4f7f7;max-height:350px;overflow:auto}.diff-add{color:#135a4c;background:#e4f4ee}.diff-del{color:#923c37;background:#fff0ed}
.media-upload{border-top:1px solid var(--line);margin-top:16px;padding-top:14px}.media-upload h4{margin:0 0 6px}.media-form{display:grid;gap:10px;margin-top:12px}.media-confirm{display:flex;align-items:flex-start;gap:9px;font-size:12px;color:var(--ink-soft)}.media-confirm input{width:18px;height:18px;margin:0;accent-color:var(--teal)}.is-refreshing{position:relative}.is-refreshing::after{content:"Updating editorial record…";position:absolute;inset:0;z-index:5;display:grid;place-items:center;background:rgba(243,247,246,.72);color:var(--ink);font-weight:700;border-radius:12px;pointer-events:none}
.library-hero{background:#eaf5f3;border-bottom:1px solid #d6e8e5;padding:48px 24px 38px}.library-inner{max-width:1180px;margin:auto}.library-hero h1{max-width:700px;margin:10px 0}.search-form{display:flex;gap:8px;max-width:760px;margin:24px 0 18px}.search-form .input{min-height:52px;font-size:16px}.subject-nav{display:flex;gap:8px;flex-wrap:wrap}.subject-nav a{padding:7px 12px;border:1px solid #c6dcda;border-radius:999px;text-decoration:none;font-size:12px;background:#fff}.library-content{max-width:1180px;margin:auto;padding:30px 24px}.library-grid{display:grid;grid-template-columns:240px minmax(0,1fr);gap:26px}.filter-panel{padding:18px;align-self:start}.filter-panel .field{margin-bottom:15px}.book-list{display:grid;gap:12px}.book-card{padding:19px 21px}.book-card h2{font-size:20px;margin:6px 0}.book-card h2 a{text-decoration:none;color:var(--ink)}.book-card p{margin:0;color:var(--ink-soft);max-width:720px}.book-meta{display:flex;gap:10px;flex-wrap:wrap;font-size:12px;color:var(--muted);margin-top:12px}.reader-topline{display:flex;align-items:center;justify-content:space-between;margin-bottom:26px}.breadcrumbs{display:flex;gap:8px;align-items:center;flex-wrap:wrap;font-size:13px;color:var(--muted)}.breadcrumbs a{text-decoration:none}.reader-layout{display:grid;grid-template-columns:220px minmax(0,740px) 1fr;gap:28px;align-items:start}.toc{position:sticky;top:20px;border-left:2px solid var(--line);padding-left:14px;font-size:13px}.toc h2{font-size:12px;text-transform:uppercase;letter-spacing:.08em;color:var(--muted)}.toc a{display:block;text-decoration:none;color:var(--ink-soft);padding:5px 0}.toc a.level-3{padding-left:12px}.article{font-size:18.5px;line-height:1.75;min-width:0}.article h1{font-size:clamp(34px,5vw,50px);margin:12px 0 16px}.article h2{font-size:30px;margin:2.2em 0 .6em}.article h3{font-size:22px;margin:1.7em 0 .5em}.article p{margin:1.05em 0}.article blockquote{margin:1.5em 0;border-left:3px solid var(--teal);padding:4px 18px;color:var(--ink-soft)}.article pre{overflow:auto;padding:16px;background:#142b40;color:#edf5f4;border-radius:8px;font:14px/1.6 var(--mono)}.article code{font-family:var(--mono);font-size:.88em;background:#eef3f3;padding:.12em .3em;border-radius:4px}.article pre code{background:none;padding:0}.article table{display:block;overflow-x:auto;max-width:100%;border:1px solid var(--line);border-radius:8px}.article th,.article td{min-width:120px}.article img{max-width:100%;height:auto;border-radius:8px}.article figure{margin:1.7em 0}.article figcaption{color:var(--muted);font-size:14px}.article .math{overflow-x:auto}.author-box{border-top:1px solid var(--line);margin-top:38px;padding-top:22px;display:flex;gap:16px}.author-box img{width:62px;height:62px;object-fit:cover;border-radius:50%}.author-box p{font-size:14px;margin:6px 0}.related-list a{display:block;padding:11px 0;border-bottom:1px solid var(--line);text-decoration:none;font-weight:600}.reader-cta{background:var(--teal-wash);padding:20px;border-radius:12px;margin:36px 0}
.dialog-backdrop{position:fixed;inset:0;background:rgba(14,35,49,.42);z-index:20;display:grid;place-items:center;padding:16px}.dialog{width:min(100%,540px);max-height:90dvh;overflow:auto;background:#fff;border-radius:14px;padding:24px;box-shadow:0 20px 80px rgba(15,39,54,.24)}.dialog h2{margin:0 0 10px}.dialog-actions{display:flex;justify-content:flex-end;gap:8px;flex-wrap:wrap;margin-top:18px}.toast{position:fixed;bottom:18px;right:18px;z-index:30;max-width:min(400px,calc(100vw - 36px));padding:13px 16px;background:var(--ink);color:#fff;border-radius:9px;box-shadow:var(--shadow)}.toast.error{background:#792e2e}.loading-line{height:12px;border-radius:99px;background:#e7efef;animation:pulse 1.2s ease-in-out infinite}.skeleton{display:grid;gap:12px}.sr-only{position:absolute!important;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
@keyframes pulse{50%{opacity:.45}}
@media(max-width:980px){.stat-grid{grid-template-columns:repeat(3,1fr)}.reader-layout{grid-template-columns:180px minmax(0,740px)}.reader-aside{display:none}.editor-layout{grid-template-columns:minmax(0,1fr) 280px}.filterbar{grid-template-columns:repeat(3,1fr)}}
@media(max-width:740px){.site-head{height:62px}.head-nav{gap:12px}.head-nav a:not(.btn){display:none}.wrap{padding-top:24px}.stat-grid{grid-template-columns:repeat(2,1fr)}.two-col,.workspace-grid,.editor-layout{grid-template-columns:1fr}.workspace-grid .side-panel{grid-template-columns:1fr 1fr}.editor-meta{grid-template-columns:repeat(2,minmax(0,1fr))}.editor-meta>*{min-width:0}.filterbar{grid-template-columns:1fr 1fr}.library-grid{grid-template-columns:1fr}.filter-panel{display:grid;grid-template-columns:repeat(2,1fr);gap:10px}.filter-panel .field{margin:0}.reader-layout{display:block}.toc{position:static;margin-bottom:22px;border-left:0;border-top:1px solid var(--line);padding:14px 0 0}.toc[hidden]{display:none}.article{font-size:18px}.reader-shell{padding:22px 18px 48px}.search-form{flex-direction:column}.site-footer{margin-top:30px}.editor-canvas,.source-area{min-height:420px}.editor-meta{grid-template-columns:1fr 1fr}}
@media(max-width:480px){.brand{font-size:16px}.head-meta{display:none}.admin-top{align-items:flex-start;flex-direction:column}.admin-top .toolbar{width:100%}.stat-grid{gap:8px}.stat{min-height:88px;padding:12px}.stat strong{font-size:22px}.filterbar,.filter-panel{grid-template-columns:1fr}.editor-title-row{display:block}.editor-title-row .toolbar{margin-top:12px}.editor-meta{grid-template-columns:1fr}.workspace-grid .side-panel{grid-template-columns:1fr}.form-grid{grid-template-columns:1fr}.span-2{grid-column:auto}.reader-topline{align-items:flex-start}.article h2{font-size:26px}.site-footer{flex-direction:column}}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{scroll-behavior:auto!important;animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important}}
.article-byline{margin:-7px 0 12px!important;font-size:14px;line-height:1.35}.article-byline a{display:inline-flex;align-items:baseline;gap:8px;text-decoration:none;font-weight:700}.article-byline-role{color:var(--muted);font-size:13px;font-weight:400}.author-box{align-items:center;border:1px solid var(--line);border-radius:14px;background:#f8fbfa;padding:20px;margin-top:40px;gap:20px}.author-box img{width:112px;height:112px;flex:0 0 112px;border-radius:10px}.author-box-copy{min-width:0}.author-box h2{font-size:21px;margin:4px 0 0}.author-box h2 a{color:var(--ink);text-decoration:none}.author-box .author-role{font-size:14px;color:var(--muted);margin:3px 0 8px}.author-box p{font-size:14px;line-height:1.6;margin:7px 0}.author-more{font-size:13px;font-weight:700;text-decoration:none}.author-page{max-width:1020px;margin:0 auto;padding:30px 24px 72px}.author-page-top{display:flex;align-items:center;justify-content:space-between;gap:18px;margin-bottom:28px}.author-preview-note{margin-bottom:24px}.author-profile{display:grid;grid-template-columns:minmax(230px,340px) minmax(0,1fr);gap:clamp(28px,6vw,68px);align-items:start;padding:clamp(24px,5vw,52px);border:1px solid var(--line);border-radius:18px;background:var(--paper);box-shadow:var(--shadow)}.author-profile-portrait{overflow:hidden;border-radius:12px;background:var(--teal-wash);aspect-ratio:4/5}.author-profile-portrait img{display:block;width:100%;height:100%;object-fit:cover}.author-profile h1{margin:10px 0 7px;font-size:clamp(34px,5vw,48px)}.author-profile-role{font-size:17px;color:var(--teal-dark);font-weight:600;margin:0 0 26px}.author-bio{font-size:17px;line-height:1.75;color:var(--ink-soft)}.author-bio p{margin:0 0 1.2em}.author-library-link{margin-top:12px}
@media(max-width:740px){.author-page{padding:22px 18px 48px}.author-profile{grid-template-columns:1fr;gap:24px;padding:22px}.author-profile-portrait{width:min(100%,340px);aspect-ratio:5/4}.author-profile-portrait img{object-position:center 35%}.author-profile-role{margin-bottom:18px}.author-bio{font-size:16px}.author-box{align-items:flex-start;padding:16px;gap:14px}.author-box img{width:82px;height:82px;flex-basis:82px}}
@media(max-width:420px){.article-byline a{align-items:flex-start;flex-direction:column;gap:2px}.author-box{flex-direction:column}.author-box img{width:92px;height:92px;flex-basis:92px}.author-profile-portrait{width:100%}.author-page-top{align-items:flex-start}}