/* Visual system for the Applied Econometrics companion site. */
:root{
  --navy:#173c47;--navy-deep:#091e29;--blue:#356b77;
  --gold:#dea869;--gold-dark:#a96939;--ink:#203640;
  --muted:#62757a;--paper:#f8f7f3;--pale:#eaf1ef;--line:#dce5e3;
  --shadow:0 18px 48px rgba(14,43,51,.12)
}
body{background:var(--paper);color:var(--ink);font-size:15px}
:focus-visible{outline:3px solid var(--gold);outline-offset:3px}
.site-header{position:sticky;top:0;height:76px;background:rgba(9,30,41,.97);border-bottom:1px solid #ffffff25;backdrop-filter:blur(12px)}
.brand{color:#fff;font-size:20px}
.brand:hover{color:#fff}
.brand small{color:#dec7a9;font-size:9px}
.brand-symbol{background:#f5e9d7;color:var(--navy-deep);border-radius:7px}
.main-nav{gap:20px}
.main-nav a{color:#dce8e6;border-bottom-color:transparent;padding:2px 7px 0;font-size:14px}
.main-nav a:hover,.main-nav a.active{color:#fff;border-bottom-color:var(--gold)}
.menu-toggle{color:#fff}
.hero{
  color:#fff;
  background:linear-gradient(90deg,rgba(5,20,31,.94) 0%,rgba(5,20,31,.85) 35%,rgba(5,20,31,.25) 68%,rgba(5,20,31,.06) 100%),url('/art/hero-applied.webp') center center/cover no-repeat,var(--navy-deep)
}
.hero:before{display:none}
.hero:after{content:"";position:absolute;inset:75% 0 0;background:linear-gradient(transparent,rgba(5,19,27,.35));pointer-events:none}
.hero-grid{display:flex;min-height:650px;align-items:center;position:relative;z-index:1}
.hero-copy{max-width:670px;padding:70px 0 66px}
.eyebrow{letter-spacing:.11em;font-weight:800}
.hero .eyebrow{color:#f0cda7}
.hero .eyebrow:before,.eyebrow.navy:before{content:"";display:inline-block;width:28px;height:2px;background:#d18d66;vertical-align:middle;margin-right:10px}
.hero h1{font-size:clamp(45px,5vw,72px);line-height:1.19;margin:18px 0 20px;letter-spacing:.015em;color:#fff}
.hero-lead{font:500 clamp(19px,1.9vw,25px)/1.6 "Songti SC","STSong",serif;color:#eef3ed;margin:0 0 13px}
.hero-detail{color:#d2dfdf;font-size:16px;line-height:1.94;max-width:580px;margin:0}
.hero-actions{margin:31px 0 25px}
.button{border-radius:7px;gap:19px}
.button.gold{background:var(--gold);color:#102b33}
.button.gold:hover{background:#efbe82}
.button.outline-light{color:#fff;border-color:#d0dfdf88;background:#ffffff0b}
.button.outline-light:hover{background:#ffffff22}
.hero .byline{color:#d1dedc;letter-spacing:.04em}
.hero .byline span{color:var(--gold)}
.quickstats{background:#fff}
.stat-grid{padding:26px 0}
.stat-grid strong{color:var(--navy)}
.stat-grid span{font-size:13px}
.section{padding:clamp(62px,7vw,100px) 0}
.section h2{font-size:clamp(30px,3.5vw,45px);line-height:1.32;margin:11px 0 24px}
.section-head{display:flex;justify-content:space-between;align-items:end;gap:30px;margin-bottom:32px}
.section-head h2{margin-bottom:0}
.section-head p{margin:0;max-width:390px;color:var(--muted);font-size:15px;line-height:1.9}
.text-link{display:inline-block;color:var(--navy);border-bottom:2px solid var(--gold);padding-bottom:4px;font-weight:750}
.text-link:hover{color:var(--gold-dark)}
.book-intro{background:#fff}
.editorial-grid{display:grid;grid-template-columns:minmax(0,.9fr) minmax(0,1.1fr);gap:clamp(35px,5vw,80px);align-items:center}
.editorial-copy p{font-size:16px;line-height:2.05;color:#43575d;margin:0 0 18px}
.editorial-copy .text-link{margin-top:8px}
.editorial-art{margin:0;overflow:hidden;background:#f1f3f1;border:1px solid var(--line);box-shadow:var(--shadow);border-radius:12px}
.editorial-art img{display:block;width:100%;height:auto;aspect-ratio:3/2;object-fit:cover}
.editorial-art figcaption{padding:10px 16px;background:#fff;color:var(--muted);font-size:12px}
.questions-section{background:#edf3f0}
.question-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}
.question-card{position:relative;background:#fff;padding:29px 30px 31px;border:1px solid var(--line);border-radius:10px;box-shadow:0 9px 25px #173c4709;overflow:hidden}
.question-card:before{content:"";position:absolute;inset:0 0 auto;height:4px;background:linear-gradient(90deg,var(--gold),#bd7765)}
.question-card:nth-child(2):before{background:linear-gradient(90deg,#6f9ba4,#8abdb4)}
.question-card:nth-child(3):before{background:linear-gradient(90deg,#c88b6c,#dfb284)}
.question-mark{font:700 26px Georgia,serif;color:var(--gold-dark);display:flex;align-items:center;gap:14px}
.question-mark span{font:700 10px/1.2 Georgia,serif;letter-spacing:.16em;color:#7a9295}
.question-card h3{font:700 27px "Songti SC","STSong",serif;color:var(--navy);margin:26px 0 8px}
.question-card p{font-size:14px;line-height:1.9;color:var(--muted);margin:0}
.chapters-section{background:var(--paper)}
.chapter-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px}
.chapter-card{display:flex;flex-direction:column;padding:0;min-height:0;border-radius:11px;overflow:hidden;border-color:var(--line);background:#fff}
.chapter-card:hover{border-color:#9bb9b5;box-shadow:0 18px 45px #173c471f}
.chapter-thumb{aspect-ratio:16/9;background:var(--navy-deep);overflow:hidden}
.chapter-thumb img{display:block;width:100%;height:100%;object-fit:cover;transition:transform .35s ease}
.chapter-card:hover .chapter-thumb img{transform:scale(1.035)}
.chapter-card-body{padding:19px 23px 22px;display:flex;flex:1;flex-direction:column}
.chapter-card-meta{display:flex;align-items:center;justify-content:space-between;gap:9px}
.chapter-card .number{font-size:24px}
.chapter-card .small-count{float:none;margin:0;color:#7b8d90;font-size:11px}
.chapter-card h3{font-size:22px;line-height:1.45;margin:12px 0 8px}
.chapter-card p{font-size:13px;line-height:1.85}
.chapter-card .card-link{margin-top:auto;color:var(--navy);padding-top:16px}
.resources{background:#e8f0ee}
.resource-grid{gap:18px}
.resource-card{border-radius:10px;min-height:270px;padding:30px;transition:transform .2s,box-shadow .2s}
.resource-card:hover{transform:translateY(-3px);box-shadow:var(--shadow)}
.resource-card:nth-child(2){background:var(--navy-deep)}
.resource-card h3{font-size:24px}
.resource-card p{font-size:14px}
.authors-preview{background:#fff}
.author-preview-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px}
.author-preview-card{display:grid;grid-template-columns:170px 1fr;background:#fbfbf8;border:1px solid var(--line);border-radius:10px;overflow:hidden;min-height:232px;color:inherit;transition:transform .2s,box-shadow .2s}
.author-preview-card:hover{transform:translateY(-3px);box-shadow:var(--shadow)}
.author-preview-card img{display:block;width:100%;height:100%;object-fit:cover;object-position:50% 30%}
.author-preview-card>div{padding:24px 26px}
.author-preview-card span{color:var(--gold-dark);font-size:11px;font-weight:800}
.author-preview-card h3{font:700 27px "Songti SC","STSong",serif;color:var(--navy);margin:10px 0 7px}
.author-preview-card h3 small{font:500 14px Georgia,serif;color:var(--muted)}
.author-preview-card p{font-size:13px;line-height:1.8;color:var(--muted);margin:0 0 13px}
.author-preview-card strong{font-size:12px;color:var(--navy)}
.page-banner{background:linear-gradient(90deg,rgba(8,29,39,.97),rgba(8,29,39,.77) 62%,rgba(8,29,39,.36)),url('/art/hero-applied.webp') 65% 45%/cover no-repeat;min-height:230px}
.page-banner:before{display:none}
.page-banner h1{font-size:clamp(39px,4vw,53px)}
.page-banner p{color:#d6e5e2}
.authors-list{display:grid;gap:22px}
.author-profile{display:grid;grid-template-columns:240px minmax(0,1fr);gap:clamp(28px,4vw,58px);align-items:start;padding:28px;background:#fff;border:1px solid var(--line);border-radius:12px;scroll-margin-top:100px}
.author-profile img{display:block;width:100%;height:300px;object-fit:cover;object-position:50% 30%;border-radius:7px}
.author-profile h2{margin:12px 0 5px;font-size:37px}
.author-profile h2 small{font:500 16px Georgia,serif;color:var(--muted)}
.author-profile .author-role{color:var(--gold-dark);font-weight:750;margin:0 0 15px}
.author-profile p{font-size:15px;line-height:1.95;color:#42575c}
.author-profile .text-link{margin-top:4px}
.author-links{display:flex;flex-wrap:wrap;gap:12px 26px;align-items:center}
.site-footer{background:#0a202c}
.footer-inner{display:grid;grid-template-columns:1fr auto auto;align-items:center;gap:28px}
.site-footer strong{color:#fff}
.site-footer nav{display:flex;gap:18px}
.site-footer nav a{color:#d7e4e2;font-size:13px}
.site-footer nav a:hover{color:var(--gold)}
.site-footer p{margin:0;color:#b6c8c8}
@media(max-width:1050px){
 .main-nav{gap:8px}.main-nav a{font-size:13px}
 .editorial-grid{grid-template-columns:1fr 1fr;gap:30px}
 .author-preview-card{grid-template-columns:125px 1fr}
}
@media(max-width:760px){
 .site-header{height:68px}
 .header-inner{gap:10px}
 .menu-toggle{display:block;margin-left:auto;flex:0 0 auto}
 .main-nav{display:none;position:absolute;top:68px;left:0;right:0;height:auto;background:#0a202c;padding:10px 18px;box-shadow:0 12px 20px #10274524}
 .main-nav.open{display:grid;gap:0}
 .main-nav a{color:#f0f4f2;border-color:#ffffff22;padding:11px}
 .hero-grid{min-height:590px}
 .hero-copy{padding:65px 0;min-width:0;width:100%}
 .hero{background:linear-gradient(90deg,rgba(5,20,31,.93),rgba(5,20,31,.68)),url('/art/hero-applied.webp') 58% center/cover no-repeat}
 .editorial-grid,.question-grid,.author-preview-grid,.author-profile{grid-template-columns:1fr}
 .editorial-art{max-width:650px}
 .chapter-grid{grid-template-columns:repeat(2,minmax(0,1fr))}
 .author-preview-card{grid-template-columns:150px 1fr}
 .author-profile img{width:220px;height:275px}
 .footer-inner{grid-template-columns:1fr;gap:15px}
}
@media(max-width:540px){
 .brand{font-size:17px}
 .brand small{font-size:7px;letter-spacing:.12em}
 .hero h1{font-size:43px}
 .hero-detail{font-size:14px}
 .stat-grid{padding:15px 0}
 .stat-grid strong{font-size:26px}
 .stat-grid>div:last-child strong{font-size:22px;white-space:nowrap}
 .section-head{align-items:start;flex-direction:column}
 .chapter-grid{grid-template-columns:1fr}
 .author-preview-card{grid-template-columns:125px 1fr}
 .author-preview-card>div{padding:18px}
 .author-preview-card h3{font-size:21px}
 .author-preview-card h3 small{display:block;margin-top:3px}
 .site-footer nav{flex-wrap:wrap}
}

.sister-book{margin-top:22px!important;font-size:14px!important}
.sister-book a{color:var(--navy);text-decoration:underline;text-decoration-color:var(--gold);text-underline-offset:4px}
.sister-book cite{font-style:normal}
.site-footer .sister-footer{display:inline-block;margin-top:9px;color:#e8ba7a;font-size:13px}
.site-footer .sister-footer:hover{color:#fff}