/* 91APP editorial visual system */
:root{--forest:#294B3A;--forest-deep:#1D3529;--moss:#71836A;--mist:#E6ECE3;--wood:#76543B;--wood-deep:#443329;--gold:#C59A3D;--pale-gold:#F3E8C8;--paper:#F7F5EE;--white:#fff;--ink:#26342B;--body:#343A33;--muted:#62685F;--line:#D9D8CC;--max:1220px;--reading:760px;--shadow:0 8px 24px rgba(29,53,41,.06)}
*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:92px}
body{margin:0;background:var(--paper);color:var(--body);font-family:system-ui,-apple-system,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;font-size:16px;line-height:1.82;overflow-wrap:break-word}
img{display:block;max-width:100%;width:auto;height:auto;object-fit:contain}
a{color:var(--forest);text-decoration-thickness:1px;text-underline-offset:4px;overflow-wrap:anywhere}
a:hover{color:var(--wood)}
button{font:inherit}
:focus-visible{outline:3px solid var(--gold);outline-offset:3px;border-radius:4px}
.skip-link{position:absolute;left:12px;top:-60px;z-index:1000;background:var(--white);color:var(--forest-deep);padding:10px 14px;border:2px solid var(--gold);border-radius:6px}
.skip-link:focus{top:10px}
.site-header{position:relative;z-index:20;background:var(--white);border-bottom:1px solid var(--line)}
.header-inner{max-width:var(--max);min-height:76px;margin:0 auto;padding:10px 30px;display:flex;align-items:center;gap:24px}
.brand{display:flex;align-items:center;gap:12px;min-width:0;text-decoration:none;color:var(--forest-deep)}
.brand-image{max-width:180px;max-height:36px;width:auto;height:auto}
.brand-wordmark,.footer-wordmark{font-weight:850;font-size:25px;letter-spacing:-1.2px;color:var(--forest-deep);white-space:nowrap}
.brand-wordmark span,.footer-wordmark span{color:var(--wood)}
.brand-tagline{font-size:12px;color:var(--muted);line-height:1.35;max-width:125px}
.primary-nav{display:flex;align-items:center;justify-content:center;gap:clamp(10px,1.55vw,23px);margin-left:auto;min-width:0}
.primary-nav a,.route-link{font-size:14px;font-weight:650;text-decoration:none;color:var(--body);padding:9px 0;border-bottom:2px solid transparent;white-space:nowrap}
.primary-nav a:hover,.route-link:hover,.primary-nav a[aria-current=page],.route-link[aria-current=page]{color:var(--forest);border-color:var(--gold)}
.header-actions{display:flex;align-items:center;gap:18px;flex-shrink:0}
.menu-toggle{display:inline-flex;align-items:center;justify-content:center;gap:9px;min-height:44px;padding:8px 13px;border:1px solid var(--forest);border-radius:7px;background:var(--forest);color:var(--white);font-size:14px;font-weight:700;cursor:pointer}
.menu-toggle:hover{background:var(--forest-deep)}
.menu-icon{width:16px;display:grid;gap:3px}.menu-icon i{display:block;height:2px;background:currentColor;border-radius:2px}
.topic-panel{background:var(--mist);border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.topic-panel[hidden]{display:none!important}
.topic-panel-inner{max-width:var(--max);margin:0 auto;padding:26px 30px 30px;display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:22px}
.topic-group{min-width:0}.topic-group h2{font-size:16px;color:var(--forest-deep);margin:0 0 4px}.topic-group>p{font-size:12px;color:var(--muted);margin:0 0 12px;line-height:1.6}
.topic-group ul,.footer-index ul,.footer-service ul{list-style:none;margin:0;padding:0}.topic-group li+li{margin-top:6px}
.topic-group a{display:block;padding:7px 8px;border-radius:6px;text-decoration:none;color:var(--body);min-width:0}.topic-group a:hover,.topic-group a[aria-current=page]{background:var(--white);color:var(--forest)}
.topic-group strong{display:block;font-size:14px}.topic-group small{display:block;font-size:12px;color:var(--muted);line-height:1.5;margin-top:1px;overflow-wrap:anywhere}
.main-content{min-height:55vh}
.page-shell,.home-shell{max-width:var(--max);margin:0 auto;padding:25px 30px 76px;min-width:0}
.breadcrumbs{display:flex;flex-wrap:wrap;gap:9px;align-items:center;color:var(--muted);font-size:13px;margin:0 0 18px}.breadcrumbs a{color:var(--muted)}.breadcrumbs [aria-current=page]{color:var(--forest-deep);font-weight:650}
.page-heading{max-width:900px;margin:0 0 24px}.eyebrow{font-size:13px;letter-spacing:.08em;color:var(--wood);font-weight:750;margin:0 0 7px}
h1,h2,h3{color:var(--ink);line-height:1.35;overflow-wrap:anywhere}h1{font-size:clamp(27px,3vw,38px);letter-spacing:-.025em;margin:0 0 13px;font-weight:800}.page-intro{font-size:17px;line-height:1.85;color:#4B554B;margin:0;max-width:850px}
.article-index{display:flex;align-items:flex-start;gap:18px;flex-wrap:wrap;padding:13px 16px;margin:24px 0 42px;background:var(--white);border:1px solid var(--line);border-left:3px solid var(--gold);border-radius:8px}.article-index>span{font-size:13px;font-weight:750;color:var(--forest);padding-top:2px}.article-index ol{display:flex;flex-wrap:wrap;gap:7px 18px;margin:0;padding-left:20px;font-size:13px}.article-index a{text-decoration:none;color:var(--muted)}.article-index a:hover{color:var(--forest);text-decoration:underline}
.article-section{display:grid;grid-template-columns:48px minmax(0,1fr);gap:18px;max-width:var(--reading);margin:0 auto 42px;padding-bottom:34px;border-bottom:1px solid var(--line);min-width:0}.section-kicker{font-size:13px;font-weight:800;color:var(--gold);padding-top:5px;letter-spacing:.06em}.section-content{min-width:0}.section-content h2{font-size:24px;margin:0 0 16px;font-weight:760}.section-content h3{font-size:18px;margin:22px 0 8px}.section-content p{font-size:16px;line-height:1.9;margin:0 0 14px}.detail-list,.step-list{padding-left:22px;margin:15px 0 18px}.detail-list li,.step-list li{padding-left:4px;margin:6px 0;line-height:1.8}.detail-list li::marker{color:var(--moss)}.step-list li::marker{color:var(--wood);font-weight:800}.editor-note{margin:20px 0 0;padding:14px 17px;background:var(--mist);border-radius:8px;border-left:3px solid var(--moss)}.editor-note strong{font-size:13px;color:var(--forest)}.editor-note p{margin:4px 0 0;font-size:15px}.section-comparison .section-content{padding:18px 20px;background:#fff;border:1px solid var(--line);border-radius:9px}.section-timeline .section-content{padding:18px 20px;background:var(--pale-gold);border-radius:9px}.section-quote blockquote,.section-content blockquote{margin:18px 0;padding:12px 18px;border-left:3px solid var(--gold);background:#fff;color:var(--wood-deep);font-size:17px}
.table-wrap{max-width:100%;overflow-x:auto;margin:18px 0;border:1px solid var(--line);border-radius:8px;background:#fff}.responsive-table{width:100%;min-width:560px;border-collapse:collapse;table-layout:fixed;font-size:14px;line-height:1.65}.responsive-table th,.responsive-table td{padding:11px 12px;text-align:left;vertical-align:top;border-bottom:1px solid var(--line);overflow-wrap:anywhere}.responsive-table th{background:var(--mist);color:var(--forest-deep);font-weight:750}.responsive-table tr:last-child td{border-bottom:0}.faq-list{max-width:var(--reading);margin:0 auto}.faq-item{padding:20px 0 22px;border-bottom:1px solid var(--line)}.faq-item h2{font-size:19px;margin:0 0 9px;color:var(--forest)}.faq-item p{margin:0;font-size:16px;line-height:1.85}.related-reading{max-width:var(--reading);margin:58px auto 0}.related-reading h2{font-size:21px;margin:0 0 16px}.related-reading ul{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px;list-style:none;padding:0;margin:0}.related-reading a{height:100%;display:block;padding:14px 15px;border:1px solid var(--line);border-radius:8px;background:var(--white);text-decoration:none}.related-reading a:hover{border-color:var(--moss);box-shadow:var(--shadow)}.related-reading strong{display:block;font-size:15px;color:var(--forest)}.related-reading span{display:block;font-size:13px;line-height:1.6;color:var(--muted);margin-top:5px}
.media-frame{margin:20px 0 26px;padding:12px;max-width:100%;width:fit-content;background:var(--white);border:1px solid var(--line);border-radius:10px}.media-frame img{max-width:100%;max-height:380px;width:auto;height:auto;object-fit:contain;margin:0 auto}.home-hero .media-frame{max-width:500px;max-height:340px}.home-hero .media-frame img{max-height:310px}.home-module .media-frame{max-width:440px}.home-module .media-frame img{max-height:260px}
.site-footer{background:var(--forest-deep);color:#F5F4ED;padding:46px 0 18px}.footer-inner{max-width:var(--max);margin:0 auto;padding:0 30px;display:grid;grid-template-columns:1.1fr 3fr .9fr;gap:36px}.footer-brand p{max-width:220px;color:#D7DFD5;font-size:14px;line-height:1.7}.footer-brand>a:not(.footer-wordmark){color:#F3E8C8;font-size:14px}.footer-wordmark{display:inline-block;color:#fff;text-decoration:none}.footer-wordmark span{color:#E0C27A}.footer-index{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:18px}.footer-index h2,.footer-service h2{font-size:14px;color:#F3E8C8;margin:0 0 10px}.footer-index li,.footer-service li{margin:5px 0}.footer-index a,.footer-service a{font-size:13px;color:#E4E9E1;text-decoration:none}.footer-index a:hover,.footer-service a:hover{color:#F3D88E;text-decoration:underline}.footer-bottom{max-width:var(--max);margin:30px auto 0;padding:14px 30px 0;border-top:1px solid rgba(255,255,255,.2);display:flex;justify-content:space-between;gap:16px;color:#D7DFD5;font-size:12px}.footer-bottom a{color:#F3E8C8}
.mobile-quickbar{display:none}
/* Home editorial composition */
.home-shell{padding-top:34px}.home-hero{display:grid;grid-template-columns:minmax(0,7fr) minmax(0,5fr);align-items:center;gap:40px;padding:26px 0 54px;border-bottom:1px solid var(--line)}.home-hero.no-media{grid-template-columns:minmax(0,1fr)}.home-module.no-media,.home-module.reverse.no-media,.sound-band .home-module.no-media{grid-template-columns:minmax(0,1fr)}.home-hero-copy{min-width:0}.home-hero h1{font-size:clamp(32px,3.5vw,45px);margin:0 0 13px}.home-claim{font-size:22px;line-height:1.55;color:var(--forest);font-weight:720;max-width:600px;margin:0 0 12px}.home-hero-copy>p:not(.home-claim){max-width:650px;font-size:17px;line-height:1.85;color:#4D574E;margin:0 0 22px}.home-actions{display:flex;flex-wrap:wrap;gap:12px}.text-action{display:inline-flex;align-items:center;min-height:44px;padding:8px 15px;border-radius:7px;background:var(--forest);color:#fff;text-decoration:none;font-weight:700}.text-action.secondary{background:transparent;border:1px solid var(--forest);color:var(--forest)}.text-action:hover{background:var(--forest-deep);color:#fff}.home-hero .media-frame{justify-self:end;margin:0}.home-section{padding:48px 0;border-bottom:1px solid var(--line)}.home-section-heading{display:flex;align-items:flex-end;justify-content:space-between;gap:20px;margin-bottom:22px}.home-section-heading p{margin:0;color:var(--muted);font-size:14px;max-width:500px}.home-section h2{font-size:25px;margin:0}.observation-index{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:10px}.observation-index a{padding:17px 14px;background:#fff;border:1px solid var(--line);border-radius:8px;text-decoration:none;min-width:0}.observation-index strong{display:block;color:var(--forest);font-size:17px}.observation-index span{display:block;color:var(--muted);font-size:13px;line-height:1.6;margin-top:5px}.home-module{display:grid;grid-template-columns:minmax(0,1.05fr) minmax(0,.95fr);gap:34px;align-items:center;min-width:0}.home-module.reverse{grid-template-columns:minmax(0,.9fr) minmax(0,1.1fr)}.home-module-copy{min-width:0}.home-module-copy h2{font-size:25px;margin:0 0 12px}.home-module-copy p{font-size:16px;line-height:1.85;margin:0 0 14px}.home-module .media-frame{margin:0 auto}.annotation-list{list-style:none;padding:0;margin:14px 0 0;display:grid;gap:9px}.annotation-list li{padding-left:18px;position:relative;font-size:14px}.annotation-list li::before{content:"";position:absolute;left:0;top:.72em;width:7px;height:7px;border-radius:50%;background:var(--gold)}.sound-band{background:var(--mist);padding:34px;border:1px solid #D6DED2;border-radius:10px}.sound-band .home-module{grid-template-columns:minmax(0,1fr) minmax(0,.8fr)}.sound-dimensions{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;margin-top:16px}.sound-dimensions span{padding:10px 12px;background:#fff;border-radius:6px;color:var(--forest);font-size:14px;font-weight:650}.timeline{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:0;margin:20px 0 16px}.timeline div{position:relative;padding:15px 12px 12px;border-top:2px solid var(--gold);min-width:0}.timeline b{display:block;color:var(--forest);font-size:16px}.timeline span{display:block;font-size:13px;color:var(--muted);margin-top:5px}.creative-steps{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px;margin-top:18px}.creative-steps span{padding:12px;background:#fff;border:1px solid var(--line);border-radius:7px;font-size:14px}.creative-steps b{color:var(--wood);margin-right:7px}.home-check{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);background:var(--white);border-radius:10px;overflow:hidden;border:1px solid var(--line)}.home-check-title{background:var(--forest-deep);color:#fff;padding:28px}.home-check-title h2{color:#fff;margin:0 0 10px;font-size:25px}.home-check-title p{color:#E3E9E1;margin:0}.home-check-body{padding:26px}.check-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.check-grid div{padding:12px;background:var(--paper);border-radius:7px}.check-grid strong{display:block;color:var(--forest);font-size:15px}.check-grid span{font-size:13px;color:var(--muted)}.service-links{display:flex;flex-wrap:wrap;gap:10px 18px;margin-top:17px}.service-links a{font-size:14px;font-weight:650}
@media(max-width:1100px){.header-inner{gap:15px}.brand-tagline{display:none}.primary-nav{gap:12px}.primary-nav a,.route-link{font-size:13px}.topic-panel-inner{grid-template-columns:repeat(3,minmax(0,1fr))}.footer-inner{grid-template-columns:1fr 2.7fr}.footer-service{grid-column:2}.footer-index{grid-template-columns:repeat(3,minmax(0,1fr))}}
@media(max-width:820px){.header-inner{min-height:68px;padding:9px 22px;gap:12px}.primary-nav{display:none}.header-actions{margin-left:auto;gap:14px}.route-link{font-size:14px}.topic-panel-inner{padding:20px 22px;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}.page-shell,.home-shell{padding-left:22px;padding-right:22px}.home-hero{gap:24px}.home-module,.home-module.reverse{gap:22px}.observation-index{grid-template-columns:repeat(3,minmax(0,1fr))}.footer-inner{padding:0 22px;grid-template-columns:1fr}.footer-index{grid-template-columns:repeat(3,minmax(0,1fr))}.footer-service{grid-column:auto}.footer-bottom{padding-left:22px;padding-right:22px}}
@media(max-width:600px){html{scroll-padding-top:75px}.header-inner{min-height:64px;padding:8px 16px}.brand{gap:0}.brand-image{max-width:150px;max-height:32px}.brand-wordmark{font-size:23px}.header-actions{gap:10px}.route-link{font-size:13px;padding:7px 0}.menu-toggle{min-height:44px;padding:7px 10px;font-size:13px;gap:7px}.topic-panel-inner{grid-template-columns:minmax(0,1fr);padding:16px}.topic-group{padding-bottom:12px;border-bottom:1px solid #D3DCCF}.topic-group:last-child{border-bottom:0}.topic-group ul{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:3px 8px}.topic-group li+li{margin-top:0}.page-shell,.home-shell{padding:19px 16px 90px}.breadcrumbs{margin-bottom:14px;font-size:12px}.page-heading{margin-bottom:18px}.eyebrow{font-size:12px}.page-intro{font-size:16px;line-height:1.8}.article-index{margin:18px 0 30px;padding:12px;gap:8px}.article-index ol{gap:5px 14px}.article-section{grid-template-columns:28px minmax(0,1fr);gap:10px;margin-bottom:32px;padding-bottom:27px}.section-content h2{font-size:21px;margin-bottom:12px}.section-content p{font-size:16px;line-height:1.85}.section-kicker{font-size:12px}.related-reading{margin-top:40px}.related-reading ul{grid-template-columns:minmax(0,1fr)}.media-frame{padding:10px;margin:16px auto 22px}.media-frame img{max-height:300px}.home-shell{padding-top:20px}.home-hero{grid-template-columns:minmax(0,1fr);gap:18px;padding:10px 0 34px}.home-hero h1{font-size:33px}.home-claim{font-size:20px}.home-hero-copy>p:not(.home-claim){font-size:16px}.home-hero .media-frame{justify-self:start;max-width:100%;margin:0}.home-hero .media-frame img{max-height:230px}.home-section{padding:34px 0}.home-section-heading{display:block;margin-bottom:16px}.home-section-heading p{margin-top:6px}.home-section h2,.home-module-copy h2{font-size:22px}.observation-index{grid-template-columns:repeat(2,minmax(0,1fr));gap:8px}.observation-index a{padding:13px 11px}.home-module,.home-module.reverse,.sound-band .home-module{grid-template-columns:minmax(0,1fr);gap:16px}.home-module .media-frame{grid-row:2;justify-self:start;margin:0}.sound-band{padding:18px}.sound-dimensions{grid-template-columns:repeat(2,minmax(0,1fr))}.timeline{grid-template-columns:repeat(2,minmax(0,1fr));row-gap:10px}.creative-steps{grid-template-columns:repeat(2,minmax(0,1fr))}.home-check{grid-template-columns:minmax(0,1fr)}.home-check-title,.home-check-body{padding:20px}.check-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.footer-inner{padding:0 16px;gap:26px}.footer-index{grid-template-columns:repeat(2,minmax(0,1fr));gap:18px}.footer-bottom{margin-top:22px;padding:12px 16px 8px;flex-wrap:wrap}.site-footer{padding-top:34px;padding-bottom:82px}.mobile-quickbar{position:fixed;z-index:30;left:0;right:0;bottom:0;min-height:58px;padding:5px 14px calc(5px + env(safe-area-inset-bottom));display:grid;grid-template-columns:repeat(3,minmax(0,1fr));background:rgba(255,255,255,.98);border-top:1px solid var(--line)}.mobile-quickbar a{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:0;min-height:48px;color:var(--muted);font-size:12px;text-decoration:none}.mobile-quickbar a span{font-size:17px;line-height:1.25;color:var(--forest)}.mobile-quickbar a[aria-current=page]{color:var(--forest);font-weight:750}.mobile-quickbar a[aria-current=page] span{color:var(--wood)}}
@media(max-width:360px){.brand-wordmark{font-size:21px}.route-link{font-size:12px}.header-actions{gap:8px}.menu-toggle{padding:6px 8px;font-size:12px}.menu-icon{width:13px}.topic-group ul{grid-template-columns:minmax(0,1fr)}.observation-index{grid-template-columns:minmax(0,1fr)}.sound-dimensions,.check-grid,.creative-steps{grid-template-columns:minmax(0,1fr)}.timeline{grid-template-columns:minmax(0,1fr)}.article-section{grid-template-columns:23px minmax(0,1fr);gap:8px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*::before,*::after{animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important}}