/* R2U Guides & Insights, owner-approved 15 Oct 2026.
 * Editorial polish is scoped to guide pages, related-reading cards and Guides nav.
 * Preserve existing product application logic, evidence images and commercial CTAs.
 */
:root{--r2u-guides-deep:#102b40;--r2u-guides-ink:#1a3d50;--r2u-guides-muted:#5c7481;--r2u-guides-blue:#0874b6;--r2u-guides-border:#dce8ec;--r2u-guides-paper:#f6fafb}
.r2u-guide-category{font-size:.75rem;line-height:1.5;letter-spacing:.10em;font-weight:800;color:#21789a;margin:0 0 .8rem}
body.r2u-brand .site-header .desktop-nav a[href="/guides/"][aria-current="page"],
body.r2u-brand .site-header .desktop-nav a[href="/guides/"]:hover{color:#fff}
.r2u-guide-breadcrumb{display:flex;align-items:center;gap:.65rem;flex-wrap:wrap;color:#b5d2df;font-size:.85rem;line-height:1.5;margin:0 0 clamp(2rem,4vw,3.5rem)}
.r2u-guide-breadcrumb a{color:inherit;text-decoration:none}
.r2u-guide-breadcrumb a:hover{text-decoration:underline;text-underline-offset:4px}
.r2u-guides-hero{background:radial-gradient(ellipse at 82% 40%,#24526970,transparent 46%),linear-gradient(140deg,#132f43,#081c2c);color:#e9f6fc;padding:clamp(2.8rem,6vw,5.8rem) 0 clamp(4.5rem,7vw,7.5rem)}
.r2u-guides-eyebrow{color:#8fc7e0;font-size:.77rem;font-weight:850;letter-spacing:.115em;margin:0 0 1.1rem}
.r2u-guides-hero h1{font-size:clamp(2.9rem,6vw,5.3rem);font-weight:750;letter-spacing:-.056em;line-height:1.1;max-width:19ch;margin:0 0 1.5rem;text-wrap:balance}
.r2u-guides-hero>div>p{font-size:clamp(1.04rem,1.7vw,1.26rem);color:#bbd4e1;line-height:1.72;max-width:67ch;margin:0 0 1.8rem}
.r2u-guide-hero-stat{display:flex;align-items:center;gap:.8rem;flex-wrap:wrap;color:#9ac5d9;font-size:.85rem;font-weight:650}
.r2u-guides-library{padding:clamp(4rem,7vw,7.5rem) 0;background:var(--r2u-guides-paper)}
.r2u-guides-library-head{display:flex;align-items:end;justify-content:space-between;gap:2rem;flex-wrap:wrap;margin:0 0 2.5rem}
.r2u-guides-library-head h2{font-size:clamp(2rem,4vw,3.35rem);font-weight:730;letter-spacing:-.045em;color:var(--r2u-guides-ink);margin:0}
.r2u-guides-library-head>p{color:var(--r2u-guides-muted);max-width:37ch;margin:0;line-height:1.75;font-size:1rem}
.r2u-guides-card-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:1.4rem}
.r2u-guide-card{min-width:0;background:#fff;border:1px solid var(--r2u-guides-border);border-radius:18px;overflow:hidden;display:flex;flex-direction:column;transition:box-shadow .2s ease,transform .2s ease}
.r2u-guide-card:hover{box-shadow:0 20px 50px #17354613;transform:translateY(-2px)}
.r2u-guide-card-featured{grid-column:1/-1;display:grid;grid-template-columns:minmax(0,.94fr) minmax(0,1.06fr)}
.r2u-guide-card-img{display:flex;align-items:center;justify-content:center;background:radial-gradient(circle at 70% 35%,#e2f1f6,#edf5f9);padding:1.6rem;aspect-ratio:16/9;border-bottom:1px solid var(--r2u-guides-border);min-width:0}
.r2u-guide-card-featured .r2u-guide-card-img{aspect-ratio:auto;min-height:330px;border:0;border-right:1px solid var(--r2u-guides-border)}
.r2u-guide-card-img img{display:block;max-width:100%;width:100%;height:auto;max-height:280px;object-fit:contain;box-shadow:0 15px 36px #153e4d15;border-radius:9px}
.r2u-guide-card-copy{padding:clamp(1.4rem,3vw,2.35rem);display:flex;flex-direction:column;align-items:start;flex:1;gap:.6rem}
.r2u-guide-card-copy h3{font-size:clamp(1.48rem,2.2vw,2.15rem);letter-spacing:-.035em;font-weight:740;line-height:1.22;margin:0 0 .3rem;color:var(--r2u-guides-ink)}
.r2u-guide-card-copy h3>a{text-decoration:none;color:inherit}
.r2u-guide-card-copy h3>a:hover{color:#096b9a}
.r2u-guide-card-copy p{color:var(--r2u-guides-muted);font-size:1rem;line-height:1.75;margin:0 0 1.1rem}
.r2u-guide-arrow,.r2u-guide-home-all{font-size:.91rem;color:var(--r2u-guides-blue);font-weight:750;text-decoration:none;display:inline-flex;align-items:center;gap:.6rem;min-height:44px}
.r2u-guide-arrow:hover,.r2u-guide-home-all:hover{text-decoration:underline;text-underline-offset:4px}
.r2u-guides-closing{padding:clamp(3.5rem,6vw,5.4rem) 0;background:#102e43;color:#eaf7fd}
.r2u-guides-closing>.container{display:flex;align-items:center;justify-content:space-between;gap:2rem;flex-wrap:wrap}
.r2u-guides-closing h2{font-size:clamp(1.9rem,3.5vw,3rem);letter-spacing:-.045em;max-width:22ch;font-weight:750;color:#fff;margin:0 0 .8rem}
.r2u-guides-closing p{max-width:60ch;color:#b2d0df;font-size:1rem;line-height:1.75;margin:0}
.r2u-guides-closing a{flex:0 1 auto;display:inline-flex;align-items:center;justify-content:center;min-height:48px;padding:13px 19px;border-radius:999px;color:#fff;background:#0b73af;border:1px solid #5c9cbe;font-weight:750;font-size:.95rem}
.r2u-guides-closing a:hover{background:#096297}
.r2u-guide-article-hero{background:radial-gradient(ellipse at 90% 20%,#32617a73,transparent 50%),linear-gradient(145deg,#153448,#0b2233);color:#ecf8fd;padding:clamp(2.8rem,5vw,5.2rem) 0 clamp(4rem,6vw,6rem)}
.r2u-guide-article-hero h1{font-size:clamp(2.5rem,5.45vw,4.9rem);font-weight:750;letter-spacing:-.057em;line-height:1.12;max-width:21ch;margin:0 0 1.3rem;text-wrap:balance}
.r2u-guide-article-hero .r2u-guide-category{color:#7ac9ef}
.r2u-guide-dek{font-size:clamp(1.02rem,1.75vw,1.2rem);line-height:1.75;color:#c0d7e3;max-width:72ch;margin:0 0 1.5rem}
.r2u-guide-meta{display:flex;gap:.7rem;align-items:center;flex-wrap:wrap;font-size:.87rem;color:#b6cfdb;font-weight:600}
.r2u-guide-article-wrap{background:#fff;padding:0 0 clamp(3rem,6vw,6rem)}
.r2u-guide-featured-figure{position:relative;max-width:950px;margin:-3rem auto 3.1rem;padding:clamp(1.3rem,2.6vw,2rem);background:#f5fafc;border:1px solid #d8e6ec;box-shadow:0 26px 65px #092d381b;border-radius:18px}
.r2u-guide-featured-figure>img{display:block;width:100%;height:auto;max-height:420px;object-fit:contain;margin:0 auto;border-radius:9px;background:#ecf3f7}
.r2u-guide-featured-figure figcaption{font-size:.78rem;line-height:1.65;color:#627c89;margin-top:1rem}
.r2u-guide-body-grid{display:grid;grid-template-columns:minmax(0,760px) minmax(215px,1fr);gap:clamp(2rem,5vw,4.5rem);align-items:start}
.r2u-guide-prose{font-size:1.05rem;line-height:1.88;color:#344f5f;min-width:0}
.r2u-guide-prose>p,.r2u-guide-prose>ul,.r2u-guide-prose>blockquote{max-width:74ch}
.r2u-guide-prose>p{margin:0 0 1.2rem}
.r2u-guide-prose h2{font-size:clamp(1.5rem,2.4vw,2rem);line-height:1.3;letter-spacing:-.035em;font-weight:750;color:#183b4f;margin:3.1rem 0 1.2rem;scroll-margin-top:130px}
.r2u-guide-prose h3{font-size:1.18rem;line-height:1.35;letter-spacing:-.016em;font-weight:750;color:#224456;margin:1.85rem 0 .65rem}
.r2u-guide-prose>ul{padding-left:1.4rem;margin:0 0 1.6rem}
.r2u-guide-prose>ul li{margin:.5rem 0;padding-left:.15rem}
.r2u-guide-prose strong{color:#173e52;font-weight:750}
.r2u-guide-prose a{color:#0875b4;text-decoration:underline;text-underline-offset:3px}
.r2u-guide-prose a:hover{color:#074b7b}
.r2u-guide-prose blockquote{margin:1.3rem 0 2rem;border-left:3px solid #41a5d1;padding:.6rem 0 .6rem 1.3rem;color:#24526a;font-weight:600;font-size:1.22rem}
.r2u-guide-prose blockquote p{margin:0}
.r2u-guide-table-scroll{width:100%;overflow-x:auto;margin:1.6rem 0 2rem}
.r2u-guide-prose table{width:100%;border-collapse:collapse;min-width:440px;font-size:.95rem;line-height:1.6;text-align:left}
.r2u-guide-prose table caption{text-align:left;color:#6b8390;font-size:.78rem;line-height:1.5;margin-bottom:.55rem}
.r2u-guide-prose table th{font-weight:800;color:#21475c}
.r2u-guide-prose table td,.r2u-guide-prose table th{padding:12px 14px;border-bottom:1px solid #dbe6ec;vertical-align:top}
.r2u-guide-prose table thead{background:#eaf3f7}
.r2u-guide-prose table tbody tr:nth-child(even){background:#f7fafb}
.r2u-guide-side{min-width:0}
.r2u-guide-side-sticky{position:sticky;top:105px;display:grid;gap:1rem}
.r2u-guide-side-box{padding:1.3rem;border:1px solid #dbe8ec;background:#f8fbfc;border-radius:13px}
.r2u-guide-side-box nav{display:flex;flex-direction:column;gap:0}
.r2u-guide-side-box nav a{display:block;color:#527080;font-size:.88rem;line-height:1.5;text-decoration:none;padding:.61rem 0;border-bottom:1px solid #e0e9ee}
.r2u-guide-side-box nav a:last-child{border-bottom:0}
.r2u-guide-side-box nav a:hover{color:#096d9f;text-decoration:underline}
.r2u-guide-side-product strong{display:block;font-size:1.23rem;letter-spacing:-.025em;color:#21445a;margin:.2rem 0 .8rem}
.r2u-guide-side-product a{color:#0b76b3;font-weight:750;text-decoration:none;font-size:.9rem;display:inline-flex;align-items:center;min-height:44px}
.r2u-guide-article-cta{border:1px solid #d6e6ec;background:#eff7fa;border-radius:15px;padding:clamp(1.35rem,2.9vw,2.25rem);margin-top:3.5rem}
.r2u-guide-prose .r2u-guide-article-cta h2{font-size:clamp(1.5rem,2.7vw,2rem);margin:.2rem 0 .75rem}
.r2u-guide-article-cta p:not(.r2u-guide-category){font-size:1rem;line-height:1.68;margin:0 0 1.1rem}
.r2u-guide-article-cta>a{display:inline-flex;align-items:center;min-height:46px;font-size:.9rem;font-weight:750;color:#fff;background:#0c6da6;border:1px solid #0b75b8;text-decoration:none;border-radius:999px;padding:10px 16px}
.r2u-guide-article-cta>a:hover{background:#075a91;color:white}
.r2u-guide-more{background:#f5f9fb;border-top:1px solid #e1ebef;padding:clamp(3.5rem,5vw,5rem) 0}
.r2u-guide-more-head{display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:1rem;margin-bottom:1.5rem}
.r2u-guide-more h2{font-size:clamp(2rem,3.6vw,3rem);letter-spacing:-.035em;margin:0;color:#1d4155}
.r2u-guide-more-head>a{font-size:.94rem;font-weight:750;color:#0c6ea6;text-decoration:none}
.r2u-guide-more ul{list-style:none;padding:0;margin:0;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:1rem}
.r2u-guide-more li a{display:flex;justify-content:space-between;align-items:center;gap:1rem;padding:1.35rem;background:#fff;border:1px solid #d9e6ec;color:#264a5e;border-radius:12px;min-height:110px;font-weight:750;text-decoration:none;line-height:1.4}
.r2u-guide-more li a:hover{border-color:#9fcce0;color:#0c6fa5}
.r2u-guide-home-band{background:#edf5f9;border-top:1px solid #dceaf0;padding:clamp(3.5rem,5vw,5.5rem) 0}
.r2u-guide-home-heading{display:flex;align-items:end;justify-content:space-between;flex-wrap:wrap;gap:1.5rem;margin-bottom:2rem}
.r2u-guide-home-heading h2{font-size:clamp(2rem,4vw,3.3rem);line-height:1.16;letter-spacing:-.05em;font-weight:740;color:#1c4256;margin:0 0 .7rem}
.r2u-guide-home-heading p:not(.r2u-guide-category){color:#607987;font-size:1rem;max-width:60ch;line-height:1.7;margin:0}
.r2u-guide-home-list{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:1rem}
.r2u-guide-home-list>a{min-width:0;padding:1.3rem;min-height:180px;border:1px solid #d8e5ed;background:#fff;border-radius:13px;display:flex;flex-direction:column;gap:.7rem;text-decoration:none}
.r2u-guide-home-list>a>span:first-child{font-size:.7rem;letter-spacing:.07em;color:#24789b;font-weight:800}
.r2u-guide-home-list>a>strong{font-size:1.1rem;line-height:1.38;color:#1c4054;letter-spacing:-.017em;font-weight:740}
.r2u-guide-home-list>a>span:last-child{margin-top:auto;align-self:flex-end;color:#0c7bab;font-size:1.2rem}
.r2u-guide-home-list>a:hover{border-color:#99cce4;box-shadow:0 10px 28px #0638490a}
.r2u-guide-product-related{border-top:1px solid #d9e8ef;background:#edf5f9;padding:clamp(2.5rem,4.6vw,4.5rem) 0}
.r2u-guide-product-related-inner{display:flex;justify-content:space-between;align-items:center;gap:2rem;flex-wrap:wrap}
.r2u-guide-product-related h2{font-size:clamp(1.5rem,3vw,2.5rem);line-height:1.18;letter-spacing:-.04em;color:#1d4155;margin:0 0 .65rem}
.r2u-guide-product-related p:not(.r2u-guide-category){font-size:1rem;line-height:1.65;color:#597586;margin:0}
.r2u-guide-product-related-inner>a{flex:0 1 400px;display:inline-flex;align-items:center;justify-content:space-between;gap:1rem;color:#0a689b;font-size:1rem;font-weight:760;text-decoration:none;line-height:1.5;padding:1rem 1.2rem;border-radius:13px;border:1px solid #b9dce9;background:#fff}
.r2u-guide-product-related-inner>a:hover{border-color:#66afd0;text-decoration:underline}
body.r2u-brand :is(.r2u-guide-card,.r2u-guide-arrow,.r2u-guide-more a,.r2u-guide-product-related a):focus-within{outline-color:#268cc0}
body.r2u-brand :is(.r2u-guide-arrow,.r2u-guide-card a,.r2u-guide-breadcrumb a,.r2u-guide-prose a,.r2u-guide-side a,.r2u-guide-more a,.r2u-guide-home-list a):focus-visible{outline:3px solid #3fa6d7;outline-offset:4px;border-radius:4px}
/* With a fifth top-level link, use the existing mobile menu slightly sooner
   to preserve readable labels at medium desktop widths. */
@media(max-width:1160px){
 body.r2u-brand .site-header .desktop-nav{display:none}
 body.r2u-brand .site-header .menu-toggle{display:flex}
}
@media(max-width:900px){
 .r2u-guide-body-grid{grid-template-columns:minmax(0,1fr)}
 .r2u-guide-side{display:none}
 .r2u-guide-card-featured{display:flex;grid-column:1;flex-direction:column}
 .r2u-guide-card-featured .r2u-guide-card-img{aspect-ratio:16/9;min-height:0;border-right:0;border-bottom:1px solid #dce8ec}
 .r2u-guide-article-hero h1{max-width:25ch}
}
@media(max-width:720px){
 .r2u-guides-card-grid{grid-template-columns:1fr}
 .r2u-guide-card-featured{grid-column:1}
 .r2u-guide-home-list{grid-template-columns:1fr}
 .r2u-guide-home-list>a{min-height:140px}
 .r2u-guide-more ul{grid-template-columns:1fr}
 .r2u-guide-featured-figure{margin:-2rem auto 2.5rem}
 .r2u-guide-prose{font-size:1rem;line-height:1.82}
 .r2u-guide-article-hero{padding-bottom:4rem}
}
@media(max-width:390px){
 .r2u-guides-hero h1{font-size:2.7rem}
 .r2u-guide-article-hero h1{font-size:2.35rem}
 .r2u-guide-card-img{padding:1rem}
 .r2u-guide-card-copy{padding:1.25rem}
 .r2u-guide-featured-figure{border-radius:10px;padding:.8rem}
 .r2u-guide-article-cta>a{max-width:100%;white-space:normal}
}
@media(prefers-reduced-motion:reduce){
 .r2u-guide-card{transition:none}
 .r2u-guide-card:hover{transform:none}
}