/* The Light Data — Blog / Articles stylesheet */
:root{
  --ink:#101a30;--ink2:#1b2a4a;--navy:#0d1729;--navy2:#132038;
  --teal:#0e9aa7;--teald:#0b7c86;--amber:#d98a1e;
  --paper:#fbfcfe;--grid:#e6ecf6;--line:#d7e0ef;
  --slate:#5c6b86;--slatel:#8493ac;--green:#1f9d63;--red:#d1495b;
  --radius:14px;--shadow:0 16px 44px rgba(12,22,44,.10);
  --nav-h:64px;--maxw:820px;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{font-family:'Inter',system-ui,sans-serif;color:var(--ink);background:var(--paper);line-height:1.65;-webkit-font-smoothing:antialiased}
a{color:var(--teald);text-decoration:none}
a:hover{text-decoration:underline}
img{max-width:100%}

/* ---------- nav ---------- */
.nav{position:sticky;top:0;z-index:50;height:var(--nav-h);display:flex;align-items:center;overflow-x:auto;
  background:rgba(251,252,254,.9);backdrop-filter:blur(10px);border-bottom:1px solid var(--line)}
.nav::-webkit-scrollbar{height:0}
.nav-in{max-width:1120px;width:100%;margin:0 auto;padding:0 22px;display:flex;align-items:center;gap:18px;min-width:max-content}
.brand{display:flex;align-items:center;gap:11px;flex:0 0 auto}
.brand img{width:38px;height:38px;object-fit:contain}
.brand b{font-family:'Space Grotesk',sans-serif;font-size:17px;color:var(--ink);letter-spacing:.2px}
.brand span{display:block;font-size:9.5px;color:var(--slatel);letter-spacing:1.3px;text-transform:uppercase;margin-top:1px}
.nav-menu{display:flex;gap:3px;align-items:center;margin-left:auto;flex:0 0 auto}
.nav-menu a{padding:7px 12px;border-radius:8px;font-size:13.5px;font-weight:600;color:var(--ink2);white-space:nowrap}
.nav-menu a:hover{background:rgba(14,154,167,.1);color:var(--teald);text-decoration:none}
.nav-menu a.active{background:var(--teald);color:#fff}

/* ---------- article hero (dark gradient band) ---------- */
.art-hero{position:relative;overflow:hidden;color:#fff;
  background:linear-gradient(120deg,var(--teald) 0%,#0a6d76 45%,var(--navy) 100%);
  padding:56px 22px 60px}
.art-hero::before{content:"";position:absolute;width:520px;height:520px;border-radius:50%;top:-220px;right:-120px;
  background:radial-gradient(circle,rgba(255,255,255,.14),transparent 70%)}
.art-hero::after{content:"";position:absolute;inset:0;background-image:radial-gradient(rgba(255,255,255,.09) 1px,transparent 1px);background-size:26px 26px;opacity:.5}
.hero-in{max-width:var(--maxw);margin:0 auto;position:relative}
.chip{display:inline-flex;align-items:center;gap:7px;font-size:12px;font-weight:700;letter-spacing:.5px;text-transform:uppercase;
  color:#fff;background:rgba(255,255,255,.16);border:1px solid rgba(255,255,255,.28);padding:5px 13px;border-radius:100px}
.art-hero h1{font-family:'Space Grotesk',sans-serif;font-size:38px;line-height:1.12;letter-spacing:-.6px;margin:16px 0 0}
.art-hero .lede{margin-top:16px;font-size:18px;line-height:1.55;color:rgba(255,255,255,.9);max-width:660px}
.art-hero .meta{margin-top:20px;display:flex;flex-wrap:wrap;gap:8px 18px;font-size:13px;color:rgba(255,255,255,.8)}
.art-hero .meta b{color:#fff}
@media(max-width:640px){.art-hero h1{font-size:29px}.art-hero .lede{font-size:16px}}

/* ---------- article body ---------- */
.art-body{max-width:var(--maxw);margin:0 auto;padding:44px 22px 30px;font-size:16.5px}
.art-body h2{font-family:'Space Grotesk',sans-serif;font-size:26px;color:var(--ink);letter-spacing:-.3px;margin:38px 0 12px;padding-top:8px;scroll-margin-top:80px}
.art-body h2 .n{display:inline-flex;align-items:center;justify-content:center;width:32px;height:32px;border-radius:9px;background:var(--teald);color:#fff;font-size:15px;margin-right:11px;vertical-align:3px}
.art-body h3{font-family:'Space Grotesk',sans-serif;font-size:19.5px;color:var(--ink2);margin:26px 0 8px}
.art-body h3 a{color:var(--ink2)}
.art-body p{margin:12px 0;color:#2a3852}
.art-body .lead{font-size:18px;color:var(--slate);line-height:1.6}
.art-body ul,.art-body ol{margin:12px 0 12px 4px;padding-left:22px;color:#2a3852}
.art-body li{margin:7px 0}
.art-body ul li::marker{color:var(--teal)}
.art-body strong{color:var(--ink)}
.art-body hr{border:none;border-top:1px solid var(--line);margin:34px 0}

/* table of contents */
.toc{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:18px 22px;margin:6px 0 8px;box-shadow:0 6px 20px rgba(12,22,44,.04)}
.toc .t{font-family:'Space Grotesk',sans-serif;font-weight:700;font-size:13px;color:var(--slatel);letter-spacing:1.5px;text-transform:uppercase;margin-bottom:10px}
.toc ol{margin:0;padding-left:20px;columns:2;column-gap:26px}
.toc li{margin:5px 0;font-size:14.5px}
.toc a{color:var(--ink2);font-weight:500}
@media(max-width:640px){.toc ol{columns:1}}

/* tables */
.tbl-wrap{overflow-x:auto;margin:16px 0}
table{width:100%;border-collapse:collapse;font-size:15px;background:#fff;border:1px solid var(--line);border-radius:12px;overflow:hidden}
thead th{background:var(--teald);color:#fff;text-align:left;padding:11px 14px;font-weight:600;font-size:14px}
tbody td{padding:10px 14px;border-top:1px solid var(--grid);color:var(--ink2)}
tbody tr:nth-child(even){background:#f6f9fc}
td.mono,th.mono{font-family:'IBM Plex Mono',monospace}
.tbl-red thead th:first-child{background:var(--red)}
.tbl-red thead th:last-child{background:var(--green)}

/* callouts */
.callout{border-radius:var(--radius);padding:16px 20px;margin:18px 0;border:1px solid var(--line);background:#fff;font-size:15.5px}
.callout .c-t{font-weight:700;color:var(--ink);margin-bottom:4px;display:flex;align-items:center;gap:8px}
.callout.note{background:rgba(14,154,167,.06);border-color:rgba(14,154,167,.28)}
.callout.note .c-t{color:var(--teald)}
.callout.tip{background:rgba(31,157,99,.07);border-color:rgba(31,157,99,.3)}
.callout.tip .c-t{color:var(--green)}
.callout.warn{background:rgba(217,138,30,.08);border-color:rgba(217,138,30,.34)}
.callout.warn .c-t{color:#a5670f}

/* example box */
.example{border:1px solid var(--line);border-left:4px solid var(--amber);border-radius:12px;background:#fffdf8;padding:16px 20px;margin:18px 0}
.example .e-t{font-size:12px;font-weight:700;letter-spacing:1px;text-transform:uppercase;color:var(--amber);margin-bottom:8px}
.example p{margin:6px 0}

/* threshold list */
.thr{list-style:none;margin:14px 0;padding:0}
.thr li{display:flex;align-items:flex-start;gap:11px;margin:9px 0;padding-left:0}
.thr .dot{width:13px;height:13px;border-radius:50%;flex:0 0 auto;margin-top:5px}
.thr .good{background:var(--green)}.thr .ok{background:var(--amber)}.thr .bad{background:var(--red)}.thr .info{background:var(--teald)}
.thr b{color:var(--ink)}

/* key takeaways */
.keyt{background:linear-gradient(135deg,#0e9aa7,#0b7c86);color:#fff;border-radius:18px;padding:24px 26px;margin:30px 0}
.keyt .k-t{font-family:'Space Grotesk',sans-serif;font-size:18px;font-weight:700;margin-bottom:12px;display:flex;align-items:center;gap:9px}
.keyt ul{list-style:none;margin:0;padding:0}
.keyt li{position:relative;padding-left:26px;margin:9px 0;color:rgba(255,255,255,.94);font-size:15.5px}
.keyt li::before{content:"✓";position:absolute;left:0;font-weight:800;color:#bfeef2}

/* cross-link cards */
.xlink{display:flex;align-items:center;gap:16px;border:1px solid var(--line);border-radius:var(--radius);padding:18px 20px;margin:16px 0;background:#fff;transition:.15s}
.xlink:hover{border-color:var(--teal);box-shadow:var(--shadow);text-decoration:none;transform:translateY(-2px)}
.xlink .ic{width:46px;height:46px;flex:0 0 auto;border-radius:12px;background:linear-gradient(135deg,var(--teal),var(--teald));color:#fff;display:flex;align-items:center;justify-content:center;font-size:20px}
.xlink .xt{flex:1}
.xlink .xt .k{font-size:11px;font-weight:700;letter-spacing:.6px;text-transform:uppercase;color:var(--slatel)}
.xlink .xt .h{font-family:'Space Grotesk',sans-serif;font-weight:700;font-size:16.5px;color:var(--ink);margin-top:2px}
.xlink .xt .d{font-size:13.5px;color:var(--slate);margin-top:3px}
.xlink .arw{color:var(--teal);font-size:22px;flex:0 0 auto}
.xlink-grid{display:grid;gap:14px}

/* chips row */
.chiprow{display:flex;flex-wrap:wrap;gap:9px;margin:14px 0}
.pill{font-family:'IBM Plex Mono',monospace;font-size:13px;font-weight:600;color:var(--teald);background:rgba(14,154,167,.09);border:1px solid rgba(14,154,167,.24);padding:6px 13px;border-radius:100px}

/* feature grid */
.fgrid{display:grid;grid-template-columns:1fr 1fr;gap:14px;margin:16px 0}
@media(max-width:640px){.fgrid{grid-template-columns:1fr}}
.fcard{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:18px}
.fcard h4{font-family:'Space Grotesk',sans-serif;font-size:16px;color:var(--teald);margin-bottom:6px}
.fcard p,.fcard ul{font-size:14.5px;color:var(--slate);margin:0}
.fcard ul{padding-left:18px}

/* ---------- index / blog home ---------- */
.home-hero{background:linear-gradient(120deg,var(--teald),#0a6d76 48%,var(--navy));color:#fff;padding:64px 22px 66px;text-align:center;position:relative;overflow:hidden}
.home-hero::after{content:"";position:absolute;inset:0;background-image:radial-gradient(rgba(255,255,255,.09) 1px,transparent 1px);background-size:26px 26px;opacity:.5}
.home-hero .in{max-width:760px;margin:0 auto;position:relative}
.home-hero h1{font-family:'Space Grotesk',sans-serif;font-size:40px;letter-spacing:-.6px;line-height:1.12}
.home-hero p{margin-top:16px;font-size:17.5px;color:rgba(255,255,255,.9)}
.home-wrap{max-width:1080px;margin:0 auto;padding:40px 22px 60px}
.sec-h{font-family:'Space Grotesk',sans-serif;font-size:14px;letter-spacing:2px;text-transform:uppercase;color:var(--slatel);text-align:center}
.sec-lead{text-align:center;font-family:'Space Grotesk',sans-serif;font-weight:700;font-size:26px;color:var(--ink);margin:6px 0 26px}
.cardgrid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
@media(max-width:860px){.cardgrid{grid-template-columns:1fr 1fr}}
@media(max-width:560px){.cardgrid{grid-template-columns:1fr}}
.acard{display:flex;flex-direction:column;background:#fff;border:1px solid var(--line);border-radius:18px;overflow:hidden;transition:.16s;box-shadow:0 8px 24px rgba(12,22,44,.05)}
.acard:hover{transform:translateY(-4px);box-shadow:var(--shadow);text-decoration:none;border-color:var(--teal)}
.acard .top{height:96px;background:linear-gradient(120deg,var(--teal),var(--teald));position:relative;overflow:hidden}
.acard .top.amber{background:linear-gradient(120deg,var(--amber),#c2740f)}
.acard .top.navy{background:linear-gradient(120deg,var(--navy2),var(--teald))}
.acard .top::after{content:"";position:absolute;inset:0;background-image:radial-gradient(rgba(255,255,255,.14) 1px,transparent 1px);background-size:18px 18px}
.acard .top .ct{position:absolute;left:16px;bottom:12px;color:#fff;font-size:11px;font-weight:700;letter-spacing:.6px;text-transform:uppercase;background:rgba(0,0,0,.18);padding:4px 11px;border-radius:100px}
.acard .bd{padding:18px 20px 20px;display:flex;flex-direction:column;flex:1}
.acard h3{font-family:'Space Grotesk',sans-serif;font-size:18px;color:var(--ink);line-height:1.25}
.acard p{font-size:14px;color:var(--slate);margin:8px 0 16px;flex:1}
.acard .go{font-weight:700;font-size:14px;color:var(--teald)}

/* ---------- footer ---------- */
.foot{border-top:1px solid var(--line);background:#fff;padding:30px 22px;margin-top:20px}
.foot-in{max-width:1080px;margin:0 auto;display:flex;justify-content:space-between;align-items:center;gap:16px;flex-wrap:wrap;color:var(--slatel);font-size:13px}
.foot .fb{display:flex;align-items:center;gap:10px;color:var(--slate)}
.foot .fb img{width:26px;height:26px}
.foot .soc{display:flex;gap:10px}
.foot .soc a{width:34px;height:34px;border-radius:9px;display:flex;align-items:center;justify-content:center;background:#f2f6fb;border:1px solid var(--line);color:var(--slate)}
.foot .soc a:hover{color:var(--teald);border-color:var(--teal)}
.foot .soc svg{width:17px;height:17px}

/* ---------- path flow (menu path SPSS/AMOS) ---------- */
.pathflow{display:flex;flex-wrap:wrap;align-items:center;gap:8px;margin:14px 0}
.pathflow .st{background:rgba(14,154,167,.09);border:1px solid rgba(14,154,167,.28);color:var(--teald);font-weight:600;font-size:13.5px;padding:7px 12px;border-radius:9px;font-family:'IBM Plex Mono',monospace}
.pathflow .st.go{background:var(--teald);color:#fff;border-color:var(--teald)}
.pathflow .arw2{color:var(--slatel);font-weight:800}
/* how-to steps box */
.howto{border:1px solid var(--line);border-left:4px solid var(--teal);border-radius:12px;background:#f7fbfc;padding:14px 20px;margin:18px 0}
.howto .ht{font-size:12px;font-weight:700;letter-spacing:1px;text-transform:uppercase;color:var(--teald);margin-bottom:6px;display:flex;align-items:center;gap:7px}
.howto ol{margin:6px 0 4px;padding-left:20px}
.howto li{margin:5px 0;font-size:15px;color:#2a3852}
.howto li::marker{color:var(--teal);font-weight:700}
/* sub-note under example */
.art-body .src{font-size:13px;color:var(--slatel);font-style:italic;margin-top:-4px}