/* Excel Keys brand layer for LearnLab public pages. Matches excelkeys.in (dashfolio theme). Loaded after landing.css. */
:root{--ink:#080c24;--ink-2:#0e1433;--ink-3:#171f4a;--ink-line:rgba(255,255,255,.1);--on-ink:#e8edf7;--on-ink-muted:#aab5ca;--brand:#3b5bdb;--brand-2:#7b9bff;--brand-deep:#2a41b0;--brand-soft:#e9eeff;--grad:linear-gradient(100deg,#8fb0ff 0%,#38bdf8 50%,#a78bfa 100%);--btn-a:#5b7cfa;--btn-b:#2f4bd0;--text:#0f172a;--muted:#4a556b;--line:#e3e8f0;--tint:#f4f7f9}
body.ek{background:#fff;color:var(--text);font-size:16px}
body.ek ::selection{background:var(--brand-2);color:var(--ink)}
.ek a:focus-visible,.ek button:focus-visible,.ek summary:focus-visible{outline:3px solid var(--brand-2)}
.ek .kicker{color:var(--brand-deep);font-family:ui-monospace,"SFMono-Regular",Consolas,monospace;letter-spacing:.14em}
.ek .kicker:before{background:var(--brand);box-shadow:0 0 0 4px rgba(59,91,219,.15)}
/* Header: identical idea to excelkeys.in */
.ek-header-wrap{position:sticky;top:0;z-index:40;background:rgba(8,12,36,.96);border-bottom:1px solid var(--ink-line);backdrop-filter:none}
.ek-header{max-width:1250px;margin:auto;height:72px;padding:0 24px;display:flex;align-items:center;gap:18px;color:#fff}
.ek-brand{display:inline-flex;align-items:center;gap:11px;flex:none}
.ek-brand img{width:40px;height:40px;border-radius:11px;box-shadow:0 6px 18px -6px rgba(59,91,219,.8)}
.ek-word{font-weight:800;font-size:19px;letter-spacing:.06em;color:#fff;white-space:nowrap}
.ek-word b{color:var(--brand-2);font-weight:800}
.ek-chip{display:inline-flex;align-items:center;padding:5px 11px;border-radius:999px;border:1px solid rgba(123,155,255,.45);background:rgba(123,155,255,.12);color:#cdd8ff;font-size:12px;font-weight:700;letter-spacing:.04em}
.ek-nav{margin-left:auto;display:flex;align-items:center;gap:2px}
.ek-nav a{padding:10px 13px;border-radius:10px;font-weight:600;font-size:15px;color:rgba(255,255,255,.78);position:relative}
.ek-nav a:hover,.ek-nav a[aria-current]{color:#fff}
.ek-nav a[aria-current]:after{content:"";position:absolute;left:13px;right:13px;bottom:3px;height:2px;border-radius:2px;background:var(--brand-2)}
.ek-nav .ek-cta{margin-left:14px;padding:11px 18px;border-radius:999px;color:#fff;background:linear-gradient(135deg,var(--btn-a),var(--btn-b));box-shadow:0 10px 28px -10px rgba(59,91,219,.7),inset 0 1px 0 rgba(255,255,255,.35);white-space:nowrap}
.ek-toggle{display:none;margin-left:auto;width:46px;height:46px;border-radius:12px;border:1px solid var(--ink-line);background:rgba(255,255,255,.05);place-items:center;padding:0}
.ek-toggle i{display:block;width:20px;height:2px;margin:4px auto;border-radius:2px;background:#fff;transition:transform .3s,opacity .2s}
.ek-nav-open .ek-toggle i:nth-child(1){transform:translateY(6px) rotate(45deg)}.ek-nav-open .ek-toggle i:nth-child(2){opacity:0}.ek-nav-open .ek-toggle i:nth-child(3){transform:translateY(-6px) rotate(-45deg)}
.ek-subnav{background:#fff;border-bottom:1px solid var(--line)}
.ek-subnav div{max-width:1250px;margin:auto;padding:0 24px;display:flex;gap:4px;overflow-x:auto;scrollbar-width:none}
.ek-subnav div::-webkit-scrollbar{display:none}
.ek-subnav a{padding:12px 12px;font-size:14px;font-weight:600;color:var(--muted);white-space:nowrap}
.ek-subnav a:hover{color:var(--brand-deep)}
html{scroll-padding-top:130px}
/* Buttons in Excel Keys style */
.ek .button{border-radius:999px;font-size:15px;padding:14px 24px;gap:10px;background:linear-gradient(135deg,var(--btn-a),var(--btn-b));border-color:transparent;box-shadow:0 10px 28px -12px rgba(59,91,219,.7)}
.ek .button.light{background:#fff;color:var(--brand-deep);border:1px solid #cfd7e3;box-shadow:none}
.ek .button.dark{background:var(--ink);border-color:var(--ink)}
.ek .button.white{background:#fff;color:var(--brand-deep)}
.ek .button.sql{background:linear-gradient(135deg,#14a38a,#0f766e)}
.ek .small-button{font-size:14px;padding:11px 18px}
/* Dark hero like the main site */
.ek .hero-section{background:radial-gradient(60% 70% at 85% 10%,rgba(124,58,237,.35),transparent 60%),radial-gradient(50% 60% at 10% 90%,rgba(34,211,238,.18),transparent 60%),radial-gradient(70% 80% at 30% 20%,rgba(59,91,219,.45),transparent 65%),var(--ink);color:#fff;padding:70px 0 60px}
.ek .hero-copy h1{color:#fff}
.ek .hero-copy h1 em{background:var(--grad);-webkit-background-clip:text;background-clip:text;color:transparent}
.ek .hero-copy p{color:var(--on-ink-muted);font-size:18px;max-width:520px}
.ek .hero-section .kicker{color:#cdd8ff}
.ek .hero-section .kicker:before{background:#7b9bff}
.ek .hero-section .button.light{background:rgba(255,255,255,.06);color:#fff;border-color:rgba(255,255,255,.25)}
.ek .tiny-trust{color:var(--on-ink-muted);font-size:14px}
.ek .hero-bottom{border-top-color:var(--ink-line);color:var(--on-ink-muted)}
.ek .hero-bottom b,.ek .hero-bottom strong{color:#fff}
.ek .art-grid{opacity:.12}.ek .orbit{border-color:rgba(255,255,255,.12)}
.ek-founder{display:inline-flex;align-items:center;gap:12px;margin-top:26px;padding:7px 18px 7px 7px;border-radius:999px;border:1px solid var(--ink-line);background:rgba(255,255,255,.06);color:#fff;max-width:100%}
.ek-founder img{width:44px;height:44px;border-radius:50%;object-fit:cover;box-shadow:0 0 0 2px var(--brand-2);flex:none}
.ek-founder span{display:grid;line-height:1.3}.ek-founder b{font-size:15px}.ek-founder small{font-size:13px;color:var(--on-ink-muted)}
/* Syllabus top band */
.ek .course-intro{padding:56px 0 20px}
.ek .course-intro p{font-size:17px;color:var(--muted);max-width:720px}
/* Readability on guides */
.ek .guide-wrap{font-size:17px}
.ek .guide-intro,.ek .guide-wrap p,.ek .guide-wrap li{color:#334155;line-height:1.75}
.ek .guide-breadcrumb,.ek .guide-byline{font-size:14px;color:var(--muted)}
.ek .guide-note{font-size:14px!important;color:var(--muted)!important}
.ek .guide-code{font-size:15px}
/* Certificate section */
.ek-cert-section{background:var(--tint)}
.ek-cert-grid{display:grid;grid-template-columns:1fr 1.15fr;gap:48px;align-items:center}
.ek-cert-grid h2{font-size:clamp(30px,4vw,44px);line-height:1.12;letter-spacing:-.03em;margin:14px 0}
.ek-cert-grid p{font-size:17px;color:var(--muted)}
.ek-ticks{list-style:none;padding:0;margin:20px 0 26px;display:grid;gap:10px}
.ek-ticks li{padding-left:30px;position:relative;font-size:16px;font-weight:600}
.ek-ticks li:before{content:"✓";position:absolute;left:0;top:0;width:22px;height:22px;border-radius:50%;display:grid;place-items:center;font-size:12px;color:#fff;background:var(--brand)}
.ek-cert-figure{margin:0;border-radius:18px;overflow:hidden;box-shadow:0 2px 4px rgba(15,23,42,.05),0 32px 64px -24px rgba(15,23,42,.35);transform:rotate(1.2deg)}
.ek-cert-figure img{display:block;width:100%;height:auto}
/* Business cross-sell band + footer (same look as excelkeys.in) */
.ek-band{background:linear-gradient(120deg,var(--ink) 0%,#1b2363 60%,#2a1f6b 100%);color:#fff;padding:56px 0;margin-top:40px}
.ek-band-inner{display:flex;align-items:center;justify-content:space-between;gap:32px;flex-wrap:wrap}
.ek-band h2{font-size:clamp(26px,3.4vw,38px);letter-spacing:-.02em;margin:10px 0}
.ek-band p{color:var(--on-ink-muted);max-width:620px;font-size:16px;margin:0}
.ek-kicker{font-family:ui-monospace,Consolas,monospace;font-size:12px;font-weight:700;letter-spacing:.14em;color:#cdd8ff}
.ek-band-actions{display:flex;gap:12px;flex-wrap:wrap}
.ek-btn{display:inline-flex;align-items:center;padding:14px 22px;border-radius:999px;font-weight:700;font-size:15px;color:#fff;background:linear-gradient(135deg,var(--btn-a),var(--btn-b));box-shadow:0 10px 28px -10px rgba(59,91,219,.7)}
.ek-btn-ghost{background:rgba(255,255,255,.05);border:1px solid rgba(255,255,255,.25);box-shadow:none}
.ek-footer{background:var(--ink);color:var(--on-ink-muted);font-size:15px;padding-top:56px}
.ek-foot-grid{display:grid;grid-template-columns:1.6fr 1fr 1fr 1fr;gap:40px;padding-bottom:40px}
.ek-foot-about p{margin:16px 0 0;max-width:30em;line-height:1.7}
.ek-footer h4{margin:0 0 14px;font-family:ui-monospace,Consolas,monospace;font-size:12px;letter-spacing:.14em;text-transform:uppercase;color:#fff}
.ek-footer .ek-foot-grid>div>a{display:block;padding:6px 0;color:var(--on-ink-muted)}
.ek-footer a:hover{color:#fff}
.ek-social{display:flex;flex-wrap:wrap;gap:8px;margin-top:18px}
.ek-social a{padding:8px 13px;border-radius:999px;border:1px solid var(--ink-line);font-size:13px;color:#cbd5e6}
.ek-foot-bottom{display:flex;justify-content:space-between;flex-wrap:wrap;gap:12px;padding:22px 28px 30px;border-top:1px solid var(--ink-line);font-size:14px}
.ek .site-footer,.ek .brand-community,.ek .about-band{display:none}
/* Responsive */
@media (max-width:1080px){.ek-nav a{padding:10px 9px;font-size:14px}.ek-foot-grid{grid-template-columns:1fr 1fr}.ek-foot-about{grid-column:1/-1}}
@media (max-width:920px){
 .ek-toggle{display:grid}
 .ek-nav{position:fixed;left:0;right:0;top:72px;height:calc(100vh - 72px);height:calc(100dvh - 72px);flex-direction:column;align-items:stretch;gap:0;padding:16px 20px 32px;background:var(--ink);overflow-y:auto;overscroll-behavior:contain;opacity:0;visibility:hidden;transform:translateY(-10px);transition:opacity .25s,transform .25s,visibility .25s}
 .ek-nav-open .ek-nav{opacity:1;visibility:visible;transform:none}
 .ek-nav a{font-size:19px;padding:15px 4px;border-bottom:1px solid var(--ink-line);border-radius:0}
 .ek-nav a[aria-current]:after{display:none}
 .ek-nav a[aria-current]{color:var(--brand-2)}
 .ek-nav .ek-cta{margin:20px 0 0;justify-content:center;text-align:center;border-bottom:0;border-radius:999px}
 body.ek-nav-open{overflow:hidden}
 .ek-cert-grid{grid-template-columns:minmax(0,1fr)}
 .ek-cert-figure{transform:none}
}
@media (max-width:640px){
 .ek-header{height:64px;padding:0 16px;gap:10px}.ek-nav{top:64px;height:calc(100dvh - 64px)}
 .ek-word{font-size:16px}.ek-brand img{width:36px;height:36px}
 .ek-chip{font-size:11px;padding:4px 9px}
 .ek-subnav div{padding:0 10px}
 .ek .hero-copy p{font-size:16px}
 .ek-foot-grid{grid-template-columns:1fr 1fr;gap:28px}
 .ek .button{width:auto}
 .ek-band-actions .ek-btn{width:100%;justify-content:center}
 .ek-founder small{font-size:12px}
}
@media (max-width:380px){.ek-chip{display:none}.ek-foot-grid{grid-template-columns:1fr}}
@media (prefers-reduced-motion:reduce){.ek-nav,.ek-toggle i{transition:none}}
.ek .tiny-trust{flex-wrap:wrap;row-gap:6px}.ek .tiny-trust span{white-space:nowrap}
/* 5.3: syllabus SEO sections, partner band and partner page */
.ek-syllabus-extra{display:grid;gap:56px;padding:24px 28px 40px}
.ek-syllabus-extra h2{font-size:clamp(24px,3vw,32px);letter-spacing:-.02em;line-height:1.2;margin:10px 0 16px}
.ek-two{display:grid;grid-template-columns:1fr 1fr;gap:40px}
.ek-list{margin:0;padding-left:22px;display:grid;gap:9px;font-size:16px;color:#334155;line-height:1.6}
.ek-steps ol{list-style:none;counter-reset:s;padding:0;margin:0;display:grid;grid-template-columns:repeat(4,1fr);gap:16px}
.ek-steps li{counter-increment:s;padding:20px;border:1px solid var(--line);border-radius:16px;background:#fff;font-size:15px;color:#334155;line-height:1.6}
.ek-steps li:before{content:counter(s,decimal-leading-zero);display:block;font:700 13px ui-monospace,Consolas,monospace;color:var(--brand);margin-bottom:8px}
.ek-steps li b{display:block;color:var(--text);margin-bottom:4px}
.ek-cert-mini{display:flex;align-items:center;justify-content:space-between;gap:28px;padding:32px;border-radius:20px;background:linear-gradient(120deg,#eef2ff,#f4f7f9);border:1px solid var(--line)}
.ek-cert-mini p{font-size:16px;color:var(--muted);max-width:640px;margin:0}
.ek-faq details{border-bottom:1px solid var(--line);padding:16px 0}
.ek-faq summary{cursor:pointer;font-weight:700;font-size:17px;list-style:none;display:flex;justify-content:space-between;gap:16px}
.ek-faq summary::-webkit-details-marker{display:none}
.ek-faq summary:after{content:"+";color:var(--brand);font-size:22px;line-height:1}
.ek-faq details[open] summary:after{content:"−"}
.ek-faq details p{margin:10px 0 0;font-size:16px;color:#334155;line-height:1.7}
.ek-partner-band{display:flex;align-items:center;justify-content:space-between;gap:28px;flex-wrap:wrap;margin:10px 0 30px;padding:36px;border-radius:20px;border:1px solid var(--line);background:#fff;box-shadow:0 12px 32px -16px rgba(15,23,42,.18)}
.ek-partner-band h2{font-size:clamp(24px,3vw,32px);letter-spacing:-.02em;margin:10px 0}
.ek-partner-band p{max-width:620px;color:var(--muted);font-size:16px;margin:0}
.ek-partner .hero-actions{margin:22px 0 10px}
.ek-partner-grid{display:grid;grid-template-columns:1fr 1fr;gap:14px}
.ek-partner-grid article{padding:18px;border:1px solid var(--line);border-radius:14px;background:#fff}
.ek-partner-grid h3{margin:0 0 6px;font-size:17px}
.ek-partner-grid p{margin:0;font-size:15px!important}
@media (max-width:900px){.ek-two{grid-template-columns:minmax(0,1fr)}.ek-steps ol{grid-template-columns:1fr 1fr}.ek-cert-mini{flex-direction:column;align-items:flex-start}}
@media (max-width:640px){.ek-syllabus-extra{padding:16px 16px 30px;gap:40px}.ek-steps ol,.ek-partner-grid{grid-template-columns:minmax(0,1fr)}.ek-partner-band{padding:24px}}
/* v5.7 readability: WCAG AA contrast for secondary text, footer headings as h2 */
.section-heading>p{color:#55607a}.steps p{color:#4f5a72}.step-number{color:#3d4a69}.demo-copy p{color:#4f5768}.feature-bullet small{color:#5a6070}.syllabus ol{color:#4d5670}
.guide-code code,.guide-section pre code{color:inherit}
.ek-footer h2.ek-fh{margin:0 0 14px;font-family:ui-monospace,Consolas,monospace;font-size:12px;letter-spacing:.14em;text-transform:uppercase;color:#fff;font-weight:700;line-height:1.4}
/* SQL practice page */
.px-actions{display:flex;flex-wrap:wrap;gap:12px;margin:22px 0}
.px-toc{display:flex;flex-wrap:wrap;gap:10px;margin:8px 0 26px}.px-toc a{padding:8px 14px;border:1px solid #d4d9e6;border-radius:999px;font-size:14px;font-weight:600;background:#fff;color:#14203e}.px-toc a:hover{border-color:#137766;color:#137766}
.px-ex{padding:20px 22px;margin:16px 0;border:1px solid #e1e5ee;border-radius:14px;background:#fff}
.px-ex h3{display:flex;gap:12px;align-items:flex-start;margin:0;font-size:17px;line-height:1.5;color:#14203e}
.px-num{flex:none;display:grid;place-items:center;width:30px;height:30px;border-radius:9px;background:#e3f3ef;color:#0f5f52;font-size:14px;font-weight:800}
.px-hi{margin:6px 0 10px 42px;color:#4f5768;font-size:15px}
.px-ex details{margin:8px 0 0 42px}.px-ex summary{cursor:pointer;font-weight:700;color:#294aca}
.px-hint p{margin:6px 0 0;color:#3d4a69}
.px-table{overflow-x:auto;margin:12px 0;border:1px solid #e1e5ee;border-radius:10px}
.px-table table{border-collapse:collapse;width:100%;font-size:14px}
.px-table th,.px-table td{padding:8px 12px;text-align:left;border-bottom:1px solid #eef0f5;white-space:nowrap}
.px-table th{background:#f4f6fa;font-weight:700;color:#14203e}.px-table td{color:#3d4a69}
@media(max-width:600px){.px-hi,.px-ex details{margin-left:0}.px-ex{padding:16px}}
.privacy-strip p{color:#454e63}.progress-demo small{color:#4f5768}#faq .reveal>p,#faq .section-heading p{color:#4f5768}
.px-hi{display:none}.show-hi .px-hi{display:block}.px-lang{cursor:pointer;font-family:inherit}
.px-out-label{margin:12px 0 4px;font-size:13px;font-weight:700;letter-spacing:.06em;text-transform:uppercase;color:#3d4a69}
.px-out{margin:0 0 14px;padding:14px 16px;border-radius:10px;background:#f4f6fa;border:1px solid #e1e5ee;color:#14203e;font:14px/1.7 ui-monospace,Consolas,monospace;white-space:pre-wrap;overflow-x:auto}
.px-ex .guide-code{white-space:pre;overflow-wrap:normal;overflow-x:auto;font-size:14px}