/* ==========================================================================
   LowCostPC.co.uk — Tech Optimization Hub
   Global stylesheet. Mobile-first, dependency-free, fast-loading.
   ========================================================================== */

:root{
  --navy:#0b1e2d;
  --navy-2:#122c40;
  --teal:#0f8b8d;
  --teal-light:#14b8bb;
  --lime:#8bd450;
  --lime-dark:#6fb437;
  --ink:#152230;
  --ink-soft:#3f5364;
  --paper:#f6f9fa;
  --paper-2:#eef3f4;
  --white:#ffffff;
  --border:#dde6e9;
  --radius:10px;
  --shadow:0 2px 10px rgba(11,30,45,0.08);
  --shadow-lg:0 12px 30px rgba(11,30,45,0.14);
  --maxw:1180px;
  --font:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
}

*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{
  margin:0;
  font-family:var(--font);
  color:var(--ink);
  background:var(--paper);
  line-height:1.65;
  font-size:16px;
}
img{max-width:100%;display:block;height:auto}
a{color:var(--teal);text-decoration:none}
a:hover{color:var(--lime-dark);text-decoration:underline}
h1,h2,h3,h4{line-height:1.25;color:var(--navy);font-weight:800;letter-spacing:-0.01em}
h1{font-size:clamp(1.7rem,4vw,2.6rem);margin:0 0 .5em}
h2{font-size:clamp(1.3rem,2.6vw,1.7rem);margin:1.6em 0 .6em}
h3{font-size:1.15rem;margin:1.4em 0 .5em}
p{margin:0 0 1.1em}
ul,ol{margin:0 0 1.1em;padding-left:1.3em}
li{margin-bottom:.4em}
code,kbd{background:#eef3f4;border:1px solid var(--border);border-radius:4px;padding:.1em .4em;font-size:.9em;font-family:Consolas,Menlo,monospace}
blockquote{margin:1.4em 0;padding:.8em 1.2em;border-left:4px solid var(--lime);background:var(--paper-2);border-radius:0 8px 8px 0;color:var(--ink-soft)}
hr{border:none;border-top:1px solid var(--border);margin:2em 0}
.container{max-width:var(--maxw);margin:0 auto;padding:0 20px}
.visually-hidden{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}

/* Skip link */
.skip-link{position:absolute;left:-999px;top:0;background:var(--navy);color:#fff;padding:.6em 1em;z-index:200;border-radius:0 0 8px 0}
.skip-link:focus{left:0}

/* ---------------- Header / Nav ---------------- */
.site-header{
  background:var(--navy);
  position:sticky;top:0;z-index:100;
  box-shadow:0 1px 0 rgba(255,255,255,0.06);
}
.header-inner{
  display:flex;align-items:center;justify-content:space-between;
  max-width:var(--maxw);margin:0 auto;padding:12px 20px;gap:12px;
}
.brand{display:flex;align-items:center;gap:10px;color:#fff;text-decoration:none}
.brand:hover{text-decoration:none;color:#fff}
.brand svg{width:36px;height:36px;flex:none}
.brand-text{display:flex;flex-direction:column;line-height:1.1}
.brand-text strong{font-size:1.05rem;font-weight:800;letter-spacing:-.01em}
.brand-text span{font-size:.68rem;color:var(--lime);text-transform:uppercase;letter-spacing:.08em;font-weight:600}

.nav-toggle{
  display:inline-flex;align-items:center;justify-content:center;
  background:transparent;border:1px solid rgba(255,255,255,.25);border-radius:8px;
  width:42px;height:38px;color:#fff;cursor:pointer;
}
.nav-toggle svg{width:20px;height:20px}

.main-nav{
  display:none;
  position:absolute;left:0;right:0;top:100%;
  background:var(--navy-2);
  border-top:1px solid rgba(255,255,255,.08);
}
.main-nav.open{display:block}
.main-nav ul{list-style:none;margin:0;padding:8px 20px 16px;display:flex;flex-direction:column;max-width:var(--maxw);margin:0 auto}
.main-nav a{
  display:block;color:#dfeef0;padding:.7em .2em;border-bottom:1px solid rgba(255,255,255,.06);
  font-weight:600;font-size:.95rem;
}
.main-nav a:hover,.main-nav a.active{color:var(--lime)}

@media (min-width:900px){
  .nav-toggle{display:none}
  .main-nav{display:block;position:static;background:transparent;border-top:none}
  .main-nav ul{flex-direction:row;padding:0;gap:22px;justify-content:flex-end}
  .main-nav a{border-bottom:none;padding:.3em 0;position:relative}
  .main-nav a.active::after,.main-nav a:hover::after{
    content:"";position:absolute;left:0;right:0;bottom:-6px;height:2px;background:var(--lime);
  }
}

/* ---------------- Hero ---------------- */
.hero{
  background:linear-gradient(150deg,var(--navy) 0%,var(--navy-2) 55%,#0d3446 100%);
  color:#fff;padding:52px 0 60px;
}
.hero .container{display:grid;gap:28px}
.hero h1{color:#fff;margin-bottom:.4em}
.hero p.lead{color:#cfe3e6;font-size:1.1rem;max-width:60ch;margin-bottom:1.4em}
.hero-badges{display:flex;flex-wrap:wrap;gap:10px;margin-top:1em}
.badge{
  background:rgba(255,255,255,.08);border:1px solid rgba(255,255,255,.18);
  color:#e7f4f1;padding:.4em .9em;border-radius:999px;font-size:.82rem;font-weight:600;
}
.hero-cta{display:flex;flex-wrap:wrap;gap:12px}

.btn{
  display:inline-block;padding:.75em 1.3em;border-radius:8px;font-weight:700;
  text-decoration:none;border:2px solid transparent;transition:transform .1s ease;
}
.btn:hover{text-decoration:none}
.btn-primary{background:var(--lime);color:var(--navy)}
.btn-primary:hover{background:var(--lime-dark);color:var(--navy)}
.btn-outline{border-color:rgba(255,255,255,.4);color:#fff}
.btn-outline:hover{border-color:#fff;color:#fff;background:rgba(255,255,255,.08)}
.btn-teal{background:var(--teal);color:#fff}
.btn-teal:hover{background:var(--teal-light);color:#fff}

/* ---------------- Sections grid on homepage ---------------- */
.section-strip{padding:56px 0}
.section-strip h2{text-align:center;margin-bottom:.2em}
.section-strip .subtitle{text-align:center;color:var(--ink-soft);max-width:60ch;margin:0 auto 2.2em}

.cat-grid{display:grid;gap:20px;grid-template-columns:1fr}
@media (min-width:700px){.cat-grid{grid-template-columns:repeat(2,1fr)}}
@media (min-width:1050px){.cat-grid{grid-template-columns:repeat(3,1fr)}}

.cat-card{
  background:#fff;border:1px solid var(--border);border-radius:var(--radius);
  padding:22px;box-shadow:var(--shadow);display:flex;flex-direction:column;gap:10px;
  transition:transform .15s ease, box-shadow .15s ease;
}
.cat-card:hover{transform:translateY(-3px);box-shadow:var(--shadow-lg)}
.cat-card .icon{font-size:1.8rem}
.cat-card h3{margin:.1em 0 0}
.cat-card p{color:var(--ink-soft);margin-bottom:.4em;font-size:.95rem}
.cat-card a.card-link{font-weight:700;color:var(--teal)}
.cat-card ul.sub-list{list-style:none;padding:0;margin:0 0 .6em;font-size:.85rem;color:var(--ink-soft)}
.cat-card ul.sub-list li{margin-bottom:.25em;padding-left:1.1em;position:relative}
.cat-card ul.sub-list li::before{content:"›";position:absolute;left:0;color:var(--lime-dark);font-weight:800}

/* ---------------- Article list / index pages ---------------- */
.page-hero{background:var(--paper-2);border-bottom:1px solid var(--border);padding:36px 0}
.breadcrumb{font-size:.85rem;color:var(--ink-soft);margin-bottom:.8em}
.breadcrumb a{color:var(--ink-soft)}
.breadcrumb a:hover{color:var(--teal)}

.subsection-block{margin:2.4em 0}
.subsection-block h2{border-bottom:2px solid var(--paper-2);padding-bottom:.3em}
.article-grid{display:grid;gap:18px;grid-template-columns:1fr}
@media (min-width:760px){.article-grid{grid-template-columns:repeat(3,1fr)}}

.article-card{
  background:#fff;border:1px solid var(--border);border-radius:var(--radius);
  padding:18px;display:flex;flex-direction:column;gap:8px;box-shadow:var(--shadow);
}
.article-card h3{margin:0;font-size:1.02rem}
.article-card h3 a{color:var(--navy)}
.article-card p{color:var(--ink-soft);font-size:.9rem;margin-bottom:.3em}
.article-card .read-more{font-size:.85rem;font-weight:700}

/* ---------------- Article page ---------------- */
.article-wrap{padding:36px 0 60px}
.article-header{max-width:75ch;margin:0 auto 1.6em}
.article-meta{display:flex;flex-wrap:wrap;gap:10px;font-size:.82rem;color:var(--ink-soft);margin-bottom:.6em}
.article-meta span{background:var(--paper-2);border-radius:999px;padding:.25em .8em}
.article-body{max-width:75ch;margin:0 auto}
.article-body h2{scroll-margin-top:80px}
.key-takeaway{
  background:#eefaf0;border:1px solid #cdeed3;border-radius:var(--radius);
  padding:16px 18px;margin:1.6em 0;
}
.key-takeaway strong{color:var(--lime-dark)}
.callout-tip{background:#eaf7f7;border-left:4px solid var(--teal);border-radius:0 8px 8px 0;padding:14px 18px;margin:1.6em 0}
.callout-warn{background:#fff6e9;border-left:4px solid #e0a327;border-radius:0 8px 8px 0;padding:14px 18px;margin:1.6em 0}
.steps{counter-reset:step}
.steps > li{list-style:none;position:relative;padding-left:2.2em;margin-bottom:1em}
.steps > li::before{
  counter-increment:step;content:counter(step);
  position:absolute;left:0;top:0;background:var(--teal);color:#fff;
  width:1.6em;height:1.6em;border-radius:50%;display:flex;align-items:center;justify-content:center;
  font-size:.85rem;font-weight:700;
}
table{width:100%;border-collapse:collapse;margin:1.4em 0;font-size:.92rem}
table caption{text-align:left;color:var(--ink-soft);margin-bottom:.4em;font-size:.85rem}
th,td{border:1px solid var(--border);padding:.55em .7em;text-align:left}
th{background:var(--paper-2)}

.related-box{
  max-width:75ch;margin:2.6em auto 0;background:var(--paper-2);border-radius:var(--radius);padding:20px;
}
.related-box h2{margin-top:0;font-size:1.1rem}
.related-box ul{margin:0;padding-left:1.2em}

.faq dt{font-weight:700;color:var(--navy);margin-top:1em}
.faq dd{margin:.3em 0 0;color:var(--ink-soft)}

/* ---------------- CTA band ---------------- */
.cta-band{background:var(--navy);color:#fff;padding:44px 0;text-align:center}
.cta-band h2{color:#fff}
.cta-band p{color:#cfe3e6;max-width:55ch;margin:0 auto 1.2em}

/* ---------------- Contact ---------------- */
.contact-wrap{padding:40px 0 60px;display:grid;gap:32px}
@media (min-width:800px){.contact-wrap{grid-template-columns:1fr 1fr}}
.contact-form{background:#fff;border:1px solid var(--border);border-radius:var(--radius);padding:24px;box-shadow:var(--shadow)}
.form-row{margin-bottom:16px}
.form-row label{display:block;font-weight:700;margin-bottom:.4em;font-size:.9rem}
.form-row input,.form-row textarea,.form-row select{
  width:100%;padding:.7em .8em;border:1px solid var(--border);border-radius:8px;font:inherit;background:#fcfdfd;
}
.form-row input:focus,.form-row textarea:focus{outline:2px solid var(--teal-light);outline-offset:1px}
.form-note{font-size:.8rem;color:var(--ink-soft)}
.hp-field{position:absolute !important;left:-9999px !important;top:-9999px !important;width:1px;height:1px;overflow:hidden}

/* ---------------- Footer ---------------- */
.site-footer{background:var(--navy);color:#c9dbdd;padding:44px 0 26px;margin-top:40px}
.footer-grid{display:grid;gap:28px;grid-template-columns:1fr}
@media (min-width:760px){.footer-grid{grid-template-columns:2fr 1fr 1fr 1fr}}
.footer-grid h4{color:#fff;font-size:.92rem;margin:0 0 .8em;text-transform:uppercase;letter-spacing:.06em}
.footer-grid ul{list-style:none;padding:0;margin:0}
.footer-grid li{margin-bottom:.5em;font-size:.88rem}
.footer-grid a{color:#c9dbdd}
.footer-grid a:hover{color:var(--lime)}
.footer-brand p{color:#9db3b6;font-size:.88rem;max-width:40ch}
.footer-bottom{
  border-top:1px solid rgba(255,255,255,.1);margin-top:30px;padding-top:18px;
  display:flex;flex-wrap:wrap;gap:10px;justify-content:space-between;font-size:.8rem;color:#9db3b6;
}

/* ---------------- Utility ---------------- */
.center{text-align:center}
.mt-0{margin-top:0}