/* ProgramGeeks theme – mobile-first, CSS variables, dark default + light mode */
:root{--bg:#0d1326;--card:#141b33;--muted:#1b2340;--fg:#eef1f8;--mfg:#a5aecb;--border:#2a3458;--primary:#4f7cff;--accent:#8b5cf6;--ok:#34d399;--err:#f87171;--r:14px;
--grad:linear-gradient(120deg,var(--primary),var(--accent));--glow:0 0 40px -10px color-mix(in srgb,var(--primary) 60%,transparent);
--sans:"Space Grotesk",system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;--mono:"JetBrains Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace}
html.light{--bg:#f8f9fc;--card:#fff;--muted:#eef0f6;--fg:#1a2140;--mfg:#5a6384;--border:#dfe3ee}
*{box-sizing:border-box}html{scroll-behavior:smooth}
body{margin:0;background:var(--bg);color:var(--fg);font:16px/1.6 var(--sans)}
a{color:inherit;text-decoration:none}a:hover{color:var(--primary)}
img{max-width:100%;height:auto}
:focus-visible{outline:2px solid var(--primary);outline-offset:2px}
h1{font-size:clamp(2rem,5vw,3.6rem);line-height:1.1;margin:.2em 0}h2{font-size:clamp(1.5rem,3vw,2.2rem);margin:.3em 0 .8em}h3,.h3{font-size:1.05rem;margin:.4em 0}
.container{max-width:1240px;margin:0 auto;padding:0 1rem}.narrow{max-width:900px}.section{padding:3.5rem 1rem}.section-sm{margin:2rem 0}.center{text-align:center}
.screen-reader-text{position:absolute!important;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0)}
.skip-link{position:absolute;left:-999px}.skip-link:focus{left:1rem;top:1rem;z-index:99;background:var(--card);padding:.5rem 1rem}
.text-gradient{background:var(--grad);-webkit-background-clip:text;background-clip:text;color:transparent}
.mono{font-family:var(--mono)}.muted{color:var(--mfg)}.small{font-size:.8rem}.huge{font-size:6rem;margin:0;font-weight:700}
.eyebrow{font:500 .72rem var(--mono);text-transform:uppercase;letter-spacing:.12em;color:var(--primary);margin:0}
.lead{color:var(--mfg);font-size:1.1rem;max-width:620px}.meta{font-size:.8rem;color:var(--mfg)}
.btn,.btn-ghost{display:inline-flex;align-items:center;justify-content:center;gap:.4rem;border-radius:9px;padding:.55rem 1rem;font:600 .9rem var(--sans);cursor:pointer;border:1px solid var(--border)}
.btn{background:var(--grad);color:#fff;border:0}.btn-ghost{background:var(--muted);color:var(--fg)}.btn-ghost:hover{border-color:var(--primary)}.btn.block{display:flex;margin-top:1rem}
.field{width:100%;background:var(--bg);color:var(--fg);border:1px solid var(--border);border-radius:9px;padding:.6rem .8rem;font:.88rem var(--mono)}.field.big{height:3rem;font-size:1rem;margin-top:1rem}
textarea.field{min-height:200px;resize:vertical}
.card{display:block;background:var(--card);border:1px solid var(--border);border-radius:var(--r);padding:1.25rem;transition:transform .2s,border-color .2s,box-shadow .2s}
.lift:hover{transform:translateY(-3px);border-color:var(--primary);box-shadow:var(--glow)}
.grid{display:grid;gap:1rem}.row{display:flex;flex-wrap:wrap;gap:.5rem;align-items:center}.row-between{display:flex;justify-content:space-between;align-items:center}
@media(min-width:640px){.g2,.g3,.g4,.g5{grid-template-columns:repeat(2,1fr)}}
@media(min-width:1000px){.g3{grid-template-columns:repeat(3,1fr)}.g4{grid-template-columns:repeat(4,1fr)}.g5{grid-template-columns:repeat(5,1fr)}}
.chips{display:flex;flex-wrap:wrap;gap:.5rem;margin:1rem 0}.chip{border:1px solid var(--border);border-radius:99px;padding:.25rem .8rem;font:.75rem var(--mono);background:transparent;color:var(--fg);cursor:pointer}.chip.active,.chip:hover{border-color:var(--primary);color:var(--primary)}
.pill{display:inline-block;border:1px solid var(--border);border-radius:99px;padding:.2rem .8rem;font:.75rem var(--mono);color:var(--mfg)}
/* header */
.site-header{position:sticky;top:0;z-index:50;background:color-mix(in srgb,var(--bg) 85%,transparent);backdrop-filter:blur(10px);border-bottom:1px solid var(--border)}
.header-inner{display:flex;align-items:center;justify-content:space-between;gap:1rem;height:64px}
.logo{display:flex;align-items:center;gap:.5rem;font-weight:700}.logo-mark{display:grid;place-items:center;width:32px;height:32px;border-radius:8px;background:var(--grad);color:#fff;font:600 .75rem var(--mono)}
.main-nav{display:none}.main-nav .menu{display:flex;list-style:none;margin:0;padding:0;gap:.25rem}.main-nav a{padding:.5rem .75rem;font-size:.9rem;display:block}
.main-nav.open{display:block;position:absolute;top:64px;left:0;right:0;background:var(--card);padding:1rem;border-bottom:1px solid var(--border)}.main-nav.open .menu{flex-direction:column}
.mega{position:relative}.mega-panel{display:none;position:absolute;left:0;top:100%;width:520px;grid-template-columns:1fr 1fr;gap:.2rem;background:var(--card);border:1px solid var(--border);border-radius:var(--r);padding:.75rem;box-shadow:var(--glow)}
.mega:hover .mega-panel,.mega:focus-within .mega-panel{display:grid}.mega-panel a{border-radius:8px}.mega-panel a:hover{background:var(--muted)}
.header-actions{display:flex;gap:.5rem;align-items:center}.header-actions .search-form{display:none}
.search-form{display:flex;gap:.4rem}
@media(min-width:900px){.main-nav{display:flex;align-items:center}.nav-toggle{display:none}.header-actions .search-form{display:flex;width:200px}}
/* hero */
.hero{position:relative;overflow:hidden}.grid-bg{position:absolute;inset:0;z-index:-1;opacity:.4;background-image:linear-gradient(var(--border) 1px,transparent 1px),linear-gradient(90deg,var(--border) 1px,transparent 1px);background-size:48px 48px;-webkit-mask-image:radial-gradient(ellipse at top,#000 30%,transparent 75%);mask-image:radial-gradient(ellipse at top,#000 30%,transparent 75%)}
.hero-grid{display:grid;gap:2.5rem;padding:4rem 1rem;align-items:center}@media(min-width:900px){.hero-grid{grid-template-columns:1fr 1fr}}
.hero-search{display:flex;gap:.5rem;margin-top:2rem}.hero-search input{flex:1;height:3rem;background:var(--bg);color:var(--fg);border:1px solid var(--border);border-radius:9px;padding:0 1rem;font:1rem var(--mono)}
.hero-img{border-radius:20px;border:1px solid var(--border);box-shadow:var(--glow)}
.cat{display:flex;gap:1rem;align-items:center}.icon{display:grid;place-items:center;width:48px;height:48px;border-radius:10px;background:var(--grad);color:#fff;font:700 1rem var(--mono);flex-shrink:0}
.stats{display:grid;grid-template-columns:repeat(2,1fr);gap:1rem;background:var(--grad);color:#fff;border-radius:20px;padding:2rem;text-align:center}.stats>div{display:flex;flex-direction:column}.stat-num{font:700 2.4rem var(--mono)}
@media(min-width:800px){.stats{grid-template-columns:repeat(4,1fr)}}
.plan .price{font:700 2rem var(--mono);margin:.3rem 0}.plan ul{list-style:none;padding:0;color:var(--mfg)}.plan.featured{border-color:var(--primary);box-shadow:var(--glow)}
.faq details{border-bottom:1px solid var(--border);padding:1rem 0}.faq details:last-child{border:0}.faq summary{cursor:pointer;font-weight:600}
.newsletter{display:grid;gap:1.5rem;align-items:center;padding:2rem}@media(min-width:800px){.newsletter{grid-template-columns:1fr 1fr}}.newsletter form .field{flex:1}
.success{color:var(--ok)}
/* games */
.game pre{background:var(--muted);padding:.8rem;border-radius:9px;font:.85rem var(--mono);white-space:pre-wrap}.game .field{flex:1}
.robot-grid{display:grid;grid-template-columns:repeat(5,36px);gap:4px;margin:.75rem 0}.robot-grid div{width:36px;height:36px;border-radius:6px;background:var(--muted);display:grid;place-items:center}.robot-grid .wall{background:color-mix(in srgb,var(--err) 60%,transparent)}
/* blog */
.with-sidebar{display:grid;gap:2rem;margin-top:1.5rem}@media(min-width:1000px){.with-sidebar{grid-template-columns:1fr 300px}}
.sidebar .widget{margin-bottom:1rem}.sidebar ul{padding-left:1rem;color:var(--mfg)}.widget-title{margin-top:0}
.featured-post{background:var(--grad);color:#fff;margin-bottom:1.5rem;padding:2rem}.featured-post .eyebrow{color:#fff}
.post-card .thumb img{border-radius:10px;margin-bottom:.6rem}
.breadcrumbs ol{display:flex;flex-wrap:wrap;gap:.5rem;list-style:none;padding:0;margin:0 0 1.5rem;font-size:.85rem;color:var(--mfg)}.breadcrumbs li+li:before{content:"/";margin-right:.5rem}
.toc{margin:1.5rem 0}.toc ol{margin:0;padding-left:1.2rem}
.prose{line-height:1.8}.prose p,.prose li{color:var(--mfg)}.prose h2{margin-top:2rem}.prose code{font-family:var(--mono);background:var(--muted);padding:.1rem .35rem;border-radius:4px}.prose pre{background:var(--muted);padding:1rem;border-radius:9px;overflow:auto}
.author-box{display:flex;gap:1rem;align-items:center;margin:2rem 0}.author-box img{border-radius:50%}
.share{display:flex;gap:.8rem;margin:1.5rem 0;color:var(--mfg)}.share a{color:var(--primary)}
.nav-links{display:flex;justify-content:space-between;gap:1rem;margin:1.5rem 0}.nav-links a{color:var(--primary)}
.pagination .nav-links{justify-content:center}.page-numbers{padding:.4rem .8rem;border:1px solid var(--border);border-radius:8px}.page-numbers.current{background:var(--grad);color:#fff;border:0}
.comment-list{list-style:none;padding:0}.comment-body{border:1px solid var(--border);border-radius:var(--r);padding:1rem;margin-bottom:1rem}
.comment-form input:not([type=submit]):not([type=checkbox]),.comment-form textarea{width:100%;background:var(--bg);color:var(--fg);border:1px solid var(--border);border-radius:9px;padding:.6rem}
/* tools */
.tool-ui{margin:1.5rem 0 3rem;display:grid;gap:.75rem}.tool-ui .stats-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(130px,1fr));gap:.5rem}
.tool-ui .stat{border:1px solid var(--border);border-radius:10px;padding:.75rem}.tool-ui .stat b{display:block;font:700 1.5rem var(--mono)}
.diff-add{color:var(--ok)}.diff-del{color:var(--err)}.diff-eq{color:var(--mfg)}
.two{display:grid;gap:.75rem}@media(min-width:800px){.two{grid-template-columns:1fr 1fr}}
.preview{border:1px solid var(--border);border-radius:9px;padding:1rem;overflow:auto}
/* footer */
.site-footer{margin-top:5rem;background:var(--card);border-top:1px solid var(--border)}.footer-grid{display:grid;gap:2rem;padding:3.5rem 1rem}@media(min-width:800px){.footer-grid{grid-template-columns:1.4fr 1fr 1fr 1fr}}
.site-footer ul{list-style:none;padding:0;margin:0}.site-footer li{margin:.4rem 0;font-size:.9rem;color:var(--mfg)}.social{display:flex;gap:1rem}
.copyright{text-align:center;border-top:1px solid var(--border);padding:1.5rem;margin:0;font-size:.8rem;color:var(--mfg)}
@media(prefers-reduced-motion:reduce){*{transition:none!important;scroll-behavior:auto!important}}