/* Blog McFly — Técnica / ingeniería (dirección A)
   Design system: design-system/mcfly/MASTER.md + pages/blog.md (Minimalism & Swiss Style · JetBrains Mono + IBM Plex Sans) */
:root{
  --bg:#F8FAFC;--surface:#FFFFFF;--fg:#1E293B;--fg-strong:#0F172A;--muted:#EAEFF3;--muted-fg:#475569;
  --primary:#475569;--accent:#2563EB;--on-accent:#FFFFFF;--accent-hover:#1D4ED8;--accent-tint:#EFF4FF;
  --border:#E2E8F0;--border-strong:#CBD5E1;--ring:#2563EB;
  --dark:#0F172A;--on-dark:#F8FAFC;--on-dark-muted:#CBD5E1;--on-dark-line:rgba(248,250,252,.08);
  --grid:rgba(71,85,105,.08);
  --mono:"JetBrains Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
  --sans:"IBM Plex Sans",ui-sans-serif,system-ui,-apple-system,"Segoe UI",sans-serif;
  --container:1160px;--gutter:20px;--t:160ms ease;
}
@media (min-width:768px){:root{--gutter:32px}}
@media (min-width:1440px){:root{--gutter:48px}}

*,*::before,*::after{box-sizing:border-box}
*{margin:0;padding:0}
html{-webkit-text-size-adjust:100%}
@media (prefers-reduced-motion:no-preference){html{scroll-behavior:smooth}}
body{background:var(--bg);color:var(--fg);font-family:var(--sans);font-size:16px;line-height:1.6;-webkit-font-smoothing:antialiased;
  min-height:100vh;min-height:100dvh;display:flex;flex-direction:column}
main{flex:1}
svg{display:block}
a{color:var(--accent);text-underline-offset:3px;text-decoration-thickness:1px;transition:color var(--t)}
a:hover{color:var(--accent-hover)}
:focus-visible{outline:2px solid var(--ring);outline-offset:3px}
h1,h2,h3{color:var(--fg-strong);text-wrap:balance;overflow-wrap:break-word;hyphens:auto}
p{text-wrap:pretty}
.wrap{width:100%;max-width:calc(var(--container) + 2*var(--gutter));margin:0 auto;padding:0 var(--gutter)}
.skip{position:absolute;left:16px;top:-80px;z-index:100;background:var(--dark);color:var(--on-dark);padding:12px 16px;font-family:var(--mono);font-size:14px;text-decoration:none}
.skip:focus{top:16px;color:var(--on-dark)}

/* Botones */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:10px;min-height:48px;padding:12px 20px;border:1px solid transparent;border-radius:2px;
  font-family:var(--mono);font-size:13px;font-weight:500;letter-spacing:.06em;text-transform:uppercase;text-decoration:none;cursor:pointer;
  transition:background-color var(--t),color var(--t),border-color var(--t)}
.btn svg{width:18px;height:18px;flex:none}
.btn-primary{background:var(--accent);color:var(--on-accent)}
.btn-primary:hover{background:var(--accent-hover);color:var(--on-accent)}
.btn-secondary{background:transparent;color:var(--fg-strong);border-color:var(--primary)}
.btn-secondary:hover{border-color:var(--fg-strong);color:var(--fg-strong)}

/* Header */
.site-head{background:var(--surface);border-bottom:1px solid var(--border-strong)}
.site-head .wrap{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:8px 24px;padding-top:10px;padding-bottom:10px}
.brand{display:inline-flex;align-items:center;gap:10px;min-height:44px;text-decoration:none;color:var(--fg-strong)}
.brand-mark{width:14px;height:14px;background:var(--accent);box-shadow:4px 4px 0 var(--border-strong)}
.brand b{font-family:var(--mono);font-weight:700;font-size:18px;letter-spacing:-.02em}
.site-nav{display:flex;align-items:center;flex-wrap:wrap;gap:8px 16px}
.site-nav ul{list-style:none;display:flex;gap:4px}
.site-nav ul a{display:inline-flex;align-items:center;min-height:44px;padding:0 12px;font-family:var(--mono);font-size:13px;letter-spacing:.06em;text-transform:uppercase;
  color:var(--muted-fg);text-decoration:none;border-bottom:2px solid transparent;transition:color var(--t),border-color var(--t)}
.site-nav ul a:hover{color:var(--fg-strong)}
.site-nav ul a[aria-current="page"]{color:var(--fg-strong);border-bottom-color:var(--accent)}
.site-nav .btn{min-height:44px;padding:10px 16px}

/* Hero: papel milimetrado + marcas de registro */
.hero{position:relative;border-bottom:1px solid var(--border-strong);
  background-color:var(--bg);
  background-image:linear-gradient(var(--grid) 1px,transparent 1px),linear-gradient(90deg,var(--grid) 1px,transparent 1px);
  background-size:24px 24px;background-position:-1px -1px}
.hero .wrap{position:relative;padding-top:64px;padding-bottom:56px}
.hero .wrap::before,.hero .wrap::after{content:"";position:absolute;width:16px;height:16px;border-color:var(--primary);border-style:solid}
.hero .wrap::before{top:24px;left:var(--gutter);border-width:1px 0 0 1px}
.hero .wrap::after{bottom:20px;right:var(--gutter);border-width:0 1px 1px 0}
.hero h1{display:inline-flex;align-items:flex-end;gap:.08em;font-family:var(--mono);font-weight:700;font-size:clamp(64px,13vw,148px);line-height:.9;letter-spacing:-.06em}
.hero h1::after{content:"";width:.42em;height:.12em;margin-bottom:.06em;background:var(--accent)}
.hero-lede{margin-top:20px;max-width:30em;font-size:clamp(18px,2.2vw,22px);line-height:1.5;color:var(--fg)}
@media (min-width:1024px){.hero .wrap{display:grid;grid-template-columns:1fr minmax(0,26em);align-items:end;gap:48px;padding-top:96px;padding-bottom:72px}
  .hero-lede{margin-top:0;padding-left:20px;border-left:2px solid var(--accent)}}

/* Listado */
.listing{padding:48px 0 80px}
.section-title{display:flex;align-items:center;gap:16px;margin-bottom:24px;font-family:var(--mono);font-size:13px;font-weight:500;letter-spacing:.1em;text-transform:uppercase;color:var(--muted-fg)}
.section-title::after{content:"";flex:1;height:1px;background:repeating-linear-gradient(90deg,var(--border-strong) 0 6px,transparent 6px 10px)}
.posts{list-style:none;display:grid;grid-template-columns:repeat(auto-fill,minmax(min(100%,320px),1fr));gap:24px}
@media (min-width:768px){.posts>.featured{grid-column:1/-1}}
.card{position:relative;display:grid;grid-template-columns:auto 1fr;gap:12px 16px;align-items:start;padding:24px;background:var(--surface);
  border:1px solid var(--border-strong);transition:border-color var(--t),box-shadow var(--t)}
.card:hover,.card:focus-within{border-color:var(--accent);box-shadow:inset 3px 0 0 var(--accent)}
.card>*{grid-column:2}
.card .num{grid-column:1;grid-row:1/span 2;font-family:var(--mono);font-size:13px;font-weight:700;color:var(--accent);padding:4px 8px;border:1px solid var(--accent)}
.card .tag{grid-row:1}
.card h3{font-size:clamp(21px,2.6vw,28px);line-height:1.25;font-weight:600;letter-spacing:-.01em}
.card h3 a{color:inherit;text-decoration:none}
.card h3 a::after{content:"";position:absolute;inset:0}
.card h3 a:focus-visible{outline:none}
.card h3 a:focus-visible::after{outline:2px solid var(--ring);outline-offset:3px}
.card:hover h3 a{text-decoration:underline}
.card .excerpt{max-width:44em;color:var(--fg)}
.card .meta{margin-top:4px}
.card .more{display:inline-flex;align-items:center;gap:8px;margin-top:4px;font-family:var(--mono);font-size:13px;font-weight:500;letter-spacing:.06em;text-transform:uppercase;color:var(--accent)}
.card .more svg{width:16px;height:16px}
@media (max-width:479px){.card{grid-template-columns:1fr}.card>*,.card .num{grid-column:1;grid-row:auto}.card .num{justify-self:start}}

.tag{display:inline-flex;align-items:center;justify-self:start;align-self:start;min-height:26px;padding:2px 8px;border:1px solid var(--border-strong);
  font-family:var(--mono);font-size:12px;font-weight:500;letter-spacing:.08em;text-transform:uppercase;color:var(--fg-strong);background:var(--muted)}

/* Meta como rótulo de plano */
.meta{display:grid;grid-template-columns:repeat(auto-fit,minmax(130px,max-content));border:1px solid var(--border-strong);background:var(--surface)}
.meta div{padding:8px 14px;border-right:1px solid var(--border-strong)}
.meta div:last-child{border-right:0}
.meta dt{font-family:var(--mono);font-size:11px;letter-spacing:.1em;text-transform:uppercase;color:var(--muted-fg)}
.meta dd{font-family:var(--mono);font-size:14px;color:var(--fg-strong)}
@media (max-width:479px){.meta{grid-template-columns:1fr 1fr}.meta div{border-right:0;border-bottom:1px solid var(--border-strong)}.meta div:nth-child(odd){border-right:1px solid var(--border-strong)}}

/* Artículo */
.post-head{background-color:var(--bg);background-image:linear-gradient(var(--grid) 1px,transparent 1px),linear-gradient(90deg,var(--grid) 1px,transparent 1px);
  background-size:24px 24px;border-bottom:1px solid var(--border-strong)}
.post-head .wrap{padding-top:24px;padding-bottom:40px;display:flex;flex-direction:column;align-items:flex-start}
.crumbs ol{list-style:none;display:flex;flex-wrap:wrap;align-items:center;gap:4px 10px;font-family:var(--mono);font-size:13px;color:var(--muted-fg)}
.crumbs li{display:inline-flex;align-items:center;gap:10px}
.crumbs li+li::before{content:"/";color:var(--border-strong)}
.crumbs a{display:inline-flex;align-items:center;min-height:32px}
.post-head .tag{margin-top:32px}
.post-head h1{margin-top:16px;max-width:20em;font-size:clamp(32px,5vw,54px);line-height:1.1;font-weight:600;letter-spacing:-.025em}
.post-head .lede{margin-top:16px;max-width:38em;font-size:clamp(17px,2vw,20px);line-height:1.6;color:var(--fg)}
.post-head .meta{margin-top:28px}

.post-body{background:var(--surface)}
.post-layout{display:grid;gap:32px;padding-top:48px;padding-bottom:80px}
@media (min-width:1024px){.post-layout{grid-template-columns:240px minmax(0,1fr);gap:64px;align-items:start}.toc{position:sticky;top:24px}}
.toc{border:1px solid var(--border-strong);padding:16px 20px}
.toc h2{font-family:var(--mono);font-size:12px;font-weight:500;letter-spacing:.1em;text-transform:uppercase;color:var(--muted-fg)}
.toc ol{list-style:none;margin-top:8px;counter-reset:toc}
.toc li{counter-increment:toc;border-top:1px dashed var(--border)}
.toc li:first-child{border-top:0}
.toc a{display:flex;gap:12px;align-items:baseline;padding:10px 0;min-height:44px;font-size:15px;line-height:1.4;color:var(--fg);text-decoration:none}
.toc a::before{content:counter(toc,decimal-leading-zero);font-family:var(--mono);font-size:12px;font-weight:700;color:var(--accent)}
.toc a:hover{color:var(--accent);text-decoration:underline}

.prose{max-width:68ch;font-size:17px;line-height:1.75;color:var(--fg);counter-reset:sec}
@media (min-width:768px){.prose{font-size:18px}}
.prose>*+*{margin-top:1.1em}
.prose h2{counter-increment:sec;display:flex;gap:14px;align-items:baseline;margin-top:2.4em;padding-top:16px;border-top:1px solid var(--border-strong);
  font-size:clamp(22px,2.6vw,28px);line-height:1.25;font-weight:600;letter-spacing:-.015em;scroll-margin-top:24px}
.prose h2::before{content:counter(sec,decimal-leading-zero);font-family:var(--mono);font-size:.55em;font-weight:700;color:var(--accent);transform:translateY(-.25em)}
.prose h3{margin-top:1.8em;font-family:var(--mono);font-size:15px;font-weight:700;letter-spacing:.04em;text-transform:uppercase}
.prose ul{list-style:none;padding-left:0}
.prose ul li{position:relative;padding-left:1.4em}
.prose ul li::before{content:"";position:absolute;left:0;top:.7em;width:7px;height:7px;background:var(--accent)}
.prose ol{padding-left:1.6em}
.prose ol li::marker{font-family:var(--mono);font-weight:700;color:var(--accent)}
.prose li+li{margin-top:.45em}
.prose strong{font-weight:600;color:var(--fg-strong)}
.prose blockquote{padding:4px 0 4px 20px;border-left:2px solid var(--fg-strong);font-size:1.06em;font-style:italic;color:var(--fg-strong)}

.note{display:grid;grid-template-columns:auto 1fr;gap:4px 12px;padding:16px 20px;background:var(--accent-tint);border:1px solid var(--accent);font-size:16px;line-height:1.65}
.note svg{width:20px;height:20px;color:var(--accent);grid-row:span 2;margin-top:2px}
.note-title{font-family:var(--mono);font-size:12px;font-weight:700;letter-spacing:.1em;text-transform:uppercase;color:var(--accent-hover)}
.note p{color:var(--fg)}

.table-wrap{overflow-x:auto;border:1px solid var(--border-strong);-webkit-overflow-scrolling:touch}
.compare{width:100%;min-width:520px;border-collapse:collapse;font-size:15px;line-height:1.5}
.compare caption{text-align:left;padding:12px 16px;border-bottom:1px solid var(--border-strong);font-family:var(--mono);font-size:12px;font-weight:500;letter-spacing:.08em;text-transform:uppercase;color:var(--muted-fg);background:var(--bg)}
.compare th,.compare td{padding:12px 16px;text-align:left;vertical-align:top;border-bottom:1px solid var(--border)}
.compare thead th{font-family:var(--mono);font-size:12px;font-weight:700;letter-spacing:.06em;text-transform:uppercase;color:var(--fg-strong);border-bottom:2px solid var(--fg-strong)}
.compare tbody th{font-weight:600;color:var(--fg-strong);width:30%}
.compare tbody tr:nth-child(even){background:var(--bg)}
.compare tbody tr:last-child>*{border-bottom:0}

/* Cierre */
.cta-band{padding:64px 0}
.cta-box{display:grid;gap:24px;align-items:center;padding:32px;background-color:var(--dark);color:var(--on-dark);
  background-image:linear-gradient(var(--on-dark-line) 1px,transparent 1px),linear-gradient(90deg,var(--on-dark-line) 1px,transparent 1px);background-size:24px 24px}
.cta-box h2{color:var(--on-dark);font-size:clamp(22px,2.8vw,30px);line-height:1.25;font-weight:600}
.cta-box p{margin-top:8px;color:var(--on-dark-muted);max-width:36em}
.cta-box :focus-visible{outline-color:var(--on-dark)}
.cta-actions{display:flex;flex-wrap:wrap;gap:12px}
.cta-box .btn-secondary{color:var(--on-dark);border-color:var(--on-dark-muted)}
.cta-box .btn-secondary:hover{background:var(--on-dark);color:var(--dark)}
@media (min-width:1024px){.cta-box{grid-template-columns:1fr auto;padding:48px 56px}}

/* Pie */
.site-foot{border-top:1px solid var(--border-strong);background:var(--surface);font-size:14px;color:var(--muted-fg)}
.site-foot .wrap{display:flex;flex-wrap:wrap;justify-content:space-between;align-items:center;gap:8px 32px;padding-top:24px;padding-bottom:24px}
.site-foot b{font-family:var(--mono);color:var(--fg-strong)}
.site-foot ul{list-style:none;display:flex;flex-wrap:wrap;gap:4px 20px}
.site-foot a{display:inline-flex;align-items:center;min-height:44px;font-family:var(--mono);font-size:13px}

@media (max-width:480px){.site-nav .btn .long{display:none}}
@media (prefers-reduced-motion:reduce){*,*::before,*::after{transition:none!important;animation:none!important;scroll-behavior:auto!important}}