/* ==========================================================================
   Loop Engineering - style.css
   Design system: "engineering brutalism with typographic discipline"
   No gradients. No shadows. No border-radius. Orange <= 10% of surface.
   ========================================================================== */

:root {
  --paper: #F7F5F0;
  --ink: #141412;
  --ember: #E84E0F;
  --ember-deep: #B33A08;
  --graphite: #5C5A54;
  --grid: #E2DFD6;

  --bg: var(--paper);
  --fg: var(--ink);
  --accent: var(--ember);
  --accent-text: var(--ember-deep); /* orange text on light bg (WCAG AA) */
  --meta: var(--graphite);
  --line: var(--grid);
  --code-bg: #131210;
  --code-fg: #EDEAE2;
  --code-meta: #8A8780;
  --code-line: #2A2825;
}

html.dark {
  --bg: #131210;
  --fg: #EDEAE2;
  --accent: #FF6B1A;
  --accent-text: #FF6B1A;
  --meta: #8A8780;
  --line: #2A2825;
}

/* ---------- base ---------- */

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: 1.125rem;           /* 18px */
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  padding-bottom: 8rem;
}

::selection { background: var(--accent); color: var(--bg); }

.font-sans { font-family: 'Space Grotesk', system-ui, sans-serif; }
.font-mono { font-family: 'JetBrains Mono', ui-monospace, monospace; }

a { color: inherit; }

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

.sr-only {
  position: absolute; width: 1px; height: 1px;
  padding: 0; margin: -1px; overflow: hidden;
  clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}

.wrap {
  max-width: 64rem;              /* ~1024px */
  margin: 0 auto;
  padding: 0 1rem;
}
@media (min-width: 768px) { .wrap { padding: 0 2rem; } }

/* ---------- header ---------- */

.site-header { padding: 3rem 0 2rem; }

.site-header .bar {
  display: flex; flex-direction: column; gap: 2rem;
  align-items: flex-start; justify-content: space-between;
}
@media (min-width: 768px) {
  .site-header .bar { flex-direction: row; align-items: flex-end; gap: 1rem; }
}

.logo {
  display: flex; align-items: center; gap: .75rem;
  text-decoration: none; width: fit-content;
}
.logo svg { width: 2.5rem; height: 2rem; color: var(--accent); flex-shrink: 0; }
.logo .wordmark {
  font-family: 'Space Grotesk', system-ui, sans-serif;
  font-weight: 700; text-transform: uppercase;
  font-size: 1.5rem; letter-spacing: -0.02em;
  line-height: 1; white-space: nowrap; color: var(--fg);
}
@media (min-width: 768px) { .logo .wordmark { font-size: 1.875rem; } }

/* logo loop draws itself once on load */
.logo .loop-path {
  stroke-dasharray: 200; stroke-dashoffset: 200;
  animation: drawLoop .8s cubic-bezier(.2,0,0,1) .1s forwards;
}
@keyframes drawLoop { to { stroke-dashoffset: 0; } }
@media (prefers-reduced-motion: reduce) {
  .logo .loop-path { animation: none; stroke-dashoffset: 0; }
}

.site-nav {
  font-family: 'JetBrains Mono', monospace; font-size: .875rem;
  display: flex; flex-wrap: wrap; gap: 1rem 2rem;
}
.site-nav a, .site-nav button {
  text-decoration: none; color: var(--fg);
  background: none; border: 0; padding: 0; font: inherit; cursor: pointer;
}
.site-nav a:hover, .site-nav button:hover {
  text-decoration: underline;
  text-decoration-color: var(--accent);
  text-decoration-thickness: 2px; text-underline-offset: 4px;
}
.site-nav a[aria-current="page"] { color: var(--accent-text); }
.site-nav .rss { color: var(--accent-text); }
.site-nav .theme-toggle { color: var(--meta); }
.site-nav .theme-toggle:hover { color: var(--fg); }
html.dark .toggle-dark { display: none; }
html:not(.dark) .toggle-light { display: none; }

/* ---------- hero (homepage) ---------- */

.eyebrow {
  font-family: 'JetBrains Mono', monospace; font-size: .875rem;
  color: var(--meta); margin: 0 0 1.5rem;
}

.hero h1 {
  font-family: 'Space Grotesk', system-ui, sans-serif;
  font-weight: 600;
  font-size: clamp(2.5rem, 11vw, 6rem);
  letter-spacing: -0.04em; line-height: .95;
  margin: 0 0 2rem;
}

.hero .intro {
  max-width: 68ch; font-size: 1.125rem; margin: 0 0 4rem;
}
@media (min-width: 768px) { .hero .intro { font-size: 1.25rem; } }

.rule { height: 2px; background: var(--line); border: 0; margin: 0 0 4rem; }

/* ---------- featured post ---------- */

.featured { position: relative; margin-bottom: 6rem; }

.meta-line {
  font-family: 'JetBrains Mono', monospace;
  font-size: .75rem; color: var(--meta); margin: 0 0 1rem;
}
@media (min-width: 768px) { .meta-line { font-size: .875rem; } }

.featured h2 {
  font-family: 'Space Grotesk', system-ui, sans-serif;
  font-weight: 600; letter-spacing: -0.03em; line-height: 1.1;
  font-size: clamp(2.25rem, 6vw, 3.75rem);
  margin: 0 0 1.5rem;
}
.featured h2 a { text-decoration: none; }
.featured h2 a::before { content: ""; position: absolute; inset: 0; }
.featured:hover h2 { color: var(--accent-text); }

.featured .excerpt { max-width: 68ch; margin: 0 0 2rem; }

.readmore {
  position: relative; z-index: 1;
  font-family: 'JetBrains Mono', monospace;
  font-size: .875rem; font-weight: 700;
  text-transform: uppercase; letter-spacing: .1em;
  color: var(--accent-text); text-decoration: none;
}
.readmore:hover {
  text-decoration: underline;
  text-decoration-thickness: 2px; text-underline-offset: 4px;
}

/* ---------- dense index ---------- */

.index { border-top: 2px solid var(--line); margin-bottom: 3rem; }

.index-row {
  display: block; text-decoration: none;
  border-bottom: 2px solid var(--line);
  padding: 1rem 0;
}
.index-row .cols {
  display: flex; flex-direction: column; gap: .5rem; padding: 0 .5rem;
}
@media (min-width: 1024px) {
  .index-row .cols { flex-direction: row; align-items: baseline; gap: 1.5rem; }
}
.index-row .num {
  font-family: 'JetBrains Mono', monospace; font-size: .875rem;
  color: var(--meta); min-width: 5rem;
}
.index-row .title {
  font-family: 'Space Grotesk', system-ui, sans-serif;
  font-weight: 600; letter-spacing: -0.02em;
  font-size: 1.25rem; flex-grow: 1;
}
@media (min-width: 768px) { .index-row .title { font-size: 1.5rem; } }
.index-row .tags { display: flex; align-items: baseline; gap: 1rem; }
.index-row .tag, .index-row time {
  font-family: 'JetBrains Mono', monospace; font-size: .75rem;
  color: var(--meta); white-space: nowrap;
}
.index-row time { min-width: 5.5rem; text-align: right; }

.index-row:hover { background: var(--fg); color: var(--bg); }
.index-row:hover .num { color: var(--accent); }
.index-row:hover .tag, .index-row:hover time { color: inherit; }
.index-row:focus-visible { outline-offset: -2px; }

.archive-link { margin-bottom: 6rem; }
.archive-link a {
  font-family: 'JetBrains Mono', monospace;
  font-size: .875rem; font-weight: 700;
  text-transform: uppercase; letter-spacing: .1em;
  color: var(--accent-text); text-decoration: none;
}
.archive-link a:hover {
  text-decoration: underline;
  text-decoration-thickness: 2px; text-underline-offset: 4px;
}

/* ---------- newsletter ---------- */

.newsletter {
  border: 2px solid var(--fg);
  padding: 1.5rem; max-width: 68ch;
}
@media (min-width: 768px) { .newsletter { padding: 2rem; } }

.newsletter h3 {
  font-family: 'JetBrains Mono', monospace;
  font-size: 1.25rem; font-weight: 700;
  text-transform: uppercase; letter-spacing: -0.01em;
  margin: 0 0 1rem;
}
.newsletter p { margin: 0 0 2rem; }

.newsletter form {
  display: flex; flex-direction: column; gap: 1rem; align-items: flex-end;
}
@media (min-width: 640px) { .newsletter form { flex-direction: row; } }

.newsletter .field { flex-grow: 1; width: 100%; }
.newsletter input[type="email"] {
  width: 100%; background: transparent;
  border: 0; border-bottom: 2px solid var(--fg);
  font-family: 'JetBrains Mono', monospace; font-size: .875rem;
  padding: .5rem 0; color: var(--fg); border-radius: 0;
}
.newsletter input[type="email"]::placeholder { color: var(--meta); }
.newsletter input[type="email"]:focus {
  outline: none; border-bottom-color: var(--accent);
}
.newsletter button {
  width: 100%; cursor: pointer;
  background: var(--fg); color: var(--bg);
  font-family: 'JetBrains Mono', monospace;
  font-size: .875rem; font-weight: 700;
  text-transform: uppercase; letter-spacing: .1em;
  padding: .75rem 1.5rem; border: 2px solid transparent; border-radius: 0;
}
@media (min-width: 640px) { .newsletter button { width: auto; } }
.newsletter button:hover { background: var(--accent); color: var(--paper); }
html.dark .newsletter button:hover { color: #131210; }
.newsletter .form-note {
  font-family: 'JetBrains Mono', monospace; font-size: .75rem;
  color: var(--accent-text); margin: 1rem 0 0;
}

/* ---------- footer ---------- */

.site-footer {
  margin-top: 8rem; border-top: 2px solid var(--line); padding-top: 2rem;
}
.site-footer .bar {
  display: flex; flex-direction: column; gap: 1rem;
  align-items: center; justify-content: space-between;
  font-family: 'JetBrains Mono', monospace;
  font-size: .75rem; color: var(--meta);
}
@media (min-width: 768px) { .site-footer .bar { flex-direction: row; } }
.site-footer p { margin: 0; }
.site-footer .links { display: flex; gap: 1.5rem; }
.site-footer a { text-decoration: none; }
.site-footer a:hover {
  text-decoration: underline; text-decoration-color: var(--accent);
}

/* ---------- archive page ---------- */

.archive-title {
  font-family: 'Space Grotesk', system-ui, sans-serif;
  font-weight: 600; text-transform: uppercase;
  letter-spacing: -0.04em; line-height: 1;
  font-size: clamp(3rem, 8vw, 4.5rem);
  margin: 0 0 .5rem;
}
.archive-count {
  font-family: 'JetBrains Mono', monospace; font-size: .875rem;
  color: var(--meta); margin: 0 0 3rem;
}

.filters { display: flex; flex-wrap: wrap; gap: .75rem; margin-bottom: 4rem; }
.filters button {
  font-family: 'JetBrains Mono', monospace; font-size: .75rem;
  text-transform: uppercase; cursor: pointer;
  padding: .25rem .75rem; background: none; border-radius: 0;
  border: 2px solid transparent; color: var(--meta);
}
.filters button:hover { border-color: var(--fg); color: var(--fg); }
.filters button[aria-pressed="true"] {
  border-color: var(--accent); color: var(--accent-text);
}

.year-group { margin-bottom: 5rem; }
.year-head { display: flex; align-items: center; gap: 1.5rem; margin-bottom: 1.5rem; }
.year-head h2 {
  font-family: 'Space Grotesk', system-ui, sans-serif;
  font-weight: 600; letter-spacing: -0.02em;
  font-size: 1.875rem; margin: 0;
}
@media (min-width: 768px) { .year-head h2 { font-size: 2.25rem; } }
.year-head .line { height: 2px; background: var(--line); flex-grow: 1; }

.index-row[hidden] { display: none; }

/* ---------- blog post ---------- */

.progress {
  position: fixed; top: 0; left: 0; right: 0; height: 2px;
  z-index: 50; pointer-events: none;
}
.progress .bar-line {
  height: 2px; width: 0%; background: var(--accent);
}
.progress .bar-loop {
  position: absolute; right: .5rem; top: 0;
  width: 2rem; height: 2rem; color: var(--accent);
  opacity: 0; transition: opacity .2s;
}
.progress .bar-loop.visible { opacity: 1; }
@media (prefers-reduced-motion: reduce) {
  .progress .bar-loop { transition: none; }
}

.crumb { margin-bottom: 3rem; }
.crumb a {
  font-family: 'JetBrains Mono', monospace;
  font-size: .75rem; text-transform: uppercase; letter-spacing: .1em;
  color: var(--meta); text-decoration: none;
}
@media (min-width: 768px) { .crumb a { font-size: .875rem; } }
.crumb a:hover {
  text-decoration: underline;
  text-decoration-color: var(--accent);
  text-decoration-thickness: 2px; text-underline-offset: 4px;
}

.post { max-width: 68ch; }

.post-header { margin-bottom: 3rem; }
.post-header .meta-line { margin-bottom: 1.5rem; }
.post-header h1 {
  font-family: 'Space Grotesk', system-ui, sans-serif;
  font-weight: 600; letter-spacing: -0.03em; line-height: 1.1;
  font-size: clamp(2.5rem, 7vw, 3.75rem);
  margin: 0 0 1.5rem;
}
.post-header .subtitle {
  font-style: italic; font-size: 1.25rem; line-height: 1.4;
  color: var(--meta); margin: 0;
}
@media (min-width: 768px) { .post-header .subtitle { font-size: 1.5rem; } }

.loop-divider {
  display: flex; align-items: center;
  color: var(--accent); margin-bottom: 3rem;
}
.loop-divider .line { height: 2px; background: currentColor; flex-grow: 1; }
.loop-divider svg { width: 2rem; height: 2rem; flex-shrink: 0; margin-left: -2px; }

.prose p { margin: 0 0 1.5rem; }
.prose h2 {
  font-family: 'Space Grotesk', system-ui, sans-serif;
  font-weight: 600; letter-spacing: -0.02em;
  font-size: 1.875rem; margin: 4rem 0 1.5rem;
}
.prose h3 {
  font-family: 'Space Grotesk', system-ui, sans-serif;
  font-weight: 600; font-size: 1.375rem; margin: 3rem 0 1rem;
}
.prose h2 .anchor, .prose h3 .anchor {
  margin-left: .75rem; opacity: 0;
  color: var(--accent); text-decoration: none;
}
.prose h2:hover .anchor, .prose h3:hover .anchor,
.prose .anchor:focus-visible { opacity: 1; }

.prose a {
  text-decoration: underline;
  text-decoration-color: var(--accent);
  text-decoration-thickness: 2px; text-underline-offset: 4px;
}
.prose a:hover { background: var(--fg); color: var(--bg); }

.prose blockquote {
  border-left: 2px solid var(--accent);
  margin: 2.5rem 0; padding-left: 1.5rem;
  font-style: italic; font-size: 1.25rem; line-height: 1.4;
  color: var(--meta);
}
@media (min-width: 768px) { .prose blockquote { font-size: 1.5rem; } }
.prose blockquote p { margin: 0; }

.prose ul, .prose ol { margin: 0 0 1.5rem; padding-left: 1.5rem; }
.prose li { margin-bottom: .5rem; }

.prose code {
  font-family: 'JetBrains Mono', monospace; font-size: .875em;
  background: var(--line); padding: .1em .35em;
}

/* code blocks */
.codeblock {
  background: var(--code-bg);
  border-left: 2px solid var(--accent);
  margin: 2.5rem 0;
}
.codeblock .codebar {
  display: flex; justify-content: space-between; align-items: center;
  padding: .5rem 1rem; border-bottom: 2px solid var(--code-line);
}
.codeblock .lang {
  font-family: 'JetBrains Mono', monospace;
  font-size: .75rem; color: var(--code-meta);
}
.codeblock .copy-btn {
  display: flex; align-items: center; gap: .5rem; cursor: pointer;
  font-family: 'JetBrains Mono', monospace; font-size: .75rem;
  color: var(--code-meta); background: none; border: 0; padding: 0;
}
.codeblock .copy-btn:hover { color: var(--code-fg); }
.codeblock .copy-btn:focus-visible { color: var(--accent); outline: none; }
.codeblock pre {
  margin: 0; padding: 1rem; overflow-x: auto;
  font-family: 'JetBrains Mono', monospace;
  font-size: .875rem; line-height: 1.6; color: var(--code-fg);
}
.codeblock pre code { background: none; padding: 0; font-size: 1em; }
.codeblock ::selection { background: #FF6B1A; color: #131210; }

/* figures */
.prose figure { margin: 3rem 0; }
.prose figure .frame {
  border: 2px solid var(--fg); padding: .5rem; background: var(--bg);
}
.prose figure img, .prose figure .frame > svg,
.prose figure .diagram { width: 100%; display: block; }
.prose figcaption {
  font-family: 'JetBrains Mono', monospace;
  font-size: .75rem; color: var(--meta); margin-top: .75rem;
}

/* tables */
.prose table {
  border-collapse: collapse; width: 100%; margin: 2.5rem 0;
  font-size: 1rem;
}
.prose th {
  font-family: 'JetBrains Mono', monospace; font-size: .75rem;
  text-transform: uppercase; text-align: left; color: var(--meta);
}
.prose th, .prose td {
  border: 1px solid var(--line); padding: .5rem .75rem;
}

/* post footer nav */
.post-nav {
  display: grid; grid-template-columns: 1fr 1fr;
  border-top: 2px solid var(--line);
  font-family: 'JetBrains Mono', monospace; font-size: .875rem;
}
.post-nav a, .post-nav .disabled { display: block; padding: 1rem; }
.post-nav a {
  text-decoration: none; border-right: 2px solid var(--line);
}
.post-nav a:hover { background: var(--fg); color: var(--bg); }
.post-nav a:focus-visible { outline-offset: -2px; }
.post-nav .disabled {
  color: var(--meta); text-align: right;
  cursor: not-allowed; user-select: none;
}
.post-nav .next { text-align: right; border-right: 0; border-left: 2px solid var(--line); margin-left: -2px; }

.post .newsletter { margin: 4rem 0; max-width: none; }

/* ---------- simple pages ---------- */
.page-body { max-width: 68ch; }
.page-body h1 {
  font-family: 'Space Grotesk', system-ui, sans-serif;
  font-weight: 600; letter-spacing: -0.03em;
  font-size: clamp(2.5rem, 7vw, 3.75rem); margin: 0 0 2rem;
}

.site-footer .devby { display: inline-flex; align-items: center; gap: .5rem; }
.site-footer .devby img { height: .875rem; width: auto; display: block; }
html.dark .site-footer .devby img { filter: brightness(0) invert(1); }
.site-footer .devby a:hover img { opacity: .7; }

.site-footer .bar { gap: 1.5rem; }