@import url('https://fonts.googleapis.com/css2?family=Bricolage+Grotesque:opsz,wght@12..96,600;12..96,700;12..96,800&family=Instrument+Sans:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500&display=swap');

:root {
  --bg: #f6f7fb;
  --surface: #ffffff;
  --surface-alt: #f0f2f8;
  --ink: #101322;
  --muted: #566079;
  --line: #e1e4ef;
  --accent: #2f54eb;
  --accent-ink: #ffffff;
  --accent-soft: rgba(47, 84, 235, 0.08);
  --shadow: 0 30px 60px -30px rgba(16, 19, 34, 0.35);
  --code-bg: #181b2a;
  --code-ink: #e2e8f0;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0e1019;
    --surface: #161926;
    --surface-alt: #1c2032;
    --ink: #eef0f8;
    --muted: #9aa3ba;
    --line: #262b3d;
    --accent: #6c8bff;
    --accent-ink: #0e1019;
    --accent-soft: rgba(108, 139, 255, 0.12);
    --shadow: 0 30px 60px -30px #000000;
    --code-bg: #090b12;
    --code-ink: #eef0f8;
  }
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 17px/1.7 "Instrument Sans", system-ui, sans-serif;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 {
  font-family: "Bricolage Grotesque", "Instrument Sans", system-ui, sans-serif;
  line-height: 1.2;
  letter-spacing: -0.02em;
  color: var(--ink);
  margin: 0;
}

a {
  color: inherit;
  text-decoration: none;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

.wrap {
  width: min(1120px, 100% - 2.5rem);
  margin-inline: auto;
}

.reading-wrap {
  width: min(760px, 100% - 2.5rem);
  margin-inline: auto;
}

/* Header & Nav */
header.top {
  position: sticky;
  top: 0;
  z-index: 100;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line);
}

.bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  font: 700 1.2rem "Bricolage Grotesque", sans-serif;
  text-decoration: none;
}

.brand img {
  width: 32px;
  height: 32px;
  border-radius: 8px;
}

nav ul {
  display: flex;
  gap: 1.6rem;
  list-style: none;
  margin: 0;
  padding: 0;
  align-items: center;
}

nav a {
  color: var(--muted);
  font-weight: 500;
  font-size: 0.95rem;
  transition: color 0.15s;
}

nav a:hover, nav a.active {
  color: var(--ink);
}

.menu {
  display: none;
  background: none;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: var(--ink);
  padding: 0.4rem 0.75rem;
  font: inherit;
  cursor: pointer;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.65rem 1.15rem;
  border-radius: 10px;
  font-weight: 600;
  font-size: 0.95rem;
  border: 1px solid var(--line);
  background: var(--surface);
  transition: transform 0.15s, border-color 0.15s;
}

.btn:hover {
  transform: translateY(-2px);
}

.btn.primary {
  background: var(--accent);
  color: var(--accent-ink);
  border-color: var(--accent);
}

.btn.secondary {
  background: var(--surface);
  color: var(--ink);
}

/* Breadcrumbs */
.breadcrumbs {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.9rem;
  color: var(--muted);
  margin-top: 2rem;
}

.breadcrumbs a {
  color: var(--muted);
  transition: color 0.15s;
}

.breadcrumbs a:hover {
  color: var(--ink);
}

.breadcrumbs span.sep {
  opacity: 0.5;
}

/* Blog Hub Layout */
.blog-hero {
  padding: 3.5rem 0 2rem;
  text-align: center;
}

.blog-hero h1 {
  font-size: clamp(2.3rem, 5vw, 3.8rem);
  font-weight: 800;
  margin-bottom: 1rem;
}

.blog-hero p {
  color: var(--muted);
  font-size: 1.15rem;
  max-width: 36rem;
  margin: 0 auto;
}

.blog-filters {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.6rem;
  margin: 2.2rem 0 3rem;
}

.filter-chip {
  padding: 0.4rem 0.95rem;
  border-radius: 99px;
  border: 1px solid var(--line);
  background: var(--surface);
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--muted);
  cursor: pointer;
  transition: all 0.15s;
}

.filter-chip.active, .filter-chip:hover {
  background: var(--accent);
  color: var(--accent-ink);
  border-color: var(--accent);
}

.posts-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(330px, 1fr));
  gap: 2rem;
  margin-bottom: 5rem;
}

.post-card {
  display: flex;
  flex-direction: column;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 20px;
  overflow: hidden;
  transition: transform 0.25s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.25s, border-color 0.25s;
  text-decoration: none;
  position: relative;
}

.post-card:hover {
  transform: translateY(-5px);
  border-color: color-mix(in srgb, var(--accent) 60%, var(--line));
  box-shadow: 0 20px 40px -15px rgba(16, 19, 34, 0.12), 0 0 0 1px color-mix(in srgb, var(--accent) 30%, transparent);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .post-card:hover {
    box-shadow: 0 24px 50px -20px rgba(0, 0, 0, 0.8), 0 0 0 1px color-mix(in srgb, var(--accent) 40%, transparent);
  }
}

/* Bespoke Visual Stages for Each Card */
.card-art {
  height: 175px;
  position: relative;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  border-bottom: 1px solid var(--line);
  padding: 1.25rem;
  user-select: none;
}

/* Background Gradients */
.art-pdf {
  background: radial-gradient(circle at 50% 30%, rgba(239, 68, 68, 0.2), transparent 70%),
              linear-gradient(135deg, #181926 0%, #0e1019 100%);
}
.art-ocr {
  background: radial-gradient(circle at 50% 30%, rgba(16, 185, 129, 0.2), transparent 70%),
              linear-gradient(135deg, #102120 0%, #0e1019 100%);
}
.art-transfer {
  background: radial-gradient(circle at 50% 30%, rgba(168, 85, 247, 0.22), transparent 70%),
              linear-gradient(135deg, #1d182e 0%, #0e1019 100%);
}
.art-markdown {
  background: radial-gradient(circle at 50% 30%, rgba(59, 130, 246, 0.22), transparent 70%),
              linear-gradient(135deg, #131d33 0%, #0e1019 100%);
}

.card-pill-tag {
  position: absolute;
  top: 1rem;
  left: 1rem;
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 0.25rem 0.6rem;
  border-radius: 99px;
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(8px);
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.15);
}

/* PDF Card Art Components */
.art-pdf-stage {
  display: flex;
  align-items: center;
  gap: 1rem;
}
.mini-chat-bubble {
  background: rgba(255, 255, 255, 0.07);
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: 12px;
  padding: 0.55rem 0.85rem;
  color: #e2e8f0;
  font-size: 0.78rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.arrow-flow {
  display: flex;
  align-items: center;
  color: #ef4444;
  font-size: 1.1rem;
  font-weight: 800;
}
.floating-doc {
  background: #ffffff;
  border-radius: 10px;
  padding: 0.65rem 0.85rem;
  box-shadow: 0 15px 35px -5px rgba(0, 0, 0, 0.5);
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  width: 90px;
  position: relative;
  transform: rotate(3deg);
  transition: transform 0.3s;
}
.post-card:hover .floating-doc {
  transform: rotate(0deg) scale(1.05);
}
.doc-badge-pdf {
  font-size: 0.65rem;
  font-weight: 800;
  background: #ef4444;
  color: #fff;
  padding: 0.1rem 0.35rem;
  border-radius: 4px;
  width: fit-content;
}
.doc-skeleton-line {
  height: 4px;
  background: #cbd5e1;
  border-radius: 2px;
}
.doc-skeleton-line.short { width: 60%; }

/* OCR Card Art Components */
.art-ocr-stage {
  width: 85%;
  max-width: 250px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(16, 185, 129, 0.25);
  border-radius: 12px;
  padding: 0.9rem;
  position: relative;
}
.ocr-beam {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent, #10b981, #34d399, transparent);
  box-shadow: 0 0 12px #10b981;
  animation: scan 2.5s ease-in-out infinite alternate;
}
@keyframes scan {
  from { top: 15%; opacity: 0.4; }
  to { top: 85%; opacity: 1; }
}
.ocr-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.8rem;
  color: #94a3b8;
  margin-bottom: 0.4rem;
}
.ocr-row:last-child { margin-bottom: 0; }
.ocr-tag {
  color: #34d399;
  font-weight: 600;
  font-size: 0.72rem;
  background: rgba(16, 185, 129, 0.15);
  padding: 0.1rem 0.45rem;
  border-radius: 4px;
}

/* Transfer Card Art Components */
.art-transfer-stage {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.8rem;
  width: 100%;
}
.ai-node-pill {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.55rem 0.85rem;
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.15);
  color: #fff;
  font-size: 0.82rem;
  font-weight: 600;
  box-shadow: 0 10px 25px -10px rgba(0,0,0,0.4);
}
.ai-node-pill.chatgpt { border-color: rgba(16, 185, 129, 0.4); }
.ai-node-pill.claude { border-color: rgba(217, 119, 6, 0.4); }
.transfer-bridge {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.2rem;
}
.bridge-line {
  width: 44px;
  height: 2px;
  background: repeating-linear-gradient(90deg, #a855f7 0 6px, transparent 6px 12px);
  animation: bridgeFlow 1.2s linear infinite;
}
@keyframes bridgeFlow {
  to { background-position: 12px 0; }
}
.bridge-badge {
  font-size: 0.65rem;
  color: #c084fc;
  font-weight: 700;
  text-transform: uppercase;
}

/* Markdown Card Art Components */
.art-markdown-stage {
  width: 85%;
  max-width: 250px;
  background: #090d16;
  border: 1px solid rgba(59, 130, 246, 0.3);
  border-radius: 12px;
  padding: 0.8rem 1rem;
  box-shadow: 0 15px 30px -10px rgba(0,0,0,0.6);
  position: relative;
}
.editor-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 0.5rem;
  padding-bottom: 0.35rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}
.editor-dots {
  display: flex;
  gap: 4px;
}
.editor-dots i {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.2);
}
.editor-filename {
  font-family: "JetBrains Mono", monospace;
  font-size: 0.72rem;
  color: #94a3b8;
}
.editor-code {
  font-family: "JetBrains Mono", monospace;
  font-size: 0.74rem;
  color: #60a5fa;
  line-height: 1.4;
}

/* Card Body & Footer */
.post-card-body {
  padding: 1.6rem 1.7rem;
  display: flex;
  flex-direction: column;
  flex-grow: 1;
}

.post-card-meta {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
  font-size: 0.85rem;
  color: var(--muted);
}

.post-tag {
  display: inline-block;
  padding: 0.2rem 0.65rem;
  border-radius: 6px;
  font-weight: 700;
  font-size: 0.76rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}
.post-tag.pdf { background: rgba(239, 68, 68, 0.12); color: #ef4444; }
.post-tag.doc { background: rgba(16, 185, 129, 0.12); color: #10b981; }
.post-tag.transfer { background: rgba(168, 85, 247, 0.12); color: #a855f7; }
.post-tag.pkm { background: rgba(59, 130, 246, 0.12); color: #3b82f6; }

.post-card h2 {
  font-size: 1.25rem;
  font-weight: 700;
  line-height: 1.35;
  margin-bottom: 0.65rem;
  color: var(--ink);
  transition: color 0.15s;
}
.post-card:hover h2 {
  color: var(--accent);
}

.post-card p {
  color: var(--muted);
  font-size: 0.95rem;
  line-height: 1.6;
  margin: 0;
  flex-grow: 1;
}

.post-card-footer {
  margin-top: 1.35rem;
  padding-top: 1rem;
  border-top: 1px solid var(--line);
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.88rem;
  color: var(--accent);
  font-weight: 600;
}

.post-card-footer span {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  transition: transform 0.2s;
}

.post-card:hover .post-card-footer span {
  transform: translateX(4px);
}

/* Article Reading View */
.article-header {
  padding: 2.5rem 0 2rem;
  border-bottom: 1px solid var(--line);
  margin-bottom: 2.5rem;
}

.article-header h1 {
  font-size: clamp(2.2rem, 4.6vw, 3.4rem);
  font-weight: 800;
  margin: 1rem 0;
  line-height: 1.18;
}

.article-lead {
  font-size: 1.22rem;
  line-height: 1.65;
  color: var(--muted);
  margin: 0 0 1.5rem;
}

.article-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1.25rem;
  color: var(--muted);
  font-size: 0.92rem;
}

.author-pill {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 600;
  color: var(--ink);
}

.author-pill img {
  width: 26px;
  height: 26px;
  border-radius: 50%;
}

.article-body {
  font-size: 1.08rem;
  line-height: 1.8;
  color: var(--ink);
}

.article-body h2 {
  font-size: 1.85rem;
  font-weight: 800;
  margin: 3rem 0 1.2rem;
  padding-top: 1rem;
  border-top: 1px solid var(--line);
}

.article-body h2:first-of-type {
  border-top: none;
  margin-top: 1.5rem;
}

.article-body h3 {
  font-size: 1.35rem;
  font-weight: 700;
  margin: 2rem 0 0.8rem;
}

.article-body p {
  margin: 0 0 1.5rem;
}

.article-body strong {
  font-weight: 600;
  color: var(--ink);
}

.article-body ul, .article-body ol {
  margin: 0 0 1.6rem;
  padding-left: 1.4rem;
}

.article-body li {
  margin-bottom: 0.55rem;
}

.article-body a {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.article-body a:hover {
  text-decoration-thickness: 2px;
}

/* Callouts */
.callout {
  background: var(--surface);
  border: 1px solid var(--line);
  border-left: 4px solid var(--accent);
  border-radius: 12px;
  padding: 1.3rem 1.5rem;
  margin: 2rem 0;
}

.callout.tip {
  border-left-color: #10b981;
  background: color-mix(in srgb, #10b981 6%, var(--surface));
}

.callout.warning {
  border-left-color: #f59e0b;
  background: color-mix(in srgb, #f59e0b 6%, var(--surface));
}

.callout h4 {
  font-size: 1.05rem;
  margin-bottom: 0.35rem;
}

.callout p:last-child {
  margin-bottom: 0;
}

/* Code & Pre */
pre {
  background: var(--code-bg);
  color: var(--code-ink);
  padding: 1.25rem;
  border-radius: 12px;
  overflow-x: auto;
  font-family: "JetBrains Mono", monospace;
  font-size: 0.9rem;
  line-height: 1.6;
  margin: 1.6rem 0;
  border: 1px solid var(--line);
}

code {
  font-family: "JetBrains Mono", monospace;
  font-size: 0.9em;
  background: var(--surface-alt);
  padding: 0.15rem 0.4rem;
  border-radius: 6px;
  border: 1px solid var(--line);
}

pre code {
  background: none;
  border: none;
  padding: 0;
}

kbd {
  font-family: "JetBrains Mono", monospace;
  font-size: 0.85em;
  display: inline-block;
  padding: 0.1rem 0.45rem;
  border: 1px solid var(--line);
  border-radius: 5px;
  background: var(--surface);
  box-shadow: 0 1px 1px rgba(0,0,0,0.15);
}

/* Process steps */
.process-list {
  counter-reset: step-counter;
  list-style: none;
  padding: 0;
  margin: 2rem 0;
}

.process-step {
  counter-increment: step-counter;
  position: relative;
  padding-left: 3.2rem;
  margin-bottom: 2rem;
}

.process-step::before {
  content: counter(step-counter);
  position: absolute;
  left: 0;
  top: 0;
  width: 2.2rem;
  height: 2.2rem;
  border-radius: 50%;
  background: var(--accent);
  color: var(--accent-ink);
  display: grid;
  place-items: center;
  font-weight: 700;
  font-family: "Bricolage Grotesque", sans-serif;
  font-size: 1rem;
}

.process-step h3 {
  margin-top: 0;
  margin-bottom: 0.5rem;
}

/* Tables */
.article-table {
  width: 100%;
  border-collapse: collapse;
  margin: 2rem 0;
  border: 1px solid var(--line);
  border-radius: 12px;
  overflow: hidden;
  background: var(--surface);
}

.article-table th, .article-table td {
  padding: 0.85rem 1.1rem;
  text-align: left;
  border-bottom: 1px solid var(--line);
}

.article-table tr:last-child td {
  border-bottom: none;
}

.article-table th {
  background: var(--surface-alt);
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--muted);
}

/* Figures */
figure {
  margin: 2.5rem 0;
}

figure img {
  border-radius: 14px;
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
}

figcaption {
  font-size: 0.88rem;
  color: var(--muted);
  text-align: center;
  margin-top: 0.65rem;
}

/* In-Article CTA Banner */
.article-cta {
  background: linear-gradient(135deg, color-mix(in srgb, var(--accent) 15%, var(--surface)), var(--surface));
  border: 1px solid color-mix(in srgb, var(--accent) 35%, var(--line));
  border-radius: 18px;
  padding: 2.2rem;
  margin: 3.5rem 0;
  text-align: center;
}

.article-cta h3 {
  font-size: 1.6rem;
  font-weight: 800;
  margin-bottom: 0.6rem;
}

.article-cta p {
  color: var(--muted);
  max-width: 32rem;
  margin: 0 auto 1.5rem;
  font-size: 1.05rem;
}

.article-cta .actions {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.8rem;
}

/* FAQ Details */
details {
  border-top: 1px solid var(--line);
  padding: 1.1rem 0;
}

details:last-of-type {
  border-bottom: 1px solid var(--line);
}

summary {
  cursor: pointer;
  font: 600 1.15rem "Bricolage Grotesque", sans-serif;
  list-style: none;
  display: flex;
  justify-content: space-between;
  gap: 1rem;
}

summary::after {
  content: "+";
  color: var(--accent);
  font-size: 1.4rem;
  line-height: 1;
}

details[open] summary::after {
  content: "–";
}

details p {
  color: var(--muted);
  margin: 0.8rem 0 0;
}

/* Footer */
footer {
  border-top: 1px solid var(--line);
  padding: 3rem 0;
  color: var(--muted);
  font-size: 0.95rem;
  margin-top: 4rem;
}

footer .wrap {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 1.5rem;
}

footer ul {
  display: flex;
  gap: 1.5rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

@media (max-width: 860px) {
  .menu {
    display: block;
  }
  nav ul {
    display: none;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: flex-start;
    background: var(--bg);
    border-bottom: 1px solid var(--line);
    padding: 1.25rem;
    gap: 1.1rem;
  }
  nav ul.open {
    display: flex;
  }
}