@import url('https://fonts.googleapis.com/css2?family=IBM+Plex+Mono:wght@400;500&family=IBM+Plex+Sans+Thai:wght@300;400;500;600&display=swap');

/* ── Tokens ── */
:root {
  --color-white: #FFFFFF;
  --color-black: #0A0A0A;
  --color-blue: #007AFF;
  --color-blue-dim: rgba(0, 122, 255, 0.08);
  --color-blue-border: rgba(0, 122, 255, 0.18);
  --color-blue-glow: rgba(0, 122, 255, 0.30);
  --color-gray-50: #F9F9F9;
  --color-gray-100: #F2F2F2;
  --color-gray-200: #E5E5E5;
  --color-gray-300: #D0D0D0;
  --color-gray-400: #AAAAAA;
  --color-gray-500: #888888;
  --color-gray-700: #444444;
  --color-gray-900: #111111;
  --color-red: #FF3B30;
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-6: 48px;
  --space-8: 64px;
  --space-10: 80px;
  --space-15: 120px;
}

/* ── Reset ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

/* ── Base ── */
html { scroll-behavior: smooth; }

body {
  font-family: 'SF Pro Text', -apple-system, BlinkMacSystemFont, 'Helvetica Neue', Arial, sans-serif;
  font-size: 17px;
  font-weight: 400;
  line-height: 1.7;
  letter-spacing: -0.01em;
  color: var(--color-gray-700);
  background: var(--color-white);
  -webkit-font-smoothing: antialiased;
}

img { display: block; max-width: 100%; }
a { color: inherit; }

/* ── Thai mode ── */
body.lang-th {
  font-family: 'IBM Plex Sans Thai', sans-serif;
  font-size: 108%;
  line-height: 1.8;
}
body.lang-th h1,
body.lang-th h2,
body.lang-th h3 { letter-spacing: 0; }

.th { display: none; }
body.lang-th .en { display: none; }
body.lang-th .th {
  display: revert;
}

/* ── Navigation ── */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: 64px;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border-bottom: 1px solid var(--color-gray-200);
  z-index: 100;
  display: flex;
  align-items: center;
}

.nav-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 var(--space-6);
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  text-decoration: none;
  color: var(--color-black);
  font-family: 'SF Pro Display', -apple-system, BlinkMacSystemFont, 'Helvetica Neue', Arial, sans-serif;
  font-size: 17px;
  font-weight: 600;
  letter-spacing: -0.02em;
}

.nav-right {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  list-style: none;
}

.nav-links a {
  font-size: 14px;
  font-weight: 400;
  color: var(--color-gray-500);
  text-decoration: none;
  transition: color 0.2s;
}
.nav-links a:hover { color: var(--color-black); }

/* ── Red Dot ── */
.red-dot {
  width: 8px;
  height: 8px;
  background: var(--color-red);
  border-radius: 50%;
  flex-shrink: 0;
  animation: pulse-dot 2s infinite;
}

@keyframes pulse-dot {
  0%   { box-shadow: 0 0 0 0 rgba(255, 59, 48, 0.6); }
  70%  { box-shadow: 0 0 0 8px rgba(255, 59, 48, 0); }
  100% { box-shadow: 0 0 0 0 rgba(255, 59, 48, 0); }
}

/* ── Language toggle ── */
.lang-toggle {
  display: flex;
  align-items: center;
  gap: 5px;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 13px;
  text-transform: uppercase;
}

.lang-btn {
  background: none;
  border: none;
  cursor: pointer;
  font-family: inherit;
  font-size: inherit;
  text-transform: inherit;
  padding: 0;
  color: var(--color-gray-400);
  transition: color 0.2s;
  line-height: 1;
}
.lang-btn.active { color: var(--color-black); }
.lang-btn:hover { color: var(--color-black); }

.lang-sep {
  color: var(--color-gray-300);
  user-select: none;
}

/* ── Buttons ── */
.btn-nav {
  display: inline-flex;
  align-items: center;
  background: var(--color-black);
  color: var(--color-white);
  border: none;
  border-radius: 8px;
  padding: 8px 18px;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  text-decoration: none;
  transition: background 0.2s;
  white-space: nowrap;
}
.btn-nav:hover { background: var(--color-gray-900); }

.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: var(--color-blue);
  color: var(--color-white);
  border: none;
  border-radius: 8px;
  padding: 13px 24px;
  font-size: 15px;
  font-weight: 500;
  cursor: pointer;
  text-decoration: none;
  transition: background 0.2s, transform 0.15s;
}
.btn-primary:hover { background: #0066DD; transform: translateY(-1px); }

.btn-ghost {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: transparent;
  color: var(--color-gray-700);
  border: 1px solid var(--color-gray-300);
  border-radius: 8px;
  padding: 13px 24px;
  font-size: 15px;
  font-weight: 400;
  cursor: pointer;
  text-decoration: none;
  transition: border-color 0.2s, color 0.2s;
}
.btn-ghost:hover { border-color: var(--color-gray-500); color: var(--color-black); }

/* ── Layout ── */
main { padding-top: 64px; }

.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 var(--space-6);
}

/* ── Typography ── */
h1 {
  font-family: 'SF Pro Display', -apple-system, BlinkMacSystemFont, 'Helvetica Neue', Arial, sans-serif;
  font-size: clamp(36px, 4vw, 54px);
  font-weight: 600;
  line-height: 1.08;
  letter-spacing: -0.04em;
  color: var(--color-black);
}

h2 {
  font-family: 'SF Pro Display', -apple-system, BlinkMacSystemFont, 'Helvetica Neue', Arial, sans-serif;
  font-size: clamp(28px, 3vw, 44px);
  font-weight: 600;
  line-height: 1.1;
  letter-spacing: -0.03em;
  color: var(--color-black);
}

h3 {
  font-family: 'SF Pro Text', -apple-system, BlinkMacSystemFont, 'Helvetica Neue', Arial, sans-serif;
  font-size: 20px;
  font-weight: 600;
  line-height: 1.2;
  letter-spacing: -0.03em;
  color: var(--color-black);
}

body.lang-th h1,
body.lang-th h2,
body.lang-th h3 {
  font-family: 'IBM Plex Sans Thai', sans-serif;
}

/* ── Eyebrow ── */
.eyebrow {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 11px;
  font-weight: 500;
  color: var(--color-blue);
  letter-spacing: 0.10em;
  text-transform: uppercase;
  margin-bottom: var(--space-2);
  display: block;
}

/* ── Badge ── */
.badge {
  display: inline-flex;
  align-items: center;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 11px;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  background: var(--color-blue-dim);
  border: 1px solid var(--color-blue-border);
  color: var(--color-blue);
  padding: 4px 10px;
  border-radius: 6px;
  white-space: nowrap;
}

.badge-gray {
  background: var(--color-gray-100);
  border-color: var(--color-gray-200);
  color: var(--color-gray-500);
}

/* ── Card ── */
.card {
  background: var(--color-gray-100);
  border: 1px solid var(--color-gray-200);
  border-radius: 16px;
  overflow: hidden;
}

/* ── Divider ── */
.divider {
  border: none;
  border-top: 1px solid var(--color-gray-200);
}

/* ── Footer ── */
footer {
  padding: 40px 0;
  border-top: 1px solid var(--color-gray-200);
}

.footer-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 var(--space-6);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  text-decoration: none;
  color: var(--color-black);
  font-family: 'SF Pro Display', -apple-system, BlinkMacSystemFont, 'Helvetica Neue', Arial, sans-serif;
  font-size: 15px;
  font-weight: 600;
  letter-spacing: -0.02em;
}

.footer-meta {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 12px;
  color: var(--color-gray-400);
  text-align: right;
  line-height: 1.6;
}

.footer-links {
  display: flex;
  gap: var(--space-4);
  list-style: none;
}

.footer-links a {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 12px;
  color: var(--color-gray-400);
  text-decoration: none;
  transition: color 0.2s;
}
.footer-links a:hover { color: var(--color-black); }

/* ── Scroll reveal ── */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.65s cubic-bezier(0.22, 1, 0.36, 1),
              transform 0.65s cubic-bezier(0.22, 1, 0.36, 1);
}
.reveal.visible { opacity: 1; transform: translateY(0); }

.stagger > *:nth-child(1) { transition-delay: 0s; }
.stagger > *:nth-child(2) { transition-delay: 0.1s; }
.stagger > *:nth-child(3) { transition-delay: 0.2s; }
.stagger > *:nth-child(4) { transition-delay: 0.3s; }

/* ── Focus ── */
:focus-visible {
  outline: none;
  box-shadow: 0 0 0 3px rgba(0, 122, 255, 0.5);
  border-radius: 4px;
}

/* ═══════════════════════════════════════
   BLOG HOMEPAGE
═══════════════════════════════════════ */

/* Blog Hero */
.blog-hero {
  padding: var(--space-15) 0 var(--space-10);
  position: relative;
  overflow: hidden;
}

.blog-hero::before {
  content: '';
  position: absolute;
  top: -200px; right: -200px;
  width: 700px; height: 700px;
  background: radial-gradient(circle, rgba(0, 122, 255, 0.05) 0%, transparent 70%);
  pointer-events: none;
}

.blog-hero-content {
  position: relative;
  max-width: 720px;
}

.blog-hero-label {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  margin-bottom: var(--space-4);
}

.blog-hero h1 {
  margin-bottom: var(--space-3);
}

.blog-hero-sub {
  font-size: 17px;
  color: var(--color-gray-500);
  max-width: 560px;
}

/* Article grid */
.articles-section {
  padding: var(--space-10) 0 var(--space-15);
  border-top: 1px solid var(--color-gray-200);
}

.articles-section-header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: var(--space-6);
}

/* Featured article card */
.article-card-featured {
  display: grid;
  grid-template-columns: 1fr 1fr;
  background: var(--color-gray-100);
  border: 1px solid var(--color-gray-200);
  border-radius: 16px;
  overflow: hidden;
  text-decoration: none;
  color: inherit;
  transition: border-color 0.2s;
}
.article-card-featured:hover { border-color: var(--color-gray-300); }

.article-card-featured:hover .article-card-img {
  transform: scale(1.02);
}

.article-card-img-wrap {
  overflow: hidden;
  aspect-ratio: 4/3;
}

.article-card-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s cubic-bezier(0.22, 1, 0.36, 1);
}

.article-card-body {
  padding: var(--space-6);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: var(--space-4);
}

.article-card-meta {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  flex-wrap: wrap;
}

.article-card-date {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 12px;
  color: var(--color-gray-400);
  letter-spacing: 0.02em;
}

.article-card-title {
  font-family: 'SF Pro Display', -apple-system, BlinkMacSystemFont, 'Helvetica Neue', Arial, sans-serif;
  font-size: clamp(22px, 2vw, 30px);
  font-weight: 600;
  line-height: 1.15;
  letter-spacing: -0.03em;
  color: var(--color-black);
}

body.lang-th .article-card-title {
  font-family: 'IBM Plex Sans Thai', sans-serif;
  font-size: clamp(20px, 2vw, 28px);
  letter-spacing: 0;
  line-height: 1.3;
}

.article-card-excerpt {
  font-size: 15px;
  color: var(--color-gray-500);
  line-height: 1.7;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.article-card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: var(--space-3);
  border-top: 1px solid var(--color-gray-200);
}

.article-card-author {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 11px;
  color: var(--color-gray-400);
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.read-more {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 12px;
  font-weight: 500;
  color: var(--color-blue);
  letter-spacing: 0.04em;
  text-transform: uppercase;
  display: flex;
  align-items: center;
  gap: 4px;
  text-decoration: none;
  transition: gap 0.2s;
}
.read-more:hover { gap: 8px; }

/* ═══════════════════════════════════════
   ARTICLE PAGE
═══════════════════════════════════════ */

/* Article header */
.article-header {
  padding: var(--space-15) 0 var(--space-8);
  position: relative;
  overflow: hidden;
}

.article-header::before {
  content: '';
  position: absolute;
  top: -150px; right: -150px;
  width: 600px; height: 600px;
  background: radial-gradient(circle, rgba(0, 122, 255, 0.04) 0%, transparent 70%);
  pointer-events: none;
}

.article-header-inner {
  position: relative;
  max-width: 760px;
}

.article-header-meta {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  flex-wrap: wrap;
  margin-bottom: var(--space-4);
}

.article-date {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 12px;
  color: var(--color-gray-400);
  letter-spacing: 0.02em;
}

.article-header h1 {
  font-size: clamp(30px, 3.5vw, 48px);
  margin-bottom: var(--space-4);
}

body.lang-th .article-header h1 {
  font-family: 'IBM Plex Sans Thai', sans-serif;
  letter-spacing: 0;
  line-height: 1.2;
}

.article-byline {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-family: 'IBM Plex Mono', monospace;
  font-size: 12px;
  color: var(--color-gray-400);
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.article-byline-dot {
  width: 3px; height: 3px;
  background: var(--color-gray-300);
  border-radius: 50%;
}

/* Featured image */
.article-featured-image {
  width: 100%;
  border-top: 1px solid var(--color-gray-200);
  border-bottom: 1px solid var(--color-gray-200);
  overflow: hidden;
  max-height: 520px;
}

.article-featured-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

/* Article body */
.article-layout {
  display: grid;
  grid-template-columns: 1fr min(720px, 100%) 1fr;
  padding: var(--space-10) var(--space-6);
}

.article-body {
  grid-column: 2;
}

/* Article typography */
.article-body p {
  font-size: 17px;
  line-height: 1.75;
  color: var(--color-gray-700);
  margin-bottom: var(--space-4);
}

body.lang-th .article-body p {
  font-size: 108%;
  line-height: 1.9;
}

.article-body h2 {
  font-size: clamp(22px, 2.5vw, 30px);
  margin-top: var(--space-10);
  margin-bottom: var(--space-4);
}

body.lang-th .article-body h2 {
  font-family: 'IBM Plex Sans Thai', sans-serif;
  letter-spacing: 0;
}

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

.article-body a {
  color: var(--color-blue);
  text-decoration: none;
  border-bottom: 1px solid var(--color-blue-border);
  transition: border-color 0.2s;
}
.article-body a:hover { border-color: var(--color-blue); }

.article-body hr {
  border: none;
  border-top: 1px solid var(--color-gray-200);
  margin: var(--space-8) 0;
}

.article-body ul {
  padding-left: var(--space-4);
  margin-bottom: var(--space-4);
}

.article-body li {
  font-size: 17px;
  line-height: 1.75;
  color: var(--color-gray-700);
  margin-bottom: var(--space-2);
}

/* Comparison table */
.article-table-wrap {
  overflow-x: auto;
  margin: var(--space-6) 0;
  border-radius: 12px;
  border: 1px solid var(--color-gray-200);
}

.article-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 15px;
  min-width: 500px;
}

.article-table th {
  background: var(--color-gray-100);
  font-family: 'IBM Plex Mono', monospace;
  font-size: 11px;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--color-gray-500);
  padding: 14px var(--space-4);
  text-align: left;
  border-bottom: 1px solid var(--color-gray-200);
}

.article-table th:first-child { border-radius: 12px 0 0 0; }
.article-table th:last-child { border-radius: 0 12px 0 0; }

.article-table td {
  padding: 14px var(--space-4);
  border-bottom: 1px solid var(--color-gray-200);
  color: var(--color-gray-700);
  line-height: 1.5;
  vertical-align: top;
}

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

.article-table td:first-child {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 12px;
  font-weight: 500;
  color: var(--color-gray-500);
  white-space: nowrap;
}

.article-table td strong {
  color: var(--color-black);
}

.article-table tr:nth-child(even) td {
  background: var(--color-gray-50);
}

/* Disclaimer */
.article-disclaimer {
  font-size: 14px;
  color: var(--color-gray-400);
  font-style: italic;
  line-height: 1.7;
  padding: var(--space-4);
  border-left: 3px solid var(--color-gray-200);
  margin: var(--space-8) 0;
}

body.lang-th .article-disclaimer {
  font-family: 'IBM Plex Sans Thai', sans-serif;
}

/* References */
.article-references {
  margin-top: var(--space-8);
  padding-top: var(--space-6);
  border-top: 1px solid var(--color-gray-200);
}

.article-references h3 {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 11px;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.10em;
  color: var(--color-gray-400);
  margin-bottom: var(--space-4);
}

.article-references ol {
  padding-left: var(--space-3);
  counter-reset: ref-counter;
  list-style: none;
}

.article-references li {
  font-size: 12px;
  color: var(--color-gray-500);
  line-height: 1.6;
  margin-bottom: 10px;
  padding-left: var(--space-4);
  position: relative;
  font-family: 'IBM Plex Mono', monospace;
}

.article-references li::before {
  content: counter(ref-counter, decimal-leading-zero);
  counter-increment: ref-counter;
  position: absolute;
  left: 0;
  color: var(--color-gray-300);
  font-size: 11px;
  top: 2px;
}

.article-references a {
  color: var(--color-gray-500);
  text-decoration: none;
  border-bottom: 1px solid var(--color-gray-200);
  transition: color 0.2s, border-color 0.2s;
  word-break: break-all;
}
.article-references a:hover { color: var(--color-blue); border-color: var(--color-blue); }

/* Article CTA */
.article-cta-section {
  background: var(--color-gray-50);
  border-top: 1px solid var(--color-gray-200);
  padding: var(--space-10) 0;
}

.article-cta-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 var(--space-6);
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-8);
  align-items: center;
}

.article-cta-text h2 {
  font-size: clamp(24px, 2.5vw, 36px);
  margin-bottom: var(--space-3);
}

body.lang-th .article-cta-text h2 {
  font-family: 'IBM Plex Sans Thai', sans-serif;
  letter-spacing: 0;
}

.article-cta-text p {
  font-size: 15px;
  color: var(--color-gray-500);
  line-height: 1.7;
  margin-bottom: var(--space-4);
}

body.lang-th .article-cta-text p {
  font-family: 'IBM Plex Sans Thai', sans-serif;
}

.article-cta-buttons {
  display: flex;
  gap: var(--space-2);
  flex-wrap: wrap;
}

.article-cta-contact {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.contact-row {
  display: flex;
  gap: var(--space-4);
  font-family: 'IBM Plex Mono', monospace;
  font-size: 13px;
  padding: var(--space-2) 0;
  border-bottom: 1px solid var(--color-gray-200);
}

.contact-label { color: var(--color-gray-400); min-width: 80px; }
.contact-value { color: var(--color-gray-700); }

/* Back link */
.back-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 12px;
  font-weight: 500;
  color: var(--color-gray-500);
  text-decoration: none;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  padding: var(--space-6) var(--space-6) 0;
  max-width: 1280px;
  margin: 0 auto;
  display: block;
  transition: color 0.2s;
}
.back-link:hover { color: var(--color-black); }
.back-link span { display: inline-flex; align-items: center; gap: 6px; }

/* ── Responsive ── */
@media (max-width: 1024px) {
  .nav-inner,
  .container,
  .footer-inner,
  .article-cta-inner { padding-left: var(--space-3); padding-right: var(--space-3); }
  .article-layout { padding-left: var(--space-3); padding-right: var(--space-3); }
  .back-link { padding-left: var(--space-3); }
  .article-cta-inner { grid-template-columns: 1fr; gap: var(--space-6); }
}

@media (max-width: 768px) {
  .article-card-featured { grid-template-columns: 1fr; }
  .article-card-img-wrap { aspect-ratio: 16/9; }
}

@media (max-width: 640px) {
  .nav-inner,
  .container,
  .footer-inner,
  .article-layout,
  .article-cta-inner { padding-left: var(--space-2); padding-right: var(--space-2); }

  .back-link { padding-left: var(--space-2); }

  .nav-links { display: none; }
  .lang-toggle { display: none; }

  .blog-hero { padding: 60px 0 var(--space-8); }
  .articles-section { padding: var(--space-8) 0 var(--space-10); }
  .article-header { padding: 60px 0 var(--space-6); }
  .article-layout { padding-top: var(--space-8); padding-bottom: var(--space-8); }
  .article-cta-section { padding: var(--space-8) 0; }

  .article-cta-inner { gap: var(--space-4); }
  .footer-inner { flex-direction: column; align-items: flex-start; gap: var(--space-3); }
  .footer-meta { text-align: left; }
  .footer-links { display: none; }
}