/* ═══════════════ ARTICLE PAGE STYLES ═══════════════ */
/* Shared across all /guides/*.html public article pages */

/* --- RESET & ROOT --- */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  background: #F8FAFC;
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  -webkit-font-smoothing: antialiased;
  color: #1a1a2e;
}

:root {
  --blue: #0066FF;
  --blue-light: #EBF3FF;
  --blue-glow: rgba(0,102,255,0.35);
  --green: #10B981;
  --dark: #0F172A;
  --text: #374151;
  --text-light: #6B7280;
  --text-lighter: #9CA3AF;
  --border: rgba(0,0,0,0.06);
  --border-light: rgba(0,0,0,0.03);
  --card-bg: rgba(255,255,255,0.65);
  --muted: #64748B;
  --muted-light: #94A3B8;
}

/* --- AURORA GRADIENT --- */
.aurora-bg {
  position: fixed; top: -120px; left: 0; width: 100%; height: 850px;
  z-index: 0; pointer-events: none;
  background:
    radial-gradient(ellipse 70% 45% at 20% 0%, rgba(0,102,255,0.22) 0%, transparent 60%),
    radial-gradient(ellipse 50% 40% at 80% 0%, rgba(0,163,255,0.18) 0%, transparent 55%),
    radial-gradient(ellipse 60% 30% at 50% 5%, rgba(99,102,241,0.12) 0%, transparent 50%),
    radial-gradient(ellipse 40% 25% at 65% 0%, rgba(139,92,246,0.08) 0%, transparent 45%);
  mask-image: linear-gradient(to bottom, black 0%, black 50%, transparent 100%);
  -webkit-mask-image: linear-gradient(to bottom, black 0%, black 50%, transparent 100%);
}

/* --- TOPBAR --- */
.topbar {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255,255,255,0.6);
  backdrop-filter: blur(24px); -webkit-backdrop-filter: blur(24px);
  border-bottom: 1px solid rgba(0,0,0,0.04);
  box-shadow: 0 4px 30px rgba(0,0,0,0.03);
  padding: 0 24px;
}
.topbar-inner {
  max-width: 1100px; margin: 0 auto;
  height: 60px; display: flex; align-items: center; justify-content: space-between;
}
.topbar-logo { height: 48px; }
.topbar-logo:hover { opacity: 0.85; }

/* --- BUTTONS --- */
.btn-primary {
  height: 44px; padding: 0 24px; border-radius: 100px; font-weight: 700; font-size: 14px;
  cursor: pointer; border: none; display: inline-flex; align-items: center; justify-content: center;
  text-decoration: none; font-family: 'Inter', sans-serif; position: relative; overflow: hidden;
  background: linear-gradient(135deg, #0066FF 0%, #0055DD 100%);
  color: #fff;
  box-shadow: 0 4px 20px var(--blue-glow), 0 1px 3px rgba(0,102,255,0.2);
  transition: all 0.35s cubic-bezier(0.16, 1, 0.3, 1);
}
.btn-primary:hover {
  transform: translateY(-2px) scale(1.02);
  box-shadow: 0 8px 32px var(--blue-glow), 0 2px 6px rgba(0,102,255,0.25);
}
.btn-primary::after {
  content: ""; position: absolute; top: -50%; left: -75%; width: 30%; height: 200%;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
  transform: rotate(30deg); transition: 0.7s;
}
.btn-primary:hover::after { left: 130%; }

.btn-white {
  height: 52px; padding: 0 32px; border-radius: 100px; font-weight: 800; font-size: 15px;
  cursor: pointer; border: none; display: inline-flex; align-items: center; justify-content: center;
  text-decoration: none; font-family: 'Inter', sans-serif;
  background: #fff; color: var(--dark);
  box-shadow: 0 4px 20px rgba(0,0,0,0.08);
  transition: all 0.35s cubic-bezier(0.16, 1, 0.3, 1);
}
.btn-white:hover {
  transform: translateY(-3px) scale(1.02);
  box-shadow: 0 12px 40px rgba(0,0,0,0.12);
}

/* --- ARTICLE LAYOUT --- */
.article-container {
  max-width: 760px; margin: 0 auto;
  padding: 48px 24px 0;
  position: relative; z-index: 1;
}

/* Breadcrumb */
.breadcrumb {
  display: flex; align-items: center; gap: 8px;
  font-size: 13px; color: var(--text-lighter); font-weight: 600;
  margin-bottom: 24px;
}
.breadcrumb a {
  color: var(--text-lighter); text-decoration: none; transition: color 0.2s;
}
.breadcrumb a:hover { color: var(--blue); }
.breadcrumb .sep { opacity: 0.4; }

/* Header */
.article-hero { margin-bottom: 40px; }
.article-hero h1 {
  font-size: clamp(30px, 5vw, 42px); font-weight: 900; letter-spacing: -0.035em;
  color: var(--dark); line-height: 1.12; margin-bottom: 12px;
}
.article-hero .subtitle {
  font-size: 17px; color: var(--text-light); line-height: 1.65; max-width: 600px;
}
.article-meta {
  display: flex; align-items: center; gap: 16px;
  margin-top: 16px; font-size: 13px; color: var(--text-lighter); font-weight: 500;
}
.article-meta .dot { width: 3px; height: 3px; background: var(--text-lighter); border-radius: 50%; }

/* --- ARTICLE BODY --- */
.article-body h2 {
  font-size: 22px; font-weight: 800; color: var(--dark);
  letter-spacing: -0.02em; margin: 48px 0 20px;
  padding-top: 32px; border-top: 1px solid var(--border-light);
}
.article-body h2:first-child { border-top: none; padding-top: 0; margin-top: 0; }
.article-body h3 {
  font-size: 17px; font-weight: 700; color: var(--dark);
  margin: 32px 0 14px;
}
.article-body p {
  font-size: 15.5px; color: var(--text); line-height: 1.78;
  margin-bottom: 20px;
}
.article-body strong { color: var(--dark); font-weight: 700; }
.article-body a { color: var(--blue); text-decoration: none; font-weight: 600; }
.article-body a:hover { text-decoration: underline; }

.article-body ul, .article-body ol {
  margin: 0 0 20px 0; padding-left: 24px;
}
.article-body li {
  font-size: 15px; color: var(--text); line-height: 1.78;
  margin-bottom: 8px;
}

/* Tables */
.article-body table {
  width: 100%; border-collapse: collapse; margin: 28px 0;
  font-size: 14px;
}
.article-body th {
  text-align: left; padding: 12px 16px;
  font-weight: 700; color: var(--dark);
  background: rgba(248,250,252,0.8); border-bottom: 2px solid rgba(0,0,0,0.06);
  font-size: 13px;
}
.article-body td {
  padding: 12px 16px; border-bottom: 1px solid rgba(0,0,0,0.04);
  color: var(--text); line-height: 1.5;
}
.article-body tr:hover td { background: rgba(0,102,255,0.03); }

/* Callout boxes */
.callout {
  padding: 18px 22px; border-radius: 14px;
  margin: 28px 0; font-size: 14px; line-height: 1.65;
}
.callout-tip {
  background: rgba(240,253,244,0.85); border-left: 3px solid var(--green);
}
.callout-warn {
  background: rgba(255,251,235,0.85); border-left: 3px solid #F59E0B;
}
.callout-info {
  background: rgba(235,243,255,0.85); border-left: 3px solid var(--blue);
}
.callout strong { color: var(--dark); }

/* Recommend box */
.recommend-box {
  background: rgba(255,255,255,0.65);
  border: 1px solid rgba(0,102,255,0.08);
  border-radius: 16px; padding: 20px 24px; margin: 32px 0;
  backdrop-filter: blur(12px);
  box-shadow: 0 2px 12px rgba(0,102,255,0.04);
}
.recommend-box .label {
  font-size: 11px; font-weight: 800; text-transform: uppercase;
  letter-spacing: 0.06em; color: var(--blue); margin-bottom: 8px;
}
.recommend-box ul { margin: 0; padding-left: 20px; }
.recommend-box li { font-size: 14px; color: var(--text); line-height: 1.65; margin-bottom: 4px; }

/* Cell colors */
.cell-green { color: #059669; font-weight: 700; }

/* --- MID-ARTICLE CTA --- */
.mid-cta {
  background: linear-gradient(135deg, var(--dark) 0%, #1E293B 50%, #0F172A 100%);
  border-radius: 24px;
  padding: 40px 32px; text-align: center; color: #fff;
  margin: 48px 0;
  position: relative; overflow: hidden;
}
.mid-cta::before {
  content: '';
  position: absolute; top: -60%; right: -25%; width: 70%; height: 160%;
  background: radial-gradient(ellipse, rgba(0,102,255,0.20) 0%, transparent 65%);
  pointer-events: none;
}
.mid-cta h3 {
  font-size: 22px; font-weight: 900; margin: 0 0 8px; letter-spacing: -0.02em; position: relative;
}
.mid-cta p {
  color: var(--muted-light); font-size: 15px; margin: 0 0 20px; position: relative; line-height: 1.6;
}
.mid-cta .btn-white { position: relative; }

/* --- BOTTOM CTA (Signup) --- */
.bottom-cta {
  background: linear-gradient(135deg, #F8FAFC 0%, #EFF3F8 100%);
  border: 1px solid rgba(0,0,0,0.04);
  border-radius: 24px;
  padding: 48px 32px; text-align: center;
  margin: 56px 0 0;
}
.bottom-cta h2 {
  font-size: clamp(22px, 4vw, 30px); font-weight: 900; color: var(--dark);
  letter-spacing: -0.03em; margin: 0 0 8px;
}
.bottom-cta .sub {
  color: var(--text-light); font-size: 15px; line-height: 1.6; margin: 0 0 24px;
}
.signup-form {
  display: flex; gap: 10px; max-width: 440px; margin: 0 auto;
  background: #fff; border-radius: 100px;
  padding: 6px; border: 1px solid rgba(0,0,0,0.06);
  box-shadow: 0 8px 40px rgba(0,0,0,0.06);
}
.signup-form input {
  flex: 1; height: 48px; border-radius: 100px; border: none;
  padding: 0 20px; font-size: 15px; font-family: 'Inter', sans-serif;
  outline: none; background: transparent; min-width: 0;
}
.signup-form input::placeholder { color: var(--muted-light); }
.signup-form .btn-primary { flex-shrink: 0; height: 48px; padding: 0 24px; font-size: 14px; white-space: nowrap; }
.signup-error { color: #EF4444; font-size: 13px; font-weight: 600; margin-top: 8px; min-height: 20px; }
.signup-success {
  display: none; padding: 20px 0; text-align: center;
}
.signup-success h4 { font-weight: 900; font-size: 20px; color: var(--dark); margin: 12px 0 4px; }
.signup-success p { color: var(--text-light); font-size: 14px; }
.success-icon {
  width: 56px; height: 56px; border-radius: 50%;
  background: linear-gradient(135deg, #10B981, #34D399);
  display: inline-flex; align-items: center; justify-content: center;
  box-shadow: 0 8px 30px rgba(16,185,129,0.25);
}

/* --- RELATED GUIDES --- */
.related-guides {
  margin: 56px 0 0;
  padding-top: 40px;
  border-top: 1px solid var(--border);
}
.related-guides h3 {
  font-size: 18px; font-weight: 800; color: var(--dark);
  letter-spacing: -0.02em; margin-bottom: 16px;
}
.related-grid {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
}
.related-card {
  display: block; padding: 20px; border-radius: 16px;
  border: 1px solid rgba(0,0,0,0.05); background: var(--card-bg);
  backdrop-filter: blur(12px);
  text-decoration: none; transition: all 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}
.related-card:hover {
  border-color: rgba(0,102,255,0.12); background: rgba(255,255,255,0.8);
  transform: translateY(-4px);
  box-shadow: 0 16px 40px rgba(0,102,255,0.08), 0 4px 12px rgba(0,0,0,0.03);
}
.related-card .tag {
  font-size: 11px; font-weight: 800; text-transform: uppercase;
  letter-spacing: 0.06em; color: var(--blue); margin-bottom: 6px; display: block;
}
.related-card h4 {
  font-size: 15px; font-weight: 700; color: var(--dark); margin-bottom: 4px;
}
.related-card p {
  font-size: 13px; color: var(--text-light); line-height: 1.5; margin: 0;
}

/* --- FOOTER --- */
.legal-footer { padding: 36px 24px; text-align: center; border-top: 1px solid #F1F5F9; }
.footer-links { margin-bottom: 12px; }
.footer-links a {
  color: var(--muted); text-decoration: none; font-size: 13px; margin: 0 14px;
  font-weight: 600; display: inline-block; transition: color 0.2s;
}
.footer-links a:hover { color: var(--blue); }
.copyright { color: #CBD5E1; font-size: 12px; margin: 0; }

/* --- MOBILE --- */
@media (max-width: 768px) {
  .topbar { padding: 0 16px; }
  .topbar-inner { height: 54px; }
  .topbar-logo { height: 42px; }
  .btn-primary { height: 40px; padding: 0 18px; font-size: 13px; }
  .article-container { padding: 32px 20px 0; }
  .article-hero h1 { font-size: clamp(26px, 7vw, 36px); }
  .article-body table { font-size: 13px; display: block; overflow-x: auto; }
  .mid-cta { padding: 32px 24px; border-radius: 20px; }
  .bottom-cta { padding: 36px 24px; border-radius: 20px; }
  .signup-form { flex-direction: column; border-radius: 20px; padding: 10px; }
  .signup-form input { height: 48px; border-radius: 100px; }
  .signup-form .btn-primary { width: 100%; border-radius: 100px; }
  .related-grid { grid-template-columns: 1fr; }
  .footer-links a { font-size: 11px; margin: 0 8px; }
}
@media (max-width: 480px) {
  .article-meta { flex-wrap: wrap; gap: 8px; }
  .breadcrumb { font-size: 12px; }
}