:root {
  --bg: #020617;
  --bg-elevated: #02081f;
  --card: #020b2b;
  --accent: #22c55e;
  --accent-soft: #16a34a;
  --accent-blue: #38bdf8;
  --text: #e5e7eb;
  --muted: #9ca3af;
  --border: #1f2937;
  --danger: #f97316;
  --radius-lg: 18px;
  --radius-full: 999px;
  --shadow-soft: 0 18px 45px rgba(15,23,42,0.65);
  --max-width: 980px;
}

html, body {
  width: 100%;
  max-width: 100%;
  overflow-x: hidden;
  box-sizing: border-box;
}

*,
*::before,
*::after {
  box-sizing: inherit;
}

body.page {
  margin: 0;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "SF Pro Text", sans-serif;
  background: radial-gradient(circle at top, #0f172a 0, #020617 46%, #000 100%);
  color: var(--text);
}

main {
  max-width: var(--max-width);
  margin: 0 auto 72px;
  padding: 88px 16px 40px;
}

/* Header */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(18px);
  background: linear-gradient(90deg, rgba(15,23,42,0.95), rgba(8,16,40,0.96));
  border-bottom: 1px solid rgba(30,64,175,0.5);
  box-shadow: 0 18px 30px rgba(15,23,42,0.7);
  padding: 10px 16px;
}

.header-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: var(--max-width);
  margin: 0 auto;
  gap: 16px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}

.brand-logo {
  width: 32px;
  height: 32px;
  border-radius: var(--radius-full);
  background: radial-gradient(circle at 30% 20%, #38bdf8, #1d4ed8);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 14px;
  color: #e5f4ff;
  flex-shrink: 0;
}

.brand-text {
  display: flex;
  flex-direction: column;
}

.brand-title {
  font-weight: 600;
  font-size: 15px;
  line-height: 1.3;
}

.brand-subtitle {
  font-size: 11px;
  color: var(--muted);
  line-height: 1.3;
}

.nav {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.nav-link {
  padding: 6px 10px;
  border-radius: 999px;
  color: var(--muted);
  text-decoration: none;
  border: 1px solid transparent;
  white-space: nowrap;
  transition: all 0.2s ease;
}

.nav-link:hover {
  border-color: rgba(148,163,184,0.4);
  color: #f9fafb;
}

.nav-link-primary {
  background: radial-gradient(circle at 10% 0, #22c55e, #16a34a 40%, #0ea5e9 100%);
  color: #f9fafb;
  font-weight: 600;
  box-shadow: 0 0 0 1px rgba(34,197,94,0.45), 0 10px 25px rgba(8,47,73,0.85);
}

.nav-link-primary:hover {
  box-shadow: 0 0 0 1px rgba(34,197,94,0.65), 0 12px 30px rgba(8,47,73,0.95);
  transform: translateY(-1px);
}

.nav-link-primary.active {
  box-shadow: 0 0 0 1px rgba(56,189,248,0.75), 0 0 0 6px rgba(56,189,248,0.25);
}

/* Layout helpers */

.hero {
  background: radial-gradient(circle at top left, #1e293b, #020617 60%);
  border-radius: 24px;
  padding: 26px 18px 26px;
  box-shadow: var(--shadow-soft);
  border: 1px solid rgba(148,163,184,0.25);
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  padding: 4px 10px;
  border-radius: 999px;
  border: 1px solid rgba(148,163,184,0.35);
  font-size: 11px;
  color: var(--muted);
  margin-bottom: 10px;
}

.hero h1 {
  margin: 0 0 10px;
  font-size: 26px;
}

.accent {
  color: var(--accent);
}

.hero-text {
  margin: 0 0 16px;
  color: var(--muted);
  line-height: 1.6;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 10px;
}

.hero-meta {
  margin: 0;
  font-size: 12px;
  color: var(--muted);
}

.card-section {
  margin-top: 28px;
  padding: 24px 20px 28px;
  background: linear-gradient(145deg, rgba(15,23,42,0.96), rgba(2,6,23,0.98));
  border-radius: 24px;
  box-shadow: var(--shadow-soft);
  border: 1px solid rgba(30,64,175,0.6);
  max-width: 960px;
  width: 100%;
  margin-left: auto;
  margin-right: auto;
}

.card-section h2 {
  margin-top: 0;
  margin-bottom: 8px;
  font-size: 20px;
}

.card-section p {
  color: var(--muted);
  line-height: 1.7;
  margin: 8px 0;
}

/* Form / wizard */

.wizard {
  margin-top: 14px;
  display: grid;
  gap: 12px;
}

.field {
  display: grid;
  gap: 6px;
}

.field label {
  font-size: 13px;
}

.field select {
  padding: 10px 12px;
  border-radius: 14px;
  border: 1px solid rgba(55,65,81,0.8);
  background: rgba(15,23,42,0.9);
  color: var(--text);
  font-size: 14px;
  width: 100%;
  max-width: 100%;
}

.result-card {
  margin-top: 16px;
  padding: 14px 14px 16px;
  border-radius: 18px;
  background: radial-gradient(circle at top, #0f172a, #020617);
  border: 1px solid rgba(52,211,153,0.45);
  color: var(--text);
  font-size: 14px;
}

/* Steps */

.steps {
  margin: 10px 0 0;
  padding-left: 18px;
  color: var(--muted);
}

.steps li {
  margin: 6px 0;
}

/* Guide article */

.guide-article h2 {
  margin-top: 32px;
  padding-top: 20px;
  border-top: 1px solid rgba(30,64,175,0.35);
  scroll-margin-top: 80px;
}

.guide-article h2:first-of-type {
  border-top: none;
  padding-top: 0;
}

.guide-article h3 {
  margin-top: 20px;
  font-size: 17px;
  color: var(--accent-blue);
}

.guide-updated {
  font-size: 13px;
  color: var(--accent-blue);
  border-left: 3px solid var(--accent-blue);
  padding-left: 10px;
  margin-bottom: 16px;
}

.guide-updated a {
  color: var(--accent-blue);
}

/* Guide callout boxes */
.guide-callout {
  margin: 20px 0;
  padding: 18px 20px;
  border-radius: 14px;
  border-left: 4px solid var(--accent);
  background: rgba(34,197,94,0.06);
  border: 1px solid rgba(34,197,94,0.25);
  border-left: 4px solid var(--accent);
}

.guide-callout-blue {
  background: rgba(56,189,248,0.06);
  border: 1px solid rgba(56,189,248,0.25);
  border-left: 4px solid var(--accent-blue);
}

.guide-callout-orange {
  background: rgba(249,115,22,0.06);
  border: 1px solid rgba(249,115,22,0.25);
  border-left: 4px solid var(--danger);
}

.guide-callout h3 {
  margin: 0 0 8px;
  font-size: 16px;
  color: var(--text);
}

.guide-callout p, .guide-callout ul {
  margin: 6px 0;
  font-size: 14px;
  color: var(--muted);
  line-height: 1.6;
}

.guide-callout ul {
  padding-left: 18px;
}

.guide-callout li {
  margin: 4px 0;
}

/* Scenario info card */
.scenario-card {
  background: #f0f7ff;
  padding: 1.2rem;
  border-radius: 6px;
  margin-bottom: 1rem;
}
.scenario-card p {
  margin: 0 0 0.5rem 0;
}
.scenario-card p:last-child {
  margin: 0;
}

/* Decision flow boxes */
.decision-box {
  border-radius: 10px;
  padding: 1.5rem;
  margin-bottom: 1.5rem;
  border-width: 2px;
  border-style: solid;
}
.decision-box h3 {
  margin-top: 0;
}
.decision-box-blue {
  background: #f0f4ff;
  border-color: #2563eb;
}
.decision-box-blue h3 { color: #1e40af; }
.decision-box-green {
  background: #f0faf0;
  border-color: #16a34a;
}
.decision-box-green h3 { color: #15803d; }
.decision-box-amber {
  background: #fffbeb;
  border-color: #d97706;
}
.decision-box-amber h3 { color: #b45309; }
.decision-box-pink {
  background: #fdf2f8;
  border-color: #db2777;
}
.decision-box-pink h3 { color: #be185d; }

/* Combinations cheat sheet callout */
.guide-callout-neutral {
  background: #f8f9fa;
  border: 2px solid #374151;
}

/* Author section */
.author-section {
  margin-top: 2.5rem;
  padding: 1.5rem;
  background: #f8f9fa;
  border-radius: 8px;
  border-left: 4px solid #2563eb;
}
.author-section h3 {
  margin-top: 0;
}
.author-section .author-verification {
  font-size: 0.92rem;
  color: #666;
}

/* Comparison tables */
.guide-table {
  width: 100%;
  border-collapse: collapse;
  margin: 16px 0;
  font-size: 14px;
}

.guide-table th {
  background: rgba(30,64,175,0.25);
  color: var(--text);
  padding: 10px 14px;
  text-align: left;
  font-weight: 600;
  border-bottom: 2px solid rgba(30,64,175,0.5);
}

.guide-table td {
  padding: 10px 14px;
  color: var(--muted);
  border-bottom: 1px solid rgba(30,64,175,0.2);
}

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

.guide-table tr:hover td {
  background: rgba(56,189,248,0.04);
}

/* Visual step section */
.guide-steps-visual {
  margin: 16px 0;
  counter-reset: step-counter;
}

.guide-step {
  display: flex;
  gap: 14px;
  padding: 14px 0;
  border-bottom: 1px solid rgba(30,64,175,0.2);
}

.guide-step:last-child {
  border-bottom: none;
}

.guide-step-num {
  flex-shrink: 0;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: radial-gradient(circle at 30% 20%, #38bdf8, #1d4ed8);
  color: #fff;
  font-weight: 700;
  font-size: 15px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.guide-step-content h4 {
  margin: 0 0 4px;
  font-size: 15px;
  color: var(--text);
}

.guide-step-content p {
  margin: 0;
  font-size: 14px;
  color: var(--muted);
  line-height: 1.6;
}

/* Author section */
.guide-author {
  margin: 28px 0 16px;
  padding: 18px 20px;
  border-radius: 14px;
  background: rgba(15,23,42,0.92);
  border: 1px solid rgba(30,64,175,0.45);
  display: flex;
  gap: 14px;
  align-items: flex-start;
}

.guide-author-avatar {
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: radial-gradient(circle at 30% 20%, #22c55e, #0ea5e9);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 18px;
  color: #fff;
}

.guide-author-info h4 {
  margin: 0 0 2px;
  font-size: 15px;
  color: var(--text);
}

.guide-author-info .author-role {
  font-size: 13px;
  color: var(--accent-blue);
  margin: 0 0 6px;
}

.guide-author-info .author-bio {
  font-size: 13px;
  color: var(--muted);
  line-height: 1.5;
  margin: 0;
}

/* Process flow diagram */
.guide-flow {
  margin: 24px 0;
  padding: 20px 18px;
  border-radius: 14px;
  background: rgba(15,23,42,0.6);
  border: 1px solid rgba(56,189,248,0.25);
}

.guide-flow-title {
  margin: 0 0 14px;
  font-size: 15px;
  color: var(--text);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.guide-flow-steps {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: stretch;
}

.guide-flow-step {
  flex: 1 1 140px;
  min-width: 140px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  position: relative;
  padding-right: 18px;
}

.guide-flow-step:not(:last-child)::after {
  content: "\2192";
  position: absolute;
  right: 0;
  top: 14px;
  color: #38bdf8;
  font-size: 18px;
  font-weight: 700;
}

.guide-flow-node {
  background: radial-gradient(circle at 30% 20%, #38bdf8, #1d4ed8);
  color: #fff;
  padding: 10px 12px;
  border-radius: 10px;
  font-weight: 700;
  font-size: 14px;
  text-align: center;
}

.guide-flow-label {
  font-size: 12.5px;
  color: var(--muted);
  line-height: 1.4;
  text-align: center;
}

@media (max-width: 640px) {
  .guide-flow-steps {
    flex-direction: column;
  }
  .guide-flow-step {
    padding-right: 0;
    padding-bottom: 18px;
  }
  .guide-flow-step:not(:last-child)::after {
    content: "\2193";
    right: 50%;
    transform: translateX(50%);
    top: auto;
    bottom: 0;
  }
}

/* Responsive table scroll */
@media (max-width: 767px) {
  .guide-table-wrap {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }
  .guide-table {
    min-width: 480px;
  }
}

/* Table of contents */

.toc {
  margin: 24px 0;
  padding: 18px 20px;
  background: rgba(15,23,42,0.92);
  border: 1px solid rgba(30,64,175,0.55);
  border-radius: 16px;
}

.toc-heading {
  margin: 0 0 10px;
  font-size: 16px;
  color: var(--text);
  border: none;
  padding-top: 0;
}

.toc-list {
  margin: 0;
  padding-left: 22px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.8;
}

.toc-list a {
  color: var(--accent-blue);
  text-decoration: none;
  transition: color 0.2s ease;
}

.toc-list a:hover {
  color: var(--accent);
  text-decoration: underline;
}

/* FAQ */

details {
  margin-top: 10px;
  padding: 10px 12px;
  border-radius: 14px;
  background: rgba(15,23,42,0.95);
  border: 1px solid rgba(30,64,175,0.7);
}

summary {
  cursor: pointer;
  font-weight: 500;
}

.disclaimer {
  font-size: 13px;
  color: var(--muted);
}

/* Buttons */

.btn {
  border-radius: 999px;
  padding: 9px 16px;
  border: none;
  cursor: pointer;
  font-size: 14px;
  font-weight: 500;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
}

.btn-primary {
  background: radial-gradient(circle at 10% 0, #22c55e, #16a34a 40%, #0ea5e9 100%);
  color: #0b1120;
  box-shadow: 0 14px 35px rgba(15,118,110,0.9);
}

.btn-secondary {
  background: rgba(15,23,42,0.9);
  color: var(--text);
  border: 1px solid rgba(148,163,184,0.6);
}

.btn-full {
  width: 100%;
  max-width: 100%;
}

/* Footer */

.site-footer {
  margin-top: 30px;
  padding: 18px 0 4px;
  font-size: 12px;
  color: var(--muted);
}

.legal-small {
  font-size: 11px;
}

/* Chat page - ChatGPT-style full-height layout */

.chat-main {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 72px 8px 8px;
  height: 100vh;
  display: flex;
  flex-direction: column;
}

.ai-helper-shell {
  display: flex;
  flex-direction: column;
  height: 100%;
  background: linear-gradient(145deg, rgba(15,23,42,0.98), rgba(2,6,23,0.98));
  border-radius: 18px;
  box-shadow: var(--shadow-soft);
  border: 1px solid rgba(30,64,175,0.7);
  overflow: hidden;
}

.ai-header {
  padding: 12px 16px;
  border-bottom: 1px solid rgba(255,255,255,0.08);
  flex-shrink: 0;
}

.ai-header h1 {
  margin: 0 0 4px 0;
  font-size: 18px;
  font-weight: 600;
}

.ai-header p {
  margin: 4px 0 0 0;
  font-size: 13px;
  color: var(--muted);
  line-height: 1.4;
}

.ai-warning {
  margin-top: 6px !important;
  font-size: 11px !important;
  color: #fbbf24 !important;
  line-height: 1.3 !important;
}

.ai-disclaimer {
  margin-top: 8px;
  padding: 10px 12px;
  border: 1px solid rgba(251, 191, 36, 0.35);
  background: rgba(251, 191, 36, 0.08);
  border-radius: 6px;
  font-size: 12px;
  color: #fde68a;
  line-height: 1.45;
}

.ai-disclaimer strong {
  color: #fbbf24;
}

.ai-messages {
  flex: 1;
  overflow-y: auto;
  padding: 12px 16px;
  scroll-behavior: smooth;
}

.chat-message {
  margin-bottom: 12px;
  display: flex;
}

.chat-message.user {
  justify-content: flex-end;
}

.chat-bubble {
  max-width: 85%;
  padding: 10px 14px;
  border-radius: 16px;
  font-size: 14px;
  line-height: 1.5;
}

.chat-message.user .chat-bubble {
  background: radial-gradient(circle at 10% 0, #22c55e, #16a34a 40%, #0ea5e9 100%);
  color: #02101c;
}

.chat-message.assistant .chat-bubble {
  background: rgba(15,23,42,0.96);
  border: 1px solid rgba(30,64,175,0.9);
  color: var(--text);
}

.ai-input {
  border-top: 1px solid rgba(255,255,255,0.08);
  padding: 10px 12px 12px;
  display: flex;
  gap: 8px;
  align-items: flex-end;
  flex-shrink: 0;
}

.ai-input textarea {
  flex: 1;
  resize: none;
  min-height: 42px;
  max-height: 150px;
  padding: 10px 12px;
  border-radius: 12px;
  border: 1px solid rgba(55,65,81,0.85);
  background: rgba(2,6,23,0.96);
  color: var(--text);
  font-size: 14px;
  font-family: inherit;
}

.ai-input .btn {
  flex-shrink: 0;
  padding: 10px 18px;
}

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

/* Affiliate links */

.affiliate-link {
  color: #38bdf8;
  text-decoration: underline;
  font-weight: 500;
  transition: all 0.2s ease;
}

.affiliate-link:hover {
  color: #22c55e;
  text-decoration: none;
  text-shadow: 0 0 8px rgba(56, 189, 248, 0.5);
}

/* Responsive tweaks */

/* Mobile-first: stacked header for small screens */
@media (max-width: 767px) {
  .site-header {
    padding: 8px 12px;
  }

  .header-content {
    flex-direction: column;
    align-items: center;
    gap: 10px;
  }

  .brand {
    width: 100%;
    justify-content: center;
    gap: 8px;
  }

  .brand-title {
    font-size: 14px;
  }

  .brand-subtitle {
    font-size: 10px;
  }

  .nav {
    width: 100%;
    justify-content: center;
    gap: 4px;
    font-size: 12px;
  }

  .nav-link {
    padding: 5px 8px;
    font-size: 12px;
  }

  main {
    padding-top: 108px;
  }

  .chat-main {
    padding-top: 110px;
    padding-left: 4px;
    padding-right: 4px;
  }

  .ai-header h1 {
    font-size: 16px;
  }

  .ai-header p {
    font-size: 12px;
  }

  .ai-warning {
    font-size: 10px !important;
  }

  .ai-messages {
    padding: 10px 12px;
  }

  .chat-bubble {
    max-width: 90%;
    font-size: 13px;
  }
}

@media (min-width: 720px) {
  .hero {
    padding: 28px 28px 28px;
  }

  .hero h1 {
    font-size: 32px;
  }

  .nav {
    gap: 10px;
  }

  .nav-link {
    font-size: 14px;
  }

  main {
    padding-top: 96px;
  }

  .chat-main {
    padding-top: 80px;
  }

  .ai-header h1 {
    font-size: 20px;
  }

  .ai-messages {
    padding: 16px 20px;
  }

  .ai-input {
    padding: 12px 16px 14px;
  }
}