/* ============================================================
   CPA AI Strategy Research Packet — adapted from
   calvaryonlineschool.com brand colors and typography.
   ============================================================ */

:root {
  /* CPA palette (from their site) */
  --cpa-teal: #226d7a;
  --cpa-teal-dark: #1a5862;
  --cpa-sky: #22b8d1;
  --cpa-cloud: #b0e0e9;
  --cpa-ivory: #e4f5fa;
  --cpa-white: #ffffff;

  /* Typography */
  --cpa-text: #1a1a1a;
  --cpa-text-soft: #4a5a60;
  --cpa-text-muted: #6e7e83;
  --cpa-border: #d6e6ea;
  --cpa-border-strong: #b0e0e9;

  /* Layout */
  --max-content: 740px;
  --max-page: 1240px;
  --header-h: 84px;

  /* Type */
  --font-display: "Roboto", "Helvetica Neue", Arial, sans-serif;
  --font-body: "Open Sans", "Helvetica Neue", Arial, sans-serif;
}

* {
  box-sizing: border-box;
  -webkit-tap-highlight-color: transparent;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  padding: 0;
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.7;
  color: var(--cpa-text);
  background: var(--cpa-white);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  color: var(--cpa-teal);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.15s ease, color 0.15s ease;
}

a:hover {
  color: var(--cpa-sky);
  border-bottom-color: var(--cpa-sky);
}

/* ============== HEADER ================== */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--cpa-white);
  border-bottom: 1px solid var(--cpa-border);
  height: var(--header-h);
  backdrop-filter: blur(8px);
  box-shadow: 0 1px 4px rgba(34, 109, 122, 0.04);
}

.header-inner {
  max-width: var(--max-page);
  height: 100%;
  margin: 0 auto;
  padding: 0 32px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.logo-link {
  border: none;
  display: flex;
  align-items: center;
}

.logo-link img {
  height: 52px;
  width: auto;
  display: block;
}

@media (max-width: 700px) {
  .logo-link img {
    height: 40px;
  }
  :root {
    --header-h: 68px;
  }
}

.primary-nav {
  display: flex;
  gap: 28px;
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 15px;
}

.primary-nav a {
  color: var(--cpa-teal);
  border: none;
  padding: 8px 0;
}

.primary-nav a:hover {
  color: var(--cpa-sky);
}

@media (max-width: 700px) {
  .primary-nav {
    gap: 16px;
    font-size: 13px;
  }
  .header-inner {
    padding: 0 20px;
  }
}

/* ============== PAGE LAYOUT ================== */

.page {
  max-width: var(--max-page);
  margin: 0 auto;
  padding: 48px 32px 96px;
}

.page-grid {
  display: grid;
  grid-template-columns: 240px 1fr;
  gap: 56px;
}

@media (max-width: 960px) {
  .page-grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }
  .page {
    padding: 32px 20px 72px;
  }
}

/* TOC sidebar */

.toc {
  position: relative;
}

.toc-inner {
  position: sticky;
  top: calc(var(--header-h) + 32px);
}

.toc-title {
  font-family: var(--font-display);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--cpa-text-muted);
  margin: 0 0 16px;
}

.toc-list {
  list-style: none;
  padding: 0;
  margin: 0;
  font-family: var(--font-display);
  font-size: 14px;
  line-height: 1.45;
}

.toc-list li {
  margin-bottom: 4px;
}

.toc-list a {
  display: block;
  padding: 8px 12px;
  border-radius: 6px;
  color: var(--cpa-text-soft);
  border: none;
  border-left: 3px solid transparent;
  transition: background 0.15s, color 0.15s, border-color 0.15s;
}

.toc-list a:hover {
  background: var(--cpa-ivory);
  color: var(--cpa-teal);
}

.toc-list a.active {
  background: var(--cpa-ivory);
  color: var(--cpa-teal);
  font-weight: 700;
  border-left-color: var(--cpa-sky);
}

.toc-list .brief-link {
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px solid var(--cpa-border);
}

@media (max-width: 960px) {
  .toc-inner {
    position: static;
  }
  .toc {
    background: var(--cpa-ivory);
    padding: 16px;
    border-radius: 12px;
  }
}

/* ============== ARTICLE ================== */

.content {
  max-width: 100%;
  min-width: 0;
}

.article-header {
  margin-bottom: 40px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--cpa-border);
}

.kicker {
  font-family: var(--font-display);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--cpa-sky);
  margin: 0 0 12px;
}

.article-header h1 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 40px;
  line-height: 1.15;
  color: var(--cpa-teal);
  margin: 0 0 12px;
  letter-spacing: -0.01em;
}

.article-header .subtitle {
  font-family: var(--font-display);
  font-weight: 400;
  font-size: 19px;
  line-height: 1.5;
  color: var(--cpa-text-soft);
  margin: 0;
}

@media (max-width: 700px) {
  .article-header h1 {
    font-size: 30px;
  }
  .article-header .subtitle {
    font-size: 17px;
  }
}

/* ============== PROSE ================== */

.prose {
  max-width: var(--max-content);
}

.prose h1,
.prose h2,
.prose h3,
.prose h4 {
  font-family: var(--font-display);
  color: var(--cpa-teal);
  letter-spacing: -0.005em;
}

.prose h1 {
  font-size: 32px;
  line-height: 1.2;
  font-weight: 700;
  margin: 56px 0 16px;
}

.prose h2 {
  font-size: 26px;
  line-height: 1.25;
  font-weight: 700;
  margin: 48px 0 14px;
  padding-top: 8px;
}

.prose h3 {
  font-size: 20px;
  line-height: 1.35;
  font-weight: 700;
  margin: 32px 0 10px;
  color: var(--cpa-teal-dark);
}

.prose h4 {
  font-size: 17px;
  font-weight: 700;
  margin: 24px 0 8px;
  color: var(--cpa-teal-dark);
}

.prose p {
  margin: 0 0 18px;
}

.prose ul,
.prose ol {
  margin: 0 0 20px;
  padding-left: 24px;
}

.prose li {
  margin-bottom: 8px;
}

.prose li > p {
  margin-bottom: 8px;
}

.prose strong {
  color: var(--cpa-teal);
  font-weight: 700;
}

.prose em {
  font-style: italic;
}

.prose blockquote {
  margin: 24px 0;
  padding: 18px 24px;
  background: var(--cpa-ivory);
  border-left: 4px solid var(--cpa-sky);
  border-radius: 0 8px 8px 0;
  font-style: italic;
  color: var(--cpa-teal-dark);
  font-size: 17px;
  line-height: 1.6;
}

.prose blockquote p {
  margin: 0 0 8px;
}

.prose blockquote p:last-child {
  margin: 0;
}

.prose code {
  font-family: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
  font-size: 0.9em;
  background: var(--cpa-ivory);
  padding: 2px 6px;
  border-radius: 4px;
  color: var(--cpa-teal-dark);
}

.prose pre {
  background: var(--cpa-ivory);
  padding: 16px 20px;
  border-radius: 8px;
  overflow-x: auto;
  border: 1px solid var(--cpa-border);
  font-size: 14px;
  line-height: 1.5;
  margin: 20px 0;
}

.prose pre code {
  background: transparent;
  padding: 0;
  border-radius: 0;
}

.prose hr {
  border: none;
  border-top: 1px solid var(--cpa-border);
  margin: 40px 0;
}

.prose table {
  width: 100%;
  border-collapse: collapse;
  margin: 24px 0;
  font-size: 15px;
  border: 1px solid var(--cpa-border);
  border-radius: 8px;
  overflow: hidden;
}

.prose th,
.prose td {
  padding: 10px 14px;
  text-align: left;
  border-bottom: 1px solid var(--cpa-border);
  border-right: 1px solid var(--cpa-border);
}

.prose th:last-child,
.prose td:last-child {
  border-right: none;
}

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

.prose th {
  background: var(--cpa-ivory);
  color: var(--cpa-teal);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 13px;
  letter-spacing: 0.03em;
  text-transform: uppercase;
}

.prose tr:nth-child(even) td {
  background: rgba(228, 245, 250, 0.4);
}

.brief-prose p {
  font-size: 18px;
  line-height: 1.75;
}

/* ============== ARTICLE FOOTER ================== */

.article-footer {
  margin-top: 64px;
  padding-top: 24px;
  border-top: 1px solid var(--cpa-border);
  font-size: 14px;
  color: var(--cpa-text-muted);
  font-family: var(--font-display);
}

.article-footer p {
  margin: 0 0 6px;
}

.article-footer .credit {
  color: var(--cpa-text-soft);
}

/* ============== SITE FOOTER ================== */

.site-footer {
  background: var(--cpa-teal);
  color: var(--cpa-cloud);
  padding: 32px;
  font-family: var(--font-display);
  font-size: 14px;
}

.site-footer .footer-inner {
  max-width: var(--max-page);
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

.site-footer a {
  color: var(--cpa-cloud);
  border-bottom-color: rgba(176, 224, 233, 0.4);
}

.site-footer a:hover {
  color: var(--cpa-white);
  border-bottom-color: var(--cpa-white);
}

.site-footer p {
  margin: 0;
}

@media (max-width: 700px) {
  .site-footer .footer-inner {
    flex-direction: column;
  }
}

/* ============== LANDING PAGE ================== */

body.landing .article-header {
  display: none;
}

.hero {
  background: linear-gradient(135deg, var(--cpa-ivory) 0%, var(--cpa-cloud) 100%);
  padding: 56px 40px;
  border-radius: 16px;
  margin-bottom: 32px;
}

.hero-text {
  max-width: 640px;
}

.hero-kicker {
  font-family: var(--font-display);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--cpa-teal);
  margin: 0 0 12px;
}

.hero-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 38px;
  line-height: 1.18;
  color: var(--cpa-teal);
  margin: 0 0 16px;
  letter-spacing: -0.015em;
}

.hero-lede {
  font-family: var(--font-display);
  font-weight: 400;
  font-size: 18px;
  line-height: 1.55;
  color: var(--cpa-teal-dark);
  margin: 0 0 28px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 26px;
  border-radius: 10px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 15px;
  letter-spacing: 0.005em;
  border: 2px solid transparent;
  cursor: pointer;
  transition: transform 0.15s ease, background 0.15s ease, box-shadow 0.15s ease, border-color 0.15s ease, color 0.15s ease;
  text-decoration: none;
  line-height: 1;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn-primary {
  background: var(--cpa-teal);
  color: var(--cpa-white) !important;
  border-color: var(--cpa-teal);
  box-shadow: 0 1px 2px rgba(34, 109, 122, 0.2), 0 4px 12px rgba(34, 109, 122, 0.15);
}

.btn-primary:hover {
  background: var(--cpa-teal-dark);
  border-color: var(--cpa-teal-dark);
  color: var(--cpa-white) !important;
  box-shadow: 0 2px 4px rgba(34, 109, 122, 0.25), 0 8px 20px rgba(34, 109, 122, 0.2);
}

.btn-secondary {
  background: var(--cpa-white);
  color: var(--cpa-teal) !important;
  border-color: var(--cpa-teal);
  box-shadow: 0 1px 2px rgba(34, 109, 122, 0.06);
}

.btn-secondary:hover {
  background: var(--cpa-ivory);
  color: var(--cpa-teal-dark) !important;
  border-color: var(--cpa-teal-dark);
  box-shadow: 0 1px 2px rgba(34, 109, 122, 0.1), 0 4px 8px rgba(34, 109, 122, 0.08);
}

@media (max-width: 700px) {
  .hero {
    padding: 36px 24px;
  }
  .hero-title {
    font-size: 28px;
  }
  .hero-lede {
    font-size: 16px;
  }
}

/* ============== AUDIO CARD ================== */

.audio-card {
  background: var(--cpa-ivory);
  border: 1px solid var(--cpa-border-strong);
  border-radius: 12px;
  padding: 28px 32px;
  margin-bottom: 32px;
}

.audio-card h2 {
  font-family: var(--font-display);
  color: var(--cpa-teal);
  font-size: 22px;
  margin: 0 0 8px;
}

.audio-card p {
  margin: 0 0 16px;
  color: var(--cpa-text-soft);
}

.audio-card audio {
  width: 100%;
  margin-bottom: 8px;
}

.audio-meta {
  font-size: 13px;
  color: var(--cpa-text-muted);
  font-family: var(--font-display);
}

@media (max-width: 700px) {
  .audio-card {
    padding: 20px 18px;
  }
}

/* ============== CONTENTS LIST ================== */

.contents {
  margin-bottom: 32px;
}

.contents h2 {
  font-family: var(--font-display);
  color: var(--cpa-teal);
  font-size: 24px;
  margin: 0 0 12px;
}

.contents > p {
  color: var(--cpa-text-soft);
  margin-bottom: 24px;
}

.contents-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 12px;
}

.contents-list li a {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  padding: 18px 22px;
  background: var(--cpa-white);
  border: 1px solid var(--cpa-border);
  border-radius: 10px;
  color: var(--cpa-text);
  border-bottom-color: var(--cpa-border);
  transition: all 0.15s;
  height: 100%;
}

.contents-list li a:hover {
  border-color: var(--cpa-sky);
  background: var(--cpa-ivory);
  transform: translateY(-1px);
}

.contents-list .num {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 14px;
  color: var(--cpa-sky);
  letter-spacing: 0.05em;
  flex-shrink: 0;
  width: 32px;
  padding-top: 2px;
}

.contents-list .meta {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.contents-list strong {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 16px;
  color: var(--cpa-teal);
}

.contents-list em {
  font-style: normal;
  font-size: 14px;
  color: var(--cpa-text-muted);
  line-height: 1.45;
}

/* ============== HOW TO READ ================== */

.how-to-read {
  background: var(--cpa-white);
  border: 1px solid var(--cpa-border);
  border-radius: 12px;
  padding: 28px 32px;
}

.how-to-read h2 {
  font-family: var(--font-display);
  color: var(--cpa-teal);
  font-size: 22px;
  margin: 0 0 16px;
}

.how-to-read ul {
  margin: 0;
  padding-left: 22px;
}

.how-to-read li {
  margin-bottom: 12px;
  color: var(--cpa-text-soft);
}

.how-to-read strong {
  color: var(--cpa-teal);
}

@media (max-width: 700px) {
  .how-to-read {
    padding: 20px 18px;
  }
}

/* ============== PRINT ================== */

@media print {
  .site-header,
  .site-footer,
  .toc,
  .primary-nav {
    display: none;
  }
  .page-grid {
    grid-template-columns: 1fr;
  }
  .page {
    padding: 0;
  }
  .prose {
    max-width: 100%;
  }
  body {
    font-size: 12pt;
    line-height: 1.5;
  }
  .article-header h1 {
    font-size: 24pt;
  }
  .prose h2 {
    font-size: 18pt;
    page-break-after: avoid;
  }
  .prose h3 {
    font-size: 14pt;
    page-break-after: avoid;
  }
  .prose blockquote {
    background: transparent;
    border-left: 3px solid #999;
  }
}