/* ===============================
   ROOT VARIABLES
   =============================== */

:root {
  --primary: #9DC6AE;
  --primary-dark: #6f8f80;
  --text-main: #1f2d2a;
  --text-muted: #6f7f78;
  --border-light: #d8e6df;
  --bg-light: #ffffff;
}

/* ===============================
   GLOBAL RESET
   =============================== */

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI",
               Roboto, Helvetica, Arial, sans-serif;
  color: var(--text-main);
  background: var(--bg-light);
  line-height: 1.7;
}

/* ===============================
   CONTAINER
   =============================== */

.container {
  max-width: 980px;
  margin: 0 auto;
  padding: 32px 20px;
}

/* ===============================
   TYPOGRAPHY
   =============================== */

h1 {
  font-size: 2.2rem;
  color: var(--primary-dark);
  margin-bottom: 10px;
  letter-spacing: -0.01em;
}

h2 {
  font-size: 1.4rem;
  color: var(--primary-dark);
  margin-top: 32px;
  letter-spacing: -0.01em;
}

h3 {
  color: var(--primary-dark);
}

p {
  margin: 10px 0;
}

.muted {
  color: var(--text-muted);
  font-size: 0.95rem;
}

.last-updated {
  font-size: 0.85rem;
  color: var(--primary-dark);
  margin-top: -6px;
  margin-bottom: 20px;
}

/* ===============================
   NAVIGATION
   =============================== */

nav {
  display: flex;
  gap: 24px;
  padding: 16px 20px;
  border-bottom: 1px solid var(--border-light);
  max-width: 980px;
  margin: 0 auto;
}

nav a {
  text-decoration: none;
  color: var(--text-main);
  font-weight: 500;
}

nav a:hover {
  color: var(--primary-dark);
}

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

.footer {
  border-top: 1px solid var(--border-light);
  margin-top: 60px;
}

.footer .container {
  padding: 24px 20px;
  color: var(--text-muted);
  font-size: 0.9rem;
  text-align: center;
}

.footer-tagline {
  font-weight: 600;
  margin-bottom: 12px;
}

/* ===============================
   SEO NAME VARIANTS (HIDDEN)
   =============================== */

.seo-names {
  display: none !important;
  visibility: hidden;
  height: 0;
  overflow: hidden;
}


/* ===============================
   ABOUT PAGE ENHANCEMENTS
   =============================== */

.about-intro {
  max-width: 780px;
  margin-bottom: 32px;
}

.about-highlights {
  display: grid;
  grid-template-columns: 160px 1fr;
  gap: 36px;
  align-items: center;
  margin: 32px 0 40px;
  border-top: 1px solid var(--border-light);
  border-bottom: 1px solid var(--border-light);
  padding: 24px 0;
}


.about-highlights img {
  width: 100%;
   max-width: 170px;
  border-radius: 14px;
  margin-top: 10px;
}


.about-highlights ul {
  margin: 0;
  padding-left: 18px;
}

.about-highlights li {
  margin-bottom: 12px;
  line-height: 1.55;
}

.about-highlights li::marker {
  color: var(--primary-dark);
}


/* ===============================
   TOPIC INDEX GRID
   =============================== */

.topic-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
  margin-top: 32px;
}

.topic-card {
  display: block;
  padding: 22px;
  border: 2px solid var(--primary);
  border-radius: 14px;
  background: rgba(157, 198, 174, 0.06);
  text-decoration: none;
  color: var(--text-main);
  transition: background 0.2s ease, transform 0.2s ease;
}

.topic-card:hover {
  background: rgba(157, 198, 174, 0.14);
  transform: translateY(-2px);
}

.topic-card h3 {
  margin-top: 0;
}

.topic-card span {
  font-weight: 600;
  color: var(--primary-dark);
}

/* ===============================
   ACCORDION (TOPIC PAGES)
   =============================== */

.accordion {
  border: 1.5px solid var(--primary);
  border-radius: 12px;
  margin-top: 24px;
  overflow: hidden;
}

.accordion-header {
  padding: 16px 20px;
  cursor: pointer;
  font-weight: 600;
  color: var(--primary-dark);
  background: rgba(157, 198, 174, 0.08);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.accordion-header:hover {
  background: rgba(157, 198, 174, 0.14);
}

.accordion-content {
  display: none;
  padding: 24px;
  border-top: 1px solid var(--border-light);
}

.accordion.open .accordion-content {
  display: block;
}



/* ===============================
   QUIZ
   =============================== */

.quiz-block {
  padding: 20px;
  margin-bottom: 32px;
  border-radius: 12px;
  background: #ffffff;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.04);
  transition: opacity 0.2s ease;
}

.quiz-block:has(.quiz-feedback:not(.hidden)) {
  opacity: 0.96;
}


.quiz-question {
  font-weight: 600;
  margin-bottom: 12px;
}

.quiz-option {
  display: block;
  width: 100%;
  margin: 8px 0;
  padding: 10px 14px;
  border-radius: 8px;
  border: 1.5px solid var(--primary);
  background: #ffffff;
  text-align: left;
  cursor: pointer;
}

.quiz-option:focus-visible {
  outline: 2px solid var(--primary);
  outline-offset: 2px;
}

.quiz-option:hover {
  background: rgba(157, 198, 174, 0.12);
}

.quiz-option:disabled {
  opacity: 0.45;
  cursor: default;
  border-color: #d9e7df;
}


.quiz-feedback {
  margin-top: 16px;
  padding: 14px 16px;
  border-radius: 10px;
  font-size: 0.95rem;
  line-height: 1.5;
}

.quiz-feedback.correct {
  background: #e6f4ea;
  border: 1px solid #b7e1c2;
  color: #1f5e3b;
}

.quiz-feedback.incorrect {
  background: #fdecea;
  border: 1px solid #f5c2c0;
  color: #7a2e2e;
}

.quiz-feedback.hidden {
  display: none;
}



/* ===============================
   RESPONSIVE
   =============================== */

@media (max-width: 768px) {
  .about-highlights {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .about-highlights img {
    max-width: 220px;
    margin: 0 auto;
    display: block;
  }
}

/* ===============================
   HOME HERO
   =============================== */


.home-hero {
  display: grid;
  grid-template-columns: 1.25fr 0.75fr;
  gap: 56px;
  align-items: flex-start; /* key change */
}

.hero-text h1 {
  margin-bottom: 12px;
}


.hero-points {
  margin: 18px 0;
  padding-left: 18px;
}

.hero-points li {
  margin-bottom: 10px;
}

.hero-points li::marker {
  color: var(--primary-dark);
}

.hero-cta {
  display: inline-block;
  margin-top: 18px;
  padding: 10px 18px;
  border-radius: 8px;
  border: 2px solid var(--primary-dark);
  text-decoration: none;
  color: var(--primary-dark);
  font-weight: 600;
}

.hero-cta:hover {
  background: rgba(157, 198, 174, 0.15);
}

.hero-image img {
  padding-top: 12px;
  width: 100%;
  max-width: 280px;
  border-radius: 16px;
  margin-top: 8px;
}

/* Mobile */
@media (max-width: 768px) {
  .home-hero {
    grid-template-columns: 1fr;
  }

  .hero-image {
    order: -1;
  }

  .hero-image img {
    margin: 0 auto 20px;
    display: block;
    max-width: 240px;
  }
}

/* ===============================
   FLASHCARDS – EXECUTIVE STYLE (CALIBRATED)
   =============================== */

:root {
  --card-shadow: 0 22px 44px rgba(31, 45, 42, 0.18);
}

/* Stage */
.flashcard-stage {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 72px 16px;
  background:
    radial-gradient(circle at left, rgba(157,198,174,0.10), transparent 45%),
    radial-gradient(circle at right, rgba(157,198,174,0.12), transparent 45%);
}

/* Card */
.flashcard {
  width: 100%;
  max-width: 380px;
  min-height: 300px;
  padding: 32px;
  border-radius: 20px;
  box-shadow: var(--card-shadow);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: background 0.25s ease, color 0.25s ease;
  position: relative;
  z-index: 2; /* ensures card sits above glow */
}

/* Question */
.flashcard.question {
  background: #343a38; /* softer charcoal */
  color: #f5f7f6;
}

/* Answer */
.flashcard.answer {
  background: #fdfefe; /* warm white */
  color: #1f2d2a;
}

/* Text */
.flashcard-content {
  font-size: 1.05rem;
  line-height: 1.65;
  letter-spacing: 0.01em;
}

/* Action */
.flashcard-action {
  margin-top: 22px;
  text-align: center;
}

.flashcard-action button {
  background: rgba(255,255,255,0.12);
  border: 1px solid rgba(255,255,255,0.25);
  border-radius: 999px;
  padding: 6px 16px;
  font-size: 0.85rem;
  color: #ffffff;
  cursor: pointer;
}

.flashcard.answer .flashcard-action {
  display: none;
}

/* Nav arrows */
.flashcard-nav {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  width: 40px;
  height: 40px;
  border-radius: 50%;
  border: 1.5px solid rgba(111,143,128,0.35);
  background: rgba(255,255,255,0.85);
  color: var(--primary-dark);
  cursor: pointer;
  z-index: 1;
}

.flashcard-nav.left { left: 12px; }
.flashcard-nav.right { right: 12px; }

.flashcard-nav:hover {
  background: rgba(157,198,174,0.15);
}


/* ===============================
   FLASHCARDS – MOBILE USABILITY
   =============================== */

@media (max-width: 768px) {

  .flashcard-action button {
    padding: 10px 22px;
    font-size: 0.9rem;
  }

  .flashcard-nav {
    width: 44px;
    height: 44px;
  }
}

/* ===============================
   CHANGE LOG
   =============================== */

.changelog-wrapper {
  max-width: 900px;
  margin: 0 auto;
  padding: 48px 20px 64px;
}

.changelog-header h1 {
  margin-bottom: 8px;
}

.changelog-header p {
  color: #6b7f76;
  margin-bottom: 40px;
}

.changelog-entry {
  padding: 24px 0;
  border-top: 1px solid #e4efe9;
}

.changelog-entry:first-of-type {
  border-top: none;
}

.changelog-entry h3 {
  margin-bottom: 6px;
  font-size: 1.05rem;
}

.changelog-meta {
  font-size: 0.85rem;
  color: #6b7f76;
  margin-bottom: 14px;
}

.changelog-section-title {
  font-weight: 600;
  margin-top: 14px;
  margin-bottom: 6px;
}

.changelog-entry ul {
  margin: 6px 0 0 18px;
}

.changelog-entry li {
  margin-bottom: 6px;
}

/* ===============================
   FOOTER LINKS
   =============================== */

.footer a {
  color: #6b7f76;            /* same muted tone */
  text-decoration: none;
}

.footer a:hover {
  color: var(--primary);     /* your green */
  text-decoration: underline;
}