/* ==========================================================================
   BLOG PAGE — styles/blog.css
   Hero · UNC · Topics · Possible Worlds · Logic & Code · CTA
   ========================================================================== */

/* --------------------------------------------------------------------------
   HERO
   -------------------------------------------------------------------------- */
.blog-hero {
  background: linear-gradient(to bottom, var(--background-primary), var(--background-secondary));
  padding: 5rem 2rem 4rem;
  position: relative;
  overflow: hidden;
  text-align: center;
}

.blog-hero-orb {
  position: absolute;
  top: -120px;
  left: 30%;
  transform: translateX(-50%);
  width: 700px;
  height: 450px;
  background: radial-gradient(ellipse, rgba(95, 45, 241, 0.1) 0%, transparent 65%);
  pointer-events: none;
}

.blog-hero-orb--right {
  left: auto;
  right: -100px;
  top: -60px;
  width: 400px;
  height: 300px;
  background: radial-gradient(ellipse, rgba(199, 120, 221, 0.07) 0%, transparent 65%);
}

.blog-hero .section-tag {
  font-family: var(--font-mono);
  font-size: 0.88rem;
  color: var(--color-accent);
  margin-bottom: 1.2rem;
  display: block;
}

.blog-hero h1 {
  font-size: clamp(2.4rem, 5vw, 4rem);
  font-weight: 700;
  margin-bottom: 1.2rem;
  line-height: 1.1;
}

.blog-hero-subtitle {
  font-size: 1.15rem;
  max-width: 600px;
  margin: 0 auto 2.5rem;
  color: var(--color-light-grey);
  line-height: 1.7;
}

.blog-hero-symbols {
  display: flex;
  gap: 1.5rem;
  justify-content: center;
  flex-wrap: wrap;
}

.blog-hero-symbols span {
  font-family: var(--font-mono);
  font-size: 1.6rem;
  color: var(--color-purple);
  opacity: 0.5;
  animation: symbolFloat 4s ease-in-out infinite;
}

.blog-hero-symbols span:nth-child(2) { animation-delay: 0.5s; color: var(--color-pink); }
.blog-hero-symbols span:nth-child(3) { animation-delay: 1s; }
.blog-hero-symbols span:nth-child(4) { animation-delay: 1.5s; color: var(--color-accent); opacity: 0.4; }
.blog-hero-symbols span:nth-child(5) { animation-delay: 2s; }
.blog-hero-symbols span:nth-child(6) { animation-delay: 2.5s; color: var(--color-pink); }
.blog-hero-symbols span:nth-child(7) { animation-delay: 3s; }
.blog-hero-symbols span:nth-child(8) { animation-delay: 3.5s; color: var(--color-accent); opacity: 0.4; }

@keyframes symbolFloat {
  0%, 100% { transform: translateY(0); opacity: 0.4; }
  50% { transform: translateY(-6px); opacity: 0.7; }
}

/* --------------------------------------------------------------------------
   SECTION TAGS (shared)
   -------------------------------------------------------------------------- */
.section-tag {
  font-family: var(--font-mono);
  font-size: 0.88rem;
  color: var(--color-accent);
  margin-bottom: 0.75rem;
  display: block;
}

/* --------------------------------------------------------------------------
   UNC INTRO
   -------------------------------------------------------------------------- */
.unc-section {
  background: var(--background-secondary);
}

.unc-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 5rem;
  align-items: center;
}

.unc-text .section-tag { margin-bottom: 0.8rem; }

.unc-text h2 {
  font-size: clamp(1.8rem, 3vw, 2.5rem);
  font-weight: 700;
  margin-bottom: 1.5rem;
}

.unc-text p {
  margin-bottom: 1.1rem;
  line-height: 1.75;
}

.unc-text p strong {
  color: var(--color-white);
}

.unc-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-top: 1.5rem;
}

/* Credential card */
.credential-card {
  background: rgba(99, 108, 113, 0.06);
  border: 1px solid rgba(95, 45, 241, 0.2);
  border-radius: var(--radius-md);
  padding: 2.5rem 2rem;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  position: relative;
  overflow: hidden;
  box-shadow: 0 8px 40px rgba(95, 45, 241, 0.1);
  transition: transform var(--transition-base), box-shadow var(--transition-base);
}

.credential-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: var(--gradient-primary);
}

.credential-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 16px 50px rgba(95, 45, 241, 0.18);
}

.credential-logo {
  display: flex;
  align-items: center;
  justify-content: center;
}

.credential-logo-inner {
  width: 80px;
  height: 80px;
  background: var(--gradient-primary);
  border-radius: 50%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  box-shadow: 0 0 30px rgba(95, 45, 241, 0.4);
}

.credential-logo-text {
  font-family: var(--font-display);
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--color-white);
  line-height: 1;
}

.credential-logo-sub {
  font-family: var(--font-mono);
  font-size: 0.55rem;
  color: rgba(255, 255, 255, 0.7);
  letter-spacing: 0.02em;
}

.credential-info {
  text-align: center;
}

.credential-title {
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 600;
  color: var(--color-white);
  margin-bottom: 0.4rem;
  line-height: 1.3;
}

.credential-institution {
  font-family: var(--font-sans);
  font-size: 0.95rem;
  color: var(--color-light-grey);
  margin-bottom: 0.3rem;
}

.credential-location {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--color-purple);
  margin-bottom: 1rem;
}

.credential-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: rgba(100, 255, 218, 0.08);
  border: 1px solid rgba(100, 255, 218, 0.2);
  color: var(--color-accent);
  font-family: var(--font-mono);
  font-size: 0.76rem;
  padding: 0.35rem 0.9rem;
  border-radius: var(--radius-pill);
}

.credential-badge-dot {
  width: 6px;
  height: 6px;
  background: var(--color-accent);
  border-radius: 50%;
  animation: pulse 2s infinite;
}

.credential-footer {
  display: flex;
  justify-content: space-around;
  border-top: 1px solid rgba(99, 108, 113, 0.15);
  padding-top: 1.2rem;
}

.credential-stat {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.2rem;
}

.credential-stat-num {
  font-family: var(--font-display);
  font-size: 1.4rem;
  font-weight: 700;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.credential-stat-label {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--color-light-grey);
}

/* --------------------------------------------------------------------------
   TOPICS GRID
   -------------------------------------------------------------------------- */
.topics-section {
  background: var(--background-primary);
}

.topics-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.5rem;
}

.topic-card {
  background: rgba(99, 108, 113, 0.06);
  border: 1px solid rgba(99, 108, 113, 0.12);
  border-radius: var(--radius-md);
  padding: 1.8rem;
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
  transition: border-color var(--transition-base), transform var(--transition-base), box-shadow var(--transition-base);
  position: relative;
  overflow: hidden;
}

.topic-card::after {
  content: '';
  position: absolute;
  bottom: 0; left: 0; right: 0;
  height: 2px;
  background: var(--gradient-primary);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition-base);
}

.topic-card:hover {
  border-color: rgba(95, 45, 241, 0.3);
  transform: translateY(-3px);
  box-shadow: 0 10px 35px rgba(95, 45, 241, 0.1);
}

.topic-card:hover::after {
  transform: scaleX(1);
}

.topic-card-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
}

.topic-icon {
  font-size: 2rem;
  line-height: 1;
  color: var(--color-purple);
}

.topic-number {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: rgba(95, 45, 241, 0.4);
  font-weight: 600;
}

.topic-card h3 {
  font-family: var(--font-display);
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--color-white);
  margin: 0;
  line-height: 1.3;
}

.topic-subtitle {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  color: var(--color-accent);
  margin: 0;
}

.topic-desc {
  font-family: var(--font-sans);
  font-size: 0.88rem;
  color: var(--color-light-grey);
  line-height: 1.65;
  margin: 0;
  flex: 1;
}

.topic-example {
  background: rgba(0, 0, 0, 0.2);
  border: 1px solid rgba(99, 108, 113, 0.1);
  border-radius: var(--radius-sm);
  padding: 1rem;
  margin-top: 0.5rem;
}

.topic-example-label {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--color-accent);
  margin-bottom: 0.6rem;
}

/* Formula styles */
.topic-formula {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
}

.formula-line {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--color-light-grey);
}

.formula-main {
  color: var(--color-white);
  font-size: 0.9rem;
}

.formula-conclusion {
  color: var(--color-accent);
  border-top: 1px solid rgba(99, 108, 113, 0.2);
  padding-top: 0.3rem;
  margin-top: 0.2rem;
}

.formula-comment {
  color: rgba(171, 178, 191, 0.5);
  font-size: 0.76rem;
}

.formula-label {
  color: var(--color-pink);
}

.formula-op {
  color: var(--color-accent);
  font-weight: 600;
}

/* Truth table */
.truth-table {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
}

.truth-table-row {
  display: flex;
  gap: 1rem;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  padding: 0.25rem 0;
}

.truth-table-head {
  color: var(--color-light-grey);
  border-bottom: 1px solid rgba(99, 108, 113, 0.2);
  padding-bottom: 0.3rem;
  margin-bottom: 0.1rem;
}

.truth-table-row span {
  min-width: 30px;
  text-align: center;
}

.tt-true { color: var(--color-accent); }
.tt-false { color: #FF6B6B; }
.tt-indeterminate { color: var(--color-yellow, #FFE66D); }

/* --------------------------------------------------------------------------
   POSSIBLE WORLDS SECTION
   -------------------------------------------------------------------------- */
.worlds-section {
  background: var(--background-secondary);
}

/* Intro */
.worlds-intro {
  max-width: 800px;
  margin: 0 auto 4rem;
  background: rgba(99, 108, 113, 0.05);
  border: 1px solid rgba(95, 45, 241, 0.15);
  border-radius: var(--radius-md);
  padding: 2.5rem;
}

.worlds-intro-text > p {
  font-family: var(--font-sans);
  font-size: 1rem;
  color: var(--color-light-grey);
  margin-bottom: 1.5rem;
  line-height: 1.75;
}

.worlds-intro-text > p:last-child { margin-bottom: 0; }

.modal-ops {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
  margin: 1.5rem 0;
}

.modal-op {
  display: flex;
  gap: 1rem;
  align-items: flex-start;
  background: rgba(0, 0, 0, 0.2);
  border-radius: var(--radius-sm);
  padding: 1.2rem;
  border: 1px solid rgba(95, 45, 241, 0.1);
}

.modal-op-symbol {
  font-family: var(--font-mono);
  font-size: 2.5rem;
  color: var(--color-purple);
  line-height: 1;
  flex-shrink: 0;
  text-shadow: 0 0 20px rgba(95, 45, 241, 0.5);
}

.modal-op-symbol--teal {
  color: var(--color-accent);
  text-shadow: 0 0 20px rgba(100, 255, 218, 0.4);
}

.modal-op strong {
  display: block;
  font-family: var(--font-display);
  font-size: 0.95rem;
  color: var(--color-white);
  margin-bottom: 0.4rem;
}

.modal-op p {
  font-family: var(--font-sans);
  font-size: 0.85rem;
  color: var(--color-light-grey);
  margin: 0;
  line-height: 1.6;
}

.modal-op em {
  color: var(--color-accent);
  font-style: normal;
}

.worlds-intro-text > p em {
  color: var(--color-pink);
  font-style: normal;
}

/* Diagram grid */
.diagrams-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
  margin-bottom: 4rem;
}

.diagram-card {
  background: rgba(99, 108, 113, 0.05);
  border: 1px solid rgba(95, 45, 241, 0.15);
  border-radius: var(--radius-md);
  padding: 2rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
}

.diagram-card:hover {
  border-color: rgba(95, 45, 241, 0.35);
  box-shadow: 0 8px 35px rgba(95, 45, 241, 0.1);
}

.diagram-card--wide {
  grid-column: 1 / -1;
}

.diagram-title {
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--color-white);
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.diagram-label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  background: var(--gradient-primary);
  color: var(--color-white);
  padding: 0.2rem 0.6rem;
  border-radius: var(--radius-sm);
  flex-shrink: 0;
}

.diagram-desc {
  font-family: var(--font-sans);
  font-size: 0.88rem;
  color: var(--color-light-grey);
  line-height: 1.65;
  margin: 0;
}

.diagram-svg-wrapper {
  background: rgba(0, 0, 0, 0.25);
  border-radius: var(--radius-sm);
  border: 1px solid rgba(99, 108, 113, 0.1);
  overflow: hidden;
}

.diagram-svg-wrapper svg {
  width: 100%;
  height: auto;
  display: block;
}

.diagram-svg-wrapper--wide svg {
  width: 100%;
}

.diagram-note {
  display: flex;
  gap: 0.75rem;
  align-items: flex-start;
  background: rgba(95, 45, 241, 0.06);
  border-left: 3px solid var(--color-purple);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  padding: 0.9rem 1rem;
}

.diagram-note-icon {
  font-family: var(--font-mono);
  font-size: 1.1rem;
  color: var(--color-purple);
  flex-shrink: 0;
  margin-top: 0.1rem;
}

.diagram-note p {
  font-family: var(--font-sans);
  font-size: 0.84rem;
  color: var(--color-light-grey);
  margin: 0;
  line-height: 1.65;
}

.diagram-note p em {
  color: var(--color-accent);
  font-style: normal;
}

/* Exercises */
.exercises-section {
  margin-top: 1rem;
}

.exercises-title {
  font-family: var(--font-display);
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--color-white);
  margin-bottom: 2rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.exercises-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.exercise-card {
  background: rgba(99, 108, 113, 0.06);
  border: 1px solid rgba(99, 108, 113, 0.12);
  border-radius: var(--radius-md);
  padding: 1.8rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  transition: border-color var(--transition-base), transform var(--transition-base);
}

.exercise-card:hover {
  border-color: rgba(100, 255, 218, 0.2);
  transform: translateY(-3px);
}

.exercise-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.exercise-num {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--color-accent);
  font-weight: 600;
}

.exercise-difficulty {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  background: rgba(100, 255, 218, 0.1);
  border: 1px solid rgba(100, 255, 218, 0.2);
  color: var(--color-accent);
  padding: 0.2rem 0.6rem;
  border-radius: var(--radius-pill);
}

.exercise-difficulty--medium {
  background: rgba(199, 120, 221, 0.1);
  border-color: rgba(199, 120, 221, 0.2);
  color: var(--color-pink);
}

.exercise-difficulty--hard {
  background: rgba(95, 45, 241, 0.1);
  border-color: rgba(95, 45, 241, 0.2);
  color: #987af0;
}

.exercise-q {
  font-family: var(--font-sans);
  font-size: 0.9rem;
  color: var(--color-light-grey);
  line-height: 1.65;
  margin: 0;
}

.exercise-q strong {
  color: var(--color-white);
}

.exercise-work {
  background: rgba(0, 0, 0, 0.25);
  border-radius: var(--radius-sm);
  padding: 0.9rem 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
}

.exercise-step {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: rgba(171, 178, 191, 0.7);
  margin: 0;
}

.exercise-answer {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.exercise-answer-label {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--color-light-grey);
}

.exercise-answer-val {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--color-accent);
  background: rgba(100, 255, 218, 0.08);
  padding: 0.2rem 0.6rem;
  border-radius: var(--radius-sm);
  border: 1px solid rgba(100, 255, 218, 0.15);
}

.exercise-answer-val--false {
  color: #FF6B6B;
  background: rgba(255, 107, 107, 0.08);
  border-color: rgba(255, 107, 107, 0.15);
}

.exercise-explain {
  font-family: var(--font-sans);
  font-size: 0.84rem;
  color: var(--color-light-grey);
  line-height: 1.65;
  margin: 0;
  border-top: 1px solid rgba(99, 108, 113, 0.15);
  padding-top: 0.8rem;
}

/* --------------------------------------------------------------------------
   LOGIC & CODE
   -------------------------------------------------------------------------- */
.logic-code-section {
  background: var(--background-primary);
}

.logic-code-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
}

.logic-code-card {
  background: rgba(99, 108, 113, 0.06);
  border: 1px solid rgba(99, 108, 113, 0.12);
  border-radius: var(--radius-md);
  padding: 1.8rem;
  display: flex;
  gap: 1.2rem;
  align-items: flex-start;
  transition: border-color var(--transition-base), transform var(--transition-base), box-shadow var(--transition-base);
}

.logic-code-card:hover {
  border-color: rgba(95, 45, 241, 0.25);
  transform: translateY(-3px);
  box-shadow: 0 10px 35px rgba(95, 45, 241, 0.08);
}

.logic-code-icon {
  width: 44px;
  height: 44px;
  background: rgba(95, 45, 241, 0.1);
  border: 1px solid rgba(95, 45, 241, 0.2);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  color: var(--color-purple);
}

.logic-code-icon svg {
  width: 20px;
  height: 20px;
}

.logic-code-content {
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
  flex: 1;
  min-width: 0;
}

.logic-code-mapping {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.logic-code-from {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--color-pink);
  font-weight: 500;
}

.logic-code-arrow {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--color-light-grey);
}

.logic-code-to {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--color-accent);
  font-weight: 500;
}

.logic-code-content > p {
  font-family: var(--font-sans);
  font-size: 0.88rem;
  color: var(--color-light-grey);
  line-height: 1.7;
  margin: 0;
}

.logic-code-snippet {
  background: rgba(0, 0, 0, 0.3);
  border-radius: var(--radius-sm);
  padding: 0.9rem 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
  border: 1px solid rgba(99, 108, 113, 0.1);
}

.snippet-comment {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  color: rgba(171, 178, 191, 0.5);
  display: block;
}

.snippet-code {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--color-accent);
  display: block;
  word-break: break-all;
}

/* --------------------------------------------------------------------------
   CTA
   -------------------------------------------------------------------------- */
.blog-cta {
  background: var(--background-secondary);
}

.blog-cta-banner {
  position: relative;
  overflow: hidden;
}

.cta-banner-symbols {
  position: absolute;
  top: 1.5rem;
  right: 2rem;
  display: flex;
  gap: 1rem;
  pointer-events: none;
}

.cta-banner-symbols span {
  font-family: var(--font-mono);
  font-size: 2rem;
  color: var(--color-purple);
  opacity: 0.08;
}

.blog-cta-banner .section-tag {
  margin-bottom: 0.75rem;
}

.blog-cta-banner h2 {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  margin-bottom: 0.9rem;
}

.blog-cta-banner > p {
  font-size: 1rem;
  max-width: 540px;
  margin: 0 auto 2rem;
  line-height: 1.7;
}

/* --------------------------------------------------------------------------
   REVEAL ANIMATION STATES
   -------------------------------------------------------------------------- */
[data-reveal] {
  opacity: 0;
  transform: translateY(30px);
}

[data-reveal="left"] {
  opacity: 0;
  transform: translateX(-30px);
}

[data-reveal="right"] {
  opacity: 0;
  transform: translateX(30px);
}

/* --------------------------------------------------------------------------
   RESPONSIVE
   -------------------------------------------------------------------------- */
@media (max-width: 1024px) {
  .exercises-grid {
    grid-template-columns: 1fr 1fr;
  }

  .exercises-grid .exercise-card:last-child {
    grid-column: 1 / -1;
  }
}

@media (max-width: 900px) {
  .unc-grid {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }

  .diagrams-grid {
    grid-template-columns: 1fr;
  }

  .diagram-card--wide {
    grid-column: auto;
  }

  .logic-code-grid {
    grid-template-columns: 1fr;
  }

  .modal-ops {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .topics-grid {
    grid-template-columns: 1fr;
  }

  .exercises-grid {
    grid-template-columns: 1fr;
  }

  .exercises-grid .exercise-card:last-child {
    grid-column: auto;
  }

  .logic-code-card {
    flex-direction: column;
  }

  .blog-hero-symbols span {
    font-size: 1.2rem;
  }

  .worlds-intro {
    padding: 1.5rem;
  }
}

@media (max-width: 480px) {
  .blog-hero {
    padding: 3.5rem 1rem 3rem;
  }

  .credential-footer {
    flex-wrap: wrap;
    gap: 1rem;
  }

  .cta-banner-symbols {
    display: none;
  }
}