:root {
  --color-paper: #FDFCF8;
  --color-ink: #0B2144;
  --color-ink-light: #1E3F7A;
  --color-accent: #E35D5D;
  --color-border: #E5E1D8;
  --color-spine-1: #3B5B82;
  --color-spine-2: #849378;
  --color-spine-3: #D4A373;
  
  --shadow-book: 5px 5px 15px rgba(11, 33, 68, 0.08);
  --radius-sm: 4px;
}

body {
  background-color: var(--color-paper);
  color: var(--color-ink);
  font-family: 'Lora', serif; /* Editorial serif feel */
  background-image: 
    linear-gradient(var(--color-border) 1px, transparent 1px),
    linear-gradient(90deg, var(--color-border) 1px, transparent 1px);
  background-size: 40px 40px;
  background-position: -1px -1px;
}

.hero {
  padding: 6rem 1rem 4rem;
  max-width: 1200px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: center;
}

.hero-content h1 {
  font-size: clamp(2.5rem, 5vw, 4rem);
  font-family: 'Be Vietnam Pro', sans-serif;
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.03em;
  margin-bottom: 1.5rem;
}

.hero-content p {
  font-size: 1.25rem;
  color: var(--color-ink-light);
  line-height: 1.7;
  margin-bottom: 2.5rem;
  max-width: 500px;
}

/* Bookshelf Metaphor */
.hero-visual {
  position: relative;
  display: flex;
  align-items: flex-end;
  gap: 1rem;
  height: 350px;
  padding-bottom: 1rem;
  border-bottom: 12px solid var(--color-ink);
}

.book-spine {
  width: 60px;
  height: 250px;
  background: var(--color-spine-1);
  border-radius: var(--radius-sm);
  box-shadow: inset -4px 0 10px rgba(0,0,0,0.1), var(--shadow-book);
  position: relative;
  transition: transform 0.3s;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  padding: 1rem 0;
  color: white;
  align-items: center;
}

.book-spine:hover {
  transform: translateY(-10px);
}

.book-spine.taller { height: 300px; background: var(--color-spine-2); }
.book-spine.shorter { height: 220px; background: var(--color-spine-3); }

.book-code {
  font-family: monospace;
  font-size: 0.75rem;
  opacity: 0.7;
  writing-mode: vertical-rl;
}

.book-title {
  writing-mode: vertical-rl;
  font-family: 'Be Vietnam Pro', sans-serif;
  font-weight: 700;
  font-size: 1.1rem;
  letter-spacing: 1px;
}

/* Feature grid */
.features {
  max-width: 1200px;
  margin: 0 auto 6rem;
  padding: 0 1rem;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
}

.feature-card {
  background: white;
  padding: 2.5rem 2rem;
  border: 1px solid var(--color-border);
  position: relative;
  box-shadow: var(--shadow-book);
}

.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: var(--color-ink);
}

.feature-card h3 {
  font-family: 'Be Vietnam Pro', sans-serif;
  font-size: 1.25rem;
  font-weight: 700;
  margin: 1rem 0 0.5rem;
}

.feature-card p {
  color: var(--color-ink-light);
  line-height: 1.6;
}

.btn-primary {
  background: var(--color-ink);
  color: white;
  padding: 1rem 2rem;
  font-family: 'Be Vietnam Pro', sans-serif;
  font-weight: 600;
  text-decoration: none;
  display: inline-block;
  border-radius: var(--radius-sm);
  transition: background 0.2s;
}

.btn-primary:hover {
  background: var(--color-ink-light);
}

@media (max-width: 900px) {
  .hero {
    grid-template-columns: 1fr;
    text-align: center;
    padding-top: 4rem;
  }
  .hero-content p {
    margin: 0 auto 2rem;
  }
  .features {
    grid-template-columns: 1fr;
  }
  .hero-visual {
    justify-content: center;
  }
}