* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: sans-serif;
  height: 100vh;
}

.split {
  display: flex;
  width: 100%;
  height: 100%;
}

.panel {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 40px;
  transition: flex 0.5s ease;
}

.panel.left {
  background-color: #1a1b2e;
  color: #e8eef4;
}

.panel.right {
  background-color: white;
  color: #2d2a26;
}

.left:hover {
  flex: 2;
}

/* The :has() pseudo-class is a parent selector that lets you select an element based on what it contains. */

/* Why use it? Before :has(), CSS could only select downward (parent → child). You couldn't style something based on a child's state. Now you can. */

.split:has(.left:hover) .right {
  flex: 0.8;
}

.right:hover {
  flex: 2;
}

.split:has(.right:hover) .left {
  flex: 0.8;
}

.content {
  max-width: 320px;
  text-align: center;
}

.content h2 {
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: 12px;
  letter-spacing: -0.02em;
}

.content p {
  font-size: 1.05rem;
  line-height: 1.6;
  opacity: 0.9;
  margin-bottom: 24px;
}

.btn {
  display: inline-block;
  padding: 12px 28px;
  font-size: 0.95rem;
  font-weight: 600;
  text-decoration: none;
  border-radius: 8px;
  transition: all 0.2s;
}

.panel.left .btn {
  background: #fff;
  color: #1a1b2e;
  border: 2px solid rgba(255, 255, 255, 0.3);
}

.panel.right .btn {
  background: #1a1b2e;
  color: #f8f6f3;
  border: 2px solid #1a1b2e;
}

@media (max-width: 768px) {
  .split {
    flex-direction: column;
  }

  .panel {
    flex: 1;
    min-height: 50vh;
  }

  .left:hover,
  .right:hover,
  .split:has(.left:hover) .right,
  .split:has(.right:hover) .left {
    flex: 1;
  }

  .content h2 {
    font-size: 2rem;
  }
}