/* Reset */
* {
  margin: 0; 
  padding: 0; 
  box-sizing: border-box; 
  font-family: 'Mulish', sans-serif;
}

body {
  background: linear-gradient(135deg, #0f0f0f, #1c1c1c);
  color: #fff;
  padding: 50px 20px;
}

h1, h2 {
  text-align: center;
  margin-bottom: 10px;
}

h1 {
  font-size: 2.4rem;
  font-weight: 700;
  background: linear-gradient(90deg, #00ffe0, #ff00cc);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

h2 {
  font-size: 1rem;
  color: #aaa;
  letter-spacing: 2px;
}

p.tagline {
  text-align: center;
  margin: 20px 0 40px;
  font-size: 1.2rem;
  color: #ccc;
}

.plans {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 30px;
  max-width: 1100px;
  margin: 0 auto;
}

.card {
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.15);
  border-radius: 20px;
  padding: 30px 25px;
  backdrop-filter: blur(10px);
  box-shadow: 0 8px 25px rgba(0,0,0,0.4);
  transition: transform 0.3s, box-shadow 0.3s;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.card:hover {
  transform: translateY(-10px);
  box-shadow: 0 12px 35px rgba(0,0,0,0.6);
}

.card h3 {
  font-size: 1.5rem;
  margin-bottom: 15px;
  background: linear-gradient(90deg, #00ffe0, #ff00cc);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

ul {
  list-style: none;
  margin-bottom: 20px;
}

ul li {
  margin: 10px 0;
  font-size: 0.95rem;
  color: #ddd;
  position: relative;
  padding-left: 20px;
}

ul li::before {
  content: "✔";
  position: absolute;
  left: 0;
  color: #00ffe0;
}

.price {
  font-size: 1.2rem;
  font-weight: 600;
  margin-top: auto;
  color: #fff;
  background: rgba(255,255,255,0.08);
  border-radius: 12px;
  padding: 12px 15px;
  text-align: center;
  border: 1px solid rgba(255,255,255,0.2);
}

/* Zalo Button */
.zalo-button {
  position: fixed;
  bottom: 30px;
  right: 30px;
  background: linear-gradient(135deg, #0084ff, #00a3ff);
  color: white;
  padding: 15px 20px;
  border-radius: 50px;
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 14px;
  font-weight: 600;
  box-shadow: 0 8px 25px rgba(0, 132, 255, 0.4);
  transition: all 0.3s ease;
  z-index: 1000;
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.zalo-button:hover {
  transform: translateY(-3px) scale(1.05);
  box-shadow: 0 12px 35px rgba(0, 132, 255, 0.6);
  background: linear-gradient(135deg, #0074e6, #0093e6);
}

.zalo-button svg {
  flex-shrink: 0;
}

.zalo-button span {
  white-space: nowrap;
}

/* Responsive for Zalo Button */
@media (max-width: 768px) {
  .zalo-button {
    bottom: 20px;
    right: 20px;
    padding: 12px 16px;
    font-size: 13px;
  }
  
  .zalo-button svg {
    width: 20px;
    height: 20px;
  }
}

/* Responsive */
@media (max-width: 768px) {
  h1 {
    font-size: 1.8rem;
  }
  
  .plans {
    gap: 20px;
  }
  
  .card {
    padding: 25px 20px;
  }
}