/* Reset cơ bản */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: Arial, sans-serif;
}

/* Tổng thể */
body {
  background-color: black;
  color: white;
  text-align: center;
}

/* Container chính */
.container {
  max-width: 900px;
  margin: 0 auto;
  padding: 20px;
}

/* Tiêu đề chính */
.title {
  font-size: 36px;
  font-weight: bold;
  margin-bottom: 30px;
  color: #00ffcc;
  text-shadow: 0 0 10px #00ffcc;
}

/* Phần từng bước */
.step {
  margin-bottom: 40px;
}

.step h2 {
  color: #00ffcc;
  font-size: 24px;
  margin-bottom: 10px;
  text-shadow: 0 0 5px #00ffcc;
}

.step p {
  margin-bottom: 15px;
  line-height: 1.6;
}

.step img {
  width: 90%;
  max-width: 600px;
  border-radius: 10px;
  box-shadow: 0 0 15px #00ffcc;
  margin-top: 10px;
  height: auto;
}

/* Link quay lại */
.back-link {
  color: #9900ff;
  text-decoration: none;
  display: inline-block;
  margin-top: 30px;
  font-weight: bold;
  font-size: 18px;
  transition: 0.3s;
}

.back-link:hover {
  color: #00ffcc;
}

/* Phần chọn thiết bị */
.device-selector {
  margin: 30px 0;
  text-align: center;
}

.device-selector button {
  background-color: transparent;
  color: #00ff00;
  border: 2px solid #00ff00;
  padding: 10px 25px;
  margin: 10px;
  cursor: pointer;
  border-radius: 12px;
  font-size: 16px;
  transition: all 0.3s ease;
}

.device-selector button:hover {
  background-color: #00ff00;
  color: black;
  box-shadow: 0 0 10px #00ff00;
}

/* Hướng dẫn thiết bị (ẩn/hiện) */
.guide-content {
  display: none;
  animation: fadeIn 0.5s ease-in-out;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(15px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Header - nếu dùng */
header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem;
  background-color: #000;
  border-bottom: 2px solid #00ff00;
}

.logo {
  color: #00ff00;
  font-size: 1.5rem;
  font-weight: bold;
}

/* nav {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
} */

nav a {
  color: #fff;
  border: 1px solid #00ff00;
  padding: 0.5rem 1rem;
  border-radius: 5px;
  text-decoration: none;
  transition: 0.3s;
}

nav a:hover {
  background-color: #00ff00;
  color: #000;
}

/* Menu mobile toggle */
.menu-toggle {
  display: flex;
  flex-direction: column;
  cursor: pointer;
  gap: 5px;
}

.menu-toggle span {
  width: 25px;
  height: 3px;
  background-color: #00ff00;
}

/* Hộp liên hệ nổi */
.contact-box {
  position: fixed;
  bottom: 20px;
  right: 20px;
  z-index: 999;
  text-align: right;
}

.contact-toggle {
  background-color: #00ff00;
  color: #000;
  border: none;
  padding: 10px 15px;
  border-radius: 25px;
  cursor: pointer;
  box-shadow: 0 0 10px #00ff00;
}

.contact-options {
  display: none;
  flex-direction: column;
  margin-top: 10px;
  background: #000;
  border: 1px solid #00ff00;
  border-radius: 10px;
  padding: 10px;
}

.contact-options a {
  color: #00ff00;
  text-decoration: none;
  margin: 5px 0;
  display: block;
  transition: 0.3s;
}

.contact-options a:hover {
  color: #000;
  background-color: #00ff00;
  padding-left: 5px;
}

/* Hiển thị khi mở */
.contact-box.active .contact-options {
  display: flex;
}

/* Footer */
footer {
  color: white;
  text-align: center;
  margin-top: 40px;
  padding: 20px 0;
  border-top: 1px solid white;
  font-size: 14px;
}


/* Responsive cho màn nhỏ */
/* @media (max-width: 768px) { */
  nav {
    display: none;
    flex-direction: column;
    background-color: #000;
    padding: 1rem;
    position: absolute;
    top: 60px;
    right: 10px;
    border: 1px solid #00ff00;
  }

  nav.active {
    display: flex;
  }

  /* .menu-toggle {
    display: flex;
  } */

  /* .step img {
    max-width: 100%;
  } */

  .title {
    font-size: 28px;
  }
/* } */