:root {
  --font-size-base: 16px; 
  --primary-color: black;
  --hover-color: #0278ff;
  --icon-size: 1.875rem; 
  --icon-size-small: 1.5rem; 
}

body {
  font-family: 'LXGWWenKai', sans-serif; 
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  justify-content: flex-start;
  align-items: center;
  min-height: 100vh;
  background-image: url('/image/placeholder.png');
  background-size: cover;
  background-position: center;
  color: black;
  transition: all 0.3s ease-in-out; 
}

/* 标题样式 */
.title-container {
  display: flex;
  justify-content: center;
  align-items: center;
  flex-direction: column;
  margin-top: 10%;
}

.title-link {
  font-size: 2.25rem;
  font-weight: bold;
  padding: 0;
  color: var(--primary-color);
  text-decoration: none;
  position: relative;
  opacity: 1;
  text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.5);
  transition: color 0.3s ease, transform 0.3s ease;
  animation: fadeIn 0.5s ease-out; 
}

.title-link::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: -5px;
  width: 100%;
  height: 2px;
}

.title-link:hover {
  transform: scale(1.2);
}

/* 社交图标容器 */
.social-container {
  display: flex;
  justify-content: center;
  align-items: center;
  flex-direction: column;
  flex-grow: 1;
  width: 100%;
}

/* 社交图标列表 */
.social-links {
  list-style-type: none;
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 0;
  padding-left: 0;
}

/* 图标逐出效果 */
.social-links li {
  text-decoration: none;
  display: inline-block;
  padding: 10px;
  margin: 5px;
  list-style-type: none;
  transform: scale(1); 
  opacity: 0; 
  animation: fadeIn 0.5s ease-out forwards; 
  transition: transform 0.3s ease, opacity 0.3s ease, color 0.3s ease;
}

.social-links li a i {
  font-size: var(--icon-size);
  color: var(--primary-color);
  transition: color 0.3s ease, transform 0.3s ease; 
}

.social-links li:hover a i {
  transform: scale(1.5); 
  color: var(--hover-color); 
}

/* 页脚 */
footer {
  text-align: center;
  font-size: 1rem;
  padding: 10px 0;
  width: 100%;
}

footer p {
  margin: 0;
}

.footer-link {
  color: black;
  text-decoration: none;
  transition: color 0.3s ease;
}

.footer-link:hover {
  color: var(--hover-color);
}

.separator {
  margin: 0 8px; 
  font-weight: bold; 
}

/* 动画：元素从透明到可见，并且从小到大 */
@keyframes fadeIn {
  0% {
    opacity: 0;
    transform: scale(0.5);
  }
  100% {
    opacity: 1;
    transform: scale(1);
  }
}

/* 响应式设计 */
@media (max-width: 768px) {
  .title-link {
    font-size: 1.5rem;
    padding: 10px 15px; 
    transition: font-size 0.3s ease, padding 0.3s ease; 
  }

  .social-links li {
    transform: scale(1); 
    opacity: 1; 
  }

  .social-links li a i {
    font-size: var(--icon-size-small); 
  }
}