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

html, body {
  height: 100%;
  font-family: 'Segoe UI', Roboto, system-ui, sans-serif;
  overflow-x: hidden;
}

/* 背景蓝色渐变 + 初始载入渐变动画 */
body {
  min-height: 100vh;
  background: linear-gradient(145deg, #a0c4ff 0%, #4a6fa5 100%);
  animation: fadeIn 1.2s ease-out;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 16px;
}

@keyframes fadeIn {
  0% { opacity: 0; backdrop-filter: blur(10px); }
  100% { opacity: 1; backdrop-filter: blur(0); }
}

/* 主卡片 - 半透明磨砂效果 */
.container {
  width: 100%;
  max-width: 600px;
  background: rgba(255, 255, 255, 0.2);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-radius: 48px 48px 32px 32px;
  padding: 32px 24px 40px 24px;
  box-shadow: 0 20px 40px rgba(0, 30, 60, 0.3);
  border: 1px solid rgba(255, 255, 255, 0.4);
  position: relative;
  z-index: 10;
  margin: 20px 0;
}

/* 标题与说明 */
h1 {
  font-size: 2.4rem;
  font-weight: 600;
  color: white;
  text-shadow: 0 4px 12px rgba(0, 40, 80, 0.4);
  letter-spacing: 1px;
  margin-bottom: 8px;
  text-align: center;
}

.subtitle {
  text-align: center;
  color: rgba(255, 255, 255, 0.9);
  margin-bottom: 32px;
  font-size: 1rem;
  font-weight: 300;
  backdrop-filter: blur(5px);
}

/* 输入框 + 按钮 */
.input-group {
  display: flex;
  flex-direction: column;
  gap: 16px;
  margin-bottom: 28px;
}

@media (min-width: 500px) {
  .input-group {
    flex-direction: row;
  }
}

.input-group input {
  flex: 1;
  padding: 16px 24px;
  border: none;
  border-radius: 60px;
  background: rgba(255, 255, 255, 0.9);
  box-shadow: inset 0 4px 8px rgba(0, 0, 0, 0.05), 0 2px 4px rgba(0,20,40,0.2);
  font-size: 1.1rem;
  outline: none;
  transition: 0.2s;
  color: #1e3b5c;
}

.input-group input:focus {
  background: white;
  box-shadow: 0 0 0 4px rgba(255, 255, 255, 0.5);
}

.input-group button {
  padding: 16px 32px;
  border: none;
  border-radius: 60px;
  background: #1e4b7c;
  color: white;
  font-weight: 600;
  font-size: 1.1rem;
  cursor: pointer;
  box-shadow: 0 8px 20px rgba(0, 30, 70, 0.4);
  transition: all 0.2s;
  border: 1px solid rgba(255,255,255,0.3);
  letter-spacing: 0.5px;
  white-space: nowrap;
}

.input-group button:hover {
  background: #2a5f9c;
  transform: scale(1.02);
  box-shadow: 0 12px 28px rgba(0, 50, 100, 0.5);
}

/* 结果显示 */
.result-box {
  background: rgba(255, 255, 255, 0.25);
  border-radius: 40px;
  padding: 16px 24px;
  margin: 24px 0 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  border: 1px solid rgba(255,255,255,0.3);
  backdrop-filter: blur(8px);
}

.result-box .short-url {
  color: white;
  font-weight: 500;
  word-break: break-all;
  font-size: 1.2rem;
  text-shadow: 0 2px 4px rgba(0,0,0,0.2);
}

.result-box .copy-btn {
  background: white;
  border: none;
  padding: 10px 24px;
  border-radius: 40px;
  color: #1e3b5c;
  font-weight: 600;
  cursor: pointer;
  transition: 0.2s;
  box-shadow: 0 4px 12px rgba(0, 30, 60, 0.3);
}

.result-box .copy-btn:hover {
  background: #e6f0ff;
  transform: scale(1.02);
}

/* 推荐按钮区域 */
.recommend-section {
  margin-top: 30px;
  display: flex;
  justify-content: center;
  gap: 20px;
  flex-wrap: wrap;
}

.recommend-btn {
  background: rgba(255, 255, 255, 0.3);
  backdrop-filter: blur(12px);
  border: 1px solid rgba(255,255,255,0.5);
  color: white;
  padding: 14px 30px;
  border-radius: 50px;
  font-size: 1.1rem;
  font-weight: 500;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  box-shadow: 0 10px 20px rgba(0, 30, 70, 0.3);
  transition: 0.2s;
}

.recommend-btn:hover {
  background: rgba(255, 255, 255, 0.5);
  transform: translateY(-3px);
  box-shadow: 0 18px 30px rgba(0, 40, 80, 0.4);
  color: #0a2a44;
}

/* 管理员入口小链接 */
.admin-link {
  margin-top: 20px;
  text-align: center;
}

.admin-link a {
  color: rgba(255,255,255,0.7);
  text-decoration: none;
  font-size: 0.9rem;
  border-bottom: 1px dotted rgba(255,255,255,0.4);
  padding-bottom: 2px;
  transition: 0.2s;
}

.admin-link a:hover {
  color: white;
  border-bottom-color: white;
}