/* ========================================
   全局样式和重置
   ======================================== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  /* 颜色系统 */
  --primary-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --secondary-gradient: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
  --dark-bg: #0f0e17;
  --card-bg: rgba(255, 255, 255, 0.05);
  --card-border: rgba(255, 255, 255, 0.1);
  --text-primary: #fffffe;
  --text-secondary: #a7a9be;
  --accent: #667eea;
  --success: #06d6a0;
  --danger: #ef476f;
  --warning: #ffd60a;
  
  /* 间距 */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2rem;
  --spacing-xl: 3rem;
  
  /* 阴影 */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.2);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.3);
  
  /* 圆角 */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", "微软雅黑", sans-serif;
  background: var(--dark-bg);
  background-image: 
    radial-gradient(at 0% 0%, rgba(102, 126, 234, 0.2) 0px, transparent 50%),
    radial-gradient(at 100% 100%, rgba(118, 75, 162, 0.2) 0px, transparent 50%);
  background-attachment: fixed;
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  overflow-x: hidden;
}

.container {
  width: 100%;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-md);
}

/* ========================================
   玻璃态卡片效果
   ======================================== */
.glass-card {
  background: var(--card-bg);
  backdrop-filter: blur(10px);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
}

/* ========================================
   按钮样式
   ======================================== */
.btn {
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: var(--radius-sm);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  text-transform: none;
  font-family: inherit;
}

.btn-primary {
  background: var(--primary-gradient);
  color: white;
  box-shadow: var(--shadow-sm);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.btn-primary:active {
  transform: translateY(0);
}

.btn-secondary {
  background: var(--card-bg);
  color: var(--text-primary);
  border: 1px solid var(--card-border);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.1);
}

.btn-small {
  padding: 0.5rem 1rem;
  font-size: 0.875rem;
}

.btn-admin {
  background: var(--warning);
  color: var(--dark-bg);
  width: 100%;
}

.btn-admin:hover {
  background: #ffed4e;
}

.btn-send {
  background: var(--accent);
  color: white;
  padding: 0.75rem 2rem;
}

.btn-send:hover {
  background: #7c93f5;
}

.btn-danger {
  background: var(--danger);
  color: white;
}

.btn-danger:hover {
  background: #ff6b8a;
}

.btn-success {
  background: var(--success);
  color: white;
}

.btn-success:hover {
  background: #08ffbe;
}

/* ========================================
   登录/注册界面
   ======================================== */
.auth-card {
  background: var(--card-bg);
  backdrop-filter: blur(20px);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-xl);
  padding: var(--spacing-xl);
  max-width: 450px;
  width: 100%;
  box-shadow: var(--shadow-lg);
  animation: fadeIn 0.5s ease;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.app-title {
  font-size: 2rem;
  text-align: center;
  margin-bottom: var(--spacing-xs);
  background: var(--primary-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.app-subtitle {
  text-align: center;
  color: var(--text-secondary);
  margin-bottom: var(--spacing-lg);
  font-size: 0.9rem;
}

.auth-form h2 {
  margin-bottom: var(--spacing-md);
  color: var(--text-primary);
}

.form-group {
  margin-bottom: var(--spacing-md);
}

.form-group label {
  display: block;
  margin-bottom: var(--spacing-xs);
  color: var(--text-secondary);
  font-size: 0.9rem;
}

.form-group input {
  width: 100%;
  padding: 0.75rem;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-size: 1rem;
  transition: all 0.3s ease;
  font-family: inherit;
}

.form-group input:focus {
  outline: none;
  border-color: var(--accent);
  background: rgba(255, 255, 255, 0.08);
}

.form-group input::placeholder {
  color: var(--text-secondary);
}

.form-switch {
  text-align: center;
  margin-top: var(--spacing-md);
  color: var(--text-secondary);
  font-size: 0.9rem;
}

.form-switch a {
  color: var(--accent);
  text-decoration: none;
  font-weight: 600;
}

.form-switch a:hover {
  text-decoration: underline;
}

.info-text {
  background: rgba(255, 214, 10, 0.1);
  border-left: 3px solid var(--warning);
  padding: var(--spacing-sm);
  margin-bottom: var(--spacing-md);
  border-radius: var(--radius-sm);
  color: var(--warning);
  font-size: 0.9rem;
}

/* ========================================
   聊天界面
   ======================================== */
.chat-wrapper {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: var(--spacing-md);
  width: 100%;
  max-width: 1400px;
  height: 85vh;
}

/* 侧边栏 */
.sidebar {
  background: var(--card-bg);
  backdrop-filter: blur(20px);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  padding: var(--spacing-md);
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
}

.sidebar-header {
  border-bottom: 1px solid var(--card-border);
  padding-bottom: var(--spacing-md);
}

.sidebar-header h2 {
  margin-bottom: var(--spacing-sm);
  font-size: 1.25rem;
}

.user-info {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--spacing-sm);
}

.user-info span {
  color: var(--accent);
  font-weight: 600;
  font-size: 0.9rem;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.online-users {
  flex: 1;
  overflow-y: auto;
}

.online-users h3 {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-bottom: var(--spacing-sm);
  text-transform: uppercase;
  letter-spacing: 1px;
}

.online-users ul {
  list-style: none;
}

.online-users li {
  padding: var(--spacing-xs);
  margin-bottom: var(--spacing-xs);
  background: rgba(255, 255, 255, 0.03);
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
}

.online-users li::before {
  content: "●";
  color: var(--success);
  font-size: 0.5rem;
}

/* 聊天主区域 */
.chat-main {
  background: var(--card-bg);
  backdrop-filter: blur(20px);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.chat-header {
  padding: var(--spacing-md);
  border-bottom: 1px solid var(--card-border);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.chat-header h3 {
  font-size: 1.25rem;
}

.stats {
  color: var(--text-secondary);
  font-size: 0.9rem;
}

.messages-container {
  flex: 1;
  overflow-y: auto;
  padding: var(--spacing-md);
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

.message {
  background: rgba(255, 255, 255, 0.05);
  padding: var(--spacing-sm);
  border-radius: var(--radius-md);
  border-left: 3px solid var(--accent);
  animation: slideIn 0.3s ease;
}

@keyframes slideIn {
  from {
    opacity: 0;
    transform: translateX(-20px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

.message-header {
  display: flex;
  justify-content: space-between;
  margin-bottom: var(--spacing-xs);
  font-size: 0.85rem;
}

.message-author {
  font-weight: 600;
  color: var(--accent);
}

.message-time {
  color: var(--text-secondary);
}

.message-content {
  color: var(--text-primary);
  word-wrap: break-word;
}

.message-input-container {
  padding: var(--spacing-md);
  border-top: 1px solid var(--card-border);
  display: flex;
  gap: var(--spacing-sm);
}

.message-input-container input {
  flex: 1;
  padding: 0.75rem;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-size: 1rem;
  font-family: inherit;
}

.message-input-container input:focus {
  outline: none;
  border-color: var(--accent);
  background: rgba(255, 255, 255, 0.08);
}

/* ========================================
   管理员控制台
   ======================================== */
.admin-wrapper {
  width: 100%;
  max-width: 1200px;
}

.admin-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--spacing-lg);
}

.admin-header h1 {
  font-size: 2rem;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-xl);
}

.stat-card {
  background: var(--card-bg);
  backdrop-filter: blur(20px);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  padding: var(--spacing-md);
  text-align: center;
}

.stat-card h3 {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-bottom: var(--spacing-xs);
  text-transform: uppercase;
  letter-spacing: 1px;
}

.stat-number {
  font-size: 2.5rem;
  font-weight: 700;
  background: var(--primary-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.admin-section {
  background: var(--card-bg);
  backdrop-filter: blur(20px);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  margin-bottom: var(--spacing-lg);
}

.admin-section h2 {
  margin-bottom: var(--spacing-md);
  font-size: 1.5rem;
}

.pending-request,
.user-item {
  background: rgba(255, 255, 255, 0.03);
  padding: var(--spacing-md);
  border-radius: var(--radius-md);
  margin-bottom: var(--spacing-sm);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.pending-request-info,
.user-info-detail {
  flex: 1;
}

.pending-request-info h4,
.user-info-detail h4 {
  margin-bottom: var(--spacing-xs);
  color: var(--text-primary);
}

.pending-request-info p,
.user-info-detail p {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.pending-actions,
.user-actions {
  display: flex;
  gap: var(--spacing-sm);
}

.empty-text {
  text-align: center;
  color: var(--text-secondary);
  padding: var(--spacing-xl);
  font-style: italic;
}

/* ========================================
   响应式设计
   ======================================== */
@media (max-width: 768px) {
  .chat-wrapper {
    grid-template-columns: 1fr;
    height: auto;
    min-height: 85vh;
  }
  
  .sidebar {
    order: 2;
    max-height: 300px;
  }
  
  .chat-main {
    order: 1;
    min-height: 500px;
  }
  
  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .admin-header {
    flex-direction: column;
    gap: var(--spacing-md);
    align-items: stretch;
  }
}

/* ========================================
   滚动条样式
   ======================================== */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: rgba(255, 255, 255, 0.05);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb {
  background: rgba(255, 255, 255, 0.2);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: rgba(255, 255, 255, 0.3);
}