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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 20px;
}

/* ===== 登录框 ===== */
.login-box {
  background: #fff;
  padding: 40px 36px;
  border-radius: 20px;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.2);
  width: 400px;
  max-width: 100%;
  text-align: center;
}

.logo {
  font-size: 48px;
  margin-bottom: 8px;
}

.login-box h1 {
  font-size: 24px;
  color: #1a1a2e;
  margin-bottom: 4px;
}

.subtitle {
  color: #999;
  font-size: 14px;
  margin-bottom: 28px;
}

/* ===== Tab 切换 ===== */
.tabs {
  display: flex;
  margin-bottom: 24px;
  background: #f5f5f8;
  border-radius: 10px;
  padding: 4px;
}

.tab {
  flex: 1;
  padding: 10px;
  cursor: pointer;
  border: none;
  background: transparent;
  font-size: 14px;
  font-weight: 500;
  color: #999;
  border-radius: 8px;
  transition: all 0.3s ease;
}

.tab.active {
  background: #fff;
  color: #667eea;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

/* ===== Tab 内容 ===== */
.tab-content {
  display: none;
}

.tab-content.active {
  display: block;
}

/* ===== 表单 ===== */
.form-group {
  margin-bottom: 16px;
  text-align: left;
}

.form-group label {
  display: block;
  margin-bottom: 6px;
  font-size: 13px;
  font-weight: 500;
  color: #555;
}

.form-group input {
  width: 100%;
  padding: 12px 16px;
  border: 1.5px solid #e0e0e5;
  border-radius: 10px;
  font-size: 15px;
  outline: none;
  transition: all 0.3s ease;
  background: #fafafa;
}

.form-group input:focus {
  border-color: #667eea;
  background: #fff;
  box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.15);
}

.form-group input::placeholder {
  color: #bbb;
}

/* 验证码行 */
.code-row {
  display: flex;
  gap: 8px;
}

.code-row input {
  flex: 1;
}

.code-row button {
  padding: 12px 18px;
  border: none;
  background: linear-gradient(135deg, #667eea, #764ba2);
  color: #fff;
  border-radius: 10px;
  cursor: pointer;
  font-size: 13px;
  font-weight: 500;
  white-space: nowrap;
  transition: all 0.3s ease;
}

.code-row button:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}

.code-row button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
}

/* ===== 主按钮 ===== */
.btn-primary {
  width: 100%;
  padding: 14px;
  background: linear-gradient(135deg, #667eea, #764ba2);
  color: #fff;
  border: none;
  border-radius: 10px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  margin-top: 4px;
  transition: all 0.3s ease;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(102, 126, 234, 0.4);
}

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

.btn-primary:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
}

/* ===== 提示信息 ===== */
.alert {
  padding: 10px 14px;
  border-radius: 8px;
  font-size: 14px;
  margin-bottom: 12px;
  display: none;
  text-align: left;
}

.alert.error {
  display: none;
  background: #fff0f0;
  color: #e74c3c;
  border: 1px solid #ffd0d0;
}

.alert.success {
  display: none;
  background: #f0fff4;
  color: #07c160;
  border: 1px solid #c6f6d5;
}

/* ===== 分割线 ===== */
.divider {
  margin: 24px 0;
  display: flex;
  align-items: center;
  color: #bbb;
  font-size: 13px;
}

.divider::before,
.divider::after {
  content: "";
  flex: 1;
  height: 1px;
  background: #ebebeb;
}

.divider span {
  padding: 0 16px;
}

/* ===== 第三方登录 ===== */
.social-login {
  display: flex;
  gap: 20px;
  justify-content: center;
}

.social-btn {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all 0.3s ease;
  text-decoration: none;
  border: none;
}

.social-btn:hover {
  transform: scale(1.12);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.2);
}

.social-btn.qq {
  background: #12b7f5;
  color: #fff;
}

.social-btn.wechat {
  background: #07c160;
  color: #fff;
}

/* ===== 底部链接 ===== */
.footer-link {
  margin-top: 24px;
  font-size: 13px;
  color: #999;
}

.footer-link a {
  color: #667eea;
  text-decoration: none;
  font-weight: 500;
}

.footer-link a:hover {
  text-decoration: underline;
}

/* ===== 首页样式 ===== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  padding: 16px 32px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  box-shadow: 0 2px 20px rgba(0, 0, 0, 0.08);
  z-index: 100;
}

.navbar .brand {
  font-size: 20px;
  font-weight: 700;
  color: #1a1a2e;
}

.navbar .user-area {
  display: flex;
  align-items: center;
  gap: 12px;
}

.navbar .user-area a {
  text-decoration: none;
  color: #667eea;
  font-weight: 500;
}

.btn-logout {
  padding: 8px 20px;
  background: #f5f5f8;
  border: 1px solid #e0e0e5;
  border-radius: 8px;
  cursor: pointer;
  font-size: 14px;
  color: #666;
  transition: all 0.2s;
}

.btn-logout:hover {
  background: #ff4757;
  color: #fff;
  border-color: #ff4757;
}

.hero {
  text-align: center;
  padding-top: 140px;
  min-height: 100vh;
}

.hero h1 {
  font-size: 48px;
  background: linear-gradient(135deg, #667eea, #764ba2);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 16px;
}

.hero p {
  font-size: 18px;
  color: #777;
  max-width: 600px;
  margin: 0 auto 40px;
}

.hero .card {
  background: #fff;
  border-radius: 16px;
  padding: 40px;
  max-width: 500px;
  margin: 0 auto;
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
}

.hero .card h2 {
  color: #1a1a2e;
  margin-bottom: 8px;
}

.hero .card p {
  color: #999;
  font-size: 14px;
}