:root {
  --primary: #007BFF;
  --primary-dark: #0056b3;
  --primary-light: #e3f2fd;
  --green: #28a745;
  --green-dark: #1e7e34;
  --gray: #6c757d;
  --text: #333;
  --text-light: #7f8c8d;
  --border: #e0e0e0;
  --bg-card: #ffffff;
  --radius: 12px;
  --shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
}

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

body {
  font-family: 'Arial', 'Microsoft YaHei', sans-serif;
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: flex-start;
  background-color: #f0f2f5;
  color: var(--text);
  line-height: 1.6;
  padding: 20px 0;
  position: relative;
}

/* 顶部渐变背景 */
.bg-gradient {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: 280px;
  background: linear-gradient(135deg, #007BFF 0%, #00d2ff 50%, #28a745 100%);
  opacity: 0.12;
  z-index: 0;
  border-bottom: 1px solid rgba(0, 123, 255, 0.2);
}

.container {
  position: relative;
  z-index: 1;
  max-width: 460px;
  width: 92%;
  padding: 28px 30px;
  background: var(--bg-card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  text-align: center;
}

/* 品牌区 */
.brand { margin-bottom: 22px; }
.logo {
  width: 64px; height: 64px;
  margin: 0 auto 10px;
  font-size: 34px;
  display: flex; align-items: center; justify-content: center;
  background: linear-gradient(135deg, #007BFF, #00c9a7);
  border-radius: 18px;
  box-shadow: 0 6px 18px rgba(0, 123, 255, 0.3);
}
.brand h1 {
  color: #2c3e50;
  font-size: 1.8em;
  font-weight: 700;
  letter-spacing: 1px;
}
.slogan {
  color: var(--text-light);
  font-size: 13px;
  margin-top: 4px;
}

/* 表单 */
.form-group { margin-bottom: 16px; text-align: left; }
.form-group input {
  width: 100%;
  padding: 13px 15px;
  border: 2px solid var(--border);
  border-radius: 8px;
  font-size: 15px;
  transition: border-color 0.3s, box-shadow 0.3s;
  background: #fafbfc;
}
.form-group input:focus {
  border-color: var(--primary);
  outline: none;
  box-shadow: 0 0 0 3px rgba(0, 123, 255, 0.12);
  background: #fff;
}

/* 按钮 */
.btn {
  width: 100%;
  padding: 13px 20px;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  font-size: 16px;
  font-weight: 500;
  transition: all 0.25s;
  margin-top: 6px;
}
.btn-primary {
  background: linear-gradient(135deg, #007BFF, #0056b3);
  color: #fff;
  box-shadow: 0 4px 12px rgba(0, 123, 255, 0.25);
}
.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 16px rgba(0, 123, 255, 0.35);
}
.btn-primary:active { transform: translateY(0); }
.btn-primary:disabled { opacity: 0.6; cursor: not-allowed; }

.btn-guest {
  background: linear-gradient(135deg, #28a745, #20c997);
  color: #fff;
  box-shadow: 0 4px 12px rgba(40, 167, 69, 0.25);
}
.btn-guest:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 16px rgba(40, 167, 69, 0.35);
}
.btn-guest:disabled { opacity: 0.6; cursor: not-allowed; }

/* 分隔线 */
.login-separator {
  display: flex;
  align-items: center;
  margin: 20px 0 12px;
}
.login-separator::before, .login-separator::after {
  content: "";
  flex: 1;
  height: 1px;
  background-color: var(--border);
}
.login-separator span {
  padding: 0 12px;
  color: var(--gray);
  font-size: 13px;
}

/* 链接 */
.related-links {
  margin-top: 16px;
  font-size: 14px;
  color: var(--text-light);
}
.link {
  color: var(--primary);
  text-decoration: none;
  font-weight: 500;
  margin-left: 4px;
}
.link:hover { text-decoration: underline; }

/* 服务介绍 */
.service-intro {
  margin: 22px 0;
  background: #f8f9fa;
  padding: 15px 18px;
  border-radius: 8px;
  text-align: left;
  font-size: 14px;
}
.service-intro strong { color: var(--primary); }
.service-intro .tags {
  margin-top: 8px;
  color: var(--green-dark);
  font-size: 12.5px;
  line-height: 1.7;
}

/* SEO 内容 */
.seo-content {
  margin: 10px 0 16px;
  text-align: left;
  background: #f8f9fa;
  padding: 18px 22px;
  border-radius: 8px;
}
.seo-content h2 {
  color: #2c3e50;
  font-size: 1.15em;
  margin-bottom: 12px;
  font-weight: 600;
}
.seo-content ul { list-style: none; padding-left: 0; }
.seo-content li {
  margin-bottom: 8px;
  padding-left: 26px;
  position: relative;
  font-size: 13.5px;
  color: #444;
}
.seo-content li:before {
  content: "✔";
  color: var(--green);
  position: absolute;
  left: 0;
  top: 0;
  font-size: 1.05em;
}

.footer {
  margin-top: 16px;
  font-size: 12px;
  color: #aaa;
}

/* Toast */
.toast {
  position: fixed;
  top: 24px;
  left: 50%;
  transform: translateX(-50%) translateY(-80px);
  background: rgba(0, 0, 0, 0.82);
  color: #fff;
  padding: 11px 22px;
  border-radius: 8px;
  font-size: 14px;
  z-index: 9999;
  opacity: 0;
  transition: all 0.35s;
  pointer-events: none;
  max-width: 90%;
}
.toast.show { transform: translateX(-50%) translateY(0); opacity: 1; }
.toast.error { background: rgba(220, 53, 69, 0.92); }
.toast.success { background: rgba(40, 167, 69, 0.92); }

/* 顶部导航（登录页也可直达 二维码/合作站点） */
.navbar {
  position: fixed; top: 0; left: 0; right: 0; z-index: 50;
  background: #fff; border-bottom: 1px solid #eee;
  box-shadow: 0 1px 4px rgba(0,0,0,.05);
  padding: 0 16px;
}
.nav-inner {
  max-width: 1100px; margin: 0 auto; height: 56px;
  display: flex; align-items: center; gap: 18px;
}
.nav-brand { display: flex; align-items: center; gap: 8px; text-decoration: none; color: var(--text); font-weight: 700; font-size: 16px; }
.nav-brand-icon { font-size: 20px; }
.nav-links { display: flex; gap: 6px; flex-wrap: wrap; }
.nav-link {
  padding: 7px 12px; border-radius: 8px; text-decoration: none;
  color: #555; font-size: 14px; transition: all .15s;
}
.nav-link:hover { background: #f0f2f5; color: var(--text); }

/* 移动端 */
@media (max-width: 480px) {
  .container { width: 96%; padding: 22px 18px; }
  .brand h1 { font-size: 1.5em; }
  /* 导航换行展示，不隐藏 */
  .navbar { padding: 6px 10px; }
  .nav-inner { flex-wrap: wrap; height: auto; gap: 4px 10px; padding: 4px 0; }
  .nav-brand-name { font-size: 14px; }
  .nav-links { flex: 1 1 100%; order: 3; gap: 2px 6px; }
  .nav-link { padding: 6px 9px; font-size: 13px; white-space: nowrap; }
  body { padding-top: 96px; }
}