/* Bootstrap 5.3.2 核心样式备用文件 */
/* 如果CDN失败，这个文件提供基本的样式支持 */

:root {
  --bs-blue: #0d6efd;
  --bs-indigo: #6610f2;
  --bs-purple: #6f42c1;
  --bs-pink: #d63384;
  --bs-red: #dc3545;
  --bs-orange: #fd7e14;
  --bs-yellow: #ffc107;
  --bs-green: #198754;
  --bs-teal: #20c997;
  --bs-cyan: #0dcaf0;
  --bs-white: #fff;
  --bs-gray: #6c757d;
  --bs-gray-dark: #343a40;
  --bs-primary: #0d6efd;
  --bs-secondary: #6c757d;
  --bs-success: #198754;
  --bs-info: #0dcaf0;
  --bs-warning: #ffc107;
  --bs-danger: #dc3545;
  --bs-light: #f8f9fa;
  --bs-dark: #212529;
}

/* 基础样式 */
* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 1rem;
  font-weight: 400;
  line-height: 1.5;
  color: #212529;
  background-color: #fff;
}

/* 容器 */
.container {
  width: 100%;
  padding-right: 15px;
  padding-left: 15px;
  margin-right: auto;
  margin-left: auto;
}

@media (min-width: 576px) {
  .container { max-width: 540px; }
}

@media (min-width: 768px) {
  .container { max-width: 720px; }
}

@media (min-width: 992px) {
  .container { max-width: 960px; }
}

@media (min-width: 1200px) {
  .container { max-width: 1140px; }
}

/* 网格系统 */
.row {
  display: flex;
  flex-wrap: wrap;
  margin-right: -15px;
  margin-left: -15px;
}

.col-md-6 {
  flex: 0 0 50%;
  max-width: 50%;
  padding-right: 15px;
  padding-left: 15px;
}

@media (max-width: 767.98px) {
  .col-md-6 {
    flex: 0 0 100%;
    max-width: 100%;
  }
}

/* 卡片 */
.card {
  position: relative;
  display: flex;
  flex-direction: column;
  min-width: 0;
  word-wrap: break-word;
  background-color: #fff;
  background-clip: border-box;
  border: 1px solid rgba(0,0,0,.125);
  border-radius: 0.375rem;
}

.card-header {
  padding: 0.5rem 1rem;
  margin-bottom: 0;
  background-color: rgba(0,0,0,.03);
  border-bottom: 1px solid rgba(0,0,0,.125);
}

.card-body {
  flex: 1 1 auto;
  padding: 1rem;
}

/* 按钮 */
.btn {
  display: inline-block;
  font-weight: 400;
  line-height: 1.5;
  color: #212529;
  text-align: center;
  text-decoration: none;
  vertical-align: middle;
  cursor: pointer;
  user-select: none;
  background-color: transparent;
  border: 1px solid transparent;
  padding: 0.375rem 0.75rem;
  font-size: 1rem;
  border-radius: 0.375rem;
  transition: color .15s ease-in-out,background-color .15s ease-in-out,border-color .15s ease-in-out,box-shadow .15s ease-in-out;
}

.btn-primary {
  color: #fff;
  background-color: #0d6efd;
  border-color: #0d6efd;
}

.btn-primary:hover {
  color: #fff;
  background-color: #0b5ed7;
  border-color: #0a58ca;
}

.btn-lg {
  padding: 0.5rem 1rem;
  font-size: 1.25rem;
  border-radius: 0.5rem;
}

/* 表单 */
.form-label {
  margin-bottom: 0.5rem;
  font-weight: 500;
}

.form-control {
  display: block;
  width: 100%;
  padding: 0.375rem 0.75rem;
  font-size: 1rem;
  font-weight: 400;
  line-height: 1.5;
  color: #212529;
  background-color: #fff;
  background-image: none;
  border: 1px solid #ced4da;
  border-radius: 0.375rem;
  transition: border-color .15s ease-in-out,box-shadow .15s ease-in-out;
}

.form-select {
  display: block;
  width: 100%;
  padding: 0.375rem 2.25rem 0.375rem 0.75rem;
  font-size: 1rem;
  font-weight: 400;
  line-height: 1.5;
  color: #212529;
  background-color: #fff;
  background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16'%3e%3cpath fill='none' stroke='%23343a40' stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='m1 6 7 7 7-7'/%3e%3c/svg%3e");
  background-repeat: no-repeat;
  background-position: right 0.75rem center;
  background-size: 16px 12px;
  border: 1px solid #ced4da;
  border-radius: 0.375rem;
  transition: border-color .15s ease-in-out,box-shadow .15s ease-in-out;
}

/* 导航栏 */
.navbar {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  padding-top: 0.5rem;
  padding-bottom: 0.5rem;
}

.navbar-brand {
  padding-top: 0.3125rem;
  padding-bottom: 0.3125rem;
  margin-right: 1rem;
  font-size: 1.25rem;
  color: #000;
  text-decoration: none;
}

.navbar-dark {
  background-color: #212529;
}

.navbar-dark .navbar-brand {
  color: #fff;
}

/* 工具类 */
.d-none { display: none !important; }
.d-block { display: block !important; }
.d-flex { display: flex !important; }
.d-grid { display: grid !important; }

.text-center { text-align: center !important; }
.text-primary { color: #0d6efd !important; }
.text-success { color: #198754 !important; }
.text-danger { color: #dc3545 !important; }
.text-muted { color: #6c757d !important; }

.bg-primary { background-color: #0d6efd !important; }
.bg-success { background-color: #198754 !important; }
.bg-danger { background-color: #dc3545 !important; }
.bg-light { background-color: #f8f9fa !important; }
.bg-dark { background-color: #212529 !important; }

.text-white { color: #fff !important; }

.mb-0 { margin-bottom: 0 !important; }
.mb-2 { margin-bottom: 0.5rem !important; }
.mb-3 { margin-bottom: 1rem !important; }
.mb-4 { margin-bottom: 1.5rem !important; }
.mb-5 { margin-bottom: 3rem !important; }

.mt-2 { margin-top: 0.5rem !important; }
.mt-3 { margin-top: 1rem !important; }
.mt-4 { margin-top: 1.5rem !important; }
.mt-5 { margin-top: 3rem !important; }

.p-3 { padding: 1rem !important; }
.py-3 { padding-top: 1rem !important; padding-bottom: 1rem !important; }

/* 响应式 */
@media (max-width: 575.98px) {
  .container {
    padding-right: 10px;
    padding-left: 10px;
  }
}