/* 实用工具类 */

/* 间距 */
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }
.mt-5 { margin-top: 3rem; }

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

.mr-1 { margin-right: 0.5rem; }
.mr-2 { margin-right: 1rem; }
.mr-3 { margin-right: 1.5rem; }
.mr-4 { margin-right: 2rem; }
.mr-5 { margin-right: 3rem; }

.ml-1 { margin-left: 0.5rem; }
.ml-2 { margin-left: 1rem; }
.ml-3 { margin-left: 1.5rem; }
.ml-4 { margin-left: 2rem; }
.ml-5 { margin-left: 3rem; }

.pt-1 { padding-top: 0.5rem; }
.pt-2 { padding-top: 1rem; }
.pt-3 { padding-top: 1.5rem; }
.pt-4 { padding-top: 2rem; }
.pt-5 { padding-top: 3rem; }

.pb-1 { padding-bottom: 0.5rem; }
.pb-2 { padding-bottom: 1rem; }
.pb-3 { padding-bottom: 1.5rem; }
.pb-4 { padding-bottom: 2rem; }
.pb-5 { padding-bottom: 3rem; }

.pr-1 { padding-right: 0.5rem; }
.pr-2 { padding-right: 1rem; }
.pr-3 { padding-right: 1.5rem; }
.pr-4 { padding-right: 2rem; }
.pr-5 { padding-right: 3rem; }

.pl-1 { padding-left: 0.5rem; }
.pl-2 { padding-left: 1rem; }
.pl-3 { padding-left: 1.5rem; }
.pl-4 { padding-left: 2rem; }
.pl-5 { padding-left: 3rem; }

/* 文本对齐 */
.text-left { text-align: left; }
.text-center { text-align: center; }
.text-right { text-align: right; }
.text-justify { text-align: justify; }

/* 显示属性 */
.d-none { display: none; }
.d-inline { display: inline; }
.d-inline-block { display: inline-block; }
.d-block { display: block; }
.d-flex { display: flex; }
.d-inline-flex { display: inline-flex; }

/* Flexbox */
.flex-row { flex-direction: row; }
.flex-column { flex-direction: column; }
.flex-wrap { flex-wrap: wrap; }
.flex-nowrap { flex-wrap: nowrap; }
.justify-content-start { justify-content: flex-start; }
.justify-content-end { justify-content: flex-end; }
.justify-content-center { justify-content: center; }
.justify-content-between { justify-content: space-between; }
.justify-content-around { justify-content: space-around; }
.align-items-start { align-items: flex-start; }
.align-items-end { align-items: flex-end; }
.align-items-center { align-items: center; }
.align-items-baseline { align-items: baseline; }
.align-items-stretch { align-items: stretch; }

/* 宽度和高度 */
.w-25 { width: 25%; }
.w-50 { width: 50%; }
.w-75 { width: 75%; }
.w-100 { width: 100%; }
.h-25 { height: 25%; }
.h-50 { height: 50%; }
.h-75 { height: 75%; }
.h-100 { height: 100%; }

/* 响应式实用工具 */
@media (max-width: 768px) {
  .d-md-none { display: none; }
  .d-md-block { display: block; }
  .d-md-flex { display: flex; }
  .text-md-center { text-align: center; }
}

@media (max-width: 480px) {
  .d-sm-none { display: none; }
  .d-sm-block { display: block; }
  .d-sm-flex { display: flex; }
  .text-sm-center { text-align: center; }
}

/* 颜色类 */
.text-primary { color: #3498db; }
.text-secondary { color: #95a5a6; }
.text-success { color: #2ecc71; }
.text-warning { color: #f39c12; }
.text-danger { color: #e74c3c; }
.text-info { color: #3498db; }
.text-light { color: #f8f9fa; }
.text-dark { color: #2c3e50; }

.bg-primary { background-color: #3498db; }
.bg-secondary { background-color: #95a5a6; }
.bg-success { background-color: #2ecc71; }
.bg-warning { background-color: #f39c12; }
.bg-danger { background-color: #e74c3c; }
.bg-info { background-color: #3498db; }
.bg-light { background-color: #f8f9fa; }
.bg-dark { background-color: #2c3e50; }

/* 边框 */
.border { border: 1px solid #dee2e6; }
.border-top { border-top: 1px solid #dee2e6; }
.border-right { border-right: 1px solid #dee2e6; }
.border-bottom { border-bottom: 1px solid #dee2e6; }
.border-left { border-left: 1px solid #dee2e6; }
.border-0 { border: 0; }
.border-top-0 { border-top: 0; }
.border-right-0 { border-right: 0; }
.border-bottom-0 { border-bottom: 0; }
.border-left-0 { border-left: 0; }

.rounded { border-radius: 0.25rem; }
.rounded-top { border-top-left-radius: 0.25rem; border-top-right-radius: 0.25rem; }
.rounded-right { border-top-right-radius: 0.25rem; border-bottom-right-radius: 0.25rem; }
.rounded-bottom { border-bottom-right-radius: 0.25rem; border-bottom-left-radius: 0.25rem; }
.rounded-left { border-top-left-radius: 0.25rem; border-bottom-left-radius: 0.25rem; }
.rounded-circle { border-radius: 50%; }
.rounded-0 { border-radius: 0; }

/* 阴影 */
.shadow-sm { box-shadow: 0 0.125rem 0.25rem rgba(0, 0, 0, 0.075); }
.shadow { box-shadow: 0 0.5rem 1rem rgba(0, 0, 0, 0.15); }
.shadow-lg { box-shadow: 0 1rem 3rem rgba(0, 0, 0, 0.175); }
.shadow-none { box-shadow: none; }