// 容器类
.flex { display: flex; }
.inline-flex { display: inline-flex; }

// 方向类
.flex-row { flex-direction: row; }
.flex-col { flex-direction: column; }
.flex-row-reverse { flex-direction: row-reverse; }
.flex-col-reverse { flex-direction: column-reverse; }

// 换行类
.flex-wrap { flex-wrap: wrap; }
.flex-nowrap { flex-wrap: nowrap; }

.justify-start { justify-content: flex-start; }
.justify-center { justify-content: center; }
.justify-end { justify-content: flex-end; }
.justify-between { justify-content: space-between; }
.justify-around { justify-content: space-around; }

.items-start { align-items: flex-start; }
.items-center { align-items: center; }
.items-end { align-items: flex-end; }
.items-stretch { align-items: stretch; }
.items-baseline { align-items: baseline; }

// 顶部对齐
.flex-top-left { @extend .flex, .items-start, .justify-start; }
.flex-top-center { @extend .flex, .items-start, .justify-center; }
.flex-top-right { @extend .flex, .items-start, .justify-end; }

// 垂直居中对齐
.flex-middle-left { @extend .flex, .items-center, .justify-start; }
.flex-center { @extend .flex, .items-center, .justify-center; }
.flex-middle-right { @extend .flex, .items-center, .justify-end; }

// 底部对齐
.flex-bottom-left { @extend .flex, .items-end, .justify-start; }
.flex-bottom-center { @extend .flex, .items-end, .justify-center; }
.flex-bottom-right { @extend .flex, .items-end, .justify-end; }

// 拉伸对齐
.flex-stretch { @extend .flex, .items-stretch; }

// 弹性类
.flex-between-center { @extend .flex, .justify-between, .items-center; }
.flex-around-center { @extend .flex, .justify-around, .items-center; }

.flex-1 { flex: 1; }
.flex-auto { flex: auto; }
.flex-none { flex: none; }

.self-start { align-self: flex-start; }
.self-center { align-self: center; }
.self-end { align-self: flex-end; }
.self-stretch { align-self: stretch; }