/* 公共样式 */
main {
  background-color: #f2f4fa;
}

/* 隐藏滚动条但保持可滚动 */
::-webkit-scrollbar {
  width: 0;
  height: 0;
  background: transparent;
}

html {
  scrollbar-width: none; /* Firefox */
  -ms-overflow-style: none; /* IE and Edge */
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 15px;
}

/* 响应式布局基础类 */
@media screen and (max-width: 1920px) {
  .container {
    max-width: 1440px;
  }
}

@media screen and (max-width: 1440px) {
  .container {
    max-width: 1200px;
  }
}

@media screen and (max-width: 1200px) {
  .container {
    max-width: 960px;
  }
}

@media screen and (max-width: 992px) {
  .container {
    max-width: 720px;
  }
}

@media screen and (max-width: 768px) {
  .container {
    max-width: 540px;
  }
}

@media screen and (max-width: 576px) {
  .container {
    max-width: none;
    padding: 0 10px;
  }
}

/* 通用间距类 */
.mt-1 {
  margin-top: 0.25rem;
}
.mt-2 {
  margin-top: 0.5rem;
}
.mt-3 {
  margin-top: 1rem;
}
.mt-4 {
  margin-top: 1.5rem;
}
.mt-5 {
  margin-top: 3rem;
}

.mb-1 {
  margin-bottom: 0.25rem;
}
.mb-2 {
  margin-bottom: 0.5rem;
}
.mb-3 {
  margin-bottom: 1rem;
}
.mb-4 {
  margin-bottom: 1.5rem;
}
.mb-5 {
  margin-bottom: 3rem;
}

/* 通用按钮样式 */
.btn {
  display: inline-block;
  padding: 0.5rem 1rem;
  border-radius: 4px;
  cursor: pointer;
  transition: all 0.3s ease;
}

.btn-primary {
  background-color: #007bff;
  color: white;
}

.btn-primary:hover {
  background-color: #0056b3;
}

/* 通用文本样式 */
.text-center {
  text-align: center;
}
.text-left {
  text-align: left;
}
.text-right {
  text-align: right;
}

/* 通用flex布局类 */
.d-flex {
  display: flex;
}
.flex-wrap {
  flex-wrap: wrap;
}
.justify-content-between {
  justify-content: space-between;
}
.justify-content-center {
  justify-content: center;
}
.align-items-center {
  align-items: center;
}

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

.col {
  position: relative;
  width: 100%;
  padding-right: 15px;
  padding-left: 15px;
}

/* 响应式列类 */
@media (min-width: 576px) {
  .col-sm-6 {
    flex: 0 0 50%;
    max-width: 50%;
  }
  .col-sm-4 {
    flex: 0 0 33.333333%;
    max-width: 33.333333%;
  }
  .col-sm-3 {
    flex: 0 0 25%;
    max-width: 25%;
  }
}

@media (min-width: 768px) {
  .col-md-6 {
    flex: 0 0 50%;
    max-width: 50%;
  }
  .col-md-4 {
    flex: 0 0 33.333333%;
    max-width: 33.333333%;
  }
  .col-md-3 {
    flex: 0 0 25%;
    max-width: 25%;
  }
}

/* 懒加载图片样式 */
img[data-src], img[data-lazy] {
  background-color: #f5f5f5;
  background-image: linear-gradient(45deg, #f0f0f0 25%, transparent 25%),
                    linear-gradient(-45deg, #f0f0f0 25%, transparent 25%),
                    linear-gradient(45deg, transparent 75%, #f0f0f0 75%),
                    linear-gradient(-45deg, transparent 75%, #f0f0f0 75%);
  background-size: 20px 20px;
  background-position: 0 0, 0 10px, 10px -10px, -10px 0px;
  transition: opacity 0.3s ease;
}

img.loading {
  opacity: 0.7;
  animation: pulse 1.5s ease-in-out infinite;
}

img.loaded {
  opacity: 1;
  background: none;
}

img.error {
  background-color: #ffebee;
  background-image: none;
  position: relative;
}

img.error::after {
  content: '图片加载失败';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  color: #f44336;
  font-size: 12px;
  white-space: nowrap;
}

@keyframes pulse {
  0% { opacity: 0.7; }
  50% { opacity: 0.4; }
  100% { opacity: 0.7; }
}