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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: #f2f2f7;
    color: #1c1c1e;
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

/* 苹果风导航栏 */
.navbar {
    background-color: #f2f2f7 !important;
    border-bottom: 1px solid #e0e0e0;
    box-shadow: 0 1px 3px rgba(0,0,0,0.05);
}

.navbar-brand {
    font-weight: 600;
    color: #007aff !important;
}

.nav-link {
    font-weight: 500;
    color: #1c1c1e !important;
    transition: color 0.2s ease;
}

.nav-link:hover {
    color: #007aff !important;
}

/* 苹果风卡片 */
.card {
    background-color: #ffffff;
    border: none;
    border-radius: 12px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.08);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}

/* 苹果风按钮 */
.btn {
    border-radius: 8px;
    font-weight: 500;
    padding: 8px 16px;
    transition: all 0.2s ease;
}

.btn-primary {
    background-color: #007aff;
    border: none;
}

.btn-primary:hover {
    background-color: #0066cc;
    transform: translateY(-1px);
}

.btn-outline-primary {
    border-color: #007aff;
    color: #007aff;
}

.btn-outline-primary:hover {
    background-color: #007aff;
    color: white;
}

.btn-outline-secondary {
    border-color: #c7c7cc;
    color: #8e8e93;
}

.btn-outline-secondary:hover {
    background-color: #f2f2f7;
    border-color: #8e8e93;
}

/* 苹果风表单元素 */
.form-control {
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    padding: 10px 12px;
    font-size: 14px;
    transition: all 0.2s ease;
}

.form-control:focus {
    border-color: #007aff;
    box-shadow: 0 0 0 2px rgba(0,122,255,0.2);
    outline: none;
}

.form-select {
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    padding: 10px 12px;
    font-size: 14px;
    transition: all 0.2s ease;
}

.form-select:focus {
    border-color: #007aff;
    box-shadow: 0 0 0 2px rgba(0,122,255,0.2);
    outline: none;
}

/* 苹果风输入组 */
.input-group {
    border-radius: 8px;
    overflow: hidden;
}

.input-group .btn {
    border-radius: 0 8px 8px 0;
}

.input-group .form-control {
    border-radius: 8px 0 0 8px;
    border-right: none;
}

/* 苹果风模态框 */
.modal-content {
    border-radius: 12px;
    border: none;
    box-shadow: 0 10px 30px rgba(0,0,0,0.15);
}

.modal-header {
    border-bottom: 1px solid #e0e0e0;
    padding: 16px 20px;
}

.modal-body {
    padding: 20px;
}

.modal-footer {
    border-top: 1px solid #e0e0e0;
    padding: 16px 20px;
}

/* 苹果风表格 */
.table {
    border-collapse: separate;
    border-spacing: 0;
    border-radius: 12px;
    overflow: hidden;
}

.table th {
    background-color: #f2f2f7;
    font-weight: 600;
    color: #1c1c1e;
    padding: 12px 16px;
    border-bottom: 1px solid #e0e0e0;
}

.table td {
    padding: 12px 16px;
    border-bottom: 1px solid #e0e0e0;
}

.table tr:last-child td {
    border-bottom: none;
}

.table-hover tr:hover {
    background-color: #f2f2f7;
}

/* 苹果风状态标签 */
.status-active {
    color: #34c759;
    font-weight: 500;
}

.status-inactive {
    color: #ff3b30;
    font-weight: 500;
}

/* 苹果风操作按钮 */
.action-buttons {
    display: flex;
    gap: 8px;
}

.edit-btn {
    background-color: #007aff;
    border: none;
    border-radius: 6px;
    padding: 6px 12px;
    font-size: 14px;
    color: white;
    cursor: pointer;
    transition: all 0.2s ease;
}

.edit-btn:hover {
    background-color: #0066cc;
    transform: translateY(-1px);
}

.delete-btn {
    background-color: #ff3b30;
    border: none;
    border-radius: 6px;
    padding: 6px 12px;
    font-size: 14px;
    color: white;
    cursor: pointer;
    transition: all 0.2s ease;
}

.delete-btn:hover {
    background-color: #cc0000;
    transform: translateY(-1px);
}

/* 苹果风消息提示 */
.error-message {
    color: #ff3b30;
    font-size: 14px;
    margin-top: 8px;
    text-align: center;
}

.success-message {
    color: #34c759;
    font-size: 14px;
    margin-top: 8px;
    text-align: center;
}

/* 苹果风链接 */
.back-link {
    display: inline-block;
    margin-bottom: 20px;
    color: #007aff;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s ease;
}

.back-link:hover {
    color: #0066cc;
    text-decoration: underline;
}

/* 苹果风课件卡片 */
#ppt-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
    margin-top: 20px;
}

#ppt-grid .card {
    background-color: #ffffff;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 2px 10px rgba(0,0,0,0.08);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

#ppt-grid .card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}

#ppt-grid .card-body {
    padding: 20px;
}

#ppt-grid .card-title {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 12px;
    color: #1c1c1e;
}

#ppt-grid .card-text {
    font-size: 14px;
    color: #8e8e93;
    margin-bottom: 16px;
}

#ppt-grid .card-footer {
    background-color: #f9f9f9;
    border-top: 1px solid #e0e0e0;
    padding: 16px;
}

/* 苹果风响应式设计 */
@media (max-width: 768px) {
    .container {
        padding: 16px;
    }
    
    #ppt-grid {
        grid-template-columns: 1fr;
    }
    
    .card {
        margin-bottom: 16px;
    }
}

/* 苹果风动画效果 */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.card {
    animation: fadeIn 0.3s ease;
}

/* 苹果风滚动条 */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: #f2f2f7;
}

::-webkit-scrollbar-thumb {
    background: #c7c7cc;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: #8e8e93;
}