/* 登录页 */
.login-page {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
}
.login-container {
    width: 100%;
    max-width: 420px;
    padding: 20px;
}
.login-card {
    background: white;
    border-radius: 16px;
    padding: 40px 30px;
    box-shadow: 0 20px 50px rgba(0,0,0,0.2);
}
.login-header h2 {
    font-weight: 700;
    color: #4e54c8;
    margin-bottom: 10px;
}

/* 侧边栏全局 */
.sidebar {
    background: linear-gradient(180deg, #2c3e50 0%, #34495e 100%);
    min-height: 100vh;
    padding-top: 20px;
    color: white;
}
.sidebar .list-group-item {
    background: transparent;
    border: none;
    color: rgba(255,255,255,0.8);
    font-size: 0.95rem;
    transition: 0.3s;
}
.sidebar .list-group-item:hover {
    background: rgba(255,255,255,0.1);
    color: white;
}
.sidebar .list-group-item.active {
    background: rgba(255,255,255,0.2);
    color: white;
    font-weight: 600;
    border-left: 4px solid #f1c40f;
}
.sidebar .submenu .list-group-item {
    padding-left: 3rem !important;
    font-size: 0.9rem;
}
.sidebar .collapse-btn::after {
    content: "\f078";
    font-family: "bootstrap-icons";
    float: right;
    transition: transform 0.3s;
}
.sidebar .collapse-btn.collapsed::after {
    transform: rotate(-90deg);
}
/* 退出按钮固定底部 */
.sidebar .mt-auto {
    margin-top: auto !important;
    border-top: 1px solid rgba(255,255,255,0.2);
}
/* 主内容区 */
main {
    padding: 20px;
    background: #f5f7fb;
    min-height: 100vh;
}
/* 移动端 offcanvas 侧边栏样式 */
.offcanvas-body .sidebar {
    min-height: auto;
    background: linear-gradient(180deg, #2c3e50 0%, #34495e 100%);
    padding: 15px;
}
/* 顶部导航 */
.navbar-brand {
    font-weight: bold;
}