* { box-sizing: border-box; font-family: 'Segoe UI', sans-serif; }
body { margin: 0; background: #f4f6f9; }

.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 75px;
    background: #006400; /* Deep Green */
    color: white;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 25px;
    z-index: 1000; /* Jate shobar upore thake */
    box-shadow: 0 2px 10px rgba(0,0,0,0.3);
}
.header img { height: 50px; background: white; padding: 3px; border-radius: 4px; }

.sidebar {
    position: fixed; left: 0; top: 75px; width: 260px;
    height: calc(100vh - 75px); background: #2c3e50;
    overflow-y: auto; z-index: 999;
}
.sidebar ul { list-style: none; padding: 0; margin: 0; }
.sidebar ul li a {
    color: #bdc3c7; text-decoration: none; display: block;
    padding: 15px 25px; border-bottom: 1px solid #34495e; transition: 0.3s;
}
.sidebar ul li a:hover { background: #34495e; color: white; padding-left: 35px; }

.main-content { margin-left: 260px; margin-top: 75px; padding: 30px; }
.card { background: white; padding: 25px; border-radius: 10px; box-shadow: 0 2px 10px rgba(0,0,0,0.05); }

table { width: 100%; border-collapse: collapse; margin-top: 20px; }
th, td { border: 1px solid #ddd; padding: 12px; text-align: left; }
th { background: #f8f9fa; color: #333; }
.btn { padding: 8px 15px; border-radius: 4px; text-decoration: none; color: white; cursor: pointer; border: none; font-size: 14px; }
.btn-delete { background: #e74c3c; }
.btn-edit { background: #f39c12; }
.btn-save { background: #006400; width: 100%; padding: 12px; font-weight: bold; margin-top: 10px;}
input, select { width: 100%; padding: 10px; margin: 10px 0; border: 1px solid #ccc; border-radius: 5px; }