* { box-sizing: border-box; }
body { margin: 0; font-family: Segoe UI, Arial, sans-serif; }

.header-fixo {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 50px;
    background: #b22222;
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 20px;
    z-index: 1000;
}

.header-left { font-weight: bold; font-size: 1.1em; }
.header-nav { display: flex; align-items: center; gap: 20px; }
.header-nav a { color: #fff; text-decoration: none; }
.header-nav a:hover { text-decoration: underline; }
.header-admin { font-weight: 600; }

.main-content {
    margin-top: 50px;
    min-height: calc(100vh - 50px);
    padding: 20px;
}

.form-centralizado {
    max-width: 400px;
    margin: 40px auto;
    padding: 30px;
    background: #f5f5f5;
    border: 2px solid #b22222;
    border-radius: 4px;
}

.form-centralizado h3 { text-align: center; margin-bottom: 20px; }
.form-group { margin-bottom: 15px; }
.form-group label { display: block; font-weight: bold; margin-bottom: 5px; }
.form-group input { width: 100%; padding: 8px; border: 1px solid #333; }
.btn-acessar, .btn-salvar {
    width: 100%;
    padding: 10px;
    background: #b22222;
    color: #fff;
    border: none;
    font-weight: bold;
    cursor: pointer;
    margin-top: 10px;
}
.btn-acessar:hover, .btn-salvar:hover { background: #8b0000; }

.erro-validacao {
    background: #f8d7da;
    color: #721c24;
    padding: 8px;
    margin-bottom: 10px;
    font-size: 14px;
}

@media (max-width: 600px) {
    .header-fixo { flex-wrap: wrap; height: auto; padding: 10px; }
    .header-nav { flex-wrap: wrap; }
}