:root {
    --primary: #113F67;
    --secondary: #34699A;
    --accent: #58A0C8;
    --light: #FDF5AA;
    --white: #ffffff;
    --dark: #1a1a1a;
    --gray: #f5f5f5;
    --text: #333;
    --border: #ddd;
}

[data-theme="dark"] {
    --white: #1a1a1a;
    --gray: #2d2d2d;
    --text: #ffffff;
    --border: #444;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: var(--gray);
    color: var(--text);
    transition: all 0.3s ease;
}

.header-container {
    background: var(--primary);
    color: var(--white);
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.header-brand {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.header-logo {
    width: 50px;
    height: 50px;
    border-radius: 50%;
}

.header-text h1 {
    font-size: 1.5rem;
    margin-bottom: 0.2rem;
}

.header-text p {
    font-size: 0.9rem;
    opacity: 0.8;
}

.header-user {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.header-theme-toggle {
    background: none;
    border: none;
    font-size: 1.2rem;
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 50%;
    transition: background 0.3s ease;
}

.header-theme-toggle:hover {
    background: rgba(255,255,255,0.1);
}

.header-logout {
    color: var(--light);
    text-decoration: none;
    padding: 0.5rem 1rem;
    border-radius: 5px;
    transition: background 0.3s ease;
}

.header-logout:hover {
    background: rgba(255,255,255,0.1);
}

@media (max-width: 768px) {
    .header-container {
        padding: 1rem;
        flex-direction: column;
        gap: 1rem;
    }
    
    .header-text h1 {
        font-size: 1.2rem;
    }
    
    .header-text p {
        font-size: 0.8rem;
    }
}