header {
    background: white;
    padding: 20px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 100;
    border-bottom: 3px solid #1a73e8;
}

[data-theme="dark"] header {
    background: #2e3b3b;
    color: var(--text-color);
}

.header-content {
    max-width: 1300px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo-space {
    width: 80px;
    height: 80px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.logo-space img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.nav-menu {
    display: flex;
    align-items: center;
}

.nav-menu ul {
    display: flex;
    list-style: none;
}

.nav-menu ul li {
    margin-left: 35px;
}

.nav-menu ul li a {
    text-decoration: none;
    color: #333;
    font-weight: 700;
    font-size: 16px;
    transition: color 0.3s;
}

[data-theme="dark"] .nav-menu ul li a {
    color: var(--text-color);
}

.nav-menu ul li a:hover {
    color: #1a73e8;
}

[data-theme="dark"] .nav-menu ul li a:hover {
    color: var(--primary-color);
}

.hamburger-btn {
    display: none;
    padding: 10px;
    border: 2px solid #1a73e8;
    background: transparent;
    color: #1a73e8;
    border-radius: 25px;
    cursor: pointer;
    font-size: 18px;
}

[data-theme="dark"] .hamburger-btn {
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.hamburger-btn:hover {
    background: #1a73e8;
    color: white;
}

[data-theme="dark"] .hamburger-btn:hover {
    background: var(--primary-color);
    color: var(--text-color);
}

.theme-switcher {
    margin-left: 20px;
}

.action-btn {
    padding: 10px 20px;
    border: 2px solid #1a73e8;
    background: transparent;
    color: #1a73e8;
    border-radius: 25px;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.3s;
}

[data-theme="dark"] .action-btn {
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.action-btn:hover {
    background: #1a73e8;
    color: white;
}

[data-theme="dark"] .action-btn:hover {
    background: var(--primary-color);
    color: var(--text-color);
}

.action-btn.primary {
    background: #1a73e8;
    color: white;
}

[data-theme="dark"] .action-btn.primary {
    background: var(--primary-color);
    color: var(--text-color);
}

.action-btn.primary:hover {
    background: #0d47a1;
}

[data-theme="dark"] .action-btn.primary:hover {
    background: var(--secondary-color);
}

@media (max-width: 768px) {
    .header-content {
        flex-wrap: wrap;
        position: relative;
    }
    
    .hamburger-btn {
        display: block;
        order: 2;
        margin-left: auto;
    }
    
    .nav-menu {
        width: 100%;
        order: 3;
        display: none;
        margin-top: 20px;
    }
    
    .nav-menu.active {
        display: block;
    }
    
    .nav-menu ul {
        flex-direction: column;
        background: white;
        border-radius: 10px;
        box-shadow: 0 4px 15px rgba(0,0,0,0.1);
        padding: 20px;
    }
    
    [data-theme="dark"] .nav-menu ul {
        background: #2e3b3b;
    }
    
    .nav-menu ul li {
        margin: 10px 0;
        text-align: center;
    }
    
    .theme-switcher {
        order: 1;
        margin-left: 10px;
    }
}