/* Header Styles */
header {
    background: var(--primary);
    color: white;
    padding: 0;
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.header-top {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 5%;
    background: var(--dark);
}

.logo {
    font-size: 1.8rem;
    font-weight: bold;
    color: white;
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo i {
    color: var(--secondary);
}

.nav-main ul {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-main a {
    color: white;
    text-decoration: none;
    transition: color 0.3s;
    font-weight: 500;
}

.nav-main a.active {
    color: var(--secondary);
    font-weight: bold;
}

.auth-buttons {
    display: flex;
    gap: 1rem;
}

.header-bottom {
    display: flex;
    justify-content: center;
    padding: 0.8rem 5%;
    background: var(--primary);
    border-top: 1px solid rgba(255,255,255,0.1);
}

.operation-tabs {
    display: flex;
    gap: 0;
    border-radius: 5px;
    overflow: hidden;
}

.operation-tab {
    padding: 0.7rem 1.5rem;
    background: rgba(255,255,255,0.1);
    color: white;
    border: none;
    cursor: pointer;
    transition: all 0.3s;
}

.operation-tab.active {
    background: var(--accent);
}