.site-header {
    background: #ffffff;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
    position: sticky;
    top: 0;
    z-index: 1000;
    padding: 15px 0;
}
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
}
.header-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.site-branding {
    display: flex;
    align-items: center;
    gap: 10px;
}
.site-logo {
    max-height: 40px;
    width: auto;
    object-fit: contain;
}
.site-title {
    font-size: 24px;
    font-weight: 700;
    color: #1a1a1a;
    text-decoration: none;
    font-family: 'Ubuntu', sans-serif;
    transition: color 0.3s ease;
    margin: 0;
}
.site-title:hover {
    color: #4a5568;
}
.main-navigation {
    display: flex;
    align-items: center;
    gap: 15px;
}
.nav-menu {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    gap: 25px;
}
.nav-menu li {
    position: relative;
}
.nav-menu > li > a {
    text-decoration: none;
    color: #4a5568;
    font-weight: 500;
    font-size: 15px;
    font-family: 'Ubuntu', sans-serif;
    transition: color 0.3s ease;
    padding: 8px 0;
    display: block;
}
.nav-menu > li > a:hover {
    color: #1a1a1a;
}
.nav-menu .menu-item-has-children > a:after {
    content: '\f107';
    font-family: 'Font Awesome 6 Free';
    font-weight: 900;
    font-size: 10px;
    margin-left: 6px;
    display: inline-block;
    transition: transform 0.3s ease;
}
.nav-menu .menu-item-has-children:hover > a:after {
    transform: rotate(180deg);
}
.nav-menu .sub-menu {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    background: #ffffff;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    list-style: none;
    padding: 10px 0;
    min-width: 200px;
    z-index: 1000;
    border-radius: 6px;
    border-top: 2px solid #4a5568;
}
.nav-menu li:hover > .sub-menu {
    display: block;
}
.nav-menu .sub-menu li {
    margin: 0;
}
.nav-menu .sub-menu a {
    color: #4a5568;
    font-weight: 400;
    font-size: 14px;
    padding: 8px 15px;
    display: block;
    transition: background 0.3s ease, color 0.3s ease;
}
.nav-menu .sub-menu a:hover {
    background: #f5f5f5;
    color: #1a1a1a;
}
.menu-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 22px;
    color: #1a1a1a;
    cursor: pointer;
    padding: 5px;
    transition: color 0.3s ease;
    position: relative;
    z-index: 1001;
}
.menu-toggle.active i.fa-bars {
    display: none;
}
.menu-toggle.active:before {
    content: '\f00d';
    font-family: 'Font Awesome 6 Free';
    font-weight: 900;
    font-size: 22px;
}
.dark-mode-container {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    background: rgba(255, 255, 255, 0.8);
    border-radius: 50%;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}
.dark-mode-toggle {
    background: none;
    border: none;
    font-size: 22px;
    color: #1a1a1a;
    cursor: pointer;
    padding: 0;
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: color 0.3s ease;
}
.dark-mode-toggle:hover {
    color: #4a5568;
}
.dark-mode-toggle.active {
    transform: rotate(360deg);
    transition: transform 0.5s ease, color 0.3s ease;
}
.dark-mode-toggle.active i.fa-moon {
    display: none;
}
.dark-mode-toggle.active:before {
    content: '\f185';
    font-family: 'Font Awesome 6 Free';
    font-weight: 900;
    font-size: 22px;
}
@media (max-width: 768px) {
    .menu-toggle {
        display: block;
        position: fixed;
        top: 15px;
        right: 50px;
    }
    .dark-mode-container {
        position: fixed;
        top: 15px;
        right: 15px;
        z-index: 1001;
    }
    .nav-menu {
        display: none;
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100vh;
        background: #ffffff;
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 20px;
        padding: 20px 0;
        z-index: 999;
        transition: transform 0.3s ease;
        transform: translateX(-100%);
    }
    .nav-menu.active {
        display: flex;
        transform: translateX(0);
    }
    .nav-menu > li > a {
        font-size: 20px;
        padding: 10px;
        color: #1a1a1a;
    }
    .nav-menu .menu-item-has-children > a:after {
        content: '\f107';
        font-family: 'Font Awesome 6 Free';
        font-weight: 900;
        font-size: 14px;
        margin-left: 8px;
    }
    .nav-menu .menu-item-has-children.active > a:after {
        transform: rotate(180deg);
    }
    .nav-menu .sub-menu {
        position: static;
        box-shadow: none;
        background: #f5f5f5;
        padding: 5px 0;
        width: 100%;
        display: none;
        border-radius: 0;
        border-top: none;
    }
    .nav-menu li:hover > .sub-menu {
        display: none;
    }
    .nav-menu li.active > .sub-menu {
        display: block;
    }
    .nav-menu .sub-menu a {
        font-size: 16px;
        padding: 8px 15px;
        text-align: center;
    }
    .header-inner {
        flex-direction: row;
        align-items: center;
    }
    .site-logo {
        max-height: 35px;
    }
    .site-title {
        font-size: 20px;
    }
}
@media (max-width: 480px) {
    .site-logo {
        max-height: 30px;
    }
    .site-title {
        font-size: 18px;
    }
    .menu-toggle {
        font-size: 20px;
    }
    .menu-toggle.active:before {
        font-size: 20px;
    }
    .dark-mode-container {
        width: 32px;
        height: 32px;
    }
    .dark-mode-toggle {
        font-size: 20px;
    }
    .dark-mode-toggle.active:before {
        font-size: 20px;
    }
    .nav-menu > li > a {
        font-size: 18px;
    }
    .nav-menu .sub-menu a {
        font-size: 14px;
    }
}