.common-header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: var(--bg-card, #ffffff);
    border-bottom: 1px solid var(--border-color, #d0d7de);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
    padding: 10px 0;
}

.tool-nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 24px;
    flex-wrap: wrap;
}

.tool-nav-left,
.tool-nav-right {
    display: flex;
    align-items: center;
    gap: 12px;
    flex-shrink: 0;
}

.tool-logo {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    flex-shrink: 0;
    margin-right: 20px;
}

.tool-logo-img {
    width: 110px;
    height: auto;
    object-fit: contain;
}

.tool-logo-title {
    font-size: 1.05rem;
    font-weight: 600;
    color: var(--text-primary, #333333);
    white-space: nowrap;
}

.tool-nav-items {
    flex: 1;
    display: flex;
    align-items: center;
    gap: 8px;
    flex-wrap: wrap;
    justify-content: flex-start;
    min-width: 0;
}

.toolbox-link,
.tool-nav-items a {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 7px 14px;
    border-radius: 20px;
    border: 1px solid var(--border-color, #d0d7de);
    color: var(--text-secondary, #57606a);
    background: transparent;
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.2s ease;
    white-space: nowrap;
}

.toolbox-link:hover,
.tool-nav-items a:hover {
    color: var(--accent-color, #0969da);
    border-color: var(--accent-color, #0969da);
    background: rgba(9, 105, 218, 0.08);
}

.tool-nav-items a.active {
    background: var(--accent-color, #0969da);
    color: #fff;
    border-color: var(--accent-color, #0969da);
    box-shadow: 0 2px 6px rgba(9, 105, 218, 0.25);
}

.common-theme-toggle {
    background: transparent;
    border: 1px solid var(--border-color, #d0d7de);
    border-radius: 50%;
    width: 36px;
    height: 36px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    color: #f59e0b;
    transition: all 0.2s ease;
    flex-shrink: 0;
}

.common-theme-toggle.theme-dark {
    color: #9ca3af;
}

.common-theme-toggle:hover {
    color: #fbbf24;
    border-color: #f59e0b;
    background: rgba(245, 158, 11, 0.12);
}

.common-theme-toggle.theme-dark:hover {
    color: #d1d5db;
    border-color: #9ca3af;
    background: rgba(156, 163, 175, 0.12);
}

@media (max-width: 768px) {
    .tool-nav {
        justify-content: center;
        padding: 0 16px;
    }

    .tool-logo {
        margin-right: 0;
    }

    .tool-logo-img {
        width: 90px;
    }

    .tool-nav-items {
        order: 3;
        width: 100%;
        justify-content: center;
    }

    .tool-nav-left,
    .tool-nav-right {
        order: 1;
    }
}