/* Header - Minimal */
header {
    background: var(--bg-color);
    color: var(--text-color);
    padding: 1rem 2rem;
    position: fixed;
    width: 100%;
    top: 0;
    left: 0;
    z-index: 1000;
    border-bottom: 1px solid var(--border-color);
    transition: background-color 0.3s ease, border-color 0.3s ease;
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
}

nav ul {
    list-style: none;
    display: flex;
    justify-content: flex-start;
    padding: 0;
    align-items: center;
    gap: 0.5rem;
}

nav ul li {
    margin: 0;
    padding: 0;
}

nav ul li a {
    color: var(--text-color);
    text-decoration: none;
    padding: 0.4rem 0.8rem;
    transition: color 0.2s ease, background-color 0.2s ease;
    font-weight: 400;
    font-size: 0.95rem;
    display: inline-block;
    border-radius: 4px;
}

nav ul li a:hover,
nav ul li a:focus {
    color: var(--bg-color);
    background-color: var(--accent-color);
}

/* Theme Toggle Button */
.theme-toggle {
    background: none;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 8px;
    cursor: pointer;
    color: var(--text-color);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background-color 0.2s ease, border-color 0.2s ease, color 0.2s ease;
}

.theme-toggle:hover {
    background-color: var(--accent-color);
    color: var(--bg-color);
    border-color: var(--accent-color);
}

.theme-toggle svg {
    width: 18px;
    height: 18px;
}

/* Show/hide icons based on theme */
.sun-icon { display: none; }
.moon-icon { display: block; }

[data-theme="dark"] .sun-icon { display: block; }
[data-theme="dark"] .moon-icon { display: none; }

@media (max-width: 600px) {
    header {
        padding: 0.75rem 1rem;
    }

    nav ul {
        gap: 0.25rem;
    }

    nav ul li a {
        font-size: 0.85rem;
        padding: 0.3rem 0.5rem;
    }

    .theme-toggle {
        padding: 6px;
    }

    .theme-toggle svg {
        width: 16px;
        height: 16px;
    }
}