/* ═══════════════════════════════════════════════════════════════════════════════
   SGraph Send — Header Styles
   v0.2.0 — Aurora dark theme, aligned with sgraph.ai (1200px)
   ═══════════════════════════════════════════════════════════════════════════════ */

.sg-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--space-4, 1rem) var(--space-6, 1.5rem);
    max-width: 1200px;
    margin: 0 auto;
}

.sg-header__brand {
    display: flex;
    align-items: center;
    gap: var(--space-3, 0.75rem);
}

.sg-header__favicon {
    width: 28px;
    height: 28px;
    flex-shrink: 0;
}

.sg-header__logo {
    text-decoration: none;
    font-size: 1.5rem;
    font-weight: var(--weight-bold, 700);
    letter-spacing: -0.02em;
    display: flex;
    align-items: center;
    gap: 2px;
}

.sg-header__logo:hover {
    text-decoration: none;
}

.sg-header__logo-sg {
    color: var(--accent, #4ECDC4);
}

.sg-header__logo-sep {
    color: var(--color-text-secondary, #8892A0);
    font-weight: var(--weight-regular, 400);
}

.sg-header__logo-send {
    color: var(--color-text, #E0E0E0);
}

.sg-header__tagline {
    font-size: var(--text-small, 0.8rem);
    color: var(--color-text-secondary, #8892A0);
}

.sg-header__nav {
    display: flex;
    align-items: center;
    gap: var(--space-6, 1.5rem);
}

.sg-header__nav a {
    color: var(--color-text-secondary, #8892A0);
    font-weight: 500;
    font-size: 0.95rem;
    text-decoration: none;
    transition: color 150ms ease;
}

.sg-header__nav a:hover {
    color: #FFFFFF;
}

@media (max-width: 640px) {
    .sg-header {
        flex-direction: column;
        gap: var(--space-2, 0.5rem);
        text-align: center;
    }
    .sg-header__tagline {
        display: none;
    }
    .sg-header__favicon {
        width: 24px;
        height: 24px;
    }
}
