/* ==========================================================================
   Footer Styles
   ========================================================================== 
   
   Architecture:
   - Glassmorphism matching navigation
   - Rounded top edges
   - 4-column responsive grid
   - Brand with "Portfolio." (red dot)
   - Smooth hover animations using transform/opacity
   
   ========================================================================== */

.footer {
    background: var(--glass-bg);
    -webkit-backdrop-filter: var(--glass-blur);
    backdrop-filter: var(--glass-blur);
    border-top-left-radius: var(--radius-3xl);
    border-top-right-radius: var(--radius-3xl);
    margin-top: var(--space-20);
    padding: var(--space-12) 0 var(--space-6);
    border-top: var(--glass-border);
    
    /* Theme transitions */
    transition: 
        background var(--duration-slow) var(--ease-in-out),
        border-color var(--duration-slow) var(--ease-in-out);
}

.footer__container {
    max-width: var(--container-xl);
    margin: 0 auto;
    padding: 0 var(--space-6);
}

.footer__grid {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr 1fr;
    gap: var(--space-8);
    margin-bottom: var(--space-8);
}

/* ==========================================================================
   BRAND SECTION - "Portfolio." with red dot
   ========================================================================== */

.footer__brand {
    max-width: 320px;
}

.footer__logo {
    display: flex;
    align-items: baseline;
    margin-bottom: var(--space-3);
}

.footer__logo-text {
    font-family: var(--font-family-sans);
    font-size: var(--font-size-2xl);
    font-weight: var(--font-weight-bold);
    color: var(--color-text);
    letter-spacing: var(--letter-spacing-tight);
}

.footer__logo-dot {
    font-family: var(--font-family-serif);
    font-size: var(--font-size-2xl);
    font-weight: var(--font-weight-bold);
    font-style: italic;
    color: var(--color-tertiary); /* Red dot */
    margin-left: -2px;
}

.footer__tagline {
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    line-height: var(--line-height-relaxed);
}

/* ==========================================================================
   SECTION TITLES
   ========================================================================== */

.footer__title {
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-semibold);
    text-transform: uppercase;
    letter-spacing: var(--letter-spacing-wide);
    margin-bottom: var(--space-4);
    color: var(--color-text);
}

/* ==========================================================================
   QUICK LINKS
   ========================================================================== */

.footer__links ul {
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
    margin: 0;
    padding: 0;
    list-style: none;
}

.footer__links a {
    display: inline-block;
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    text-decoration: none;
    
    transition: 
        color var(--duration-normal) var(--ease-in-out),
        transform var(--duration-fast) var(--ease-out);
}

.footer__links a:hover {
    color: var(--color-primary);
    transform: translateX(4px);
}

.footer__links a:focus-visible {
    outline: var(--focus-ring-width) solid var(--color-focus-ring);
    outline-offset: var(--focus-ring-offset);
    border-radius: var(--radius-sm);
}

/* ==========================================================================
   SOCIAL LINKS
   ========================================================================== */

.footer__social-links {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-2);
}

.footer__social-links a {
    width: var(--space-10); /* 40px */
    height: var(--space-10);
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-full);
    background-color: var(--color-surface-secondary);
    color: var(--color-text-secondary);
    text-decoration: none;
    
    /* Performance-optimized transitions */
    transition: 
        background-color var(--duration-normal) var(--ease-in-out),
        color var(--duration-normal) var(--ease-in-out),
        transform var(--duration-fast) var(--ease-out);
}

.footer__social-links a:hover {
    background-color: var(--color-primary);
    color: var(--color-text-inverse);
    transform: translateY(-2px);
}

.footer__social-links a:focus-visible {
    outline: var(--focus-ring-width) solid var(--color-focus-ring);
    outline-offset: var(--focus-ring-offset);
}

.footer__social-links svg,
.footer__social-links i {
    width: var(--icon-size-sm); /* 18px */
    height: var(--icon-size-sm);
    stroke-width: var(--icon-stroke-default);
}

/* ==========================================================================
   CONTACT
   ========================================================================== */

.footer__contact {
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
}

.footer__contact a {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    text-decoration: none;
    
    transition: 
        color var(--duration-normal) var(--ease-in-out),
        transform var(--duration-fast) var(--ease-out);
}

.footer__contact a:hover {
    color: var(--color-primary);
    transform: translateX(4px);
}

.footer__contact a:focus-visible {
    outline: var(--focus-ring-width) solid var(--color-focus-ring);
    outline-offset: var(--focus-ring-offset);
    border-radius: var(--radius-sm);
}

.footer__contact svg,
.footer__contact i {
    width: var(--icon-size-sm);
    height: var(--icon-size-sm);
    flex-shrink: 0;
    stroke-width: var(--icon-stroke-default);
}

/* ==========================================================================
   BOTTOM BAR
   ========================================================================== */

.footer__bottom {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    align-items: center;
    gap: var(--space-4);
    padding-top: var(--space-6);
    border-top: 1px solid var(--color-border-subtle);
}

.footer__bottom p {
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
    margin: 0;
}

.footer__legal {
    display: flex;
    gap: var(--space-4);
}

.footer__legal a {
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
    text-decoration: none;
    
    transition: color var(--duration-normal) var(--ease-in-out);
}

.footer__legal a:hover {
    color: var(--color-primary);
}

.footer__legal a:focus-visible {
    outline: var(--focus-ring-width) solid var(--color-focus-ring);
    outline-offset: var(--focus-ring-offset);
    border-radius: var(--radius-sm);
}

/* ==========================================================================
   RESPONSIVE - Tablet (< 1024px)
   ========================================================================== */

@media (max-width: 1023px) {
    .footer__grid {
        grid-template-columns: 1fr 1fr;
    }
    
    .footer__brand {
        grid-column: 1 / -1;
        max-width: none;
        text-align: center;
        margin-bottom: var(--space-4);
    }
    
    .footer__logo {
        justify-content: center;
    }
}

/* ==========================================================================
   RESPONSIVE - Mobile (< 768px)
   ========================================================================== */

@media (max-width: 767px) {
    .footer {
        padding: var(--space-8) 0 var(--space-4);
        border-top-left-radius: var(--radius-2xl);
        border-top-right-radius: var(--radius-2xl);
    }
    
    .footer__container {
        padding: 0 var(--space-4);
    }

    .footer__grid {
        grid-template-columns: 1fr;
        gap: var(--space-6);
        text-align: center;
    }

    .footer__brand {
        margin-bottom: var(--space-2);
    }
    
    .footer__links ul {
        align-items: center;
    }

    .footer__social-links {
        justify-content: center;
    }
    
    .footer__contact {
        align-items: center;
    }
    
    .footer__contact a:hover {
        transform: none;
    }

    .footer__bottom {
        flex-direction: column;
        text-align: center;
        gap: var(--space-3);
    }
    
    .footer__legal {
        justify-content: center;
    }
}

/* Visually hidden helper for screen readers */
.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}