/* ============================================
   Responsive Design - Mobile First
   ============================================ */

/* Mobile Styles (< 640px) */
@media (max-width: 639px) {

    /* Prevent leftover horizontal scrolling on small screens */
    html,
    body {
        overflow-x: hidden;
        min-width: 0;
    }

    :root {
        --font-size-base: 0.9375rem;
        --font-size-lg: 1rem;
        --font-size-xl: 1.125rem;
    }

    body {
        font-size: var(--font-size-base);
    }

    .page {
        padding: var(--spacing-md);
    }

    /* Slightly reduce container horizontal padding on smallest screens */
    .container {
        padding: 0 calc(var(--spacing-sm) / 2);
    }

    /* Mobile Navigation */
    .sidebar {
        position: fixed;
        left: -100%;
        top: 0;
        width: 100%;
        height: 100vh;
        background-color: var(--bg-primary);
        z-index: var(--z-modal);
        transition: left var(--transition-base);
    }

    .sidebar.open {
        left: 0;
    }

    /* Mobile Grid */
    .grid {
        grid-template-columns: 1fr;
    }

    .grid-2 {
        grid-template-columns: 1fr;
    }

    .grid-3 {
        grid-template-columns: 1fr;
    }

    /* Mobile Forms */
    input,
    textarea,
    select {
        font-size: 16px;
        /* Prevents zoom on iOS */
        padding: var(--spacing-md);
    }

    button {
        min-height: 44px;
        min-width: 44px;
        padding: var(--spacing-md) var(--spacing-lg);
    }

    /* Stack action buttons vertically on small screens for better touch targets */
    .article-actions {
        display: flex;
        flex-direction: column;
        gap: var(--spacing-sm);
    }

    .article-actions .btn {
        width: 100%;
    }

    /* Mobile Typography */
    h1 {
        font-size: var(--font-size-2xl);
    }

    h2 {
        font-size: var(--font-size-xl);
    }

    h3 {
        font-size: var(--font-size-lg);
    }

    /* Hide desktop elements */
    .desktop-only {
        display: none;
    }

    /* Show mobile elements */
    .mobile-only {
        display: block;
    }
}

/* Tablet Styles (640px - 1024px) */
@media (min-width: 640px) and (max-width: 1023px) {
    :root {
        --font-size-base: 0.9375rem;
    }

    .page {
        padding: var(--spacing-lg);
    }

    .container {
        padding: 0 var(--spacing-md);
    }

    /* Tablet Grid */
    .grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .grid-3 {
        grid-template-columns: repeat(2, 1fr);
    }

    /* Hide mobile-only elements */
    .mobile-only {
        display: none;
    }

    /* Show desktop elements */
    .desktop-only {
        display: block;
    }
}

/* Desktop Styles (>= 1024px) */
@media (min-width: 1024px) {
    .page {
        padding: var(--spacing-xl);
    }

    .container {
        padding: 0 var(--spacing-lg);
    }

    /* Desktop Grid */
    .grid {
        grid-template-columns: repeat(3, 1fr);
    }

    .grid-2 {
        grid-template-columns: repeat(2, 1fr);
    }

    .grid-3 {
        grid-template-columns: repeat(3, 1fr);
    }

    /* Desktop Layout */
    .sidebar {
        position: static;
        width: auto;
        height: auto;
        background-color: transparent;
    }

    /* Hide mobile-only elements */
    .mobile-only {
        display: none;
    }

    /* Show desktop elements */
    .desktop-only {
        display: block;
    }
}

/* Large Desktop (>= 1280px) */
@media (min-width: 1280px) {
    .container {
        max-width: 1280px;
    }
}

/* Extra Large Desktop (>= 1536px) */
@media (min-width: 1536px) {
    .container {
        max-width: 1536px;
    }
}

/* Touch Device Optimizations */
@media (hover: none) and (pointer: coarse) {

    button,
    a,
    input,
    textarea,
    select {
        min-height: 44px;
        min-width: 44px;
    }

    button {
        padding: var(--spacing-md) var(--spacing-lg);
    }

    /* Increase touch target spacing */
    .btn-group button {
        margin: var(--spacing-sm);
    }
}

/* Landscape Orientation */
@media (orientation: landscape) and (max-height: 500px) {
    .page {
        padding: var(--spacing-sm);
    }

    h1 {
        font-size: var(--font-size-xl);
    }

    h2 {
        font-size: var(--font-size-lg);
    }
}

/* High DPI Screens */
@media (-webkit-min-device-pixel-ratio: 2),
(min-resolution: 192dpi) {

    /* Optimize for high DPI displays */
    body {
        -webkit-font-smoothing: subpixel-antialiased;
    }
}

/* Reduced Motion */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* Print Styles */
@media print {
    body {
        background-color: white;
        color: black;
    }

    .no-print {
        display: none;
    }

    a {
        text-decoration: underline;
    }
}