/* ===== NIRIV MOBILE-FIRST FRAMEWORK ===== */
/* Inspired by Naver's mobile design principles */
/* Mobile-first responsive design with progressive enhancement */

/* ===== CSS CUSTOM PROPERTIES (VARIABLES) ===== */
:root {
    /* Mobile-First Breakpoints */
    --bp-xs: 320px;    /* Extra small phones */
    --bp-sm: 640px;    /* Small phones */
    --bp-md: 768px;    /* Tablets */
    --bp-lg: 1024px;   /* Small laptops */
    --bp-xl: 1280px;   /* Large laptops */
    --bp-2xl: 1536px;  /* Desktop monitors */
    
    /* Container Max Widths (Mobile-First) */
    --container-xs: 100%;
    --container-sm: 640px;
    --container-md: 768px;
    --container-lg: 1024px;
    --container-xl: 1100px;
  --container-2xl: 1100px;
    
    /* Spacing Scale (Mobile-First) */
    --space-xs: 0.25rem;   /* 4px */
    --space-sm: 0.5rem;    /* 8px */
    --space-md: 1rem;      /* 16px */
    --space-lg: 1.5rem;    /* 24px */
    --space-xl: 2rem;      /* 32px */
    --space-2xl: 3rem;     /* 48px */
    --space-3xl: 4rem;     /* 64px */
    
    /* Typography Scale (Mobile-First) */
    --text-xs: 0.75rem;    /* 12px */
    --text-sm: 0.875rem;   /* 14px */
    --text-base: 1rem;     /* 16px */
    --text-lg: 1.125rem;   /* 18px */
    --text-xl: 1.25rem;    /* 20px */
    --text-2xl: 1.5rem;    /* 24px */
    --text-3xl: 1.875rem;  /* 30px */
    --text-4xl: 2.25rem;   /* 36px */
    
    /* Touch-Friendly Sizing */
    --touch-min: 44px;     /* Minimum touch target */
    --touch-comfortable: 48px;
    --touch-large: 56px;
    
    /* Border Radius */
    --radius-sm: 0.25rem;  /* 4px */
    --radius-md: 0.5rem;   /* 8px */
    --radius-lg: 1rem;     /* 16px */
    --radius-xl: 1.5rem;   /* 24px */
    --radius-2xl: 2rem;    /* 32px */
    --radius-full: 9999px;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
    
    /* Animation Timing */
    --transition-fast: 0.15s ease-out;
    --transition-normal: 0.3s ease-out;
    --transition-slow: 0.5s ease-out;
}

/* ===== MOBILE-FIRST CONTAINER SYSTEM ===== */
.niriv-container {
    width: 100%;
    margin-left: auto;
    margin-right: auto;
    padding-left: var(--space-md);
    padding-right: var(--space-md);
}

/* Progressive Enhancement for Larger Screens */
@media (min-width: 640px) {
    .niriv-container {
        max-width: var(--container-sm);
        padding-left: var(--space-lg);
        padding-right: var(--space-lg);
    }
}

@media (min-width: 768px) {
    .niriv-container {
        max-width: var(--container-md);
        padding-left: var(--space-xl);
        padding-right: var(--space-xl);
    }
}

@media (min-width: 1024px) {
    .niriv-container {
        max-width: var(--container-lg);
    }
}

@media (min-width: 1280px) {
    .niriv-container {
        max-width: var(--container-xl);
    }
}

@media (min-width: 1536px) {
    .niriv-container {
        max-width: var(--container-2xl);
    }
}

/* ===== MOBILE-FIRST GRID SYSTEM ===== */
.niriv-grid {
    display: grid;
    gap: var(--space-md);
    grid-template-columns: 1fr; /* Mobile: Single column */
}

@media (min-width: 640px) {
    .niriv-grid-sm-2 {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (min-width: 768px) {
    .niriv-grid-md-2 {
        grid-template-columns: repeat(2, 1fr);
    }
    .niriv-grid-md-3 {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (min-width: 1024px) {
    .niriv-grid-lg-3 {
        grid-template-columns: repeat(3, 1fr);
    }
    .niriv-grid-lg-4 {
        grid-template-columns: repeat(4, 1fr);
    }
}

/* ===== MOBILE-FIRST TYPOGRAPHY ===== */
.niriv-text-responsive {
    font-size: var(--text-sm);
    line-height: 1.5;
}

@media (min-width: 640px) {
    .niriv-text-responsive {
        font-size: var(--text-base);
    }
}

@media (min-width: 768px) {
    .niriv-text-responsive {
        font-size: var(--text-lg);
    }
}

.niriv-heading-responsive {
    font-size: var(--text-xl);
    line-height: 1.3;
    font-weight: 600;
}

@media (min-width: 640px) {
    .niriv-heading-responsive {
        font-size: var(--text-2xl);
    }
}

@media (min-width: 768px) {
    .niriv-heading-responsive {
        font-size: var(--text-3xl);
    }
}

@media (min-width: 1024px) {
    .niriv-heading-responsive {
        font-size: var(--text-4xl);
    }
}

/* ===== MOBILE-FIRST SEARCH FORM ===== */
.niriv-search-container {
    width: 100%;
    max-width: 100%;
    margin: 0 auto;
    padding: 0 var(--space-md);
}

@media (min-width: 640px) {
    .niriv-search-container {
        max-width: 570px;
        padding: 0 var(--space-sm);
    }
}

.niriv-search-input {
    width: 100%;
    padding: var(--space-md) var(--space-lg);
    font-size: var(--text-base);
    border-radius: var(--radius-xl);
    border: none;
    background: white;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-normal);
    min-height: var(--touch-comfortable);
}

.niriv-search-input:focus {
    outline: none;
    box-shadow: var(--shadow-lg);
    transform: translateY(-1px);
}

/* ===== MOBILE-FIRST NAVIGATION ===== */
.niriv-nav {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(229, 231, 235, 0.8);
    padding: var(--space-sm) 0;
}

.niriv-nav-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 var(--space-md);
}

.niriv-nav-menu {
    display: none; /* Hidden on mobile */
}

@media (min-width: 768px) {
    .niriv-nav-menu {
        display: flex;
        gap: var(--space-lg);
    }
}

.niriv-nav-toggle {
    display: block;
    background: none;
    border: none;
    padding: var(--space-sm);
    min-width: var(--touch-min);
    min-height: var(--touch-min);
}

@media (min-width: 768px) {
    .niriv-nav-toggle {
        display: none;
    }
}

/* ===== MOBILE-FIRST CARDS ===== */
.niriv-card {
    background: white;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    padding: var(--space-md);
    transition: all var(--transition-normal);
}

.niriv-card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

@media (min-width: 768px) {
    .niriv-card {
        padding: var(--space-lg);
    }
}

/* ===== MOBILE-FIRST BUTTONS ===== */
.niriv-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-sm) var(--space-md);
    font-size: var(--text-sm);
    font-weight: 500;
    border-radius: var(--radius-md);
    border: none;
    cursor: pointer;
    transition: all var(--transition-fast);
    min-height: var(--touch-min);
    min-width: var(--touch-min);
    text-decoration: none;
}

@media (min-width: 640px) {
    .niriv-btn {
        padding: var(--space-md) var(--space-lg);
        font-size: var(--text-base);
    }
}

.niriv-btn-primary {
    background: #1847ea;
    color: white;
}

.niriv-btn-primary:hover {
    background: #1538d1;
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

/* ===== MOBILE-FIRST SPACING UTILITIES ===== */
.niriv-space-y > * + * {
    margin-top: var(--space-md);
}

@media (min-width: 768px) {
    .niriv-space-y > * + * {
        margin-top: var(--space-lg);
    }
}

.niriv-space-x > * + * {
    margin-left: var(--space-md);
}

@media (min-width: 768px) {
    .niriv-space-x > * + * {
        margin-left: var(--space-lg);
    }
}

/* ===== MOBILE-FIRST VISIBILITY UTILITIES ===== */
.niriv-hidden-mobile {
    display: none;
}

@media (min-width: 640px) {
    .niriv-hidden-mobile {
        display: block;
    }
}

.niriv-hidden-desktop {
    display: block;
}

@media (min-width: 640px) {
    .niriv-hidden-desktop {
        display: none;
    }
}

/* ===== MOBILE-FIRST MASONRY LAYOUT ===== */
.niriv-masonry {
    column-count: 1;
    column-gap: var(--space-md);
    column-fill: balance;
}

.niriv-masonry > * {
    break-inside: avoid;
    margin-bottom: var(--space-md);
}

@media (min-width: 640px) {
    .niriv-masonry {
        column-count: 2;
    }
}

@media (min-width: 1024px) {
    .niriv-masonry {
        column-count: 3;
        column-gap: var(--space-lg);
    }
    
    .niriv-masonry > * {
        margin-bottom: var(--space-lg);
    }
}

/* ===== MOBILE-FIRST ASPECT RATIOS ===== */
.niriv-aspect-square {
    aspect-ratio: 1 / 1;
}

.niriv-aspect-video {
    aspect-ratio: 16 / 9;
}

.niriv-aspect-photo {
    aspect-ratio: 4 / 3;
}

/* ===== MOBILE-FIRST ANIMATIONS ===== */
@media (prefers-reduced-motion: no-preference) {
    .niriv-animate-fade-in {
        animation: niriv-fade-in 0.5s ease-out;
    }
    
    .niriv-animate-slide-up {
        animation: niriv-slide-up 0.5s ease-out;
    }
}

@keyframes niriv-fade-in {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

@keyframes niriv-slide-up {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ===== MOBILE-FIRST ACCESSIBILITY ===== */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* Focus styles for keyboard navigation */
.niriv-btn:focus,
.niriv-search-input:focus,
.niriv-nav-toggle:focus {
    outline: 2px solid #1847ea;
    outline-offset: 2px;
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    .niriv-card {
        border: 1px solid #000;
    }
    
    .niriv-btn-primary {
        border: 2px solid #000;
    }
}

/* ===== MOBILE-FIRST PRINT STYLES ===== */
@media print {
    .niriv-nav,
    .niriv-nav-toggle,
    .niriv-btn {
        display: none !important;
    }
    
    .niriv-container {
        max-width: none !important;
        padding: 0 !important;
    }
    
    .niriv-card {
        box-shadow: none !important;
        border: 1px solid #ccc !important;
    }
}