/**
 * Mobile Responsive Utilities
 * Shared CSS optimization for consistent mobile UX across all Zynergy pages
 * 
 * Usage: Add this link to base.html or each template:
 * <link rel="stylesheet" href="{% static 'css/mobile-responsive.css' %}">
 * 
 * Principle: Mobile-first approach with progressive enhancement
 */

/* ============================================================================
   ROOT VARIABLES - Centralized Control
   ============================================================================ */

:root {
    /* TYPOGRAPHY SCALE */
    --font-family-main: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Arial, sans-serif;
    --font-family-mono: 'Courier New', monospace;
    
    --font-size-xs: 0.75rem;        /* 12px */
    --font-size-sm: 0.875rem;       /* 14px */
    --font-size-base: 1rem;         /* 16px */
    --font-size-lg: 1.125rem;       /* 18px */
    --font-size-xl: 1.25rem;        /* 20px */
    --font-size-2xl: 1.5rem;        /* 24px */
    --font-size-3xl: 1.875rem;      /* 30px */
    --font-size-4xl: 2.25rem;       /* 36px */
    
    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;
    --font-weight-extrabold: 800;
    
    /* SPACING SCALE - Mobile First */
    --spacing-0: 0;
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 12px;
    --spacing-lg: 16px;
    --spacing-xl: 20px;
    --spacing-2xl: 24px;
    --spacing-3xl: 32px;
    --spacing-4xl: 40px;
    --spacing-5xl: 48px;
    
    /* TOUCH TARGET */
    --touch-target-min: 48px;  /* Minimum 48px×48px for fingers */
    
    /* RESPONSIVE BREAKPOINTS */
    --bp-xs: 320px;             /* Small phones */
    --bp-sm: 480px;             /* Standard phones */
    --bp-md: 768px;             /* Tablets */
    --bp-lg: 1024px;            /* Large tablets/laptops */
    --bp-xl: 1440px;            /* Desktops */
    
    /* CONTAINER SIZES */
    --container-xs: 320px;
    --container-sm: 640px;
    --container-md: 768px;
    --container-lg: 1000px;
    --container-xl: 1200px;
    
    /* COLORS - Neutral base (adjust per design system) */
    --color-body-bg: #ffffff;
    --color-body-text: #1a202c;
    --color-border: #e2e8f0;
    --color-shadow: rgba(0, 0, 0, 0.08);
    
    /* BORDER RADIUS */
    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 16px;
    
    /* TRANSITIONS */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 300ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 500ms cubic-bezier(0.4, 0, 0.2, 1);
    
    /* SHADOWS */
    --shadow-sm: 0 1px 2px var(--color-shadow);
    --shadow-md: 0 4px 6px var(--color-shadow);
    --shadow-lg: 0 10px 15px var(--color-shadow);
    --shadow-xl: 0 20px 25px var(--color-shadow);
}

/* TABLET ADJUSTMENTS (768px+) */
@media (min-width: 768px) {
    :root {
        --spacing-lg: 24px;
        --spacing-xl: 32px;
        --spacing-2xl: 40px;
        --font-size-2xl: 1.875rem;
        --font-size-3xl: 2.25rem;
    }
}

/* DESKTOP ADJUSTMENTS (1024px+) */
@media (min-width: 1024px) {
    :root {
        --spacing-xl: 40px;
        --spacing-2xl: 48px;
        --font-size-4xl: 2.5rem;
    }
}

/* ============================================================================
   BASE RESPONSIVE STYLES
   ============================================================================ */

/* Ensure all elements use border-box sizing */
* {
    box-sizing: border-box;
}

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-family-main);
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-normal);
    line-height: 1.6;
    color: var(--color-body-text);
    background-color: var(--color-body-bg);
    margin: 0;
    padding: 0;
    overflow-x: hidden;
    -webkit-overflow-scrolling: touch;
    -webkit-user-select: none;
    -webkit-touch-callout: none;
}

/* ============================================================================
   RESPONSIVE UTILITIES - Mobile First
   ============================================================================ */

/* CONTAINER - Padding-based approach for mobile */
.container {
    width: 100%;
    padding-left: var(--spacing-lg);
    padding-right: var(--spacing-lg);
    margin-left: auto;
    margin-right: auto;
}

@media (min-width: 480px) {
    .container {
        max-width: var(--container-sm);
    }
}

@media (min-width: 768px) {
    .container {
        max-width: var(--container-md);
    }
}

@media (min-width: 1000px) {
    .container {
        max-width: var(--container-lg);
        padding-left: var(--spacing-xl);
        padding-right: var(--spacing-xl);
    }
}

@media (min-width: 1200px) {
    .container {
        max-width: var(--container-xl);
    }
}

/* PAGE PADDING */
.page-padding {
    padding: var(--spacing-lg);
}

@media (min-width: 768px) {
    .page-padding {
        padding: var(--spacing-xl);
    }
}

/* SAFE AREA PADDING (for notch-aware devices) */
.safe-area {
    padding-left: max(var(--spacing-lg), env(safe-area-inset-left));
    padding-right: max(var(--spacing-lg), env(safe-area-inset-right));
    padding-top: max(var(--spacing-lg), env(safe-area-inset-top));
    padding-bottom: max(var(--spacing-lg), env(safe-area-inset-bottom));
}

/* ============================================================================
   TYPOGRAPHY UTILITIES
   ============================================================================ */

h1, h2, h3, h4, h5, h6 {
    margin: 0;
    font-weight: var(--font-weight-bold);
    line-height: 1.2;
}

h1 {
    font-size: var(--font-size-2xl);
}

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

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

p {
    margin: 0;
    line-height: 1.6;
}

/* Heading utilities */
.h1, .h2, .h3, .h4, .h5, .h6 {
    font-weight: var(--font-weight-bold);
    margin: 0;
}

.h1 { font-size: var(--font-size-2xl); }
.h2 { font-size: var(--font-size-xl); }
.h3 { font-size: var(--font-size-lg); }
.h4 { font-size: var(--font-size-base); }

.text-sm { font-size: var(--font-size-sm); }
.text-lg { font-size: var(--font-size-lg); }
.text-xl { font-size: var(--font-size-xl); }

.text-bold { font-weight: var(--font-weight-bold); }
.text-semibold { font-weight: var(--font-weight-semibold); }
.text-medium { font-weight: var(--font-weight-medium); }

/* FORM INPUTS - Mobile Optimized */
input[type="text"],
input[type="email"],
input[type="password"],
input[type="url"],
input[type="number"],
textarea,
select {
    /* Prevent iOS auto-zoom on input focus */
    font-size: 16px !important;
    padding: var(--spacing-lg);
    border: 2px solid var(--color-border);
    border-radius: var(--radius-md);
    font-family: var(--font-family-main);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
    width: 100%;
}

input[type="text"]:focus,
input[type="email"]:focus,
input[type="password"]:focus,
input[type="url"]:focus,
input[type="number"]:focus,
textarea:focus,
select:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

textarea {
    resize: vertical;
    min-height: 100px;
}

/* ============================================================================
   BUTTON UTILITIES - Touch-Friendly
   ============================================================================ */

button,
.btn,
[role="button"] {
    display: inline-block;
    min-height: var(--touch-target-min);
    padding: var(--spacing-md) var(--spacing-lg);
    border: 2px solid transparent;
    border-radius: var(--radius-md);
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-bold);
    text-decoration: none;
    text-align: center;
    cursor: pointer;
    user-select: none;
    transition: all var(--transition-fast);
    -webkit-tap-highlight-color: transparent;
    -webkit-touch-callout: none;
}

/* Full-width buttons on mobile */
.btn-block,
.btn-full {
    width: 100%;
    display: block;
}

@media (min-width: 768px) {
    .btn-block,
    .btn-full {
        width: auto;
        display: inline-block;
    }
}

/* Button groups with flex wrapping */
.button-group {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-md);
    justify-content: center;
}

@media (min-width: 768px) {
    .button-group {
        gap: var(--spacing-lg);
    }
}

.button-group .btn {
    flex: 1;
    min-width: 120px;
}

@media (min-width: 480px) {
    .button-group .btn {
        flex: 0 1 auto;
    }
}

/* ============================================================================
   GRID UTILITIES - Responsive Layout
   ============================================================================ */

/* Responsive grid (1 column on mobile, auto on larger) */
.grid {
    display: grid;
    gap: var(--spacing-lg);
}

/* 2-column grid on tablet+ */
.grid-2 {
    display: grid;
    gap: var(--spacing-lg);
    grid-template-columns: 1fr;
}

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

/* 3-column grid on desktop+ */
.grid-3 {
    display: grid;
    gap: var(--spacing-lg);
    grid-template-columns: 1fr;
}

@media (min-width: 768px) {
    .grid-3 {
        grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    }
}

/* Modern auto-fill grid (like curriculum_generic.html) */
.grid-auto {
    display: grid;
    gap: var(--spacing-lg);
    grid-template-columns: 1fr;
}

@media (min-width: 480px) {
    .grid-auto {
        grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    }
}

/* ============================================================================
   FLEX UTILITIES
   ============================================================================ */

.flex {
    display: flex;
}

.flex-col {
    flex-direction: column;
}

.flex-wrap {
    flex-wrap: wrap;
}

.flex-center {
    justify-content: center;
    align-items: center;
}

.flex-between {
    justify-content: space-between;
    align-items: center;
}

.gap-sm { gap: var(--spacing-sm); }
.gap-md { gap: var(--spacing-md); }
.gap-lg { gap: var(--spacing-lg); }
.gap-xl { gap: var(--spacing-xl); }

/* Stack vertically on mobile, horizontally on tablet+ */
.flex-responsive {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

@media (min-width: 768px) {
    .flex-responsive {
        flex-direction: row;
        flex-wrap: wrap;
    }
}

/* ============================================================================
   CARD UTILITIES
   ============================================================================ */

.card {
    background: white;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-base);
}

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

@media (min-width: 768px) {
    .card {
        padding: var(--spacing-xl);
    }
}

.card-header {
    margin-bottom: var(--spacing-lg);
    padding-bottom: var(--spacing-lg);
    border-bottom: 2px solid var(--color-border);
}

.card-body {
    margin: var(--spacing-lg) 0;
}

.card-footer {
    margin-top: var(--spacing-lg);
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--color-border);
}

/* ============================================================================
   SPACING UTILITIES
   ============================================================================ */

.mt-0 { margin-top: var(--spacing-0); }
.mt-xs { margin-top: var(--spacing-xs); }
.mt-sm { margin-top: var(--spacing-sm); }
.mt-md { margin-top: var(--spacing-md); }
.mt-lg { margin-top: var(--spacing-lg); }
.mt-xl { margin-top: var(--spacing-xl); }
.mt-2xl { margin-top: var(--spacing-2xl); }

.mb-0 { margin-bottom: var(--spacing-0); }
.mb-xs { margin-bottom: var(--spacing-xs); }
.mb-sm { margin-bottom: var(--spacing-sm); }
.mb-md { margin-bottom: var(--spacing-md); }
.mb-lg { margin-bottom: var(--spacing-lg); }
.mb-xl { margin-bottom: var(--spacing-xl); }
.mb-2xl { margin-bottom: var(--spacing-2xl); }

.p-0 { padding: var(--spacing-0); }
.p-xs { padding: var(--spacing-xs); }
.p-sm { padding: var(--spacing-sm); }
.p-md { padding: var(--spacing-md); }
.p-lg { padding: var(--spacing-lg); }
.p-xl { padding: var(--spacing-xl); }

.px-lg { padding-left: var(--spacing-lg); padding-right: var(--spacing-lg); }
.py-lg { padding-top: var(--spacing-lg); padding-bottom: var(--spacing-lg); }

/* ============================================================================
   VISIBILITY & DISPLAY
   ============================================================================ */

/* Hide on mobile, show on tablet+ */
.hide-mobile {
    display: none !important;
}

@media (min-width: 768px) {
    .hide-mobile {
        display: block !important;
    }
}

/* Show on mobile, hide on tablet+ */
.show-mobile {
    display: block !important;
}

@media (min-width: 768px) {
    .show-mobile {
        display: none !important;
    }
}

/* ============================================================================
   BACK BUTTON / NAVIGATION
   ============================================================================ */

.back-btn,
.back-button {
    display: inline-block;
    min-height: var(--touch-target-min);
    padding: var(--spacing-md) var(--spacing-lg);
    color: #667eea;
    background: rgba(255, 255, 255, 0.85);
    border: 2px solid transparent;
    border-radius: var(--radius-md);
    text-decoration: none;
    font-weight: var(--font-weight-bold);
    cursor: pointer;
    transition: all var(--transition-fast);
    box-shadow: var(--shadow-sm);
    margin-bottom: var(--spacing-xl);
}

.back-btn:hover,
.back-button:hover {
    background: rgba(255, 255, 255, 0.95);
    color: #764ba2;
    transform: translateX(-4px);
    box-shadow: var(--shadow-md);
}

/* ============================================================================
   FORMS
   ============================================================================ */

.form-group {
    margin-bottom: var(--spacing-xl);
}

.form-group label {
    display: block;
    font-weight: var(--font-weight-bold);
    margin-bottom: var(--spacing-md);
    font-size: var(--font-size-base);
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
}

.form-section {
    margin-bottom: var(--spacing-2xl);
}

@media (min-width: 768px) {
    .form-section {
        margin-bottom: var(--spacing-3xl);
    }
}

.form-section h3 {
    font-size: var(--font-size-lg);
    margin-bottom: var(--spacing-xl);
    padding-bottom: var(--spacing-lg);
    border-bottom: 2px solid var(--color-border);
}

.error-message {
    color: #e53e3e;
    font-size: var(--font-size-sm);
    margin-top: var(--spacing-md);
    padding: var(--spacing-md);
    background: rgba(229, 62, 62, 0.1);
    border-radius: var(--radius-md);
}

.help-text {
    display: block;
    color: #718096;
    font-size: var(--font-size-sm);
    margin-top: var(--spacing-md);
}

/* ============================================================================
   RESPONSIVE TEXT UTILITIES
   ============================================================================ */

.text-center {
    text-align: center;
}

.text-left {
    text-align: left;
}

.text-right {
    text-align: right;
}

@media (max-width: 480px) {
    .text-center-mobile {
        text-align: center;
    }
}

/* ============================================================================
   OVERFLOW & TEXT HANDLING
   ============================================================================ */

.text-truncate {
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.text-break {
    word-break: break-word;
    overflow-wrap: break-word;
}

.no-scroll {
    overflow: hidden;
}

/* ============================================================================
   PERFORMANCE OPTIMIZATIONS
   ============================================================================ */

/* Reduce motion on mobile devices that support it */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}

/* Disable expensive visual effects on low-end devices */
@media (max-width: 480px) {
    /* Remove backdrop-filter on very small screens */
    .blur-effect {
        backdrop-filter: none;
    }
    
    /* Simplify shadows */
    .card {
        box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    }
}

/* ============================================================================
   PRINT STYLES
   ============================================================================ */

@media print {
    body {
        background: white;
    }
    
    .hide-print {
        display: none !important;
    }
    
    .card {
        box-shadow: none;
        border: 1px solid #ccc;
    }
}