/* $TAP Mini App - Main Styles with Enhanced Responsive Design */

:root {
    /* Colors */
    --primary-bg: #0F0F23;
    --secondary-bg: #1A1A2E;
    --card-bg: #16213E;
    --accent-blue: #0F3460;
    --accent-red: #E94560;
    --accent-orange: #F39C12;
    --text-primary: #FFFFFF;
    --text-secondary: #B0B3B8;
    --text-muted: #65676B;
    --border-color: rgba(255, 255, 255, 0.1);
    --gradient-primary: linear-gradient(135deg, #E94560 0%, #F39C12 100%);
    --gradient-secondary: linear-gradient(135deg, #0F3460 0%, #16213E 100%);
    
    /* Responsive Spacing - Base (Mobile) */
    --padding-xs: 4px;
    --padding-sm: 8px;
    --padding-md: 12px;
    --padding-lg: 16px;
    --padding-xl: 24px;
    
    /* Responsive Border radius */
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 14px;
    --radius-xl: 20px;
    
    /* Responsive Typography - Base (Mobile) */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-size-xs: 11px;
    --font-size-sm: 13px;
    --font-size-md: 15px;
    --font-size-lg: 17px;
    --font-size-xl: 21px;
    --font-size-2xl: 28px;
    
    /* Shadows */
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.2);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.3);
    
    /* Transitions */
    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
    
    /* Responsive Container Widths */
    --container-xs: 100%;
    --container-sm: 100%;
    --container-md: 768px;
    --container-lg: 1024px;
    --container-xl: 1200px;
}

/* Enhanced Responsive Breakpoints */
@media (min-width: 375px) {
    :root {
        --padding-md: 14px;
        --padding-lg: 18px;
        --padding-xl: 26px;
        --font-size-md: 16px;
        --font-size-lg: 18px;
        --font-size-xl: 22px;
        --font-size-2xl: 30px;
    }
}

@media (min-width: 414px) {
    :root {
        --padding-md: 16px;
        --padding-lg: 20px;
        --padding-xl: 28px;
        --radius-md: 12px;
        --radius-lg: 16px;
        --radius-xl: 22px;
    }
}

@media (min-width: 768px) {
    :root {
        --padding-md: 18px;
        --padding-lg: 24px;
        --padding-xl: 32px;
        --font-size-md: 17px;
        --font-size-lg: 19px;
        --font-size-xl: 25px;
        --font-size-2xl: 34px;
        --radius-md: 14px;
        --radius-lg: 18px;
        --radius-xl: 26px;
    }
}

@media (min-width: 1024px) {
    :root {
        --padding-md: 20px;
        --padding-lg: 28px;
        --padding-xl: 36px;
        --font-size-md: 18px;
        --font-size-lg: 20px;
        --font-size-xl: 26px;
        --font-size-2xl: 36px;
    }
}

/* Reset and Base */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: var(--font-family);
    background: var(--primary-bg);
    color: var(--text-primary);
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    user-select: none;
    -webkit-user-select: none;
    -webkit-tap-highlight-color: transparent;
    
    /* Enhanced Mobile Optimizations */
    touch-action: manipulation;
    -webkit-overflow-scrolling: touch;
    -webkit-text-size-adjust: 100%;
    -ms-text-size-adjust: 100%;
    
    /* Fix for iOS safe areas */
    padding-top: env(safe-area-inset-top);
    padding-bottom: env(safe-area-inset-bottom);
    padding-left: env(safe-area-inset-left);
    padding-right: env(safe-area-inset-right);
}

/* Loading Screen */
.loading-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background: var(--primary-bg);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
    animation: fadeIn 0.3s ease;
}

.loading-content {
    text-align: center;
    animation: slideUp 0.5s ease;
}

.tap-logo {
    width: 80px;
    height: 80px;
    margin: 0 auto var(--padding-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--gradient-primary);
    border-radius: var(--radius-xl);
    font-size: 36px;
    color: white;
    animation: pulse 2s infinite;
}

.loading-content h1 {
    font-size: var(--font-size-2xl);
    font-weight: 800;
    margin-bottom: var(--padding-lg);
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.loading-spinner {
    width: 32px;
    height: 32px;
    border: 3px solid var(--border-color);
    border-top: 3px solid var(--accent-red);
    border-radius: 50%;
    margin: var(--padding-lg) auto;
    animation: spin 1s linear infinite;
}

.loading-content p {
    color: var(--text-secondary);
    font-size: var(--font-size-sm);
}

/* App Container */
.app {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    padding-bottom: 80px; /* Space for navigation */
}

.app.hidden {
    display: none;
}

/* Header - Mobile First Design */
.app-header {
    background: var(--secondary-bg);
    padding: var(--padding-md) var(--padding-lg);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 100;
    
    /* Mobile optimizations */
    min-height: 60px;
    display: flex;
    align-items: center;
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: 100%;
    max-width: 420px;
    margin: 0 auto;
}

/* Mobile-first responsive header adjustments */
@media (max-width: 374px) {
    .app-header {
        padding: var(--padding-sm) var(--padding-md);
        min-height: 56px;
    }
}

@media (min-width: 375px) and (max-width: 413px) {
    .app-header {
        padding: var(--padding-md);
        min-height: 58px;
    }
}

@media (min-width: 414px) {
    .app-header {
        padding: var(--padding-md) var(--padding-lg);
        min-height: 62px;
    }
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--padding-sm);
    font-size: var(--font-size-lg);
    font-weight: 700;
}

.logo i {
    color: var(--accent-red);
}

.user-info {
    display: flex;
    align-items: center;
    gap: var(--padding-sm);
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
}

.user-avatar {
    width: 32px;
    height: 32px;
    background: var(--gradient-secondary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--font-size-sm);
}

/* Balance Section - Mobile Optimized */
.balance-section {
    padding: var(--padding-lg) var(--padding-md);
    text-align: center;
    
    /* Mobile-first optimizations */
    position: relative;
    background: linear-gradient(135deg, rgba(15, 15, 35, 0.8) 0%, rgba(26, 26, 46, 0.8) 100%);
    backdrop-filter: blur(10px);
}

.balance-card {
    background: var(--gradient-secondary);
    border-radius: var(--radius-lg);
    padding: var(--padding-xl);
    box-shadow: var(--shadow-md);
    
    /* Enhanced mobile touch experience */
    touch-action: manipulation;
    transition: transform 0.2s ease;
    max-width: 360px;
    margin: 0 auto;
}

.balance-card:active {
    transform: scale(0.98);
}

.balance-amount {
    font-size: clamp(28px, 8vw, 48px); /* Responsive font size */
    font-weight: 800;
    line-height: 1;
    margin-bottom: var(--padding-sm);
    
    /* Better text rendering on mobile */
    -webkit-font-smoothing: antialiased;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
}

/* Device-specific balance optimizations */
@media (max-width: 374px) {
    .balance-section {
        padding: var(--padding-md);
    }
    
    .balance-card {
        padding: var(--padding-lg);
    }
    
    .balance-amount {
        font-size: 32px;
    }
}

@media (min-width: 375px) and (max-width: 413px) {
    .balance-amount {
        font-size: 40px;
    }
}

@media (min-width: 414px) {
    .balance-amount {
        font-size: 48px;
    }
}

.balance-unit {
    font-size: var(--font-size-lg);
    color: var(--text-secondary);
    font-weight: 500;
}

.balance-subtext {
    color: var(--text-secondary);
    font-size: var(--font-size-sm);
}

/* Progress Section */
.progress-section {
    padding: 0 var(--padding-md) var(--padding-lg);
}

.progress-text {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--padding-sm);
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
}

.progress-bar {
    height: 8px;
    background: var(--secondary-bg);
    border-radius: var(--radius-sm);
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: var(--gradient-primary);
    border-radius: var(--radius-sm);
    transition: width var(--transition-normal);
}

/* Main Content */
.main-content {
    flex: 1;
    position: relative;
    overflow: hidden;
}

.screen {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    padding: var(--padding-md);
    opacity: 0;
    visibility: hidden;
    transform: translateX(100%);
    transition: all var(--transition-normal);
}

.screen.active {
    opacity: 1;
    visibility: visible;
    transform: translateX(0);
}

.screen-header {
    text-align: center;
    margin-bottom: var(--padding-xl);
}

.screen-header h2 {
    font-size: var(--font-size-xl);
    font-weight: 700;
    margin-bottom: var(--padding-sm);
}

.screen-header p {
    color: var(--text-secondary);
    font-size: var(--font-size-sm);
}

/* Tap Game */
.tap-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--padding-xl);
    padding: var(--padding-xl) 0;
}

.tap-area {
    position: relative;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--padding-lg);
}

.tap-button {
    width: clamp(180px, 45vw, 220px);  /* Responsive size */
    height: clamp(180px, 45vw, 220px);
    background: var(--gradient-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    user-select: none;
    position: relative;
    overflow: hidden;
    box-shadow: var(--shadow-lg);
    transition: all var(--transition-fast);
    
    /* Enhanced mobile optimizations */
    touch-action: manipulation;
    -webkit-tap-highlight-color: transparent;
    -webkit-touch-callout: none;
    -webkit-user-drag: none;
    
    /* Better touch feedback */
    will-change: transform;
    backface-visibility: hidden;
    
    /* Ensure minimum touch target size (44px) */
    min-width: 44px;
    min-height: 44px;
}

.tap-button:hover {
    transform: scale(1.05);
}

.tap-button:active {
    transform: scale(0.92);
    box-shadow: var(--shadow-md);
}

.tap-button.tapped {
    animation: tapPulse 0.3s ease-out;
}

@keyframes tapPulse {
    0% { transform: scale(1); }
    50% { transform: scale(0.95); }
    100% { transform: scale(1); }
}

.tap-button.disabled {
    background: var(--secondary-bg);
    cursor: not-allowed;
    opacity: 0.6;
    pointer-events: none;
}

.tap-icon {
    font-size: clamp(48px, 12vw, 64px);  /* Responsive icon size */
    color: white;
    z-index: 2;
    
    /* Better icon rendering on mobile */
    -webkit-font-smoothing: antialiased;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
}

/* Device-specific tap button optimizations */
@media (max-width: 374px) {
    .tap-button {
        width: 160px;
        height: 160px;
    }
    
    .tap-icon {
        font-size: 44px;
    }
}

@media (min-width: 375px) and (max-width: 413px) {
    .tap-button {
        width: 180px;
        height: 180px;
    }
    
    .tap-icon {
        font-size: 52px;
    }
}

@media (min-width: 414px) {
    .tap-button {
        width: 200px;
        height: 200px;
    }
    
    .tap-icon {
        font-size: 60px;
    }
}

/* Landscape mode optimizations */
@media (orientation: landscape) and (max-height: 500px) {
    .tap-button {
        width: 140px;
        height: 140px;
    }
    
    .tap-icon {
        font-size: 40px;
    }
}

.tap-counter {
    position: absolute;
    top: -40px;
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--accent-orange);
    opacity: 0;
    animation: floatUp 1s ease-out;
}

.tap-timer {
    width: 100%;
    max-width: 300px;
    text-align: center;
}

.timer-text {
    margin-bottom: var(--padding-sm);
    font-size: var(--font-size-lg);
    font-weight: 600;
}

.timer-bar {
    height: 12px;
    background: var(--secondary-bg);
    border-radius: var(--radius-sm);
    overflow: hidden;
}

.timer-fill {
    height: 100%;
    background: var(--gradient-primary);
    border-radius: var(--radius-sm);
    transition: width var(--transition-fast);
}

.tap-instructions {
    text-align: center;
    color: var(--text-secondary);
}

.tap-instructions p {
    margin-bottom: var(--padding-xs);
}

.tap-instructions .small {
    font-size: var(--font-size-xs);
    color: var(--text-muted);
}

/* Tap Results */
.tap-results {
    text-align: center;
    padding: var(--padding-xl);
    background: var(--secondary-bg);
    border-radius: var(--radius-lg);
    margin: var(--padding-lg) 0;
}

.tap-results.hidden {
    display: none;
}

.results-icon {
    font-size: 48px;
    margin-bottom: var(--padding-md);
}

.tap-results h3 {
    font-size: var(--font-size-xl);
    margin-bottom: var(--padding-md);
}

.total-text {
    color: var(--text-secondary);
    margin-bottom: var(--padding-sm);
}

.exchange-hint {
    color: var(--text-muted);
    font-size: var(--font-size-sm);
    margin-bottom: var(--padding-lg);
}

.next-actions h4 {
    margin-bottom: var(--padding-md);
    color: var(--text-secondary);
}

.action-buttons {
    display: flex;
    flex-direction: column;
    gap: var(--padding-sm);
}

/* Buttons */
.btn {
    background: var(--gradient-primary);
    color: white;
    border: none;
    border-radius: var(--radius-md);
    padding: var(--padding-md) var(--padding-lg);
    font-size: var(--font-size-md);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--padding-sm);
}

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

.btn:active {
    transform: translateY(0);
}

.btn.secondary {
    background: var(--secondary-bg);
    border: 1px solid var(--border-color);
}

.btn.secondary:hover {
    border-color: var(--accent-red);
}

/* Action buttons for staking */
.action-btn {
    background: var(--gradient-primary);
    color: white;
    border: none;
    border-radius: var(--radius-md);
    padding: var(--padding-md) var(--padding-lg);
    font-size: var(--font-size-md);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--padding-sm);
    margin-bottom: var(--padding-sm);
}

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

.action-btn:active {
    transform: translateY(0);
}

.action-btn.secondary {
    background: var(--secondary-bg);
    border: 1px solid var(--border-color);
}

.action-btn.secondary:hover {
    border-color: var(--accent-blue);
    background: var(--accent-blue);
}

.action-btn.accent {
    background: linear-gradient(135deg, var(--accent-orange) 0%, var(--accent-red) 100%);
}

.action-btn.accent:hover {
    box-shadow: 0 8px 25px rgba(243, 156, 18, 0.4);
}

.action-btn.warning {
    background: linear-gradient(135deg, #e74c3c 0%, #c0392b 100%);
    color: white;
}

.action-btn.warning:hover {
    box-shadow: 0 8px 25px rgba(231, 76, 60, 0.4);
    background: linear-gradient(135deg, #c0392b 0%, #a93226 100%);
}

.action-btn.warning:active {
    background: linear-gradient(135deg, #a93226 0%, #922b21 100%);
}

/* Buy Screen */
.stage-info {
    margin-bottom: var(--padding-xl);
}

.stage-card {
    background: var(--secondary-bg);
    border-radius: var(--radius-lg);
    padding: var(--padding-lg);
    border: 1px solid var(--border-color);
}

.stage-title {
    font-size: var(--font-size-lg);
    font-weight: 700;
    color: var(--accent-orange);
    margin-bottom: var(--padding-sm);
}

.stage-price {
    font-size: var(--font-size-xl);
    font-weight: 800;
    margin-bottom: var(--padding-sm);
}

.stage-next {
    color: var(--text-secondary);
    font-size: var(--font-size-sm);
    margin-bottom: var(--padding-md);
}

.stage-progress {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--padding-md);
}

.stage-progress .progress-bar {
    flex: 1;
}

.stage-progress span {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
}

.buy-amounts {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--padding-md);
    margin-bottom: var(--padding-xl);
}

.buy-btn {
    background: var(--secondary-bg);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: var(--padding-lg);
    text-align: left;
    cursor: pointer;
    transition: all var(--transition-fast);
    position: relative;
    overflow: hidden;
}

.buy-btn:hover {
    border-color: var(--accent-red);
    transform: translateY(-2px);
}

.buy-btn.featured {
    border-color: var(--accent-orange);
    background: linear-gradient(135deg, var(--secondary-bg) 0%, rgba(243, 156, 18, 0.1) 100%);
}

.buy-btn .amount {
    display: block;
    font-size: var(--font-size-lg);
    font-weight: 700;
    margin-bottom: var(--padding-xs);
}

.buy-btn .price {
    display: block;
    color: var(--text-secondary);
    font-size: var(--font-size-sm);
}

.buy-btn .badge {
    position: absolute;
    top: var(--padding-sm);
    right: var(--padding-sm);
    background: var(--accent-orange);
    color: white;
    padding: var(--padding-xs) var(--padding-sm);
    border-radius: var(--radius-sm);
    font-size: var(--font-size-xs);
    font-weight: 600;
}

.custom-amount {
    background: var(--secondary-bg);
    border-radius: var(--radius-lg);
    padding: var(--padding-lg);
    margin-bottom: var(--padding-xl);
}

.custom-amount input {
    width: 100%;
    background: transparent;
    border: none;
    color: var(--text-primary);
    font-size: var(--font-size-md);
    margin-bottom: var(--padding-sm);
    outline: none;
}

.custom-amount input::placeholder {
    color: var(--text-muted);
}

.custom-price {
    color: var(--text-secondary);
    font-size: var(--font-size-sm);
}

.connect-wallet-btn {
    width: 100%;
    background: var(--gradient-primary);
    color: white;
    border: none;
    border-radius: var(--radius-lg);
    padding: var(--padding-lg);
    font-size: var(--font-size-lg);
    font-weight: 700;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--padding-sm);
    transition: all var(--transition-fast);
}

.connect-wallet-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

/* Invite Screen */
.invite-card {
    background: var(--secondary-bg);
    border-radius: var(--radius-lg);
    padding: var(--padding-xl);
    margin-bottom: var(--padding-xl);
}

.invite-reward {
    display: flex;
    align-items: center;
    gap: var(--padding-lg);
    margin-bottom: var(--padding-xl);
}

.reward-icon {
    font-size: 48px;
}

.reward-text {
    flex: 1;
}

.reward-amount {
    display: block;
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--accent-orange);
}

.reward-desc {
    display: block;
    color: var(--text-secondary);
    font-size: var(--font-size-sm);
}

.invite-link-section {
    text-align: center;
}

.invite-link {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: var(--padding-md);
    font-family: monospace;
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    margin-bottom: var(--padding-md);
    word-break: break-all;
}

.invite-buttons {
    display: flex;
    gap: var(--padding-sm);
}

.invite-buttons .btn {
    flex: 1;
}

/* Navigation - Mobile Optimized */
.bottom-nav {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: var(--secondary-bg);
    border-top: 1px solid var(--border-color);
    display: flex;
    z-index: 1000;
    
    /* Enhanced mobile optimizations */
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    
    /* Safe area support for devices with home indicator */
    padding-bottom: env(safe-area-inset-bottom);
    
    /* Minimum height for touch targets */
    min-height: 64px;
    
    /* Prevent scrolling issues */
    overscroll-behavior: none;
    -webkit-overflow-scrolling: touch;
}

.nav-item {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: var(--padding-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
    color: var(--text-muted);
    font-size: var(--font-size-xs);
    
    /* Enhanced touch experience */
    touch-action: manipulation;
    -webkit-tap-highlight-color: transparent;
    min-height: 44px;  /* Minimum touch target */
    position: relative;
    
    /* Better text rendering */
    -webkit-font-smoothing: antialiased;
}

.nav-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: transparent;
    transition: background-color var(--transition-fast);
}

.nav-item:active::before {
    background: rgba(255, 255, 255, 0.1);
}

.nav-item i {
    font-size: clamp(16px, 4vw, 20px);  /* Responsive icon size */
    margin-bottom: var(--padding-xs);
    position: relative;
    z-index: 1;
}

.nav-item span {
    font-size: clamp(10px, 2.5vw, 12px);  /* Responsive text size */
    font-weight: 500;
    position: relative;
    z-index: 1;
}

.nav-item.active {
    color: var(--accent-red);
    transform: translateY(-1px);
}

.nav-item.active::before {
    background: rgba(233, 69, 96, 0.1);
}

.nav-item:hover:not(.active) {
    color: var(--text-secondary);
}

/* Device-specific navigation optimizations */
@media (max-width: 374px) {
    .bottom-nav {
        min-height: 60px;
    }
    
    .nav-item {
        padding: 6px 4px;
    }
    
    .nav-item i {
        font-size: 16px;
        margin-bottom: 2px;
    }
    
    .nav-item span {
        font-size: 9px;
    }
}

@media (min-width: 375px) and (max-width: 413px) {
    .bottom-nav {
        min-height: 62px;
    }
    
    .nav-item i {
        font-size: 18px;
    }
    
    .nav-item span {
        font-size: 10px;
    }
}

@media (min-width: 414px) {
    .bottom-nav {
        min-height: 64px;
    }
    
    .nav-item i {
        font-size: 20px;
    }
    
    .nav-item span {
        font-size: 11px;
    }
}

/* Landscape mode navigation adjustments */
@media (orientation: landscape) and (max-height: 500px) {
    .bottom-nav {
        min-height: 48px;
    }
    
    .nav-item {
        padding: 4px 2px;
    }
    
    .nav-item i {
        font-size: 14px;
        margin-bottom: 1px;
    }
    
    .nav-item span {
        font-size: 8px;
    }
}

/* Toast */
.toast-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background: rgba(0, 0, 0, 0.8);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 10000;
    animation: fadeIn var(--transition-normal);
}

.toast-overlay.hidden {
    display: none;
}

.toast-content {
    background: var(--secondary-bg);
    border-radius: var(--radius-lg);
    padding: var(--padding-xl);
    text-align: center;
    max-width: 300px;
    margin: var(--padding-md);
    animation: slideUp var(--transition-normal);
}

.toast-icon {
    font-size: 48px;
    margin-bottom: var(--padding-md);
}

.toast-content h3 {
    font-size: var(--font-size-xl);
    margin-bottom: var(--padding-md);
}

.toast-content p {
    color: var(--text-secondary);
    margin-bottom: var(--padding-sm);
}

.balance-text {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--accent-orange);
}

/* Utility Classes */
.hidden {
    display: none !important;
}

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

.text-primary {
    color: var(--text-primary);
}

.text-secondary {
    color: var(--text-secondary);
}

.text-muted {
    color: var(--text-muted);
}

.mb-sm { margin-bottom: var(--padding-sm); }
.mb-md { margin-bottom: var(--padding-md); }
.mb-lg { margin-bottom: var(--padding-lg); }
.mb-xl { margin-bottom: var(--padding-xl); }

.mt-sm { margin-top: var(--padding-sm); }
.mt-md { margin-top: var(--padding-md); }
.mt-lg { margin-top: var(--padding-lg); }
.mt-xl { margin-top: var(--padding-xl); }

/* Responsive Design */
@media (min-width: 480px) {
    .buy-amounts {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .invite-buttons {
        justify-content: center;
    }
    
    .invite-buttons .btn {
        flex: 0 0 auto;
        min-width: 120px;
    }
}

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

/* High DPI displays */
@media (-webkit-min-device-pixel-ratio: 2), (min-resolution: 192dpi) {
    .tap-button {
        box-shadow: var(--shadow-lg), inset 0 1px 0 rgba(255, 255, 255, 0.1);
    }
}

/* Dark mode support */
@media (prefers-color-scheme: dark) {
    /* Already using dark theme as default */
}

/* Enhanced Comprehensive Responsive Design */

/* Small Mobile Devices (320px - 374px) */
@media (max-width: 374px) {
    .app-header {
        padding: var(--padding-sm) var(--padding-md);
    }
    
    .balance-section .balance-card {
        padding: var(--padding-md);
        margin: var(--padding-sm) var(--padding-md);
    }
    
    .balance-amount {
        font-size: 1.8rem;
    }
    
    .tap-button {
        width: 120px;
        height: 120px;
    }
    
    .tap-icon {
        font-size: 48px;
    }
    
    .buy-options-enhanced .popular-amounts {
        grid-template-columns: 1fr;
        gap: var(--padding-sm);
    }
    
    .nav-item-opt {
        min-width: 60px;
    }
    
    .nav-label {
        font-size: 10px;
    }
}

/* Standard Mobile Devices (375px - 413px) */
@media (min-width: 375px) and (max-width: 413px) {
    .balance-amount {
        font-size: 2.2rem;
    }
    
    .tap-button {
        width: 140px;
        height: 140px;
    }
    
    .tap-icon {
        font-size: 56px;
    }
    
    .buy-options-enhanced .popular-amounts {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--padding-md);
    }
}

/* Large Mobile Devices (414px - 767px) */
@media (min-width: 414px) and (max-width: 767px) {
    .balance-amount {
        font-size: 2.5rem;
    }
    
    .tap-button {
        width: 160px;
        height: 160px;
    }
    
    .tap-icon {
        font-size: 64px;
    }
    
    .buy-options-enhanced .popular-amounts {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--padding-lg);
    }
    
    .shop-products.enhanced {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* Tablet Portrait (768px - 1023px) */
@media (min-width: 768px) and (max-width: 1023px) {
    .app {
        max-width: 600px;
        margin: 0 auto;
        background: var(--secondary-bg);
        min-height: 100vh;
    }
    
    .balance-amount {
        font-size: 3rem;
    }
    
    .tap-button {
        width: 200px;
        height: 200px;
    }
    
    .tap-icon {
        font-size: 80px;
    }
    
    .buy-options-enhanced .popular-amounts {
        grid-template-columns: repeat(3, 1fr);
        gap: var(--padding-lg);
    }
    
    .shop-products.enhanced {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .bottom-nav-optimized {
        max-width: 600px;
        margin: 0 auto;
        left: 50%;
        transform: translateX(-50%);
    }
}

/* Desktop and Large Tablets (1024px+) */
@media (min-width: 1024px) {
    .app {
        max-width: 400px;
        margin: 0 auto;
        background: var(--secondary-bg);
        min-height: 100vh;
        box-shadow: var(--shadow-lg);
    }
    
    .balance-amount {
        font-size: 2.8rem;
    }
    
    .tap-button {
        width: 180px;
        height: 180px;
    }
    
    .tap-icon {
        font-size: 72px;
    }
    
    .buy-options-enhanced .popular-amounts {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--padding-lg);
    }
    
    .shop-products.enhanced {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .bottom-nav-optimized {
        max-width: 400px;
        margin: 0 auto;
        left: 50%;
        transform: translateX(-50%);
    }
}

/* Ultra-wide Screens (1440px+) */
@media (min-width: 1440px) {
    .app {
        max-width: 420px;
    }
    
    .bottom-nav-optimized {
        max-width: 420px;
    }
}

/* Landscape Mobile Devices */
@media (orientation: landscape) and (max-height: 500px) {
    .app-header {
        padding: var(--padding-xs) var(--padding-md);
    }
    
    .balance-section {
        margin: var(--padding-sm) 0;
    }
    
    .balance-card {
        padding: var(--padding-sm) var(--padding-md);
    }
    
    .tap-button {
        width: 100px;
        height: 100px;
    }
    
    .tap-icon {
        font-size: 40px;
    }
    
    .progress-section {
        margin: var(--padding-xs) var(--padding-md);
    }
    
    .apr-highlight-banner {
        padding: var(--padding-sm);
        margin: var(--padding-xs) var(--padding-md);
    }
}

/* Touch Device Optimizations */
@media (pointer: coarse) {
    .tap-button {
        touch-action: manipulation;
    }
    
    .btn, .nav-item-opt, .buy-btn-enhanced {
        min-height: 44px; /* Minimum touch target size */
        touch-action: manipulation;
    }
    
    .nav-item-opt {
        padding: var(--padding-sm);
    }
}

/* High DPI Display Optimizations */
@media (-webkit-min-device-pixel-ratio: 2), (min-resolution: 192dpi) {
    .tap-button {
        box-shadow: var(--shadow-lg), inset 0 1px 0 rgba(255, 255, 255, 0.1);
    }
    
    .btn, .buy-btn-enhanced {
        box-shadow: var(--shadow-md), inset 0 1px 0 rgba(255, 255, 255, 0.1);
    }
}

/* Admin Panel Responsive Design */
@media (min-width: 768px) {
    .admin-section {
        padding: var(--padding-xl);
    }
    
    .more-options-grid {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .package-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

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

/* Performance Optimizations */
@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;
    }
}

/* Print Styles */
@media print {
    .app {
        background: white;
        color: black;
        box-shadow: none;
    }
    
    .bottom-nav-optimized,
    .tap-button,
    .btn {
        display: none;
    }
}

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