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

:root {
    /* Color Palette - Light Mode */
    --primary-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --secondary-gradient: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --success-gradient: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    --warning-gradient: linear-gradient(135deg, #fa709a 0%, #fee140 100%);
    --danger-gradient: linear-gradient(135deg, #ff6b6b 0%, #ee5a52 100%);
    --accent-gradient: linear-gradient(135deg, #a8edea 0%, #fed6e3 100%);
    
    /* Theme Colors - Light Mode */
    --bg-primary: linear-gradient(135deg, #fefefe 0%, #f8fafc 100%);
    --bg-secondary: #f8fafc;
    --bg-tertiary: #f1f5f9;
    --bg-overlay: rgba(255, 255, 255, 0.95);
    --surface-primary: rgba(255, 255, 255, 0.9);
    --surface-secondary: rgba(248, 250, 252, 0.9);
    --surface-elevated: rgba(255, 255, 255, 0.95);
    
    /* Text Colors - Light Mode */
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --text-tertiary: #64748b;
    --text-inverse: #ffffff;
    --text-muted: #94a3b8;
    
    /* Border Colors - Light Mode */
    --border-primary: #e2e8f0;
    --border-secondary: #cbd5e1;
    --border-focus: #3b82f6;
    
    /* Neutral Colors */
    --white: #ffffff;
    --black: #000000;
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-400: #9ca3af;
    --gray-500: #6b7280;
    --gray-600: #4b5563;
    --gray-700: #374151;
    --gray-800: #1f2937;
    --gray-900: #111827;
    
    /* Typography */
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    
    /* Spacing */
    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-5: 1.25rem;
    --space-6: 1.5rem;
    --space-8: 2rem;
    --space-10: 2.5rem;
    --space-12: 3rem;
    
    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-full: 9999px;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    
    /* Animation */
    --transition-fast: 0.15s ease-in-out;
    --transition-normal: 0.3s ease-in-out;
    --transition-slow: 0.5s ease-in-out;
    --transition-bounce: 0.4s cubic-bezier(0.68, -0.55, 0.265, 1.55);
    
    /* Effects */
    --blur-sm: 4px;
    --blur-md: 8px;
    --blur-lg: 16px;
}

/* Dark Mode Variables */
[data-theme="dark"] {
    /* Color Palette - Dark Mode */
    --primary-gradient: linear-gradient(135deg, #4c63d2 0%, #5a4fcf 100%);
    --secondary-gradient: linear-gradient(135deg, #ec4899 0%, #be185d 100%);
    --success-gradient: linear-gradient(135deg, #059669 0%, #047857 100%);
    --warning-gradient: linear-gradient(135deg, #d97706 0%, #b45309 100%);
    --danger-gradient: linear-gradient(135deg, #dc2626 0%, #b91c1c 100%);
    --accent-gradient: linear-gradient(135deg, #0891b2 0%, #0e7490 100%);
    
    /* Theme Colors - Dark Mode */
    --bg-primary: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
    --bg-secondary: #1e293b;
    --bg-tertiary: #334155;
    --bg-overlay: rgba(15, 23, 42, 0.95);
    --surface-primary: rgba(30, 41, 59, 0.9);
    --surface-secondary: rgba(51, 65, 85, 0.9);
    --surface-elevated: rgba(71, 85, 105, 0.9);
    
    /* Text Colors - Dark Mode */
    --text-primary: #f8fafc;
    --text-secondary: #e2e8f0;
    --text-tertiary: #cbd5e1;
    --text-inverse: #0f172a;
    --text-muted: #64748b;
    
    /* Border Colors - Dark Mode */
    --border-primary: #334155;
    --border-secondary: #475569;
    --border-focus: #60a5fa;
}

/* System Theme Detection */
@media (prefers-color-scheme: dark) {
    :root:not([data-theme]) {
        /* Auto dark mode when no theme is set */
        --bg-primary: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
        --bg-secondary: #1e293b;
        --bg-tertiary: #334155;
        --bg-overlay: rgba(15, 23, 42, 0.95);
        --surface-primary: rgba(30, 41, 59, 0.9);
        --surface-secondary: rgba(51, 65, 85, 0.9);
        --surface-elevated: rgba(71, 85, 105, 0.9);
        --text-primary: #f8fafc;
        --text-secondary: #e2e8f0;
        --text-tertiary: #cbd5e1;
        --text-inverse: #0f172a;
        --text-muted: #64748b;
        --border-primary: #334155;
        --border-secondary: #475569;
        --border-focus: #60a5fa;
    }
}

/* Particle Background */
.particle-background {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    pointer-events: none;
    background: var(--bg-primary);
}

/* Global Styles */
body {
    font-family: var(--font-family);
    background: var(--bg-primary);
    min-height: 100vh;
    color: var(--text-primary);
    line-height: 1.6;
    transition: var(--transition-normal);
    position: relative;
    overflow-x: hidden;
}

/* Smooth scrolling */
html {
    scroll-behavior: smooth;
}

/* Selection styles */
::selection {
    background: rgba(102, 126, 234, 0.3);
    color: var(--text-primary);
}

/* Focus styles */
*:focus {
    outline: 2px solid var(--border-focus);
    outline-offset: 2px;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--space-6);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    position: relative;
    z-index: 1;
}

/* Header Styles */
.header {
    margin-bottom: var(--space-8);
    color: var(--text-inverse);
}

.header-top {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--space-4);
}

.logo-section {
    text-align: center;
    flex: 1;
}

.title {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: var(--space-2);
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    background: linear-gradient(45deg, #ffffff, #f0f9ff);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.subtitle {
    font-size: 1.125rem;
    opacity: 0.9;
    font-weight: 400;
}

.header-controls {
    display: flex;
    gap: var(--space-3);
    align-items: center;
}

.theme-toggle {
    background: var(--surface-primary);
    border: 2px solid var(--border-primary);
    border-radius: var(--radius-full);
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: var(--transition-bounce);
    backdrop-filter: blur(var(--blur-sm));
}

.theme-toggle:hover {
    transform: scale(1.1);
    border-color: var(--border-focus);
}

.theme-icon {
    font-size: 1.25rem;
    transition: var(--transition-normal);
}

.currency-selector select {
    background: var(--surface-primary);
    border: 2px solid var(--border-primary);
    border-radius: var(--radius-lg);
    padding: var(--space-2) var(--space-3);
    color: var(--text-primary);
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition-fast);
    backdrop-filter: blur(var(--blur-sm));
}

.currency-selector select:hover {
    border-color: var(--border-focus);
}

.currency-selector select:focus {
    border-color: var(--border-focus);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

/* Main Content */
.main-content {
    flex: 1;
    display: grid;
    gap: var(--space-8);
    grid-template-columns: 1fr;
}

/* Input Section */
.input-section {
    background: var(--surface-primary);
    padding: var(--space-8);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl), 0 0 40px rgba(255, 215, 0, 0.1);
    border: 1px solid var(--border-primary);
    backdrop-filter: blur(var(--blur-md));
    position: relative;
}

.input-section::before {
    content: '';
    position: absolute;
    top: -2px;
    left: -2px;
    right: -2px;
    bottom: -2px;
    background: linear-gradient(45deg, 
        rgba(255, 215, 0, 0.1) 0%, 
        transparent 25%, 
        transparent 75%, 
        rgba(255, 215, 0, 0.1) 100%);
    border-radius: var(--radius-xl);
    z-index: -1;
    opacity: 0;
    transition: var(--transition-normal);
}

.input-section:hover::before {
    opacity: 1;
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--space-6);
    flex-wrap: wrap;
    gap: var(--space-4);
}

.section-header h2 {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
    margin: 0;
}

.preset-buttons {
    display: flex;
    gap: var(--space-2);
    flex-wrap: wrap;
}

.preset-btn {
    background: var(--surface-secondary);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-lg);
    padding: var(--space-2) var(--space-4);
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
    cursor: pointer;
    transition: var(--transition-fast);
}

.preset-btn:hover {
    background: var(--surface-elevated);
    border-color: var(--border-focus);
    transform: translateY(-1px);
}

.input-grid {
    display: grid;
    gap: var(--space-6);
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

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

.input-group label {
    font-weight: 600;
    color: var(--text-secondary);
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 0.025em;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.label-text {
    display: flex;
    align-items: center;
    gap: var(--space-2);
}

.label-icon, .currency-symbol {
    font-size: 1rem;
    opacity: 0.8;
}

.input-wrapper {
    position: relative;
    display: flex;
    align-items: center;
}

.input-group input {
    padding: var(--space-3) var(--space-4);
    border: 2px solid var(--border-primary);
    border-radius: var(--radius-lg);
    font-size: 1rem;
    transition: var(--transition-fast);
    background: var(--surface-primary);
    color: var(--text-primary);
    flex: 1;
}

.input-group input:focus {
    outline: none;
    border-color: var(--border-focus);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.input-group input:hover {
    border-color: var(--border-secondary);
}

.input-buttons {
    display: flex;
    margin-left: var(--space-2);
    gap: var(--space-1);
}

.input-btn {
    background: var(--surface-secondary);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-md);
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: var(--transition-fast);
    font-weight: 600;
    color: var(--text-primary);
}

.input-btn:hover {
    background: var(--surface-elevated);
    transform: scale(1.1);
}

.rate-mode-toggle {
    display: flex;
    background: var(--surface-secondary);
    border-radius: var(--radius-lg);
    padding: var(--space-1);
    border: 1px solid var(--border-primary);
}

.rate-mode-btn {
    flex: 1;
    padding: var(--space-2) var(--space-4);
    background: transparent;
    border: none;
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
    cursor: pointer;
    transition: var(--transition-fast);
}

.rate-mode-btn.active {
    background: var(--surface-primary);
    color: var(--text-primary);
    box-shadow: var(--shadow-sm);
}

.duration-input {
    display: flex;
    align-items: center;
    gap: var(--space-2);
}

.duration-unit {
    color: var(--text-secondary);
    font-size: 0.875rem;
    font-weight: 500;
}

.range-input-wrapper {
    display: flex;
    align-items: center;
    gap: var(--space-3);
}

.range-input-wrapper input[type="range"] {
    flex: 1;
    height: 6px;
    border-radius: 3px;
    background: var(--surface-secondary);
    outline: none;
    -webkit-appearance: none;
}

.range-input-wrapper input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--primary-gradient);
    cursor: pointer;
    transition: var(--transition-fast);
}

.range-input-wrapper input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.2);
}

.range-input-wrapper input[type="number"] {
    width: 80px;
}

.range-label {
    color: var(--text-secondary);
    font-weight: 500;
    min-width: 20px;
}

#individualRatesContainer {
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
}

.individual-rate {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: var(--space-3);
    background: var(--surface-secondary);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-primary);
}

.individual-rate .attendee-number {
    background: var(--primary-gradient);
    color: var(--text-inverse);
    width: 32px;
    height: 32px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 0.875rem;
}

.individual-rate input {
    flex: 1;
    margin: 0;
}

/* Results Section */
.results-section {
    display: grid;
    gap: var(--space-4);
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
}

.result-pill {
    background: var(--surface-primary);
    padding: var(--space-6) var(--space-8);
    border-radius: var(--radius-full);
    box-shadow: var(--shadow-lg), 0 0 30px rgba(255, 215, 0, 0.1);
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    transition: var(--transition-normal);
    position: relative;
    overflow: hidden;
    border: 1px solid var(--border-primary);
    backdrop-filter: blur(var(--blur-sm));
}

.result-pill::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    background: radial-gradient(circle, rgba(255, 215, 0, 0.2) 0%, transparent 70%);
    border-radius: 50%;
    transform: translate(-50%, -50%);
    transition: var(--transition-normal);
    z-index: 0;
}

.result-pill:hover::after {
    width: 300px;
    height: 300px;
}

.result-pill > * {
    position: relative;
    z-index: 1;
}

.result-pill::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--success-gradient);
    transition: var(--transition-normal);
}

.result-pill.total-cost::before {
    background: var(--primary-gradient);
}

.result-pill.cost-per-minute::before {
    background: var(--success-gradient);
}

.result-pill.cost-per-second::before {
    background: var(--secondary-gradient);
}

.result-pill:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-xl);
}

.result-pill.pulse-animation {
    animation: costPulse 0.6s ease-out;
}

.result-label {
    font-size: 0.875rem;
    color: var(--text-secondary);
    font-weight: 500;
    margin-bottom: var(--space-2);
    text-transform: uppercase;
    letter-spacing: 0.025em;
}

.result-value {
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-primary);
    transition: var(--transition-fast);
}

/* Timer Section */
.timer-section {
    background: var(--surface-primary);
    padding: var(--space-8);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl), 0 0 50px rgba(255, 215, 0, 0.15);
    text-align: center;
    border: 1px solid var(--border-primary);
    backdrop-filter: blur(var(--blur-md));
    position: relative;
}

.timer-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, 
        rgba(255, 215, 0, 0.05) 0%, 
        transparent 50%, 
        rgba(255, 215, 0, 0.05) 100%);
    border-radius: var(--radius-xl);
    pointer-events: none;
    opacity: 0;
    transition: var(--transition-slow);
}

.timer-section.timer-active::before {
    opacity: 1;
}

.timer-display {
    margin-bottom: var(--space-6);
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-8);
    align-items: center;
}

.timer-info, .cost-display {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.timer-label, .cost-label {
    font-size: 0.875rem;
    color: var(--text-secondary);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.025em;
    margin-bottom: var(--space-2);
}

.timer-value {
    font-size: 3.5rem;
    font-weight: 700;
    color: var(--text-primary);
    font-feature-settings: 'tnum';
    transition: var(--transition-fast);
}

.timer-cost {
    font-size: 2.5rem;
    font-weight: 700;
    background: var(--warning-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    transition: var(--transition-fast);
}

.cost-breakdown {
    margin-top: var(--space-2);
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.cost-breakdown-item {
    background: var(--surface-secondary);
    padding: var(--space-1) var(--space-3);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-primary);
}

.timer-progress {
    margin-bottom: var(--space-6);
}

.progress-bar {
    position: relative;
    height: 8px;
    background: var(--surface-secondary);
    border-radius: var(--radius-md);
    overflow: hidden;
    border: 1px solid var(--border-primary);
}

.progress-fill {
    height: 100%;
    background: var(--success-gradient);
    transition: width var(--transition-fast);
    border-radius: var(--radius-md);
}

.progress-milestones {
    display: flex;
    justify-content: space-between;
    margin-top: var(--space-2);
    position: relative;
}

.milestone {
    font-size: 0.75rem;
    color: var(--text-tertiary);
    background: var(--surface-secondary);
    padding: var(--space-1) var(--space-2);
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-primary);
    transition: var(--transition-fast);
}

.milestone.reached {
    color: var(--text-primary);
    background: var(--success-gradient);
    border-color: transparent;
    animation: milestoneReached 0.5s ease-out;
}

.timer-controls {
    display: flex;
    gap: var(--space-4);
    justify-content: center;
    flex-wrap: wrap;
}

/* Button Styles */
.btn {
    padding: var(--space-3) var(--space-6);
    border: none;
    border-radius: var(--radius-lg);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition-bounce);
    min-width: 140px;
    position: relative;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none !important;
}

.btn:not(:disabled):hover {
    transform: translateY(-2px) scale(1.02);
}

.btn:not(:disabled):active {
    transform: translateY(0) scale(0.98);
}

.btn-icon {
    font-size: 1.125rem;
}

.btn-text {
    font-weight: 600;
}

.btn-primary {
    background: var(--success-gradient);
    color: var(--text-inverse);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background: var(--warning-gradient);
    color: var(--text-inverse);
    box-shadow: var(--shadow-md);
}

.btn-tertiary {
    background: var(--surface-secondary);
    color: var(--text-primary);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-primary);
}

.btn-outline {
    background: transparent;
    color: var(--text-primary);
    border: 2px solid var(--border-primary);
}

.btn-tertiary:hover:not(:disabled) {
    background: var(--surface-elevated);
}

.btn-outline:hover:not(:disabled) {
    background: var(--surface-secondary);
    border-color: var(--border-focus);
}

/* Alert Styles */
.alert-container {
    position: fixed;
    top: var(--space-6);
    right: var(--space-6);
    z-index: 1000;
    pointer-events: none;
}

.alert {
    background: var(--white);
    border-left: 4px solid #f59e0b;
    padding: var(--space-4) var(--space-6);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    display: flex;
    align-items: center;
    gap: var(--space-3);
    max-width: 400px;
    pointer-events: all;
    opacity: 0;
    transform: translateX(100%);
    transition: var(--transition-normal);
}

.alert.show {
    opacity: 1;
    transform: translateX(0);
    animation: slideInBounce 0.5s ease-out;
}

.alert.danger {
    border-left-color: #ef4444;
}

.alert-icon {
    font-size: 1.25rem;
    flex-shrink: 0;
}

.alert-message {
    flex: 1;
    font-weight: 500;
    color: var(--gray-700);
}

.alert-close {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--gray-400);
    padding: 0;
    line-height: 1;
    transition: var(--transition-fast);
}

.alert-close:hover {
    color: var(--gray-600);
}

/* Animations */
@keyframes slideInBounce {
    0% {
        opacity: 0;
        transform: translateX(100%);
    }
    60% {
        opacity: 1;
        transform: translateX(-10px);
    }
    100% {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes pulse {
    0%, 100% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.05);
    }
}

@keyframes costPulse {
    0% {
        transform: scale(1);
        box-shadow: var(--shadow-lg);
    }
    50% {
        transform: scale(1.08);
        box-shadow: var(--shadow-xl), 0 0 30px rgba(102, 126, 234, 0.3);
    }
    100% {
        transform: scale(1);
        box-shadow: var(--shadow-lg);
    }
}

@keyframes milestoneReached {
    0% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.2);
    }
    100% {
        transform: scale(1);
    }
}

@keyframes timerPulse {
    0%, 100% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.02);
        color: #ef4444;
    }
}

@keyframes shimmer {
    0% {
        background-position: -200px 0;
    }
    100% {
        background-position: calc(200px + 100%) 0;
    }
}

.pulse {
    animation: pulse 2s infinite;
}

.timer-pulse {
    animation: timerPulse 1s infinite;
}

.shimmer {
    background: linear-gradient(
        90deg,
        transparent,
        rgba(255, 255, 255, 0.2),
        transparent
    );
    background-size: 200px 100%;
    animation: shimmer 2s infinite;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: var(--space-4);
    }
    
    .header-top {
        flex-direction: column;
        text-align: center;
    }
    
    .title {
        font-size: 2.5rem;
    }
    
    .input-section {
        padding: var(--space-6);
    }
    
    .input-grid {
        grid-template-columns: 1fr;
    }
    
    .section-header {
        flex-direction: column;
        align-items: stretch;
        text-align: center;
    }
    
    .preset-buttons {
        justify-content: center;
    }
    
    .timer-section {
        padding: var(--space-6);
    }
    
    .timer-display {
        grid-template-columns: 1fr;
        gap: var(--space-4);
    }
    
    .timer-value {
        font-size: 2.5rem;
    }
    
    .timer-cost {
        font-size: 2rem;
    }
    
    .timer-controls {
        flex-direction: column;
        align-items: center;
        gap: var(--space-3);
    }
    
    .btn {
        min-width: 100%;
        max-width: 280px;
    }
    
    .alert-container {
        top: var(--space-4);
        right: var(--space-4);
        left: var(--space-4);
    }
    
    .alert {
        max-width: none;
    }
    
    .range-input-wrapper {
        flex-direction: column;
        gap: var(--space-2);
    }
    
    .range-input-wrapper input[type="range"] {
        order: 2;
    }
    
    .range-input-wrapper input[type="number"] {
        order: 1;
        width: 100%;
    }
}

@media (max-width: 480px) {
    .title {
        font-size: 2rem;
    }
    
    .subtitle {
        font-size: 1rem;
    }
    
    .timer-value {
        font-size: 2.5rem;
    }
    
    .result-value {
        font-size: 1.5rem;
    }
    
    .results-section {
        grid-template-columns: 1fr;
    }
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    .result-pill::before {
        height: 6px;
    }
    
    .btn {
        border: 2px solid transparent;
    }
    
    .btn-primary {
        border-color: var(--gray-800);
    }
}

/* Reduced motion support */
@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: white;
        color: black;
    }
    
    .timer-controls,
    .alert-container {
        display: none;
    }
}