:root {
    /* Modern Color Scheme - Black with complementary colors */
    --primary-color: #000000;
    --primary-dark: #1a1a1a;
    --secondary-color: #333333;
    --accent-color: #6366f1; /* Modern indigo accent */
    --accent-light: #818cf8;
    --success-color: #10b981; /* Modern green */
    --warning-color: #f59e0b; /* Modern amber */
    --error-color: #ef4444; /* Modern red */
    
    /* Background Colors */
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-card: #ffffff;
    --bg-dark: #000000;
    --bg-dark-soft: #1e293b; /* Softer dark background */
    --bg-gray: #f1f5f9;
    --bg-gradient: linear-gradient(135deg, #000000 0%, #1e293b 50%, #334155 100%);
    
    /* Text Colors */
    --text-primary: #000000;
    --text-secondary: #475569;
    --text-muted: #64748b;
    --text-white: #ffffff;
    --text-inverse: #ffffff;
    
    /* Border Colors */
    --border-light: #e2e8f0;
    --border-medium: #cbd5e1;
    --border-dark: #334155;
    
    /* Shadows */
    --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.1);
    --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);
    
    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    
    /* Transitions */
    --transition-fast: 150ms ease-in-out;
    --transition-normal: 250ms ease-in-out;
    --transition-slow: 350ms ease-in-out;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Compact Modern Header Styles */
.main-header {
    background: var(--bg-gradient);
    color: var(--text-white);
    padding: 1.5rem 0; /* Reduced from 2rem */
    position: relative;
    overflow: hidden;
}

.main-header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, rgba(0,0,0,0.9) 0%, rgba(30,41,59,0.95) 50%, rgba(51,65,85,0.9) 100%);
}

.header-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    position: relative;
    z-index: 2;
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1rem; /* Reduced from 2rem */
    animation: fadeInDown 0.8s ease-out;
}

.header-icon {
    width: 60px; /* Reduced from 80px */
    height: 60px;
    background: linear-gradient(135deg, var(--accent-color) 0%, var(--accent-light) 100%);
    color: var(--text-white);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.8rem; /* Reduced from 2.5rem */
    margin-right: 1.5rem; /* Reduced from 2rem */
    box-shadow: var(--shadow-xl);
    animation: pulse 2s infinite;
    border: 3px solid rgba(255, 255, 255, 0.2);
}

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

.header-title {
    font-size: 2.5rem; /* Reduced from 3.5rem */
    font-weight: 800;
    margin-bottom: 0.25rem; /* Reduced from 0.5rem */
    background: linear-gradient(135deg, #ffffff 0%, var(--accent-light) 50%, #ffffff 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.header-subtitle {
    font-size: 1rem; /* Reduced from 1.25rem */
    color: rgba(255, 255, 255, 0.8);
    font-weight: 300;
}

.header-stats {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 1.5rem; /* Reduced from 2rem */
    animation: fadeInUp 0.8s ease-out 0.3s both;
}

.stat-item {
    text-align: center;
    padding: 0.75rem 1rem;
    background: rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-lg);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    transition: all var(--transition-normal);
}

.stat-item:hover {
    background: rgba(255, 255, 255, 0.15);
    transform: translateY(-2px);
}

.stat-number {
    font-size: 1.5rem; /* Reduced from 2rem */
    font-weight: 700;
    color: var(--text-white);
    margin-bottom: 0.1rem; /* Reduced from 0.25rem */
}

.stat-label {
    font-size: 0.75rem; /* Reduced from 0.875rem */
    color: rgba(255, 255, 255, 0.7);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.stat-divider {
    display: none; /* Remove dividers for cleaner look */
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem 1rem; /* Reduced from 3rem */
}

.converter-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    margin-bottom: 3rem;
}

.card {
    background: var(--bg-card);
    border-radius: var(--radius-xl);
    padding: 2rem;
    box-shadow: var(--shadow-lg);
    border: 2px solid var(--border-light);
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--accent-color) 0%, var(--accent-light) 100%);
}

.card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
    border-color: var(--accent-color);
}

.card-header {
    display: flex;
    align-items: center;
    margin-bottom: 1.5rem;
}

.card-icon {
    width: 48px;
    height: 48px;
    background: linear-gradient(135deg, var(--accent-color) 0%, var(--accent-light) 100%);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-white);
    font-size: 1.25rem;
    margin-right: 1rem;
    box-shadow: var(--shadow-md);
}

.card-title {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-label {
    display: block;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 1rem;
}

.input-group {
    position: relative;
}

.form-input, .form-select {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 2px solid var(--border-light);
    border-radius: var(--radius-md);
    font-size: 1rem;
    transition: all var(--transition-fast);
    background: var(--bg-secondary);
    color: var(--text-primary);
}

.form-input:focus, .form-select:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
    background: var(--bg-card);
}

.form-input:hover, .form-select:hover {
    border-color: var(--border-medium);
}

.input-icon {
    position: absolute;
    right: 0.75rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-muted);
    pointer-events: none;
}

.result-card {
    background: var(--bg-gradient);
    color: var(--text-white);
    text-align: center;
    padding: 2rem;
    border-radius: var(--radius-xl);
    margin-top: 2rem;
    box-shadow: var(--shadow-lg);
    animation: slideInUp 0.5s ease-out;
    border: 2px solid var(--accent-color);
    position: relative;
    overflow: hidden;
}

.result-card::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: linear-gradient(45deg, transparent, rgba(99, 102, 241, 0.1), transparent);
    transform: rotate(45deg);
    animation: shimmer 3s infinite;
}

.result-date {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    position: relative;
    z-index: 1;
}

.result-label {
    font-size: 1rem;
    opacity: 0.8;
    text-transform: uppercase;
    letter-spacing: 1px;
    position: relative;
    z-index: 1;
}

.swap-button {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 60px;
    height: 60px;
    background: var(--bg-gradient);
    border: 2px solid var(--accent-color);
    border-radius: 50%;
    color: var(--text-white);
    font-size: 1.5rem;
    cursor: pointer;
    box-shadow: var(--shadow-lg);
    transition: all var(--transition-normal);
    z-index: 1000;
}

.swap-button:hover {
    transform: rotate(180deg) scale(1.1);
    box-shadow: var(--shadow-xl);
    background: var(--accent-color);
}

.error-message {
    background: linear-gradient(135deg, var(--error-color) 0%, #dc2626 100%);
    color: var(--text-white);
    padding: 1rem;
    border-radius: var(--radius-md);
    margin-top: 1rem;
    display: none;
    animation: shake 0.5s ease-in-out;
    border: 2px solid #fca5a5;
}

.info-panel {
    background: var(--bg-card);
    border-radius: var(--radius-xl);
    padding: 2rem;
    box-shadow: var(--shadow-md);
    margin-top: 2rem;
    border: 2px solid var(--border-light);
}

.info-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
}

.info-item {
    text-align: center;
    padding: 1.5rem;
    border-radius: var(--radius-lg);
    background: var(--bg-gray);
    border: 2px solid var(--border-light);
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.info-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent-color) 0%, var(--success-color) 50%, var(--warning-color) 100%);
}

.info-item:hover {
    transform: translateY(-4px);
    border-color: var(--accent-color);
    box-shadow: var(--shadow-md);
    background: var(--bg-card);
}

.info-item i {
    font-size: 2rem;
    color: var(--accent-color);
    margin-bottom: 1rem;
    display: block;
}

.info-item h3 {
    color: var(--text-primary);
    font-size: 1.25rem;
    margin-bottom: 0.5rem;
    font-weight: 600;
}

.info-item p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.calendar-mode-toggle {
    display: flex;
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: 0.5rem;
    margin-bottom: 2rem;
    box-shadow: var(--shadow-sm);
    border: 2px solid var(--border-light);
}

.toggle-option {
    flex: 1;
    padding: 0.75rem 1rem;
    text-align: center;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
    font-weight: 500;
}

.toggle-option.active {
    background: var(--accent-color);
    color: var(--text-white);
    box-shadow: var(--shadow-sm);
}

.toggle-option:not(.active) {
    color: var(--text-secondary);
}

.toggle-option:not(.active):hover {
    background: var(--bg-gray);
    color: var(--text-primary);
    transform: translateY(-1px);
}

/* Animation Keyframes */
@keyframes fadeInDown {
    from {
        opacity: 0;
        transform: translateY(-30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    25% { transform: translateX(-5px); }
    75% { transform: translateX(5px); }
}

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

@keyframes shimmer {
    0% { transform: translateX(-100%) translateY(-100%) rotate(45deg); }
    100% { transform: translateX(100%) translateY(100%) rotate(45deg); }
}
/* Quick Dates Styles - Updated with Modern Design */
.quick-dates {
    margin-top: 1.5rem;
    padding: 1.5rem;
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    border: 2px solid var(--border-light);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.quick-dates::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent-color) 0%, var(--success-color) 50%, var(--warning-color) 100%);
}

.quick-dates:hover {
    border-color: var(--accent-color);
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.quick-dates-title {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 1rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.quick-dates-title::before {
    content: '⚡';
    font-size: 1rem;
}

.quick-dates-buttons {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
}

.quick-date-btn {
    padding: 0.75rem 1.25rem;
    background: var(--bg-secondary);
    border: 2px solid var(--border-light);
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    cursor: pointer;
    transition: all var(--transition-normal);
    color: var(--text-primary);
    font-weight: 500;
    position: relative;
    overflow: hidden;
    min-width: 100px;
    text-align: center;
}

.quick-date-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(99, 102, 241, 0.1), transparent);
    transition: left var(--transition-normal);
}

.quick-date-btn:hover {
    background: var(--accent-color);
    color: var(--text-white);
    transform: translateY(-3px);
    box-shadow: var(--shadow-md);
    border-color: var(--accent-color);
}

.quick-date-btn:hover::before {
    left: 100%;
}

.quick-date-btn:active {
    transform: translateY(-1px);
    box-shadow: var(--shadow-sm);
}

/* Special styling for different quick date types */
.quick-date-btn[data-type="today"] {
    background: linear-gradient(135deg, var(--success-color) 0%, #059669 100%);
    color: var(--text-white);
    border-color: var(--success-color);
}

.quick-date-btn[data-type="today"]:hover {
    background: linear-gradient(135deg, #059669 0%, #047857 100%);
    transform: translateY(-3px) scale(1.05);
}

.quick-date-btn[data-type="new-year"] {
    background: linear-gradient(135deg, var(--warning-color) 0%, #d97706 100%);
    color: var(--text-white);
    border-color: var(--warning-color);
}

.quick-date-btn[data-type="new-year"]:hover {
    background: linear-gradient(135deg, #d97706 0%, #b45309 100%);
    transform: translateY(-3px) scale(1.05);
}

.quick-date-btn[data-type="holiday"] {
    background: linear-gradient(135deg, #8b5cf6 0%, #7c3aed 100%);
    color: var(--text-white);
    border-color: #8b5cf6;
}

.quick-date-btn[data-type="holiday"]:hover {
    background: linear-gradient(135deg, #7c3aed 0%, #6d28d9 100%);
    transform: translateY(-3px) scale(1.05);
}

/* Loading state for quick date buttons */
.quick-date-btn.loading {
    pointer-events: none;
    opacity: 0.7;
    position: relative;
}

.quick-date-btn.loading::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 16px;
    height: 16px;
    margin: -8px 0 0 -8px;
    border: 2px solid transparent;
    border-top: 2px solid currentColor;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

/* Responsive design for quick dates */
@media (max-width: 768px) {
    .quick-dates {
        padding: 1.25rem;
        margin-top: 1.25rem;
    }
    
    .quick-dates-buttons {
        gap: 0.5rem;
    }
    
    .quick-date-btn {
        padding: 0.625rem 1rem;
        font-size: 0.8rem;
        min-width: 80px;
        flex: 1;
    }
    
    .quick-dates-title {
        font-size: 0.8rem;
        margin-bottom: 0.75rem;
    }
}

@media (max-width: 480px) {
    .quick-dates {
        padding: 1rem;
        margin-top: 1rem;
    }
    
    .quick-dates-buttons {
        gap: 0.5rem;
        justify-content: center;
    }
    
    .quick-date-btn {
        padding: 0.5rem 0.75rem;
        font-size: 0.75rem;
        min-width: 70px;
        flex: 1;
        max-width: calc(50% - 0.25rem);
    }
    
    .quick-dates-title {
        font-size: 0.75rem;
        text-align: center;
        margin-bottom: 0.75rem;
    }
}

/* Enhanced animations */
@keyframes quickDatePulse {
    0%, 100% { 
        transform: scale(1); 
        box-shadow: var(--shadow-sm);
    }
    50% { 
        transform: scale(1.02); 
        box-shadow: var(--shadow-md);
    }
}

.quick-date-btn:focus {
    outline: none;
    animation: quickDatePulse 0.6s ease-in-out;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
}

/* Dark mode support for quick dates (if needed) */
@media (prefers-color-scheme: dark) {
    .quick-dates {
        background: var(--bg-dark-soft);
        border-color: var(--border-dark);
    }
    
    .quick-dates-title {
        color: var(--text-white);
    }
    
    .quick-date-btn {
        background: var(--secondary-color);
        color: var(--text-white);
        border-color: var(--border-dark);
    }
}
/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 1rem;
    }

    .header-container {
        padding: 0 1rem;
    }

    .main-header {
        padding: 1rem 0; /* Further reduced for mobile */
    }

    .header-content {
        flex-direction: column;
        text-align: center;
        margin-bottom: 0.75rem; /* Reduced */
    }

    .header-icon {
        width: 50px; /* Smaller on mobile */
        height: 50px;
        margin-right: 0;
        margin-bottom: 0.75rem; /* Reduced */
        font-size: 1.5rem;
    }

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

    .header-title {
        font-size: 1.75rem; /* Much smaller on mobile */
        margin-bottom: 0.25rem;
    }

    .header-subtitle {
        font-size: 0.875rem; /* Smaller on mobile */
    }

    .header-stats {
        gap: 0.75rem; /* Reduced gap */
    }

    .stat-item {
        padding: 0.5rem 0.75rem; /* Smaller padding */
    }

    .stat-number {
        font-size: 1.25rem; /* Smaller */
    }

    .stat-label {
        font-size: 0.625rem; /* Much smaller */
    }

    .converter-container {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .form-row {
        grid-template-columns: 1fr;
        gap: 0.75rem;
    }

    .card {
        padding: 1.5rem;
    }

    .swap-button {
        bottom: 1rem;
        right: 1rem;
        width: 50px;
        height: 50px;
        font-size: 1.25rem;
    }

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

@media (max-width: 480px) {
    .main-header {
        padding: 0.75rem 0; /* Even more compact for small screens */
    }

    .header-title {
        font-size: 1.5rem; /* Very compact */
    }

    .header-subtitle {
        font-size: 0.8rem;
    }

    .header-icon {
        width: 40px;
        height: 40px;
        font-size: 1.25rem;
        margin-bottom: 0.5rem;
    }

    .header-stats {
        gap: 0.5rem;
    }

    .stat-item {
        padding: 0.375rem 0.5rem;
    }

    .stat-number {
        font-size: 1rem;
    }

    .stat-label {
        font-size: 0.5rem;
    }
}