:root {
    /* Apple-inspired color palette */
    --primary-color: #0071e3; /* Apple blue */
    --secondary-color: #1d1d1f; /* Apple dark gray */
    --accent-color: #fa5252; /* Donation red */
    --success-color: #34c759; /* Apple green */
    --warning-color: #ff9f0a; /* Apple orange */
    --danger-color: #ff3b30; /* Apple red */
    --background-color: #000000; /* Deep black */
    --surface-color: #141414; /* Slightly lighter black for cards */
    --card-background: rgba(30, 30, 32, 0.7); /* Translucent dark background */
    --text-primary: #f5f5f7; /* Apple off-white text */
    --text-secondary: #86868b; /* Apple secondary text */
    --text-light: #ffffff; /* Pure white text */
    --border-color: #333336; /* Subtle border */
    --border-radius: 12px; /* More rounded corners */
    --box-shadow: 0 8px 20px rgba(0, 0, 0, 0.5); /* More pronounced shadow */
    --subtle-shadow: 0 2px 10px rgba(0, 0, 0, 0.2); /* Subtle shadow for elements */
    --glass-effect: rgba(255, 255, 255, 0.08); /* Subtle glass effect */
    --transition-speed: 0.3s;
    
    /* Glass morphism variables */
    --glass-background: rgba(30, 30, 32, 0.7);
    --glass-border: rgba(255, 255, 255, 0.1);
    --glass-shadow: 0 4px 30px rgba(0, 0, 0, 0.1);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'SF Pro Text', 'SF Pro Display', 'Helvetica Neue', Arial, sans-serif;
    color: var(--text-primary);
    background-color: var(--background-color);
    line-height: 1.5;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    letter-spacing: -0.02em;
}

/* Custom styles for drink equivalent table headers */
.drink-equivalents .list-group-item.header-row {
    background-color: var(--surface-color) !important;
    color: var(--text-light) !important;
    padding: 3px 10px !important;
    font-size: 0.8rem !important;
    border-color: var(--border-color) !important;
}

.content {
    flex-grow: 1;
}

h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    margin-bottom: 1rem;
    letter-spacing: -0.03em;
    color: var(--text-light);
}

h1 {
    font-size: 2.5rem;
    line-height: 1.2;
}

h2 {
    font-size: 2rem;
    line-height: 1.25;
}

h3 {
    font-size: 1.75rem;
    line-height: 1.3;
}

h4 {
    font-size: 1.5rem;
    line-height: 1.35;
}

a {
    color: var(--primary-color);
    text-decoration: none;
    transition: color var(--transition-speed);
}

a:hover {
    color: #0056b3;
}

/* Navbar styling */
.navbar {
    background-color: var(--surface-color);
    border-bottom: 1px solid var(--border-color);
    box-shadow: var(--subtle-shadow);
    padding: 0.75rem 0;
}

.navbar-brand {
    color: var(--text-light);
    font-weight: 600;
    font-size: 1.25rem;
}

.navbar-nav .nav-link {
    color: var(--text-secondary);
    font-weight: 500;
    padding: 0.5rem 1rem;
    transition: color var(--transition-speed);
}

.navbar-nav .nav-link:hover, 
.navbar-nav .nav-link.active {
    color: var(--text-light);
}

.navbar-nav .nav-link.btn-primary {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
    color: white;
    border-radius: 8px;
    padding: 0.375rem 1rem;
    margin-left: 0.5rem;
}

.navbar-nav .nav-link.btn-primary:hover {
    background-color: #0062cc;
    border-color: #0062cc;
}

/* Card styling */
.card {
    background-color: var(--surface-color);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--subtle-shadow);
    transition: transform 0.3s, box-shadow 0.3s;
}

.card:hover {
    box-shadow: var(--box-shadow);
}

.card-header {
    background-color: var(--surface-color);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 1.25rem;
}

.card-body {
    padding: 1.25rem;
}

.card.glass {
    background-color: var(--glass-background);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
}

/* Button styling */
.btn {
    font-weight: 500;
    border-radius: 8px;
    padding: 0.5rem 1.25rem;
    transition: all var(--transition-speed);
}

.btn-primary {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
}

.btn-primary:hover, .btn-primary:focus {
    background-color: #0062cc;
    border-color: #0062cc;
}

.btn-secondary {
    background-color: var(--secondary-color);
    border-color: var(--border-color);
}

.btn-secondary:hover, .btn-secondary:focus {
    background-color: #2d2d30;
    border-color: #444;
}

.btn-success {
    background-color: var(--success-color);
    border-color: var(--success-color);
}

.btn-success:hover, .btn-success:focus {
    background-color: #2cb14c;
    border-color: #2cb14c;
}

.btn-outline-light {
    color: var(--text-light);
    border-color: var(--border-color);
}

.btn-outline-light:hover, .btn-outline-light:focus {
    background-color: rgba(255, 255, 255, 0.05);
    color: var(--text-light);
}

/* Form styling */
.form-control, .form-select {
    background-color: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-primary);
    padding: 0.6rem 1rem;
    transition: border-color var(--transition-speed), box-shadow var(--transition-speed);
}

.form-control:focus, .form-select:focus {
    background-color: rgba(255, 255, 255, 0.08);
    border-color: var(--primary-color);
    box-shadow: 0 0 0 0.25rem rgba(0, 113, 227, 0.15);
    color: var(--text-primary);
}

.form-control::placeholder {
    color: var(--text-secondary);
    opacity: 0.7;
}

.form-label {
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.form-text {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.form-check-input {
    background-color: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
}

.form-check-input:checked {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
}

.input-group-text {
    background-color: rgba(255, 255, 255, 0.08);
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
}

/* Alert styling */
.alert {
    border-radius: var(--border-radius);
    border: none;
    padding: 0.75rem 1.25rem;
}

.alert-primary {
    background-color: rgba(0, 113, 227, 0.15);
    color: #8fc9ff;
    border-left: 4px solid var(--primary-color);
}

.alert-secondary {
    background-color: rgba(29, 29, 31, 0.5);
    color: var(--text-secondary);
    border-left: 4px solid var(--secondary-color);
}

.alert-success {
    background-color: rgba(52, 199, 89, 0.15);
    color: #7ee6a1;
    border-left: 4px solid var(--success-color);
}

.alert-warning {
    background-color: rgba(255, 159, 10, 0.15);
    color: #ffc66b;
    border-left: 4px solid var(--warning-color);
}

.alert-danger {
    background-color: rgba(255, 59, 48, 0.15);
    color: #ff8983;
    border-left: 4px solid var(--danger-color);
}

/* List group styling */
.list-group-item {
    background-color: var(--surface-color);
    border-color: var(--border-color);
    color: var(--text-primary);
}

.list-group-item-action:hover, .list-group-item-action:focus {
    background-color: rgba(255, 255, 255, 0.05);
    color: var(--text-primary);
}

.list-group-item.active {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
}

/* Badge styling */
.badge {
    font-weight: 500;
    padding: 0.35em 0.65em;
    border-radius: 6px;
}

/* Dropdown styling */
.dropdown-menu {
    background-color: var(--surface-color);
    border: 1px solid var(--border-color);
    border-radius: 10px;
    box-shadow: var(--box-shadow);
    padding: 0.5rem;
}

.dropdown-item {
    color: var(--text-primary);
    padding: 0.5rem 1rem;
    border-radius: 6px;
}

.dropdown-item:hover, .dropdown-item:focus {
    background-color: rgba(255, 255, 255, 0.05);
    color: var(--text-light);
}

.dropdown-divider {
    border-top: 1px solid var(--border-color);
}

/* Modal styling */
.modal-content {
    background-color: var(--surface-color);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
}

.modal-header, .modal-footer {
    border-color: var(--border-color);
}

.modal-title {
    color: var(--text-light);
}

.btn-close {
    filter: invert(1);
}

/* Time display styling */
.time-display {
    background-color: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-light);
    font-size: 1.5rem;
    font-weight: 600;
    text-align: center;
    padding: 0.5rem;
    margin-bottom: 1rem;
}

.time-control-button {
    background-color: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    border-radius: 8px;
    width: 38px;
    height: 38px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-speed);
}

.time-control-button:hover {
    background-color: rgba(255, 255, 255, 0.1);
    color: var(--text-light);
}

/* Custom animation for calculation results */
.card-animate {
    animation: fadeInUp 0.5s ease-out;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Results display */
.results-display-container {
    background-color: rgba(255, 255, 255, 0.05);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
}

.results-display {
    font-size: 3rem;
    font-weight: 700;
    color: var(--text-light);
    margin: 1rem 0;
    letter-spacing: -0.03em;
}

.view-details-link {
    color: var(--text-secondary);
    text-decoration: underline;
    font-size: 0.9rem;
}

.view-details-link:hover {
    color: var(--text-light);
}

/* Drink item styling */
.drink-item {
    background-color: var(--surface-color);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    margin-bottom: 1rem;
    padding: 1rem;
    transition: all var(--transition-speed);
    position: relative;
}

.drink-item:hover {
    background-color: rgba(255, 255, 255, 0.02);
    border-color: rgba(255, 255, 255, 0.1);
}

.drink-name {
    font-weight: 600;
    color: var(--text-light);
    margin-bottom: 0.5rem;
}

.drink-details {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.drink-units {
    font-weight: 600;
    color: var(--primary-color);
}

.favorite-toggle {
    position: absolute;
    top: 1rem;
    right: 1rem;
    color: #bbb;
    background: none;
    border: none;
    cursor: pointer;
    transition: color var(--transition-speed);
}

.favorite-toggle:hover {
    color: #ffbb00;
}

.favorite-toggle.active {
    color: #ffbb00;
}

/* Glossy card effect */
.glass-card {
    background: var(--glass-background);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-radius: var(--border-radius);
    border: 1px solid var(--glass-border);
    box-shadow: var(--glass-shadow);
    transition: all var(--transition-speed);
}

.glass-card:hover {
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
    border-color: rgba(255, 255, 255, 0.2);
}

/* Footer styling */
footer {
    background-color: var(--surface-color);
    border-top: 1px solid var(--border-color);
    color: var(--text-secondary);
    padding: 1.5rem 0;
    margin-top: 3rem;
}

.footer-link {
    color: var(--text-secondary);
    margin: 0 0.75rem;
    transition: color var(--transition-speed);
}

.footer-link:hover {
    color: var(--text-light);
    text-decoration: none;
}

.footer-brand {
    font-weight: 600;
    color: var(--text-light);
}

/* Loading overlay for payments */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.7);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 9999;
    backdrop-filter: blur(5px);
    -webkit-backdrop-filter: blur(5px);
}

.loading-spinner {
    width: 50px;
    height: 50px;
    border: 5px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: var(--primary-color);
    animation: spin 1s ease-in-out infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.loading-text {
    color: var(--text-light);
    margin-top: 20px;
    font-weight: 500;
}

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

/* Tip Modal */
.tip-amount-option {
    background-color: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 1rem;
    transition: all var(--transition-speed);
    cursor: pointer;
    text-align: center;
}

.tip-amount-option:hover {
    background-color: rgba(255, 255, 255, 0.1);
    border-color: var(--primary-color);
}

.tip-amount-option.selected {
    background-color: rgba(0, 113, 227, 0.2);
    border-color: var(--primary-color);
}

.tip-amount {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-light);
}

.tip-description {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-top: 0.5rem;
}

/* Password dots color fix */
input[type="password"] {
    color: white !important;
}

/* Media queries */
@media (max-width: 768px) {
    .results-display {
        font-size: 2.5rem;
    }
    
    .time-display {
        font-size: 1.25rem;
    }
}

@media (max-width: 576px) {
    .card-body {
        padding: 1rem;
    }
    
    .results-display {
        font-size: 2rem;
    }
}

/* Admin dashboard specific styles */
.stats-card {
    background-color: var(--surface-color);
    border-radius: var(--border-radius);
    border: 1px solid var(--border-color);
    padding: 1.5rem;
    text-align: center;
    transition: all var(--transition-speed);
}

.stats-card:hover {
    box-shadow: var(--box-shadow);
    border-color: rgba(255, 255, 255, 0.1);
}

.stats-icon {
    color: var(--text-secondary);
    font-size: 2rem;
    margin-bottom: 1rem;
}

.stats-number {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--text-light);
    margin-bottom: 0.5rem;
}

.stats-label {
    color: var(--text-secondary);
    font-size: 1rem;
}

.chart-container {
    background-color: var(--surface-color);
    border-radius: var(--border-radius);
    border: 1px solid var(--border-color);
    padding: 1.5rem;
    margin-bottom: 2rem;
    box-shadow: var(--subtle-shadow);
}

.chart-title {
    color: var(--text-light);
    font-weight: 600;
    margin-bottom: 1.5rem;
}

/* Page transition animation */
body {
    animation: fadeIn 0.3s ease-in;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}