/* Apple Minimalist Design System for Class Score Management System */

:root {
    /* Apple Minimalist Color Palette */
    --color-primary: #0071e3;
    --color-primary-light: #4da3ff;
    --color-primary-dark: #0056b3;
    --color-primary-50: #f0f7ff;
    --color-primary-100: #e0f0ff;
    --color-primary-200: #b3d9ff;
    
    --color-secondary: #5856d6;
    --color-secondary-light: #8a84ff;
    --color-secondary-dark: #4338ca;
    
    --color-success: #34c759;
    --color-success-light: #5cd67d;
    --color-success-dark: #28a745;
    --color-success-bg: #e8f5e9;
    
    --color-warning: #ff9500;
    --color-warning-light: #ffb340;
    --color-warning-dark: #e67e00;
    --color-warning-bg: #fff8e1;
    
    --color-danger: #ff3b30;
    --color-danger-light: #ff6b5f;
    --color-danger-dark: #d63027;
    --color-danger-bg: #ffebee;
    
    --color-info: #5ac8fa;
    --color-info-light: #8dd4fd;
    --color-info-dark: #4a9fd4;
    --color-info-bg: #e3f2fd;
    
    /* Neutral Grays - Apple Style */
    --color-gray-50: #fafafa;
    --color-gray-100: #f5f5f7;
    --color-gray-200: #e5e5ea;
    --color-gray-300: #d1d1d6;
    --color-gray-400: #aeaeb2;
    --color-gray-500: #8e8e93;
    --color-gray-600: #636366;
    --color-gray-700: #48484a;
    --color-gray-800: #3a3a3c;
    --color-gray-900: #1d1d1f;
    
    /* Text Colors */
    --color-text-primary: #1d1d1f;
    --color-text-secondary: #6e6e73;
    --color-text-muted: #86868b;
    --color-text-inverse: #ffffff;
    
    /* Background Colors */
    --color-bg-primary: #ffffff;
    --color-bg-secondary: #f5f5f7;
    --color-bg-tertiary: #fafafa;
    
    /* Border Colors */
    --color-border: #e5e5ea;
    --color-border-light: #f5f5f7;
    --color-border-dark: #d1d1d6;
    
    /* Shadows - Subtle and Refined */
    --shadow-xs: 0 1px 2px 0 rgba(0, 0, 0, 0.04);
    --shadow-sm: 0 2px 4px 0 rgba(0, 0, 0, 0.06), 0 1px 2px -1px rgba(0, 0, 0, 0.04);
    --shadow-md: 0 4px 8px 0 rgba(0, 0, 0, 0.08), 0 2px 4px -2px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 8px 16px 0 rgba(0, 0, 0, 0.1), 0 4px 8px -4px rgba(0, 0, 0, 0.08);
    --shadow-xl: 0 16px 32px 0 rgba(0, 0, 0, 0.12), 0 8px 16px -8px rgba(0, 0, 0, 0.1);
    --shadow-2xl: 0 24px 48px 0 rgba(0, 0, 0, 0.15);
    --shadow-inner: inset 0 2px 4px 0 rgba(0, 0, 0, 0.03);
    
    /* Colored Shadows - Soft */
    --shadow-primary: 0 4px 12px 0 rgba(0, 113, 227, 0.25);
    --shadow-success: 0 4px 12px 0 rgba(52, 199, 89, 0.25);
    --shadow-danger: 0 4px 12px 0 rgba(255, 59, 48, 0.25);
    
    /* Border Radius - Rounded and Friendly */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 20px;
    --radius-2xl: 28px;
    --radius-full: 9999px;
    
    /* Typography - SF Pro Style */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'SF Pro Text', 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    --font-family-mono: 'SF Mono', 'Fira Code', 'Fira Mono', 'Roboto Mono', monospace;
    
    /* Font Sizes - Apple Type Scale */
    --font-size-xs: 0.8125rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.0625rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.875rem;
    --font-size-4xl: 2.25rem;
    
    /* Font Weights - Apple Style */
    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;
    
    /* Line Heights - Generous */
    --line-height-tight: 1.2;
    --line-height-normal: 1.5;
    --line-height-relaxed: 1.6;
    
    /* Spacing - Apple Grid System */
    --spacing-0: 0;
    --spacing-1: 0.25rem;
    --spacing-2: 0.5rem;
    --spacing-3: 0.75rem;
    --spacing-4: 1rem;
    --spacing-5: 1.25rem;
    --spacing-6: 1.5rem;
    --spacing-8: 2rem;
    --spacing-10: 2.5rem;
    --spacing-12: 3rem;
    --spacing-16: 4rem;
    
    /* Transitions - Smooth and Natural */
    --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-normal: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    
    /* Z-Index Scale */
    --z-dropdown: 1000;
    --z-sticky: 1020;
    --z-fixed: 1030;
    --z-modal-backdrop: 1040;
    --z-modal: 1050;
    --z-popover: 1060;
    --z-tooltip: 1070;
}

body.dark {
    /* Dark Mode Colors - Apple Style */
    --color-text-primary: #f5f5f7;
    --color-text-secondary: #aeaeb2;
    --color-text-muted: #86868b;
    
    --color-bg-primary: #1c1c1e;
    --color-bg-secondary: #000000;
    --color-bg-tertiary: #2c2c2e;
    
    --color-border: #38383a;
    --color-border-light: #2c2c2e;
    --color-border-dark: #48484a;
    
    --color-gray-50: #2c2c2e;
    --color-gray-100: #3a3a3c;
    --color-gray-200: #48484a;
    --color-gray-700: #d1d1d6;
    --color-gray-800: #e5e5ea;
    --color-gray-900: #f5f5f7;
}

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

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: var(--line-height-normal);
    color: var(--color-text-primary);
    background-color: var(--color-bg-secondary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Button Component - Apple Style */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-2);
    padding: var(--spacing-3) var(--spacing-5);
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-medium);
    line-height: 1.4;
    text-decoration: none;
    border: 1px solid transparent;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
    white-space: nowrap;
    letter-spacing: -0.01em;
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

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

.btn-primary:hover:not(:disabled) {
    background: var(--color-primary-dark);
    box-shadow: var(--shadow-primary);
    transform: translateY(-1px);
}

.btn-primary:active:not(:disabled) {
    transform: translateY(0);
    box-shadow: var(--shadow-sm);
}

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

.btn-secondary:hover:not(:disabled) {
    background: var(--color-gray-100);
    border-color: var(--color-border-dark);
}

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

.btn-success:hover:not(:disabled) {
    background: var(--color-success-dark);
    box-shadow: var(--shadow-success);
    transform: translateY(-1px);
}

.btn-danger {
    background: var(--color-danger);
    color: var(--color-text-inverse);
}

.btn-danger:hover:not(:disabled) {
    background: var(--color-danger-dark);
    box-shadow: var(--shadow-danger);
    transform: translateY(-1px);
}

.btn-warning {
    background: var(--color-warning);
    color: var(--color-text-inverse);
}

.btn-warning:hover:not(:disabled) {
    background: var(--color-warning-dark);
    transform: translateY(-1px);
}

.btn-ghost {
    background: transparent;
    color: var(--color-text-secondary);
}

.btn-ghost:hover:not(:disabled) {
    background: var(--color-gray-100);
    color: var(--color-text-primary);
}

.btn-sm {
    padding: var(--spacing-2) var(--spacing-4);
    font-size: var(--font-size-sm);
}

.btn-lg {
    padding: var(--spacing-4) var(--spacing-6);
    font-size: var(--font-size-lg);
}

/* Card Component - Apple Style */
.card {
    background: var(--color-bg-primary);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--color-border-light);
    overflow: hidden;
    transition: all var(--transition-normal);
}

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

.card-header {
    padding: var(--spacing-5) var(--spacing-6);
    border-bottom: 1px solid var(--color-border-light);
    background: var(--color-bg-tertiary);
}

.card-title {
    font-size: var(--font-size-xl);
    font-weight: var(--font-weight-semibold);
    color: var(--color-text-primary);
    letter-spacing: -0.02em;
}

.card-body {
    padding: var(--spacing-6);
}

.card-footer {
    padding: var(--spacing-4) var(--spacing-6);
    border-top: 1px solid var(--color-border-light);
    background: var(--color-bg-tertiary);
}

/* Form Component - Apple Style */
.form-group {
    margin-bottom: var(--spacing-5);
}

.form-label {
    display: block;
    margin-bottom: var(--spacing-2);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--color-text-primary);
    letter-spacing: -0.01em;
}

.form-input,
.form-select,
.form-textarea {
    width: 100%;
    padding: var(--spacing-3) var(--spacing-4);
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: 1.5;
    color: var(--color-text-primary);
    background-color: var(--color-bg-primary);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
    letter-spacing: -0.01em;
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 4px rgba(0, 113, 227, 0.1);
}

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

.form-input-error {
    border-color: var(--color-danger);
}

.form-input-error:focus {
    box-shadow: 0 0 0 4px rgba(255, 59, 48, 0.1);
}

.form-error {
    margin-top: var(--spacing-2);
    font-size: var(--font-size-xs);
    color: var(--color-danger);
}

/* Table Component - Apple Style */
.table {
    width: 100%;
    border-collapse: collapse;
    font-size: var(--font-size-base);
}

.table th {
    padding: var(--spacing-4) var(--spacing-5);
    text-align: left;
    font-weight: var(--font-weight-semibold);
    color: var(--color-text-secondary);
    background: var(--color-bg-tertiary);
    border-bottom: 2px solid var(--color-border);
    white-space: nowrap;
    letter-spacing: -0.01em;
    font-size: var(--font-size-sm);
}

.table td {
    padding: var(--spacing-4) var(--spacing-5);
    border-bottom: 1px solid var(--color-border-light);
    vertical-align: middle;
}

.table tbody tr {
    transition: background-color var(--transition-fast);
}

.table tbody tr:hover {
    background: var(--color-gray-50);
}

body.dark .table tbody tr:hover {
    background: var(--color-gray-100);
}

/* Badge Component - Apple Style */
.badge {
    display: inline-flex;
    align-items: center;
    padding: var(--spacing-1) var(--spacing-3);
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-semibold);
    line-height: 1;
    border-radius: var(--radius-full);
    letter-spacing: 0.02em;
}

.badge-primary {
    background: var(--color-primary-100);
    color: var(--color-primary-dark);
}

.badge-success {
    background: var(--color-success-bg);
    color: var(--color-success-dark);
}

.badge-warning {
    background: var(--color-warning-bg);
    color: var(--color-warning-dark);
}

.badge-danger {
    background: var(--color-danger-bg);
    color: var(--color-danger-dark);
}

.badge-info {
    background: var(--color-info-bg);
    color: var(--color-info-dark);
}

/* Alert Component - Apple Style */
.alert {
    padding: var(--spacing-4) var(--spacing-5);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-4);
    border-left: 4px solid;
}

.alert-success {
    background: var(--color-success-bg);
    color: var(--color-success-dark);
    border-left-color: var(--color-success);
}

.alert-warning {
    background: var(--color-warning-bg);
    color: var(--color-warning-dark);
    border-left-color: var(--color-warning);
}

.alert-danger {
    background: var(--color-danger-bg);
    color: var(--color-danger-dark);
    border-left-color: var(--color-danger);
}

.alert-info {
    background: var(--color-info-bg);
    color: var(--color-info-dark);
    border-left-color: var(--color-info);
}

/* Modal Component - Apple Style */
.modal-backdrop {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.4);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    z-index: var(--z-modal-backdrop);
    animation: fadeIn var(--transition-normal);
}

.modal {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: var(--color-bg-primary);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-2xl);
    z-index: var(--z-modal);
    max-width: 90vw;
    max-height: 90vh;
    overflow: auto;
    animation: modalSlideUp var(--transition-normal);
}

.modal-header {
    padding: var(--spacing-5) var(--spacing-6);
    border-bottom: 1px solid var(--color-border-light);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.modal-title {
    font-size: var(--font-size-xl);
    font-weight: var(--font-weight-semibold);
    letter-spacing: -0.02em;
}

.modal-close {
    background: none;
    border: none;
    font-size: var(--font-size-2xl);
    color: var(--color-text-muted);
    cursor: pointer;
    padding: var(--spacing-2);
    line-height: 1;
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
}

.modal-close:hover {
    color: var(--color-text-primary);
    background: var(--color-gray-100);
}

.modal-body {
    padding: var(--spacing-6);
}

.modal-footer {
    padding: var(--spacing-4) var(--spacing-6);
    border-top: 1px solid var(--color-border-light);
    display: flex;
    justify-content: flex-end;
    gap: var(--spacing-3);
}

/* Tooltip Component - Apple Style */
.tooltip {
    position: relative;
}

.tooltip::after {
    content: attr(data-tooltip);
    position: absolute;
    bottom: 100%;
    left: 50%;
    transform: translateX(-50%) translateY(-8px);
    padding: var(--spacing-2) var(--spacing-3);
    background: var(--color-gray-800);
    color: var(--color-text-inverse);
    font-size: var(--font-size-xs);
    border-radius: var(--radius-sm);
    white-space: nowrap;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-fast);
    z-index: var(--z-tooltip);
    box-shadow: var(--shadow-md);
}

.tooltip:hover::after {
    opacity: 1;
    visibility: visible;
}

/* Loading Spinner - Apple Style */
.loading-spinner {
    display: inline-block;
    width: 24px;
    height: 24px;
    border: 3px solid var(--color-border);
    border-top-color: var(--color-primary);
    border-radius: 50%;
    animation: spin 0.8s cubic-bezier(0.4, 0, 0.2, 1) infinite;
}

/* Skeleton - Apple Style */
.skeleton {
    background: linear-gradient(
        90deg,
        var(--color-gray-200) 25%,
        var(--color-gray-100) 50%,
        var(--color-gray-200) 75%
    );
    background-size: 200% 100%;
    animation: shimmer 1.5s infinite;
    border-radius: var(--radius-md);
}

/* Animations - Apple Style */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes modalSlideUp {
    from {
        opacity: 0;
        transform: translate(-50%, -45%);
    }
    to {
        opacity: 1;
        transform: translate(-50%, -50%);
    }
}

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

@keyframes shimmer {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

.animate-pulse {
    animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}

/* Gradient Utilities - Apple Style */
.gradient-primary {
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-secondary) 100%);
}

.gradient-success {
    background: linear-gradient(135deg, var(--color-success) 0%, #14b8a6 100%);
}

.gradient-danger {
    background: linear-gradient(135deg, var(--color-danger) 0%, #f97316 100%);
}

.text-gradient {
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-secondary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Responsive Design - Apple Style */
@media (max-width: 768px) {
    :root {
        --font-size-base: 0.9375rem;
        --spacing-4: 0.875rem;
        --spacing-6: 1.25rem;
    }
    
    .modal {
        width: 95vw;
        margin: var(--spacing-4);
        border-radius: var(--radius-lg);
    }
    
    .table {
        display: block;
        overflow-x: auto;
        white-space: nowrap;
    }
}

@media (max-width: 480px) {
    :root {
        --font-size-base: 0.875rem;
    }
    
    .btn {
        padding: var(--spacing-3) var(--spacing-4);
    }
    
    .btn-lg {
        padding: var(--spacing-3) var(--spacing-5);
    }
}

/* Custom Scrollbar - Apple Style */
::-webkit-scrollbar {
    width: 10px;
    height: 10px;
}

::-webkit-scrollbar-track {
    background: var(--color-bg-tertiary);
    border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb {
    background: var(--color-gray-300);
    border-radius: var(--radius-full);
    border: 2px solid var(--color-bg-tertiary);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--color-gray-400);
}

body.dark ::-webkit-scrollbar-track {
    background: var(--color-gray-100);
}

body.dark ::-webkit-scrollbar-thumb {
    background: var(--color-gray-400);
    border-color: var(--color-gray-100);
}

/* Selection - Apple Style */
::selection {
    background: var(--color-primary-200);
    color: var(--color-primary-dark);
}

body.dark ::selection {
    background: var(--color-primary);
    color: var(--color-text-inverse);
}

/* Focus Styles - Apple Accessibility */
*:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

/* Print Styles */
@media print {
    body {
        background: white;
        color: black;
    }
    
    .btn,
    .modal-backdrop,
    .modal {
        display: none !important;
    }
}