/* ===================================
   CSS Variables & Design Tokens
   =================================== */
:root {
    /* Colors - Modern neutral palette */
    --color-primary: #2563eb;
    --color-primary-hover: #1d4ed8;
    --color-primary-light: #eff6ff;
    
    --color-success: #059669;
    --color-success-light: #ecfdf5;
    --color-warning: #d97706;
    --color-warning-light: #fffbeb;
    --color-error: #dc2626;
    --color-error-light: #fef2f2;
    
    /* Grays */
    --color-gray-50: #f9fafb;
    --color-gray-100: #f3f4f6;
    --color-gray-200: #e5e7eb;
    --color-gray-300: #d1d5db;
    --color-gray-400: #9ca3af;
    --color-gray-500: #6b7280;
    --color-gray-600: #4b5563;
    --color-gray-700: #374151;
    --color-gray-800: #1f2937;
    --color-gray-900: #111827;
    
    /* Background */
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-tertiary: #f3f4f6;
    
    /* Text */
    --text-primary: #111827;
    --text-secondary: #4b5563;
    --text-tertiary: #6b7280;
    --text-inverse: #ffffff;
    
    /* Borders */
    --border-color: #e5e7eb;
    --border-color-focus: #2563eb;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
    
    /* Spacing */
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-2xl: 3rem;
    --space-3xl: 4rem;
    
    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-full: 9999px;
    
    /* Typography */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.875rem;
    --font-size-4xl: 2.25rem;
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 200ms ease;
    --transition-slow: 300ms ease;
    
    /* Container */
    --container-max: 1200px;
}

/* ===================================
   Reset & Base Styles
   =================================== */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-secondary);
    min-height: 100vh;
}

/* ===================================
   Layout
   =================================== */
.container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: var(--space-lg);
}

.hidden {
    display: none !important;
}

/* ===================================
   Header
   =================================== */
.header {
    text-align: center;
    padding: var(--space-2xl) 0;
}

.header-title {
    font-size: var(--font-size-3xl);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--space-sm);
    letter-spacing: -0.02em;
}

.header-subtitle {
    font-size: var(--font-size-lg);
    color: var(--text-secondary);
    font-weight: 400;
}

/* ===================================
   Cards
   =================================== */
.card {
    background: var(--bg-primary);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-md);
    padding: var(--space-xl);
    margin-bottom: var(--space-lg);
    border: 1px solid var(--border-color);
}

.card-title {
    font-size: var(--font-size-xl);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--space-sm);
}

.card-description {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    margin-bottom: var(--space-lg);
}

/* ===================================
   Form Styles
   =================================== */
.form {
    display: flex;
    flex-direction: column;
    gap: var(--space-lg);
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-lg);
}

@media (max-width: 640px) {
    .form-row {
        grid-template-columns: 1fr;
    }
}

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

.form-label {
    font-size: var(--font-size-sm);
    font-weight: 500;
    color: var(--text-primary);
}

.form-input {
    width: 100%;
    padding: var(--space-md);
    font-size: var(--font-size-base);
    font-family: var(--font-family);
    color: var(--text-primary);
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

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

.form-input:hover {
    border-color: var(--color-gray-400);
}

.form-input:focus {
    outline: none;
    border-color: var(--border-color-focus);
    box-shadow: 0 0 0 3px var(--color-primary-light);
}

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

.form-input.error:focus {
    box-shadow: 0 0 0 3px var(--color-error-light);
}

.form-error {
    font-size: var(--font-size-xs);
    color: var(--color-error);
    min-height: 1rem;
}

/* Checkbox Styles */
.form-group-checkbox {
    margin-top: var(--space-sm);
}

.checkbox-label {
    display: flex;
    align-items: flex-start;
    gap: var(--space-md);
    cursor: pointer;
    user-select: none;
}

.form-checkbox {
    position: absolute;
    opacity: 0;
    width: 0;
    height: 0;
}

.checkbox-custom {
    flex-shrink: 0;
    width: 20px;
    height: 20px;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-sm);
    background: var(--bg-primary);
    transition: all var(--transition-fast);
    position: relative;
    margin-top: 2px;
}

.form-checkbox:checked + .checkbox-custom {
    background: var(--color-primary);
    border-color: var(--color-primary);
}

.form-checkbox:checked + .checkbox-custom::after {
    content: '';
    position: absolute;
    left: 6px;
    top: 2px;
    width: 5px;
    height: 10px;
    border: solid white;
    border-width: 0 2px 2px 0;
    transform: rotate(45deg);
}

.form-checkbox:focus + .checkbox-custom {
    box-shadow: 0 0 0 3px var(--color-primary-light);
}

.checkbox-label:hover .checkbox-custom {
    border-color: var(--color-primary);
}

.checkbox-text {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    line-height: 1.5;
}

.form-group-checkbox .form-error {
    margin-left: calc(20px + var(--space-md));
}

/* ===================================
   Buttons
   =================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
    padding: var(--space-md) var(--space-xl);
    font-size: var(--font-size-base);
    font-weight: 500;
    font-family: var(--font-family);
    border-radius: var(--radius-md);
    border: none;
    cursor: pointer;
    transition: all var(--transition-fast);
    text-decoration: none;
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

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

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

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

.btn-secondary:hover:not(:disabled) {
    background: var(--color-gray-200);
}

.btn-outline {
    background: transparent;
    color: var(--color-primary);
    border: 1px solid var(--color-primary);
}

.btn-outline:hover:not(:disabled) {
    background: var(--color-primary-light);
}

.btn-bold {
    font-weight: 700;
    padding: var(--space-md) var(--space-xl);
    font-size: var(--font-size-base);
    letter-spacing: 0.01em;
    box-shadow: var(--shadow-md);
}

.btn-bold:hover:not(:disabled) {
    box-shadow: var(--shadow-lg);
    transform: translateY(-1px);
}

/* Button Loading State */
.btn.loading .btn-text {
    visibility: hidden;
}

.btn.loading .btn-loader {
    position: absolute;
}

.btn-loader {
    display: none;
    width: 20px;
    height: 20px;
    border: 2px solid transparent;
    border-top-color: currentColor;
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

.btn.loading .btn-loader {
    display: block;
}

.btn.loading {
    position: relative;
}

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

/* ===================================
   Loading Section
   =================================== */
.loading-card {
    text-align: center;
    padding: var(--space-3xl);
}

.loading-content {
    max-width: 400px;
    margin: 0 auto;
}

.loading-spinner {
    width: 48px;
    height: 48px;
    border: 3px solid var(--color-gray-200);
    border-top-color: var(--color-primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto var(--space-lg);
}

.loading-title {
    font-size: var(--font-size-xl);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--space-sm);
}

.loading-description {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    margin-bottom: var(--space-xl);
}

.loading-steps {
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
    text-align: left;
}

.loading-step {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    padding: var(--space-sm);
    border-radius: var(--radius-md);
    opacity: 0.4;
    transition: opacity var(--transition-base);
}

.loading-step.active {
    opacity: 1;
    background: var(--color-primary-light);
}

.loading-step.complete {
    opacity: 1;
}

.step-icon {
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: var(--color-gray-200);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    position: relative;
}

.loading-step.active .step-icon {
    background: var(--color-primary);
}

.loading-step.active .step-icon::after {
    content: '';
    width: 8px;
    height: 8px;
    background: white;
    border-radius: 50%;
    animation: pulse 1s ease-in-out infinite;
}

.loading-step.complete .step-icon {
    background: var(--color-success);
}

.loading-step.complete .step-icon::after {
    content: '';
    width: 10px;
    height: 6px;
    border: 2px solid white;
    border-top: none;
    border-right: none;
    transform: rotate(-45deg);
    margin-top: -2px;
}

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

.loading-step.active .step-text,
.loading-step.complete .step-text {
    color: var(--text-primary);
    font-weight: 500;
}

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

/* ===================================
   Error Section
   =================================== */
.error-card {
    text-align: center;
    padding: var(--space-3xl);
}

.error-content {
    max-width: 400px;
    margin: 0 auto;
}

.error-icon {
    width: 64px;
    height: 64px;
    background: var(--color-error-light);
    color: var(--color-error);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--font-size-2xl);
    font-weight: 700;
    margin: 0 auto var(--space-lg);
}

.error-title {
    font-size: var(--font-size-xl);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--space-sm);
}

.error-description {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    margin-bottom: var(--space-xl);
}

/* ===================================
   Report Header
   =================================== */
.report-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--space-lg);
}

.report-title {
    font-size: var(--font-size-2xl);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--space-xs);
}

.report-meta {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
}

.report-header-actions {
    display: flex;
    gap: var(--space-md);
    align-items: center;
    flex-wrap: wrap;
}

/* ===================================
   Grade Cards
   =================================== */
.grade-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
    gap: var(--space-lg);
    margin-bottom: var(--space-lg);
}

.grade-card {
    display: flex;
    flex-direction: column;
}

.grade-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--space-lg);
    padding-bottom: var(--space-md);
    border-bottom: 1px solid var(--border-color);
}

.grade-title {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--text-primary);
}

.grade-badge {
    font-size: var(--font-size-xl);
    font-weight: 700;
    padding: var(--space-sm) var(--space-md);
    border-radius: var(--radius-md);
    background: var(--color-gray-100);
    color: var(--text-primary);
    min-width: 48px;
    text-align: center;
}

.grade-badge.grade-a { background: #dcfce7; color: #166534; }
.grade-badge.grade-b { background: #dbeafe; color: #1e40af; }
.grade-badge.grade-c { background: #fef9c3; color: #854d0e; }
.grade-badge.grade-d { background: #fed7aa; color: #9a3412; }
.grade-badge.grade-f { background: #fecaca; color: #991b1b; }

.grade-content {
    flex: 1;
}

.grade-section {
    margin-bottom: var(--space-lg);
}

.grade-section:last-child {
    margin-bottom: 0;
}

.section-title {
    font-size: var(--font-size-sm);
    font-weight: 600;
    margin-bottom: var(--space-sm);
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.section-title::before {
    content: '';
    width: 8px;
    height: 8px;
    border-radius: 50%;
    flex-shrink: 0;
}

.section-title.positive::before { background: var(--color-success); }
.section-title.negative::before { background: var(--color-error); }
.section-title.neutral::before { background: var(--color-primary); }

.section-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.section-list li {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    padding-left: var(--space-lg);
    position: relative;
    line-height: 1.5;
}

.section-list li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 8px;
    width: 6px;
    height: 6px;
    background: var(--color-gray-300);
    border-radius: 50%;
}

.section-text {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    line-height: 1.6;
}

/* ===================================
   Summary Table
   =================================== */
.summary-card {
    overflow: hidden;
}

.summary-title {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--space-lg);
}

.summary-table {
    width: 100%;
    border-collapse: collapse;
    font-size: var(--font-size-sm);
}

.summary-table th,
.summary-table td {
    padding: var(--space-md);
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.summary-table th {
    background: var(--bg-tertiary);
    font-weight: 600;
    color: var(--text-primary);
}

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

.summary-table tr:last-child td {
    border-bottom: none;
}

.summary-table .grade-cell {
    font-weight: 600;
}

.summary-table .grade-cell.grade-a { color: #166534; }
.summary-table .grade-cell.grade-b { color: #1e40af; }
.summary-table .grade-cell.grade-c { color: #854d0e; }
.summary-table .grade-cell.grade-d { color: #9a3412; }
.summary-table .grade-cell.grade-f { color: #991b1b; }

/* ===================================
   Recommendations
   =================================== */
.recommendations-title {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--space-lg);
}

.recommendations-section {
    margin-bottom: var(--space-xl);
}

.recommendations-subtitle {
    font-size: var(--font-size-base);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--space-md);
    padding-bottom: var(--space-sm);
    border-bottom: 2px solid var(--color-primary);
    display: inline-block;
}

.recommendations-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
}

.recommendations-list li {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    padding: var(--space-md);
    background: var(--bg-tertiary);
    border-radius: var(--radius-md);
    border-left: 3px solid var(--color-primary);
    line-height: 1.6;
}

.recommendations-cta {
    margin-top: var(--space-xl);
    padding-top: var(--space-xl);
    border-top: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: var(--space-md);
}

.cta-text {
    font-size: var(--font-size-base);
    color: var(--text-primary);
    font-weight: 500;
}

.cta-buttons {
    display: flex;
    gap: var(--space-md);
    align-items: center;
    flex-wrap: wrap;
}

/* ===================================
   Footer
   =================================== */
.footer {
    text-align: center;
    padding: var(--space-xl) 0;
    color: var(--text-tertiary);
    font-size: var(--font-size-sm);
}

/* Hidden Admin Link */
.admin-link {
    position: fixed;
    bottom: 8px;
    right: 10px;
    color: var(--text-tertiary);
    text-decoration: none;
    font-size: 10px;
    opacity: 0.4;
    transition: opacity 0.3s ease;
    z-index: 10;
    cursor: default;
    user-select: none;
}

.admin-link:hover {
    opacity: 0.4;
    cursor: pointer;
}

/* ===================================
   Animations
   =================================== */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.card {
    animation: fadeIn var(--transition-slow) ease-out;
}

/* ===================================
   Print Styles
   =================================== */
@media print {
    body {
        background: white;
        -webkit-print-color-adjust: exact;
        print-color-adjust: exact;
    }
    
    .container {
        max-width: 100%;
        padding: 0;
    }
    
    .card {
        box-shadow: none;
        border: 1px solid var(--border-color);
        break-inside: avoid;
        page-break-inside: avoid;
        margin-bottom: var(--space-md);
    }
    
    .btn,
    .report-header-actions,
    .cta-buttons,
    .recommendations-cta {
        display: none !important;
    }
    
    .header,
    .header-subtitle,
    .footer,
    #form-section,
    #loading-section,
    #error-section {
        display: none !important;
    }
    
    #report-section {
        display: block !important;
    }
    
    .report-header {
        border-bottom: 2px solid var(--color-primary);
        padding-bottom: var(--space-md);
    }
    
    .report-title {
        font-size: var(--font-size-2xl);
    }
    
    .grade-cards {
        display: grid;
        grid-template-columns: 1fr;
        gap: var(--space-md);
    }
    
    .grade-badge {
        -webkit-print-color-adjust: exact;
        print-color-adjust: exact;
    }
    
    .summary-table {
        font-size: var(--font-size-sm);
    }
    
    .recommendations-list li {
        -webkit-print-color-adjust: exact;
        print-color-adjust: exact;
    }
}

/* ===================================
   Responsive Adjustments
   =================================== */
@media (max-width: 768px) {
    .container {
        padding: var(--space-md);
    }
    
    .header {
        padding: var(--space-xl) 0;
    }
    
    .header-title {
        font-size: var(--font-size-2xl);
    }
    
    .card {
        padding: var(--space-lg);
    }
    
    .grade-cards {
        grid-template-columns: 1fr;
    }
    
    .report-header {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .summary-table {
        font-size: var(--font-size-xs);
    }
    
    .recommendations-cta {
        flex-direction: column;
        text-align: center;
    }
}