/* Import Google Fonts */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500&display=swap');

/* CSS Variables for consistent theming */
:root {
    --primary-color: #2C5F85;
    --primary-light: #E8F4FD;
    --success-color: #28A745;
    --warning-color: #FD7E14;
    --neutral-color: #6C757D;
    --neutral-light: #ADB5BD;
    --text-primary: #212529;
    --text-secondary: #6C757D;
    --background-main: #FFFFFF;
    --background-light: #F8F9FA;
    --border-color: #DEE2E6;
    --shadow-light: 0 2px 4px rgba(0, 0, 0, 0.1);
    --shadow-medium: 0 4px 8px rgba(0, 0, 0, 0.15);
    --border-radius: 8px;
    --transition: all 0.3s ease;
}

/* Base styles */
body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    margin: 0;
    padding: 0;
    background: linear-gradient(135deg, var(--background-light) 0%, #E3F2FD 100%);
    color: var(--text-primary);
    min-height: 100vh;
}

/* TVPS Container */
.tvps-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 20px;
}

/* Header Section */
.tvps-header {
    background: var(--background-main);
    padding: 30px;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-light);
    margin-bottom: 20px;
    text-align: center;
}

.tvps-title {
    color: var(--primary-color);
    font-size: 2.5rem;
    font-weight: 700;
    margin: 0 0 20px 0;
    letter-spacing: -0.5px;
}

.progress-container {
    max-width: 600px;
    margin: 0 auto;
}

.progress {
    height: 12px;
    border-radius: 6px;
    background-color: var(--primary-light);
    margin-bottom: 10px;
}

.progress-bar {
    background: linear-gradient(90deg, var(--primary-color) 0%, var(--success-color) 100%);
    border-radius: 6px;
    transition: var(--transition);
}

.progress-text {
    color: var(--text-secondary);
    font-size: 0.9rem;
    font-weight: 500;
}

/* Navigation Tabs */
.tvps-nav {
    background: var(--background-main);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-light);
    margin-bottom: 20px;
    overflow-x: auto;
}

.tvps-tabs {
    border: none;
    padding: 15px 20px 0;
    flex-wrap: nowrap;
    min-width: max-content;
}

.tvps-tabs .nav-item {
    margin-right: 8px;
}

.tvps-tabs .nav-link {
    border: none;
    border-radius: var(--border-radius) var(--border-radius) 0 0;
    padding: 12px 20px;
    color: var(--text-secondary);
    background-color: var(--background-light);
    font-weight: 500;
    font-size: 0.9rem;
    transition: var(--transition);
    position: relative;
    display: flex;
    align-items: center;
    gap: 8px;
    white-space: nowrap;
    min-width: 100px;
    justify-content: center;
}

.tvps-tabs .nav-link:hover:not(.active):not(:disabled) {
    background-color: var(--primary-light);
    color: var(--primary-color);
    transform: translateY(-2px);
}

.tvps-tabs .nav-link.active {
    background-color: var(--primary-color);
    color: var(--background-main);
    box-shadow: var(--shadow-medium);
}

.tvps-tabs .nav-link:disabled {
    background-color: var(--neutral-light);
    color: var(--background-main);
    cursor: not-allowed;
}

.tab-icon {
    font-size: 1.1rem;
}

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

.tab-status {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    margin-left: 4px;
}

.tab-status.not-started {
    background-color: var(--neutral-light);
}

.tab-status.in-progress {
    background-color: var(--warning-color);
    animation: pulse 2s infinite;
}

.tab-status.completed {
    background-color: var(--success-color);
}

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

/* Content Cards */
.tvps-content {
    min-height: 600px;
}

.content-card {
    background: var(--background-main);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-light);
    overflow: hidden;
}

.content-card .card-header {
    background: linear-gradient(135deg, var(--primary-color) 0%, #1e4a66 100%);
    color: var(--background-main);
    padding: 25px 30px;
    border-bottom: none;
}

.section-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin: 0 0 8px 0;
}

.section-description {
    margin: 0;
    opacity: 0.9;
    font-size: 0.95rem;
}

.content-card .card-body {
    padding: 30px;
}

.content-card .card-footer {
    background-color: var(--background-light);
    padding: 20px 30px;
    border-top: 1px solid var(--border-color);
}

/* Form Elements */
.form-group {
    margin-bottom: 25px;
}

.form-label {
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 8px;
    display: block;
    font-size: 0.95rem;
}

.form-control {
    width: 100%;
    padding: 12px 16px;
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 1rem;
    transition: var(--transition);
    background-color: var(--background-main);
}

.form-control:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(44, 95, 133, 0.1);
    outline: none;
}

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

/* Question Sections */
.examples-section {
    background: linear-gradient(135deg, #E8F5E8 0%, #F0F8F0 100%);
    padding: 20px;
    border-radius: var(--border-radius);
    margin-bottom: 30px;
    border-left: 4px solid var(--success-color);
}

.examples-title {
    color: var(--success-color);
    font-size: 1.1rem;
    font-weight: 600;
    margin: 0 0 15px 0;
}

.questions-section {
    background-color: var(--background-light);
    padding: 20px;
    border-radius: var(--border-radius);
}

.questions-title {
    color: var(--primary-color);
    font-size: 1.1rem;
    font-weight: 600;
    margin: 0 0 20px 0;
}

.questions-grid {
    display: grid;
    gap: 15px;
}

.question-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 0;
    border-bottom: 1px solid var(--border-color);
}

.question-item:last-child {
    border-bottom: none;
}

.example-item {
    background-color: rgba(255, 255, 255, 0.7);
    padding: 15px;
    border-radius: var(--border-radius);
    margin-bottom: 10px;
    border-bottom: none;
}

.question-label {
    font-weight: 600;
    color: var(--text-primary);
    min-width: 60px;
    font-family: 'JetBrains Mono', monospace;
}

.answer-group {
    display: flex;
    gap: 5px;
}

.answer-btn {
    min-width: 40px;
    padding: 8px 12px;
    border: 2px solid var(--border-color);
    background-color: var(--background-main);
    color: var(--text-primary);
    font-weight: 600;
    transition: var(--transition);
    border-radius: var(--border-radius);
}

.answer-btn:hover {
    border-color: var(--primary-color);
    background-color: var(--primary-light);
    transform: translateY(-1px);
}

.btn-check:checked + .answer-btn {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
    color: var(--background-main);
    box-shadow: var(--shadow-medium);
}

/* Navigation Buttons */
.navigation-buttons {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.btn {
    padding: 12px 24px;
    border-radius: var(--border-radius);
    font-weight: 600;
    font-size: 0.9rem;
    transition: var(--transition);
    border: none;
    cursor: pointer;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

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

.btn-primary:hover {
    background-color: #1e4a66;
    transform: translateY(-2px);
    box-shadow: var(--shadow-medium);
}

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

.btn-success:hover {
    background-color: #1e7e34;
    transform: translateY(-2px);
    box-shadow: var(--shadow-medium);
}

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

.btn-secondary:hover {
    background-color: #5a6268;
    transform: translateY(-2px);
}

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

.btn-outline-secondary:hover {
    background-color: var(--neutral-color);
    color: var(--background-main);
}

/* Results Section */
#results-content {
    min-height: 200px;
    /* display: flex; */ /* Removed to allow natural block stacking */
    /* flex-direction: column; */ /* This would also work if display:flex is kept */
    /* align-items: stretch; */ /* Ensure cards take full width if flex is used */
}

/* If a placeholder message is shown, center it */
#results-content > p.text-muted {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 200px; /* Same as #results-content min-height */
    width: 100%;
}


/* Responsive Design */
@media (max-width: 1200px) {
    .tvps-container {
        padding: 15px;
    }
    
    .tvps-title {
        font-size: 2rem;
    }
}

@media (max-width: 768px) {
    .tvps-container {
        padding: 10px;
    }
    
    .tvps-title {
        font-size: 1.5rem;
    }
    
    .tvps-header {
        padding: 20px 15px;
    }
    
    .content-card .card-header,
    .content-card .card-body,
    .content-card .card-footer {
        padding: 20px 15px;
    }
    
    .tvps-tabs {
        padding: 10px;
        overflow-x: auto;
    }
    
    .tvps-tabs .nav-link {
        min-width: 80px;
        padding: 10px 15px;
        font-size: 0.8rem;
    }
    
    .question-item {
        flex-direction: column;
        align-items: flex-start;
        gap: 10px;
    }
    
    .answer-group {
        width: 100%;
    }
    
    .navigation-buttons {
        flex-direction: column;
        gap: 15px;
    }
    
    .navigation-buttons > div:first-child {
        order: 2;
    }
    
    .navigation-buttons > .btn-next {
        order: 1;
        width: 100%;
    }
}

@media (max-width: 480px) {
    .answer-btn {
        min-width: 35px;
        padding: 6px 8px;
        font-size: 0.8rem;
    }
    
    .question-label {
        min-width: 50px;
        font-size: 0.9rem;
    }
}

/* Utility classes */
.hidden {
    display: none !important;
}

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

.text-muted {
    color: var(--text-secondary);
}

.mb-4 {
    margin-bottom: 1.5rem;
}

.mt-4 {
    margin-top: 1.5rem;
}

.me-2 {
    margin-right: 0.5rem;
}

.ms-2 {
    margin-left: 0.5rem;
}

.d-none {
    display: none;
}

/* Loading Spinner */
.spinner-border {
    width: 1.5rem;
    height: 1.5rem;
    border: 0.2em solid currentColor;
    border-right-color: transparent;
    border-radius: 50%;
    animation: spinner-border 0.75s linear infinite;
}

@keyframes spinner-border {
    to {
        transform: rotate(360deg);
    }
}