/* CSS Variables */
:root {
    --color-primary: #05386B;
    --color-secondary: #379683;
    --color-accent: #5CDB95;
    --color-light-accent: #8EE4AF;
    --color-background: #EDF5E1;
    --color-white: #ffffff;
    --color-text-dark: #2c3e50;
    --color-text-light: #7f8c8d;
    --color-success: #27ae60;
    --color-warning: #f39c12;
    --color-danger: #e74c3c;
    
    --font-family-primary: 'Segoe UI', Tahoma, Geneva, Verdana, 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: 2rem;
    
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    
    --border-radius-sm: 0.375rem;
    --border-radius-md: 0.5rem;
    --border-radius-lg: 0.75rem;
    --border-radius-xl: 1rem;
    
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
    
    --transition-fast: 0.15s ease-in-out;
    --transition-normal: 0.3s ease-in-out;
    --transition-slow: 0.5s ease-in-out;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family-primary);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--color-text-dark);
    background-color: var(--color-background);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* Header */
.header {
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-secondary) 100%);
    color: var(--color-white);
    padding: var(--spacing-xl) 0;
    text-align: center;
    box-shadow: var(--shadow-md);
}

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

.header__title {
    font-size: var(--font-size-3xl);
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
}

.header__icon {
    font-size: 2.5rem;
}

.header__subtitle {
    font-size: var(--font-size-lg);
    opacity: 0.9;
    font-weight: 300;
}

/* Main Content */
.main {
    flex: 1;
    padding: var(--spacing-2xl) 0;
}

/* Welcome Section */
.welcome {
    text-align: center;
    max-width: 800px;
    margin: 0 auto var(--spacing-2xl);
}

.welcome__title {
    font-size: var(--font-size-3xl);
    color: var(--color-primary);
    margin-bottom: var(--spacing-lg);
    font-weight: 600;
}

.welcome__description {
    font-size: var(--font-size-lg);
    color: var(--color-text-light);
    margin-bottom: var(--spacing-2xl);
    line-height: 1.7;
}

.welcome__stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-2xl);
}

.stat {
    background: var(--color-white);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-sm);
    border: 2px solid var(--color-light-accent);
    transition: transform var(--transition-normal);
}

.stat:hover {
    transform: translateY(-2px);
}

.stat__number {
    display: block;
    font-size: var(--font-size-2xl);
    font-weight: 700;
    color: var(--color-accent);
}

.stat__label {
    font-size: var(--font-size-sm);
    color: var(--color-text-light);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-sm) var(--spacing-lg);
    border: none;
    border-radius: var(--border-radius-md);
    font-size: var(--font-size-base);
    font-weight: 500;
    text-decoration: none;
    cursor: pointer;
    transition: all var(--transition-normal);
    min-height: 44px;
}

.btn--primary {
    background: linear-gradient(135deg, var(--color-accent) 0%, var(--color-secondary) 100%);
    color: var(--color-white);
}

.btn--primary:hover {
    transform: translateY(-1px);
    box-shadow: var(--shadow-lg);
}

.btn--secondary {
    background: var(--color-white);
    color: var(--color-primary);
    border: 2px solid var(--color-primary);
}

.btn--secondary:hover {
    background: var(--color-primary);
    color: var(--color-white);
}

.btn--large {
    padding: var(--spacing-md) var(--spacing-2xl);
    font-size: var(--font-size-lg);
}

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

.btn:disabled:hover {
    transform: none;
    box-shadow: none;
}

/* Questionnaire */
.questionnaire {
    max-width: 700px;
    margin: 0 auto;
    background: var(--color-white);
    border-radius: var(--border-radius-xl);
    padding: var(--spacing-2xl);
    box-shadow: var(--shadow-lg);
}

.questionnaire__header {
    text-align: center;
    margin-bottom: var(--spacing-2xl);
}

.questionnaire__title {
    font-size: var(--font-size-2xl);
    color: var(--color-primary);
    margin-bottom: var(--spacing-lg);
}

.progress-bar {
    width: 100%;
    height: 8px;
    background: #e0e6ed;
    border-radius: var(--border-radius-sm);
    overflow: hidden;
    margin-bottom: var(--spacing-sm);
}

.progress-bar__fill {
    height: 100%;
    background: linear-gradient(90deg, var(--color-accent) 0%, var(--color-secondary) 100%);
    border-radius: var(--border-radius-sm);
    transition: width var(--transition-normal);
    width: 0%;
}

.progress-text {
    font-size: var(--font-size-sm);
    color: var(--color-text-light);
}

.question-container {
    margin-bottom: var(--spacing-2xl);
}

.question {
    margin-bottom: var(--spacing-xl);
}

.question__title {
    font-size: var(--font-size-lg);
    color: var(--color-primary);
    margin-bottom: var(--spacing-md);
    font-weight: 500;
}

.question__options {
    display: grid;
    gap: var(--spacing-sm);
}

.option {
    display: flex;
    align-items: center;
    padding: var(--spacing-md);
    background: #f8f9fa;
    border: 2px solid transparent;
    border-radius: var(--border-radius-md);
    cursor: pointer;
    transition: all var(--transition-normal);
}

.option:hover {
    background: var(--color-light-accent);
    border-color: var(--color-accent);
}

.option--selected {
    background: var(--color-accent);
    color: var(--color-white);
    border-color: var(--color-secondary);
}

.option__input {
    margin-right: var(--spacing-sm);
}

.option__label {
    flex: 1;
    cursor: pointer;
}

.input-field {
    width: 100%;
    padding: var(--spacing-md);
    border: 2px solid #e0e6ed;
    border-radius: var(--border-radius-md);
    font-size: var(--font-size-base);
    transition: border-color var(--transition-normal);
}

.input-field:focus {
    outline: none;
    border-color: var(--color-accent);
}

.questionnaire__navigation {
    display: flex;
    justify-content: space-between;
    gap: var(--spacing-md);
}

/* Results Section */
.results {
    max-width: 1000px;
    margin: 0 auto;
}

.results__header {
    text-align: center;
    margin-bottom: var(--spacing-2xl);
}

.results__title {
    font-size: var(--font-size-3xl);
    color: var(--color-primary);
    margin-bottom: var(--spacing-md);
}

.results__subtitle {
    font-size: var(--font-size-lg);
    color: var(--color-text-light);
}

.results__grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-2xl);
}

/* Cards */
.card {
    background: var(--color-white);
    border-radius: var(--border-radius-xl);
    padding: var(--spacing-xl);
    box-shadow: var(--shadow-md);
    transition: transform var(--transition-normal);
}

.card:hover {
    transform: translateY(-2px);
}

.card--highlight {
    background: linear-gradient(135deg, var(--color-accent) 0%, var(--color-light-accent) 100%);
    color: var(--color-white);
}

.card__header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--spacing-lg);
}

.card__title {
    font-size: var(--font-size-xl);
    font-weight: 600;
}

.card__icon {
    font-size: var(--font-size-2xl);
}

/* Life Expectancy */
.life-expectancy {
    text-align: center;
    margin-bottom: var(--spacing-lg);
}

.life-expectancy__number {
    font-size: 4rem;
    font-weight: 700;
    display: block;
}

.life-expectancy__label {
    font-size: var(--font-size-lg);
    opacity: 0.9;
}

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

.life-remaining__text {
    display: block;
    margin-bottom: var(--spacing-xs);
    opacity: 0.9;
}

.life-remaining__years {
    font-size: var(--font-size-2xl);
    font-weight: 600;
    margin: 0 var(--spacing-xs);
}

/* Health Score */
.health-score {
    text-align: center;
}

.score-circle {
    width: 120px;
    height: 120px;
    border-radius: 50%;
    background: conic-gradient(var(--color-accent) 0deg, var(--color-accent) calc(var(--score, 75) * 3.6deg), #e0e6ed calc(var(--score, 75) * 3.6deg));
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    margin: 0 auto var(--spacing-md);
    position: relative;
}

.score-circle::before {
    content: '';
    position: absolute;
    inset: 15px;
    background: var(--color-white);
    border-radius: 50%;
}

.score-number {
    font-size: var(--font-size-2xl);
    font-weight: 700;
    color: var(--color-primary);
    z-index: 1;
}

.score-label {
    font-size: var(--font-size-sm);
    color: var(--color-text-light);
    z-index: 1;
}

.score-description {
    color: var(--color-text-light);
}

/* Comparison */
.comparison__text {
    margin-bottom: var(--spacing-md);
    color: var(--color-text-dark);
}

.comparison__bar {
    width: 100%;
    height: 20px;
    background: #e0e6ed;
    border-radius: var(--border-radius-sm);
    overflow: hidden;
}

.comparison__fill {
    height: 100%;
    background: linear-gradient(90deg, var(--color-accent) 0%, var(--color-secondary) 100%);
    border-radius: var(--border-radius-sm);
    transition: width var(--transition-slow);
}

/* Timeline */
.timeline-container {
    margin: var(--spacing-2xl) 0;
    background: var(--color-white);
    border-radius: var(--border-radius-xl);
    padding: var(--spacing-xl);
    box-shadow: var(--shadow-md);
}

.timeline__title {
    font-size: var(--font-size-xl);
    color: var(--color-primary);
    margin-bottom: var(--spacing-lg);
    text-align: center;
}

.timeline {
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: relative;
    padding: var(--spacing-lg) 0;
    overflow-x: auto;
}

.timeline::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--color-accent) 0%, var(--color-secondary) 100%);
    border-radius: 2px;
}

.timeline__milestone {
    background: var(--color-white);
    border: 4px solid var(--color-accent);
    border-radius: 50%;
    width: 60px;
    height: 60px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    position: relative;
    z-index: 1;
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--color-primary);
    text-align: center;
    min-width: 60px;
}

.timeline__milestone--current {
    border-color: var(--color-secondary);
    background: var(--color-secondary);
    color: var(--color-white);
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.1); }
    100% { transform: scale(1); }
}

/* Tips and Challenges */
.tips-challenges {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: var(--spacing-xl);
    margin: var(--spacing-2xl) 0;
}

.tips, .challenges {
    background: var(--color-white);
    border-radius: var(--border-radius-xl);
    padding: var(--spacing-xl);
    box-shadow: var(--shadow-md);
}

.tips__title, .challenges__title {
    font-size: var(--font-size-xl);
    color: var(--color-primary);
    margin-bottom: var(--spacing-lg);
}

.tip-item, .challenge-item {
    background: #f8f9fa;
    border-left: 4px solid var(--color-accent);
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-md);
    border-radius: var(--border-radius-md);
    transition: transform var(--transition-normal);
}

.tip-item:hover, .challenge-item:hover {
    transform: translateX(4px);
}

.tip-item__title, .challenge-item__title {
    font-weight: 600;
    color: var(--color-primary);
    margin-bottom: var(--spacing-xs);
}

.tip-item__description, .challenge-item__description {
    color: var(--color-text-light);
    font-size: var(--font-size-sm);
}

.challenge-item__reward {
    color: var(--color-accent);
    font-weight: 600;
    font-size: var(--font-size-sm);
    margin-top: var(--spacing-xs);
}

/* Results Actions */
.results__actions {
    display: flex;
    justify-content: center;
    gap: var(--spacing-md);
    margin-top: var(--spacing-2xl);
}

/* Alerts */
.alerts {
    position: fixed;
    top: var(--spacing-lg);
    right: var(--spacing-lg);
    z-index: 1000;
    max-width: 400px;
}

.alert {
    background: var(--color-white);
    border-radius: var(--border-radius-md);
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-sm);
    box-shadow: var(--shadow-lg);
    border-left: 4px solid;
    animation: slideIn 0.3s ease-out;
}

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

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

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

.alert__title {
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
}

.alert__message {
    font-size: var(--font-size-sm);
    color: var(--color-text-light);
}

@keyframes slideIn {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

/* Loading Overlay */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(5, 56, 107, 0.9);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
}

.loading-spinner {
    text-align: center;
    color: var(--color-white);
}

.spinner {
    width: 60px;
    height: 60px;
    border: 4px solid rgba(255, 255, 255, 0.3);
    border-top: 4px solid var(--color-accent);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto var(--spacing-lg);
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.loading-text {
    font-size: var(--font-size-lg);
}

/* Footer */
.footer {
    background: var(--color-primary);
    color: var(--color-white);
    padding: var(--spacing-lg) 0;
    text-align: center;
    margin-top: auto;
}

.footer__text {
    font-size: var(--font-size-sm);
    opacity: 0.9;
}

.footer__link {
    color: var(--color-accent);
    text-decoration: none;
    transition: color var(--transition-normal);
}

.footer__link:hover {
    color: var(--color-light-accent);
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 0 var(--spacing-sm);
    }
    
    .header__title {
        font-size: var(--font-size-2xl);
    }
    
    .welcome__title {
        font-size: var(--font-size-2xl);
    }
    
    .welcome__stats {
        grid-template-columns: 1fr;
    }
    
    .results__grid {
        grid-template-columns: 1fr;
    }
    
    .tips-challenges {
        grid-template-columns: 1fr;
    }
    
    .questionnaire {
        padding: var(--spacing-lg);
    }
    
    .questionnaire__navigation {
        flex-direction: column;
    }
    
    .results__actions {
        flex-direction: column;
        align-items: center;
    }
    
    .timeline {
        flex-direction: column;
        gap: var(--spacing-md);
    }
    
    .timeline::before {
        display: none;
    }
    
    .alerts {
        left: var(--spacing-sm);
        right: var(--spacing-sm);
        max-width: none;
    }
}

@media (max-width: 480px) {
    .header {
        padding: var(--spacing-lg) 0;
    }
    
    .header__title {
        font-size: var(--font-size-xl);
        flex-direction: column;
        gap: var(--spacing-xs);
    }
    
    .header__icon {
        font-size: 2rem;
    }
    
    .main {
        padding: var(--spacing-lg) 0;
    }
    
    .life-expectancy__number {
        font-size: 3rem;
    }
    
    .score-circle {
        width: 100px;
        height: 100px;
    }
    
    .btn--large {
        padding: var(--spacing-md) var(--spacing-lg);
        font-size: var(--font-size-base);
    }
}

/* Accessibility */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* Focus styles for accessibility */
.btn:focus,
.input-field:focus,
.option:focus {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    :root {
        --color-text-light: var(--color-text-dark);
    }
}