/* CSS Variables for consistent theming */
:root {
    --primary-color: #7868E6;
    --secondary-color: #B8B5FF;
    --accent-color: #FFB4B4;
    --background-color: #EDEEF7;
    --light-blue: #E4FBFF;
    --white: #FFFFFF;
    --text-dark: #333333;
    --text-light: #666666;
    --border-color: #E0E0E0;
    --shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    --shadow-hover: 0 4px 20px rgba(0, 0, 0, 0.15);
    --border-radius: 12px;
    --transition: all 0.3s ease;
    --font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

/* Reset and base styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: var(--font-family);
    background-color: var(--background-color);
    color: var(--text-dark);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    /* Paper texture effect */
    background-image: 
        radial-gradient(circle at 1px 1px, rgba(255,255,255,0.15) 1px, transparent 0);
    background-size: 20px 20px;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
.header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--white);
    padding: 20px 0;
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header__title {
    font-size: 2rem;
    margin-bottom: 15px;
    text-align: center;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.header__logo {
    width: 40px;
    height: 40px;
    object-fit: contain;
}

.header__nav {
    display: flex;
    justify-content: center;
    gap: 10px;
    flex-wrap: wrap;
}

.nav__btn {
    background: rgba(255, 255, 255, 0.2);
    border: none;
    color: var(--white);
    padding: 10px 20px;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition);
    font-size: 1rem;
    font-weight: 500;
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

.nav__btn:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: translateY(-2px);
}

.nav__btn--active {
    background: var(--white);
    color: var(--primary-color);
}

/* Main content */
.main {
    flex: 1;
    padding: 40px 0;
}

/* Cards */
.card {
    background: var(--white);
    border-radius: var(--border-radius);
    padding: 30px;
    margin-bottom: 30px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    /* Paper texture for cards */
    background-image: 
        radial-gradient(circle at 1px 1px, rgba(120, 104, 230, 0.03) 1px, transparent 0);
    background-size: 15px 15px;
}

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

.card__title {
    font-size: 1.8rem;
    color: var(--primary-color);
    margin-bottom: 25px;
    text-align: center;
    position: relative;
}

.card__title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    border-radius: 2px;
}

/* Tab content */
.tab-content {
    display: none;
    animation: fadeIn 0.3s ease-in-out;
}

.tab-content--active {
    display: block;
}

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

/* Form styles */
.form {
    display: grid;
    gap: 25px;
}

.form__group {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.form__label {
    font-weight: 600;
    color: var(--text-dark);
    font-size: 1.1rem;
}

.form__input,
.form__select,
.form__textarea {
    padding: 12px 16px;
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 1rem;
    transition: var(--transition);
    background: var(--white);
}

.form__input:focus,
.form__select:focus,
.form__textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(120, 104, 230, 0.1);
}

.form__textarea {
    resize: vertical;
    min-height: 100px;
}

.form__input-group {
    display: flex;
    gap: 10px;
    align-items: center;
}

.form__input-group .form__input {
    flex: 1;
}

.form__help {
    color: var(--text-light);
    font-size: 0.9rem;
}

/* Intensity scale */
.intensity-scale {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.intensity-slider {
    -webkit-appearance: none;
    width: 100%;
    height: 8px;
    border-radius: 5px;
    background: linear-gradient(90deg, var(--light-blue), var(--accent-color));
    outline: none;
    cursor: pointer;
}

.intensity-slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.2);
    transition: var(--transition);
}

.intensity-slider::-webkit-slider-thumb:hover {
    transform: scale(1.1);
}

.intensity-slider::-moz-range-thumb {
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
    border: none;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.2);
}

.intensity-labels {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.9rem;
    color: var(--text-light);
}

#intensityValue {
    font-size: 1.2rem;
    font-weight: bold;
    color: var(--primary-color);
    background: var(--light-blue);
    padding: 5px 10px;
    border-radius: 20px;
}

/* Food grid */
.food-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    margin-bottom: 20px;
}

.food-category {
    background: var(--light-blue);
    padding: 15px;
    border-radius: var(--border-radius);
    border: 1px solid rgba(120, 104, 230, 0.1);
}

.food-category h4 {
    color: var(--primary-color);
    margin-bottom: 10px;
    font-size: 1rem;
}

.checkbox-label {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 8px;
    cursor: pointer;
    transition: var(--transition);
    padding: 5px;
    border-radius: 6px;
}

.checkbox-label:hover {
    background: rgba(120, 104, 230, 0.05);
}

.checkbox-label input[type="checkbox"] {
    display: none;
}

.checkbox-custom {
    width: 18px;
    height: 18px;
    border: 2px solid var(--border-color);
    border-radius: 4px;
    position: relative;
    transition: var(--transition);
    background: var(--white);
}

.checkbox-label input[type="checkbox"]:checked + .checkbox-custom {
    background: var(--primary-color);
    border-color: var(--primary-color);
}

.checkbox-label input[type="checkbox"]:checked + .checkbox-custom::after {
    content: '✓';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: var(--white);
    font-size: 12px;
    font-weight: bold;
}

/* Buttons */
.btn {
    padding: 12px 24px;
    border: none;
    border-radius: var(--border-radius);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
    display: inline-block;
    text-align: center;
    min-width: 120px;
}

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

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

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

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

.form__actions {
    display: flex;
    gap: 15px;
    justify-content: center;
    margin-top: 20px;
}

/* Stats grid */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.stat-card {
    background: linear-gradient(135deg, var(--light-blue), var(--white));
    padding: 20px;
    border-radius: var(--border-radius);
    text-align: center;
    border: 1px solid rgba(120, 104, 230, 0.1);
    transition: var(--transition);
}

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

.stat-card h3 {
    color: var(--primary-color);
    margin-bottom: 10px;
    font-size: 1rem;
}

.stat-number {
    font-size: 2rem;
    font-weight: bold;
    color: var(--primary-color);
    display: block;
}

.stat-text {
    font-size: 1.2rem;
    color: var(--text-dark);
    display: block;
}

/* Chart container */
.chart-container {
    background: var(--white);
    padding: 20px;
    border-radius: var(--border-radius);
    margin-bottom: 30px;
    box-shadow: var(--shadow);
    min-height: 300px;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* History list */
.history-list h3 {
    color: var(--primary-color);
    margin-bottom: 20px;
    font-size: 1.3rem;
}

.episode-list {
    display: grid;
    gap: 15px;
}

.episode-item {
    background: var(--light-blue);
    padding: 15px;
    border-radius: var(--border-radius);
    border-left: 4px solid var(--primary-color);
    transition: var(--transition);
}

.episode-item:hover {
    transform: translateX(5px);
    box-shadow: var(--shadow);
}

.episode-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 10px;
}

.episode-date {
    font-weight: 600;
    color: var(--primary-color);
}

.episode-intensity {
    background: var(--accent-color);
    color: var(--white);
    padding: 4px 8px;
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: bold;
}

.episode-details {
    display: grid;
    gap: 5px;
    font-size: 0.9rem;
    color: var(--text-light);
}

/* Tips grid */
.tips-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 25px;
}

.tip-card {
    background: linear-gradient(135deg, var(--light-blue), var(--white));
    padding: 25px;
    border-radius: var(--border-radius);
    border: 1px solid rgba(120, 104, 230, 0.1);
    transition: var(--transition);
}

.tip-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-hover);
}

.tip-card h3 {
    color: var(--primary-color);
    margin-bottom: 15px;
    font-size: 1.2rem;
    display: flex;
    align-items: center;
    gap: 8px;
}

.tip-card ul {
    list-style: none;
    padding: 0;
}

.tip-card li {
    padding: 8px 0;
    border-bottom: 1px solid rgba(120, 104, 230, 0.1);
    position: relative;
    padding-left: 20px;
}

.tip-card li:last-child {
    border-bottom: none;
}

.tip-card > ul > li::before {
    content: '•';
    color: var(--primary-color);
    position: absolute;
    left: 0;
    font-weight: bold;
}

/* Expander (details/summary) */
.expander {
    margin-top: 10px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    background: var(--white);
}

.expander > summary {
    cursor: pointer;
    padding: 10px 14px;
    font-weight: 600;
    color: var(--primary-color);
    list-style: none;
}

.expander[open] > summary {
    border-bottom: 1px solid var(--border-color);
}

.expander > summary::-webkit-details-marker {
    display: none;
}

.expander > summary::after {
    content: '+';
    float: right;
    transition: transform 0.2s ease;
}

.expander[open] > summary::after {
    transform: rotate(45deg);
}

.expander > *:not(summary) {
    padding: 12px 14px;
}

/* Checklist with badges */
.checklist {
    list-style: none;
    padding-left: 0;
    margin-top: 8px;
}

.checklist li {
    padding-left: 0;
    position: relative;
    display: flex;
    align-items: center;
    gap: 8px;
    border-bottom: 1px solid rgba(120, 104, 230, 0.08);
}

.checklist li::before {
    content: '';
    display: none;
}

.badge {
    display: inline-block;
    background: var(--light-blue);
    color: var(--primary-color);
    border: 1px solid rgba(120, 104, 230, 0.2);
    padding: 2px 8px;
    border-radius: 999px;
    font-size: 0.75rem;
    margin-right: 8px;
    line-height: 1;
    white-space: nowrap;
}

/* Callouts */
.callout {
    padding: 12px 14px;
    border-radius: 8px;
    border-left: 4px solid var(--primary-color);
    background: var(--light-blue);
    margin-top: 10px;
}

.callout.info {
    border-left-color: #2196F3;
    background: rgba(33, 150, 243, 0.08);
}

/* FAQ */
.faq-container {
    display: grid;
    gap: 15px;
}

.faq-item {
    background: var(--light-blue);
    border-radius: var(--border-radius);
    overflow: hidden;
    transition: var(--transition);
}

.faq-question {
    background: none;
    border: none;
    width: 100%;
    padding: 20px;
    text-align: left;
    cursor: pointer;
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--primary-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: var(--transition);
}

.faq-question:hover {
    background: rgba(120, 104, 230, 0.05);
}

.faq-question::after {
    content: '+';
    font-size: 1.5rem;
    transition: var(--transition);
}

.faq-question.active::after {
    transform: rotate(45deg);
}

.faq-answer {
    padding: 0 20px;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.faq-answer.active {
    padding: 0 20px 20px 20px;
    max-height: 200px;
}

.faq-answer p {
    color: var(--text-dark);
    line-height: 1.6;
}

/* Footer */
.footer {
    background: var(--primary-color);
    color: var(--white);
    padding: 20px 0;
    text-align: center;
    margin-top: auto;
}

.footer__text {
    font-size: 0.9rem;
    opacity: 0.9;
}

.footer__logo {
    width: 20px;
    height: 20px;
    object-fit: contain;
    vertical-align: middle;
    margin-right: 8px;
}

/* Loading */
.loading {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    color: var(--white);
}

.loading__spinner {
    width: 50px;
    height: 50px;
    border: 4px solid rgba(255, 255, 255, 0.3);
    border-top: 4px solid var(--white);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 20px;
}

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

/* Toast notifications */
.toast {
    position: fixed;
    top: 20px;
    right: 20px;
    background: var(--primary-color);
    color: var(--white);
    padding: 15px 20px;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-hover);
    z-index: 1001;
    display: flex;
    align-items: center;
    gap: 10px;
    animation: slideIn 0.3s ease;
}

.toast.success {
    background: #4CAF50;
}

.toast.error {
    background: var(--accent-color);
}

.toast__close {
    background: none;
    border: none;
    color: var(--white);
    font-size: 1.5rem;
    cursor: pointer;
    padding: 0;
    margin-left: 10px;
}

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

/* Responsive design */
@media (max-width: 1024px) {
    .container {
        padding: 0 20px;
    }
    
    .food-grid {
        grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    }
    
    .tips-grid {
        grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    }
}

@media (max-width: 768px) {
    .container {
        padding: 0 15px;
    }
    
    .header__title {
        font-size: 1.5rem;
    }
    
    .header__nav {
        gap: 5px;
        flex-wrap: wrap;
        justify-content: center;
    }
    
    .nav__btn {
        padding: 8px 15px;
        font-size: 0.9rem;
        flex: 1;
        min-width: 80px;
    }
    
    .main {
        padding: 20px 0;
    }
    
    .card {
        padding: 20px;
        margin-bottom: 20px;
    }
    
    .card__title {
        font-size: 1.5rem;
    }
    
    .food-grid {
        grid-template-columns: 1fr;
        gap: 15px;
    }
    
    .food-category {
        padding: 12px;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
        gap: 15px;
    }
    
    .tips-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .form__actions {
        flex-direction: column;
        align-items: stretch;
        gap: 10px;
    }
    
    .btn {
        width: 100%;
        padding: 14px 20px;
    }
    
    .form__input-group {
        flex-direction: column;
        gap: 10px;
    }
    
    .form__input-group .form__input {
        width: 100%;
    }
    
    .episode-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 5px;
    }
    
    .episode-item {
        padding: 12px;
    }
    
    .chart-container {
        padding: 15px;
        min-height: 250px;
    }
    
    .toast {
        right: 15px;
        left: 15px;
        top: 15px;
        padding: 12px 16px;
    }
    
    .intensity-labels {
        font-size: 0.8rem;
        flex-wrap: wrap;
        gap: 5px;
    }
    
    .intensity-labels span {
        flex: 1;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 10px;
    }
    
    .header {
        padding: 15px 0;
    }
    
    .header__title {
        font-size: 1.3rem;
        flex-direction: column;
        gap: 5px;
        margin-bottom: 10px;
    }
    
    .header__logo {
        width: 32px;
        height: 32px;
    }
    
    .header__nav {
        gap: 3px;
    }
    
    .nav__btn {
        padding: 6px 10px;
        font-size: 0.8rem;
        min-width: 70px;
    }
    
    .main {
        padding: 15px 0;
    }
    
    .card {
        padding: 15px;
        margin-bottom: 15px;
    }
    
    .card__title {
        font-size: 1.3rem;
        margin-bottom: 20px;
    }
    
    .form__label {
        font-size: 1rem;
    }
    
    .form__input,
    .form__select,
    .form__textarea {
        padding: 10px 12px;
        font-size: 0.9rem;
    }
    
    .intensity-labels {
        font-size: 0.75rem;
        flex-direction: column;
        gap: 3px;
    }
    
    #intensityValue {
        font-size: 1rem;
        padding: 3px 8px;
    }
    
    .food-category h4 {
        font-size: 0.9rem;
    }
    
    .checkbox-label {
        font-size: 0.9rem;
    }
    
    .stat-card {
        padding: 15px;
    }
    
    .stat-card h3 {
        font-size: 0.9rem;
    }
    
    .stat-number {
        font-size: 1.5rem;
    }
    
    .tip-card {
        padding: 15px;
    }
    
    .tip-card h3 {
        font-size: 1rem;
    }
    
    .tip-card li {
        font-size: 0.9rem;
        padding: 6px 0;
    }
    
    .faq-question {
        padding: 15px;
        font-size: 1rem;
    }
    
    .faq-answer {
        padding: 0 15px;
    }
    
    .faq-answer.active {
        padding: 0 15px 15px 15px;
    }
    
    .episode-item {
        padding: 10px;
    }
    
    .episode-details {
        font-size: 0.8rem;
    }
    
    .chart-container {
        padding: 10px;
        min-height: 200px;
    }
    
    .toast {
        right: 10px;
        left: 10px;
        top: 10px;
        padding: 10px 12px;
        font-size: 0.9rem;
    }
}

/* Print styles */
@media print {
    .header__nav,
    .form__actions,
    .btn {
        display: none;
    }
    
    .card {
        box-shadow: none;
        border: 1px solid #ccc;
    }
    
    .tab-content {
        display: block !important;
    }
}

/* High contrast mode */
@media (prefers-contrast: high) {
    :root {
        --primary-color: #000080;
        --secondary-color: #4B0082;
        --text-dark: #000000;
        --text-light: #333333;
        --border-color: #000000;
    }
}

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

/* Validation styles */
.field--valid {
    border-color: #4CAF50 !important;
    box-shadow: 0 0 0 2px rgba(76, 175, 80, 0.1) !important;
}

.field--invalid {
    border-color: #FFB4B4 !important;
    box-shadow: 0 0 0 2px rgba(255, 180, 180, 0.2) !important;
}

.field-feedback {
    margin-top: 5px;
    font-size: 0.9rem;
}

.field-feedback--error {
    color: #d32f2f;
}

.error-message {
    display: block;
    margin-bottom: 2px;
}

.error-message:last-child {
    margin-bottom: 0;
}

/* Empty state */
.empty-state {
    text-align: center;
    padding: 40px 20px;
    color: var(--text-light);
}

.empty-state p {
    margin-bottom: 10px;
}

.empty-state p:last-child {
    margin-bottom: 0;
}

/* Screen reader only content */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}