/*
   PCA Spotrates - Yield Curve Stress Testing
   Stylesheet based on Tebbe Consulting GmbH design
*/

/* ======= FONTS ======= */
@import url('https://fonts.googleapis.com/css2?family=Montserrat:wght@400;500;600;700&family=Source+Sans+3:wght@300;400;500;600;700&display=swap');

/* ======= BASE STYLES ======= */
:root {
    --primary-color: #1f5a7a;
    --primary-dark: #184660;
    --primary-light: #2b6a8b;
    --secondary-color: #6b8796;
    --accent-color: #c3d2db;
    --text-color: #2b2f33;
    --text-light: #6f7b83;
    --text-dark: #1b1f23;
    --text-white: #ffffff;
    --bg-light: #f5f7f9;
    --bg-graph: #eef2f6;
    --bg-gray: #e6ebef;
    --bg-panel: #ffffff;
    --border-color: #d9e1e7;
    --shadow-sm: 0 2px 6px rgba(20, 40, 60, 0.08);
    --shadow-md: 0 10px 24px rgba(20, 40, 60, 0.14);
    --shadow-lg: 0 24px 48px rgba(20, 40, 60, 0.18);
    --transition: all 0.2s ease;
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 3rem;
    --spacing-xl: 5rem;
    --container-width: 1400px;
    --border-radius: 0.3rem;
    --font-primary: 'Montserrat', sans-serif;
    --font-secondary: 'Source Sans 3', sans-serif;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-secondary);
    color: var(--text-color);
    line-height: 1.6;
    font-size: 16px;
    background-color: var(--bg-light);
}

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-primary);
    margin-bottom: var(--spacing-sm);
    color: var(--text-dark);
    font-weight: 600;
    line-height: 1.3;
}

p {
    margin-bottom: var(--spacing-sm);
}

a {
    color: var(--primary-color);
    text-decoration: none;
    transition: var(--transition);
}

a:hover {
    color: var(--primary-dark);
}

.container {
    width: 100%;
    max-width: var(--container-width);
    margin: 0 auto;
    background: var(--bg-panel);
    border-radius: 10px;
    box-shadow: var(--shadow-md);
    overflow: hidden;
    border: 1px solid var(--border-color);
}

/* ======= BUTTONS ======= */
.btn, button {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border-radius: var(--border-radius);
    font-weight: 500;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    font-family: var(--font-primary);
    border: none;
    font-size: 1rem;
    text-transform: none;
    letter-spacing: 0.3px;
}

.btn-primary, button:not(.export-btn):not(.cookie-close):not(.advanced-btn) {
    background-color: var(--primary-color);
    color: white;
    font-weight: 600;
    box-shadow: 0 4px 12px rgba(20, 24, 27, 0.18);
}

.btn-primary:hover, button:not(.export-btn):not(.cookie-close):not(.advanced-btn):hover:not(:disabled) {
    background-color: var(--primary-dark);
    color: white;
    box-shadow: 0 8px 18px rgba(20, 24, 27, 0.24);
    transform: translateY(-1px);
}

button:disabled {
    background-color: #6c757d;
    cursor: not-allowed;
    transform: none;
    opacity: 0.7;
}

.btn-secondary {
    background-color: white;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
    font-weight: 600;
    letter-spacing: 0.8px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.btn-secondary:hover {
    background-color: var(--primary-color);
    color: white;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

/* ======= HEADER ======= */
header {
    background-color: var(--bg-panel);
    color: var(--text-dark);
    padding: 0;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.site-header {
    display: grid;
}

.topbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 18px var(--spacing-md);
    background: var(--bg-panel);
}

.brand {
    display: flex;
    flex-direction: column;
    gap: 0.1rem;
}

.brand-title {
    font-family: var(--font-primary);
    font-size: 1.9rem;
    font-weight: 700;
    color: var(--primary-color);
    letter-spacing: 0.2px;
}

.brand-subtitle {
    font-family: var(--font-secondary);
    font-size: 0.85rem;
    color: var(--text-light);
}

.main-nav {
    display: flex;
    gap: 1.5rem;
    font-size: 0.95rem;
}

.main-nav a {
    color: var(--text-dark);
    font-weight: 600;
    position: relative;
}

.main-nav a::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: -6px;
    width: 100%;
    height: 2px;
    background: var(--primary-color);
    opacity: 0;
    transition: var(--transition);
}

.main-nav a:hover::after {
    opacity: 1;
}

.hero {
    background: linear-gradient(135deg, #1b506f, #295f7b);
    color: white;
    padding: calc(var(--spacing-lg) * 1.3) var(--spacing-md);
    text-align: center;
}

.app-title {
    font-family: var(--font-primary);
    font-size: 2.2rem;
    font-weight: 600;
    color: white;
    margin-bottom: 0.75rem;
}

header .subtitle {
    font-size: 1.1rem;
    color: rgba(255, 255, 255, 0.85);
    margin-bottom: 1.5rem;
}


/* ======= DOCUMENTATION SECTION ======= */
.documentation-section {
    padding: var(--spacing-md);
    background: var(--bg-light);
    border-bottom: 1px solid var(--border-color);
}

.documentation-toggle-container {
    text-align: center;
    margin-bottom: var(--spacing-sm);
}

.documentation-btn {
    background-color: transparent !important;
    color: var(--primary-color) !important;
    border: 1px solid var(--border-color) !important;
    padding: 12px 28px !important;
    text-transform: none;
    font-weight: 600;
    letter-spacing: 0.2px;
    box-shadow: none !important;
    transition: var(--transition);
    font-size: 1.05rem;
}

.documentation-btn:hover {
    background-color: var(--primary-color) !important;
    color: white !important;
    transform: translateY(0) !important;
    box-shadow: 0 2px 8px rgba(20, 24, 27, 0.18) !important;
}

#documentationContent {
    margin-top: var(--spacing-md);
    padding: var(--spacing-md);
    background: var(--bg-panel);
    border-radius: var(--border-radius);
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
    position: relative;
}

#documentationContent::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    border-radius: var(--border-radius) var(--border-radius) 0 0;
}

.doc-content {
    padding-top: 0.5rem;
}

.doc-content h3 {
    margin-top: var(--spacing-md);
    margin-bottom: var(--spacing-sm);
    color: var(--primary-color);
    font-size: 1.35rem;
}

.doc-content h3:first-child {
    margin-top: 0;
}

.doc-content h4 {
    margin-top: var(--spacing-sm);
    margin-bottom: var(--spacing-xs);
    color: var(--text-dark);
    font-size: 1.1rem;
}

.doc-content p {
    line-height: 1.8;
    color: var(--text-color);
    margin-bottom: var(--spacing-sm);
}

.doc-content blockquote {
    margin: var(--spacing-sm) 0;
    padding: var(--spacing-sm) var(--spacing-md);
    border-left: 4px solid var(--primary-color);
    background: var(--bg-graph);
    color: var(--text-dark);
    border-radius: var(--border-radius);
    line-height: 1.7;
}

.doc-figure {
    margin: var(--spacing-md) 0;
    padding: var(--spacing-sm);
    background: var(--bg-panel);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
    text-align: center;
}

.doc-figure img {
    max-width: 100%;
    height: auto;
    display: block;
    margin: 0 auto;
}

.doc-figure .caption {
    margin-top: 0.75rem;
    color: var(--text-light);
    font-size: 0.9rem;
}

.doc-content ul {
    margin: var(--spacing-sm) 0;
    padding-left: 2rem;
}

.doc-content li {
    margin-bottom: 0.5rem;
    line-height: 1.6;
    color: var(--text-color);
}

.discussion-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-md);
    margin-top: var(--spacing-sm);
}

.pro-section, .contra-section {
    padding: var(--spacing-sm);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
    background: var(--bg-panel);
    border: 1px solid var(--border-color);
}

.pro-section {
    border-left: 3px solid var(--primary-color);
}

.contra-section {
    border-left: 3px solid var(--secondary-color);
}

.pro-section ul, .contra-section ul {
    margin-top: var(--spacing-xs);
}

.pro-section li {
    color: #155724;
}

.contra-section li {
    color: #856404;
}

/* ======= CONTROLS SECTION ======= */
.controls {
    padding: var(--spacing-md);
    background: var(--bg-light);
    border-bottom: 1px solid var(--border-color);
}

.form-group {
    display: flex;
    gap: var(--spacing-sm);
    align-items: flex-end;
    flex-wrap: wrap;
}

.input-group {
    flex: 1;
    min-width: 200px;
}

label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--text-color);
    font-family: var(--font-primary);
}

input[type="date"],
input[type="number"] {
    width: 100%;
    padding: 12px;
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 16px;
    font-family: var(--font-secondary);
    transition: var(--transition);
}

input[type="date"]:focus,
input[type="number"]:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(20, 83, 122, 0.1);
}

.advanced-toggle-container {
    text-align: center;
    margin-top: var(--spacing-sm);
}

.advanced-btn {
    background-color: transparent !important;
    color: var(--primary-color) !important;
    border: 1px solid var(--border-color) !important;
    padding: 10px 24px !important;
    text-transform: none;
    font-weight: 600;
    letter-spacing: 0.2px;
    box-shadow: none !important;
    transition: var(--transition);
}

.advanced-btn:hover {
    background-color: var(--primary-color) !important;
    color: white !important;
    transform: translateY(0) !important;
    box-shadow: 0 2px 8px rgba(20, 24, 27, 0.18) !important;
}

#advancedOptions {
    margin-top: var(--spacing-md);
    padding: var(--spacing-md);
    background: var(--bg-panel);
    border-radius: var(--border-radius);
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
    position: relative;
}

#advancedOptions::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    border-radius: var(--border-radius) var(--border-radius) 0 0;
}

#advancedOptions h3 {
    margin-bottom: var(--spacing-sm);
    margin-top: 0.5rem;
    color: var(--primary-color);
    font-size: 1.2rem;
}

small {
    color: var(--text-light);
    font-size: 0.85em;
    display: block;
    margin-top: 0.25rem;
}

/* ======= VALIDATION ======= */
.validation-error {
    color: #dc3545;
    font-size: 0.85em;
    margin-top: 5px;
    display: none;
}

/* ======= ALERTS ======= */
.error, .warning {
    padding: var(--spacing-sm);
    margin: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--border-radius);
    display: none;
}

.error {
    background: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

.error strong {
    display: block;
    margin-bottom: 5px;
    font-size: 1.1em;
}

.error-details {
    margin-top: 10px;
    padding-top: 10px;
    border-top: 1px solid #f5c6cb;
    font-size: 0.9em;
}

.warning {
    background: #fff3cd;
    color: #856404;
    border: 1px solid #ffeaa7;
}

/* ======= LOADING ======= */
.loading {
    display: none;
    text-align: center;
    padding: calc(var(--spacing-lg) * 1.5);
}

.spinner {
    border: 4px solid var(--bg-light);
    border-top: 4px solid var(--primary-color);
    border-radius: 50%;
    width: 50px;
    height: 50px;
    animation: spin 1s linear infinite;
    margin: 0 auto var(--spacing-sm);
}

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

.loading p {
    color: var(--text-light);
    margin-bottom: 0.5rem;
}

/* ======= DEMO BADGE ======= */
.demo-badge {
    display: inline-block;
    background: rgba(255, 255, 255, 0.2);
    color: white;
    padding: 4px 10px;
    border-radius: 999px;
    font-size: 0.75rem;
    margin-left: 8px;
    letter-spacing: 1px;
    text-transform: uppercase;
}

/* ======= EXPORT SECTION ======= */
.export-section {
    display: flex;
    gap: var(--spacing-sm);
    margin: var(--spacing-md) 0;
    justify-content: center;
    flex-wrap: wrap;
}

.export-btn {
    padding: 12px 25px !important;
    background: var(--primary-color) !important;
    color: white !important;
    border: none;
    border-radius: var(--border-radius);
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 8px;
    text-transform: none;
}

.export-btn:hover:not(:disabled) {
    transform: translateY(-1px);
    box-shadow: 0 6px 14px rgba(20, 24, 27, 0.2);
}

.export-btn:disabled {
    background: #6c757d !important;
    cursor: not-allowed;
    transform: none;
}

/* ======= RESULTS SECTION ======= */
.results {
    display: none;
    padding: var(--spacing-md);
}

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

.section-title {
    font-size: 1.5rem;
    color: var(--text-dark);
    margin-bottom: var(--spacing-sm);
    padding-bottom: var(--spacing-xs);
    border-bottom: 2px solid var(--primary-color);
    position: relative;
}

.description {
    color: var(--text-light);
    margin-bottom: var(--spacing-sm);
    line-height: 1.6;
}

/* ======= STATISTICS ======= */
.stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
}

.stat-card {
    background: var(--bg-panel);
    color: var(--text-dark);
    padding: var(--spacing-sm);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
    text-align: center;
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

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

.stat-label {
    font-size: 0.9em;
    opacity: 0.9;
    margin-bottom: 0.5rem;
    font-family: var(--font-primary);
    color: var(--text-light);
}

.stat-value {
    font-size: 1.8em;
    font-weight: 700;
    font-family: var(--font-primary);
    color: var(--text-dark);
}

/* ======= PLOTS ======= */
.plot-container {
    margin-top: var(--spacing-sm);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    overflow: hidden;
    background: var(--bg-panel);
    box-shadow: var(--shadow-sm);
    width: 100%;
}

#yieldCurvePlot {
    width: 100% !important;
    height: 900px !important;
}

#yieldCurvePlot .plotly {
    width: 100% !important;
    height: 100% !important;
}

/* ======= FOOTER ======= */
.footer {
    text-align: center;
    padding: var(--spacing-sm);
    background: var(--bg-light);
    color: var(--text-light);
    font-size: 0.9em;
    border-top: 1px solid var(--border-color);
}

.footer a {
    color: var(--primary-color);
    text-decoration: none;
    transition: var(--transition);
}

.footer a:hover {
    color: var(--primary-dark);
    text-decoration: underline;
}

/* ======= RESPONSIVE STYLES ======= */
@media (max-width: 992px) {
    .app-title {
        font-size: 2rem;
    }

    .section-title {
        font-size: 1.3rem;
    }

    .container {
        border-radius: 10px;
    }
}

@media (max-width: 768px) {
    .topbar {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.75rem;
    }

    .main-nav {
        flex-wrap: wrap;
        gap: 1rem;
    }

    .hero {
        padding: calc(var(--spacing-lg) * 1.1) var(--spacing-sm);
    }

    .form-group {
        flex-direction: column;
    }

    .input-group {
        width: 100%;
    }

    .stats {
        grid-template-columns: 1fr;
    }

    .app-title {
        font-size: 1.7rem;
    }

    header .subtitle {
        font-size: 1rem;
    }
}

@media (max-width: 576px) {
    body {
        padding: 10px;
    }

    .container {
        border-radius: 8px;
    }

    .section-title {
        font-size: 1.2rem;
    }

    .export-section {
        flex-direction: column;
    }
}