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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', 'Helvetica Neue', sans-serif;
    line-height: 1.8;
    color: #2c3e50;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    padding: 20px;
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    background-color: white;
    padding: 60px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.3);
    border-radius: 12px;
    animation: fadeIn 0.6s ease-in;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

header {
    text-align: center;
    margin-bottom: 50px;
    border-bottom: 3px solid #2c3e50;
    padding-bottom: 30px;
}

h1 {
    font-size: 2.2em;
    color: #2c3e50;
    margin-bottom: 20px;
    font-weight: 700;
    line-height: 1.3;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.1);
}

.authors {
    font-size: 1.1em;
    color: #555;
    margin: 15px 0;
    font-style: italic;
}

.date {
    color: #777;
    font-size: 0.95em;
}

.abstract {
    background: linear-gradient(135deg, #667eea15 0%, #764ba215 100%);
    padding: 30px;
    margin: 40px 0;
    border-left: 5px solid #667eea;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
}

.abstract h2 {
    color: #2c3e50;
    margin-bottom: 15px;
    font-size: 1.3em;
}

h2 {
    color: #2c3e50;
    font-size: 1.8em;
    margin-top: 50px;
    margin-bottom: 20px;
    border-bottom: 2px solid #ecf0f1;
    padding-bottom: 10px;
}

h3 {
    color: #34495e;
    font-size: 1.4em;
    margin-top: 35px;
    margin-bottom: 15px;
}

h4 {
    color: #555;
    font-size: 1.2em;
    margin-top: 25px;
    margin-bottom: 12px;
    font-style: italic;
}

p {
    margin-bottom: 15px;
    text-align: justify;
    font-size: 1.05rem;
    color: #34495e;
}

/* Navigation styles */
nav {
    display: flex;
    align-items: center;
    gap: 15px;
    padding: 15px 0;
    flex-wrap: wrap;
}

nav a {
    color: #667eea;
    text-decoration: none;
    font-weight: 500;
    padding: 8px 16px;
    border-radius: 6px;
    transition: all 0.3s ease;
    background-color: #f8f9fa;
}

nav a:hover {
    background-color: #667eea;
    color: white;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(102, 126, 234, 0.3);
}

/* Link styles */
a {
    color: #667eea;
    text-decoration: none;
    transition: color 0.3s ease;
}

a:hover {
    color: #764ba2;
    text-decoration: underline;
}

/* List improvements */
ul, ol {
    margin: 20px 0;
    padding-left: 30px;
}

li {
    margin-bottom: 12px;
    line-height: 1.8;
}

.chart-container {
    margin: 40px 0;
    padding: 25px;
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    border: 1px solid #dee2e6;
    border-radius: 12px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.08);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.chart-container:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 20px rgba(0,0,0,0.12);
}

.chart-title {
    text-align: center;
    font-weight: bold;
    color: #2c3e50;
    margin-bottom: 15px;
    font-size: 1.1em;
}

.chart-caption {
    text-align: center;
    font-style: italic;
    color: #666;
    font-size: 0.9em;
    margin-top: 10px;
}

canvas {
    max-height: 400px;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin: 30px 0;
    font-size: 0.95em;
}

th, td {
    border: 1px solid #ddd;
    padding: 12px;
    text-align: left;
}

th {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-size: 0.85em;
}

tr:nth-child(even) {
    background-color: #f8f9fa;
}

tr {
    transition: background-color 0.3s ease;
}

tr:hover {
    background-color: #e9ecef;
}

.methodology-box {
    background: linear-gradient(135deg, #fff9e6 0%, #fffbf0 100%);
    border-left: 5px solid #f39c12;
    padding: 25px;
    margin: 30px 0;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(243, 156, 18, 0.1);
}

.key-finding {
    background: linear-gradient(135deg, #e8f8f5 0%, #d1f2eb 100%);
    border-left: 5px solid #16a085;
    padding: 25px;
    margin: 25px 0;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(22, 160, 133, 0.1);
}

.reference-section {
    margin-top: 50px;
    padding-top: 30px;
    border-top: 3px solid transparent;
    border-image: linear-gradient(90deg, #667eea 0%, #764ba2 100%);
    border-image-slice: 1;
}

.reference-section h2 {
    color: #2c3e50;
    margin-bottom: 25px;
    font-size: 2em;
    text-shadow: 1px 1px 2px rgba(0,0,0,0.1);
}

.reference-section ol {
    counter-reset: reference-counter;
    list-style: none;
    padding-left: 0;
}

.reference-section li {
    counter-increment: reference-counter;
    margin-bottom: 20px;
    padding-left: 50px;
    position: relative;
    line-height: 1.8;
    background-color: rgba(255,255,255,0.5);
    padding: 15px 15px 15px 50px;
    border-radius: 8px;
    transition: all 0.3s ease;
    border-left: 4px solid transparent;
}

.reference-section li:hover {
    background-color: rgba(255,255,255,0.8);
    transform: translateX(5px);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.15);
    border-left-color: #667eea;
}

.reference-section li::before {
    content: "[" counter(reference-counter) "]";
    position: absolute;
    left: 15px;
    font-weight: 700;
    color: #667eea;
    font-size: 1.1em;
}

.reference {
    margin-bottom: 12px;
    padding-left: 30px;
    text-indent: -30px;
    font-size: 0.9em;
}

.equation {
    text-align: center;
    margin: 25px 0;
    font-family: 'Courier New', monospace;
    font-size: 1.1em;
    padding: 20px;
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    border: 2px solid #667eea;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(102, 126, 234, 0.1);
    transition: all 0.3s ease;
}

.equation:hover {
    box-shadow: 0 6px 16px rgba(102, 126, 234, 0.2);
    transform: scale(1.02);
}

.highlight {
    background: linear-gradient(120deg, #fff3cd 0%, #ffeaa7 100%);
    padding: 3px 8px;
    font-weight: 600;
    border-radius: 4px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}

/* Smooth scrolling */
html {
    scroll-behavior: smooth;
}

/* Selection styling */
::selection {
    background-color: #667eea;
    color: white;
}

::-moz-selection {
    background-color: #667eea;
    color: white;
}

/* Code blocks */
code {
    background-color: #f8f9fa;
    padding: 2px 6px;
    border-radius: 4px;
    font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
    font-size: 0.9em;
    color: #e74c3c;
}

/* Blockquote */
blockquote {
    border-left: 4px solid #667eea;
    padding-left: 20px;
    margin: 20px 0;
    font-style: italic;
    color: #555;
    background-color: #f8f9fa;
    padding: 15px 20px;
    border-radius: 4px;
}

/* Strong emphasis */
strong {
    color: #2c3e50;
    font-weight: 600;
}

/* Improved readability for emphasis */
em {
    color: #555;
    font-style: italic;
}

/* Footer styling */
footer {
    margin-top: 60px;
    padding: 30px 0;
    border-top: 3px solid transparent;
    border-image: linear-gradient(90deg, #667eea 0%, #764ba2 100%);
    border-image-slice: 1;
    text-align: center;
    color: #555;
    font-size: 0.9em;
    background: linear-gradient(135deg, rgba(255,255,255,0.5) 0%, rgba(255,255,255,0.8) 100%);
    border-radius: 8px;
    padding: 30px;
}

footer p {
    margin: 8px 0;
    line-height: 1.6;
}

footer strong {
    color: #667eea;
}

@media print {
    body {
        background: white;
    }
    .container {
        box-shadow: none;
        padding: 20px;
        background: white;
    }
    .navigation {
        display: none;
    }
    .chart-container {
        page-break-inside: avoid;
    }
}

@media (max-width: 768px) {
    .container {
        padding: 20px;
        margin: 10px;
    }
    h1 {
        font-size: 1.6em;
    }
    h2 {
        font-size: 1.4em;
    }
    .navigation {
        flex-direction: column;
        gap: 10px;
    }
    .navigation a {
        width: 100%;
        text-align: center;
    }
    table {
        font-size: 0.85em;
    }
    th, td {
        padding: 8px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 15px;
        margin: 5px;
    }
    h1 {
        font-size: 1.4em;
    }
    h2 {
        font-size: 1.2em;
    }
    .chart-container {
        padding: 15px;
    }
}