:root {
    --primary-color: #2c3e50;
    --secondary-color: #3498db;
    --accent-color: #e67e22;
    --bg-light: #f4f6f7;
    --text-color: #333;
    --white: #ffffff;
    --card-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

body {
    font-family: 'Roboto', sans-serif;
    margin: 0;
    padding: 0;
    line-height: 1.6;
    background-color: var(--bg-light);
    color: var(--text-color);
}

.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 0 20px;
}

header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--white);
    padding: 60px 0;
    text-align: center;
    box-shadow: 0 2px 10px rgba(0,0,0,0.2);
}

header h1 {
    margin: 0 0 10px 0;
    font-size: 2.5em;
    font-weight: 700;
}

header .subtitle {
    font-size: 1.2em;
    opacity: 0.9;
    font-weight: 300;
}

main {
    padding: 40px 0;
}

section {
    margin-bottom: 40px;
}

h2 {
    color: var(--primary-color);
    border-left: 5px solid var(--accent-color);
    padding-left: 15px;
    margin-bottom: 20px;
}

h3 {
    color: var(--secondary-color);
    margin-top: 0;
}

.card {
    background: var(--white);
    padding: 25px;
    border-radius: 8px;
    box-shadow: var(--card-shadow);
}

ul {
    padding-left: 20px;
}

li {
    margin-bottom: 10px;
}

.groups-container {
    display: flex;
    gap: 20px;
    margin-top: 20px;
    flex-wrap: wrap;
}

.group-box {
    flex: 1;
    background: #f8f9fa;
    padding: 15px;
    border-left: 4px solid var(--secondary-color);
    border-radius: 4px;
    min-width: 250px;
}

.group-box h4 {
    margin-top: 0;
    color: var(--primary-color);
}

.design-list li, .timeline-steps li {
    margin-bottom: 8px;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 15px;
}

th, td {
    padding: 12px 15px;
    text-align: left;
    border-bottom: 1px solid #ddd;
}

th {
    background-color: var(--primary-color);
    color: var(--white);
}

tr:hover {
    background-color: #f1f1f1;
}

.section-header td {
    background-color: #e9ecef;
    font-weight: bold;
    color: var(--primary-color);
}

.total-row td {
    background-color: #dfe6e9;
    font-weight: bold;
    font-size: 1.1em;
}

.note {
    font-size: 0.9em;
    color: #7f8c8d;
    margin-top: 10px;
    font-style: italic;
}

footer {
    text-align: center;
    padding: 20px;
    background-color: var(--primary-color);
    color: var(--white);
    margin-top: 40px;
}

@media (max-width: 600px) {
    header h1 {
        font-size: 1.8em;
    }
    
    .groups-container {
        flex-direction: column;
    }
    
    table {
        font-size: 0.9em;
        display: block;
        overflow-x: auto;
    }
}