body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #f4f7f6;
    color: #333;
    margin: 0;
    padding: 2rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    min-height: 100vh;
}

.container {
    background-color: #ffffff;
    width: 100%;
    max-width: 800px;
    padding: 2.5rem;
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
    margin-bottom: auto;
    box-sizing: border-box;
}

.header-wrapper {
    border-bottom: 2px solid #f0f0f0;
    margin-bottom: 2rem;
    padding-bottom: 1rem;
}

.header-wrapper h1 {
    color: #c92a2a;
    margin-bottom: 0.5rem;
    font-size: 2.2rem;
}

.header-wrapper p {
    color: #666;
    margin-top: 0;
    font-size: 1.1rem;
}

h2 {
    color: #2d3748;
    margin-top: 2.5rem;
    border-left: 4px solid #c92a2a;
    padding-left: 0.8rem;
}

.detail-content {
    margin-bottom: 2.5rem;
    line-height: 1.6;
}

.back-link {
    display: inline-block;
    text-decoration: none;
    color: #c92a2a;
    font-weight: bold;
    margin-bottom: 1.5rem;
    transition: color 0.3s ease;
}

.back-link:hover {
    color: #a02020;
}

.red-link,
.red-link:visited {
    color: #df2222;
    text-decoration: none;
}

.red-link:hover {
    text-decoration: underline;
}

.solution-table {
    width: 100%;
    border-collapse: collapse;
    margin: 1.5rem 0;
    background-color: #fff;
    box-shadow: 0 2px 8px rgba(0,0,0,0.05);
    border-radius: 8px;
    overflow: hidden;
}

.solution-table th, 
.solution-table td {
    padding: 12px 15px;
    text-align: left;
    border-bottom: 1px solid #e2e8f0;
}

.solution-table th {
    background-color: #c92a2a;
    color: white;
    font-weight: bold;
}

.solution-table tr:nth-child(even) {
    background-color: #f8fafc;
}

.solution-table tr:hover {
    background-color: #f1f5f9;
}

.question-box {
    background-color: #f8fafc;
    border-left: 4px solid #c92a2a;
    padding: 1rem;
    margin-bottom: 1.5rem;
    border-radius: 0 8px 8px 0;
}

.question {
    font-weight: bold;
    margin-top: 0;
    color: #2d3748;
}

.answer {
    margin-bottom: 0;
    color: #4a5568;
}

.solution {
    background-color: #fff5f5;
    border: 1px solid #fed7d7;
    border-left: 4px solid #c92a2a;
    padding: 1rem 1.5rem;
    margin: 1.5rem 0;
    border-radius: 4px;
    color: #2d3748;
}

.content-image {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
    box-shadow: 0 4px 10px rgba(0,0,0,0.1);
    margin: 1.5rem 0;
    display: block;
}

.site-footer {
    background-color: transparent; 
    border-top: 2px solid #cbd5e0; 
    text-align: center;
    padding: 2rem 1rem;
    margin-top: 4rem; 
    width: 100%;
    max-width: 800px;
}

.site-footer p {
    color: #718096; 
    font-size: 0.95rem;
    margin: 0;
}