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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    min-height: 100vh;
    padding: 20px;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    background: white;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    overflow: hidden;
    margin-top: 30px;
    margin-bottom: 30px;
}

.header {
    background: linear-gradient(135deg, #2c3e50 0%, #3498db 100%);
    color: white;
    padding: 30px;
    text-align: center;
}

.header h1 {
    margin: 0;
    font-size: 2.2rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
}

.header p {
    opacity: 0.9;
    margin: 10px 0 0 0;
    font-size: 1.1rem;
}

.content {
    padding: 30px;
}

.input-section {
    margin-bottom: 25px;
}

.input-method {
    margin-bottom: 20px;
}

.form-group {
    margin-bottom: 20px;
}

.btn-primary {
    background: linear-gradient(135deg, #3498db 0%, #2c3e50 100%);
    border: none;
    padding: 12px 30px;
    font-weight: 600;
    border-radius: 8px;
    transition: all 0.3s;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(52, 152, 219, 0.4);
}

.result-section {
    background: #f8f9fa;
    padding: 20px;
    border-radius: 10px;
    border-left: 5px solid #3498db;
    margin-top: 20px;
    display: none;
}

.citation-result {
    position: relative;
}

#citation-output {
    width: 100%;
    height: 150px;
    border: 1px solid #ddd;
    border-radius: 5px;
    padding: 15px;
    font-family: 'Courier New', monospace;
    background: white;
    resize: vertical;
}

.loading {
    text-align: center;
    padding: 20px;
    display: none;
}

.alert {
    margin-top: 15px;
    display: none;
    align-items: center;
    gap: 10px;
}

.footer {
    text-align: center;
    padding: 20px;
    background: #f8f9fa;
    color: #6c757d;
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.input-group {
    margin-bottom: 15px;
}

@media (max-width: 768px) {
    .header h1 {
        font-size: 1.8rem;
    }
    
    .content {
        padding: 20px;
    }
    
    .form-row {
        flex-direction: column;
        gap: 10px;
    }
    
    .input-method div {
        flex-direction: column;
        gap: 10px;
    }
}