body {
    background-color: #d2d2d2;
    min-height: 100vh;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

.registration-container {
    padding: 20px;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
}

.registration-card {
    background: white;
    border-radius: 20px;
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.1);
    padding: 30px;
    width: 100%;
    max-width: 600px;
}

.card-header {
    text-align: center;
    margin-bottom: 30px;
}

.card-title {
    color: #333;
    font-size: 28px;
    font-weight: 600;
    margin-bottom: 10px;
}

.card-subtitle {
    color: #666;
    font-size: 14px;
}

.form-label {
    font-weight: 500;
    color: #333;
    margin-bottom: 8px;
}

.required {
    color: #e74c3c;
}

.form-control, .form-select {
    border: 2px solid #e9ecef;
    border-radius: 8px;
    padding: 12px 15px;
    font-size: 14px;
    transition: all 0.3s ease;
}

.form-control:focus, .form-select:focus {
    border-color: #667eea;
    box-shadow: 0 0 0 0.2rem rgba(102, 126, 234, 0.25);
}

.error-message {
    color: #e74c3c;
    font-size: 12px;
    margin-top: 5px;
}


.agreement-content {
    border: 1px solid #e9ecef;
    border-radius: 8px;
    padding: 15px;
    background: #f8f9fa;
    margin-bottom: 15px;
    line-height: 1.5;
}

.signature-container {
    border: 2px dashed #ddd;
    border-radius: 8px;
    padding: 15px;
    text-align: center;
    background: #fafafa;
}

.signature-canvas {
    border: 1px solid #ddd;
    border-radius: 4px;
    background: white;
    cursor: crosshair;
    display: block;
    margin: 0 auto;
}

.signature-controls {
    margin-top: 10px;
}

.btn-primary {
    background: linear-gradient(45deg, #667eea, #764ba2);
    border: none;
    border-radius: 8px;
    padding: 12px 30px;
    font-weight: 500;
    font-size: 16px;
    transition: all 0.3s ease;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
}

.btn-outline-secondary {
    border-radius: 6px;
    padding: 8px 16px;
    font-size: 14px;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .registration-container {
        padding: 10px;
    }

    .registration-card {
        padding: 20px;
        border-radius: 15px;
    }

    .card-title {
        font-size: 24px;
    }

    .signature-canvas {
        width: 100%;
        max-width: 280px;
    }
}

@media (max-width: 480px) {
    .registration-card {
        padding: 15px;
    }

    .signature-canvas {
        max-width: 250px;
        height: 150px;
    }
}

/* 加载状态 */
.loading {
    position: relative;
    pointer-events: none;
}

.loading::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 20px;
    height: 20px;
    margin: -10px 0 0 -10px;
    border: 2px solid #fff;
    border-radius: 50%;
    border-top-color: transparent;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* 成功/错误提示 */
.alert {
    border-radius: 8px;
    margin-bottom: 20px;
}