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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
}

.container {
    max-width: 900px;
    margin: 0 auto;
    background: white;
    border-radius: 12px;
    padding: 30px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
}

h1 {
    color: #333;
    margin-bottom: 10px;
    text-align: center;
}

.description {
    text-align: center;
    color: #666;
    margin-bottom: 30px;
}

.observed-box {
    background: #f8f9fa;
    border: 3px solid #667eea;
    border-radius: 8px;
    padding: 20px;
    margin-bottom: 25px;
}

.observed-box h2 {
    color: #667eea;
    margin-bottom: 15px;
    font-size: 1.3em;
}

#text-content {
    background: white;
    padding: 15px;
    border-radius: 6px;
    margin-bottom: 15px;
    border-left: 4px solid #667eea;
}

#element-container {
    min-height: 60px;
    background: white;
    border-radius: 6px;
    padding: 10px;
    border: 2px dashed #ddd;
}

.dynamic-element {
    background: #e7f3ff;
    border: 2px solid #2196F3;
    border-radius: 6px;
    padding: 10px;
    margin: 5px 0;
    animation: slideIn 0.3s ease;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateX(-20px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.controls {
    margin-bottom: 25px;
}

.controls h3 {
    color: #333;
    margin-bottom: 15px;
}

.button-group {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

button {
    background: #667eea;
    color: white;
    border: none;
    padding: 12px 20px;
    border-radius: 6px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 600;
    transition: all 0.3s ease;
}

button:hover {
    background: #5568d3;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}

button:active {
    transform: translateY(0);
}

.log-section {
    background: #f8f9fa;
    border-radius: 8px;
    padding: 20px;
}

.log-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
}

.log-header h3 {
    color: #333;
}

#btn-clear-log {
    background: #dc3545;
    padding: 8px 16px;
    font-size: 13px;
}

#btn-clear-log:hover {
    background: #c82333;
}

.log-container {
    background: #2d2d2d;
    color: #f8f9fa;
    border-radius: 6px;
    padding: 15px;
    max-height: 400px;
    overflow-y: auto;
    font-family: 'Courier New', monospace;
    font-size: 13px;
    line-height: 1.6;
}

.log-entry {
    margin-bottom: 12px;
    padding: 10px;
    background: #3a3a3a;
    border-radius: 4px;
    border-left: 4px solid #667eea;
}

.log-entry .log-type {
    color: #4caf50;
    font-weight: bold;
}

.log-entry .log-time {
    color: #999;
    font-size: 11px;
}

.log-entry .log-details {
    color: #ffd700;
    margin-top: 5px;
}

.log-container::-webkit-scrollbar {
    width: 8px;
}

.log-container::-webkit-scrollbar-track {
    background: #1a1a1a;
    border-radius: 4px;
}

.log-container::-webkit-scrollbar-thumb {
    background: #667eea;
    border-radius: 4px;
}

.log-container::-webkit-scrollbar-thumb:hover {
    background: #5568d3;
}