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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: #f5f7fa;
    color: #333;
    line-height: 1.6;
    padding: 20px;
}

header, footer {
    text-align: center;
    margin-bottom: 30px;
}

h1 {
    color: #2c3e50;
    margin-bottom: 10px;
}

.module-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    max-width: 1200px;
    margin: 0 auto;
}

.module-card {
    background: white;
    border-radius: 8px;
    padding: 20px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    text-decoration: none;
    color: inherit;
    transition: transform 0.2s, box-shadow 0.2s;
}

.module-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 6px 12px rgba(0,0,0,0.15);
}

.module-card h2 {
    color: #2980b9;
    margin-bottom: 10px;
    font-size: 1.3rem;
}

/* Page layout */
.container {
    max-width: 1200px;
    margin: 0 auto;
    background: white;
    border-radius: 12px;
    padding: 25px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

.chart-row {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    margin-top: 20px;
}

.chart-container {
    flex: 2;
    min-width: 500px;
    position: relative;
}

canvas {
    width: 100%;
    height: auto;
    border: 1px solid #ddd;
    border-radius: 8px;
    background: white;
    cursor: crosshair;
}

.controls {
    flex: 1;
    min-width: 250px;
    background: #f8f9fa;
    padding: 20px;
    border-radius: 8px;
}

.control-group {
    margin-bottom: 20px;
    border-bottom: 1px solid #ddd;
    padding-bottom: 15px;
}

.control-group h3 {
    margin-bottom: 10px;
    color: #2c3e50;
    font-size: 1.1rem;
}

label {
    display: block;
    margin: 8px 0 4px;
    font-weight: 600;
    font-size: 0.9rem;
}

input[type="number"], input[type="range"] {
    width: 100%;
    padding: 8px;
    border: 1px solid #ccc;
    border-radius: 4px;
    margin-bottom: 10px;
}

button {
    background: #3498db;
    color: white;
    border: none;
    padding: 10px 15px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.9rem;
    margin-right: 8px;
    margin-bottom: 8px;
    transition: background 0.2s;
}

button:hover {
    background: #2980b9;
}

button.secondary {
    background: #95a5a6;
}

button.secondary:hover {
    background: #7f8c8d;
}

.marker-list {
    max-height: 200px;
    overflow-y: auto;
    background: white;
    padding: 10px;
    border-radius: 4px;
    border: 1px solid #ddd;
    font-size: 0.85rem;
}

.marker-item {
    padding: 4px 0;
    border-bottom: 1px dashed #eee;
    display: flex;
    justify-content: space-between;
}

.zoom-slider {
    width: 100%;
    margin: 10px 0;
}

.info-box {
    background: #e1f0fa;
    padding: 15px;
    border-radius: 6px;
    margin: 20px 0;
    font-size: 0.95rem;
    border-left: 4px solid #3498db;
}

footer {
    margin-top: 40px;
    color: #7f8c8d;
    font-size: 0.9rem;
}

/* --- Additional Styles for Enhancements --- */
.marker.draggable {
    cursor: grab;
}
.marker.draggable:active {
    cursor: grabbing;
}
.export-btn {
    background: #27ae60;
}
.export-btn:hover {
    background: #2ecc71;
}
.login-container {
    max-width: 400px;
    margin: 50px auto;
    padding: 20px;
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}
.form-group {
    margin-bottom: 15px;
}
.form-group label {
    display: block;
    margin-bottom: 5px;
}
.form-group input {
    width: 100%;
    padding: 8px;
    border: 1px solid #ddd;
    border-radius: 4px;
}
.step-box {
    background: #f0f7ff;
    border-left: 4px solid #3498db;
    padding: 15px;
    margin: 20px 0;
    border-radius: 4px;
}
.step-box h4 {
    margin-top: 0;
    color: #2c3e50;
}
.slider-group {
    margin: 20px 0;
    padding: 15px;
    background: #f9f9f9;
    border-radius: 6px;
}
.slider-group label {
    font-weight: 600;
    display: inline-block;
    width: 150px;
}
.slider-group output {
    font-weight: 600;
    color: #e67e22;
    margin-left: 10px;
}