/* ============================================
   Reset & Base Styles
   ============================================ */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Helvetica', 'Arial', sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
}

/* ============================================
   Container
   ============================================ */
.container {
    max-width: 1200px;
    margin: 0 auto;
    background: white;
    border-radius: 20px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    padding: 40px;
}

/* ============================================
   Typography
   ============================================ */
h1 {
    text-align: center;
    color: #333;
    margin-bottom: 10px;
    font-size: 32px;
}

.subtitle {
    text-align: center;
    color: #666;
    margin-bottom: 40px;
    font-size: 16px;
}

/* ============================================
   Drop Zone
   ============================================ */
#dropZone {
    border: 3px dashed #ccc;
    border-radius: 15px;
    padding: 60px 40px;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    background: #fafafa;
    position: relative;
}

#dropZone:hover {
    border-color: #FC4C02;
    background: #fff5f2;
    transform: translateY(-2px);
}

#dropZone.drag-over {
    border-color: #FC4C02;
    background: #fff5f2;
    border-width: 4px;
    transform: scale(1.02);
}

#dropZone .icon {
    font-size: 64px;
    margin-bottom: 20px;
    opacity: 0.5;
}

#dropZone h2 {
    color: #333;
    margin-bottom: 15px;
    font-size: 24px;
}

#dropZone p {
    color: #666;
    font-size: 16px;
    margin-bottom: 20px;
}

/* ============================================
   File Input
   ============================================ */
#fileInput {
    display: none;
}

/* ============================================
   Button
   ============================================ */
.btn {
    display: inline-block;
    padding: 12px 30px;
    background: #FC4C02;
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

.btn:hover {
    background: #e63d00;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(252, 76, 2, 0.3);
}

/* ============================================
   Status Messages
   ============================================ */
#status {
    margin-top: 20px;
    padding: 15px;
    border-radius: 10px;
    text-align: center;
    font-weight: 500;
    display: none;
}

#status.success {
    background: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

#status.error {
    background: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

#status.info {
    background: #d1ecf1;
    color: #0c5460;
    border: 1px solid #bee5eb;
}

/* ============================================
   Chart Container
   ============================================ */
#chartContainer {
    margin-top: 40px;
    display: none;
    animation: fadeIn 0.5s ease;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

#powerCurveChart {
    max-height: 600px;
}

/* ============================================
   Statistics
   ============================================ */
.stats {
    display: none;
    margin-top: 30px;
    padding: 20px;
    background: #f8f9fa;
    border-radius: 10px;
}

.stats h3 {
    color: #333;
    margin-bottom: 15px;
    font-size: 20px;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 15px;
}

.stat-item {
    background: white;
    padding: 15px;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.stat-label {
    color: #666;
    font-size: 12px;
    font-weight: 600;
    text-transform: uppercase;
    margin-bottom: 5px;
}

.stat-value {
    color: #FC4C02;
    font-size: 24px;
    font-weight: 700;
}

/* ============================================
   Footer
   ============================================ */
footer {
    margin-top: 40px;
    text-align: center;
    color: #999;
    font-size: 14px;
}