.usm-container {
    max-width: 400px;
    margin: 20px auto;
    padding: 25px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 20px;
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.2);
    color: white;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

.usm-header {
    text-align: center;
    margin-bottom: 20px;
}

.usm-header h3 {
    margin: 0 0 10px 0;
    font-size: 24px;
    font-weight: 600;
}

.usm-status {
    margin: 0;
    font-size: 14px;
    opacity: 0.9;
    min-height: 20px;
}

.usm-controls {
    text-align: center;
    margin: 25px 0;
}

.usm-btn {
    padding: 12px 24px;
    margin: 0 10px;
    border: none;
    border-radius: 50px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.usm-btn-primary {
    background: linear-gradient(45deg, #ff6b6b, #ee5a24);
    color: white;
    box-shadow: 0 4px 15px rgba(255, 107, 107, 0.4);
}

.usm-btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(255, 107, 107, 0.6);
}

.usm-btn-secondary {
    background: linear-gradient(45deg, #74b9ff, #0984e3);
    color: white;
    box-shadow: 0 4px 15px rgba(116, 185, 255, 0.4);
}

.usm-btn-secondary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(116, 185, 255, 0.6);
}

.usm-speedometer {
    position: relative;
    margin: 30px auto;
}

.usm-gauge {
    position: relative;
    width: 250px;
    height: 250px;
    margin: 0 auto;
    background: radial-gradient(circle at center, #2d3436 0%, #1a1a1a 100%);
    border-radius: 50%;
    border: 8px solid #34495e;
    box-shadow: 
        inset 0 0 20px rgba(0, 0, 0, 0.8),
        0 10px 30px rgba(0, 0, 0, 0.4);
}

.usm-gauge-background {
    position: absolute;
    width: 100%;
    height: 100%;
    border-radius: 50%;
    background: conic-gradient(
        #00b894 0deg 90deg,
        #fdcb6e 90deg 150deg,
        #e17055 150deg 180deg,
        #d63031 180deg 270deg,
        #6c5ce7 270deg 360deg
    );
    opacity: 0.3;
}

.usm-needle {
    position: absolute;
    width: 3px;
    height: 100px;
    background: linear-gradient(to top, #ff0000, #ff6b6b);
    top: 25px;
    left: 50%;
    transform-origin: bottom center;
    transform: rotate(0deg);
    transition: transform 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
    border-radius: 3px;
    z-index: 10;
    box-shadow: 0 0 10px rgba(255, 0, 0, 0.5);
}

.usm-center-circle {
    position: absolute;
    width: 20px;
    height: 20px;
    background: #ff0000;
    border-radius: 50%;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    z-index: 11;
    box-shadow: 0 0 10px rgba(255, 0, 0, 0.8);
}

.usm-speed-display {
    position: absolute;
    top: 65%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 32px;
    font-weight: bold;
    color: white;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.5);
    z-index: 12;
}

.usm-unit {
    position: absolute;
    top: 78%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 14px;
    color: #bdc3c7;
    z-index: 12;
}

.usm-speed-stats {
    display: flex;
    justify-content: space-around;
    margin-top: 30px;
    background: rgba(255, 255, 255, 0.1);
    padding: 15px;
    border-radius: 15px;
    backdrop-filter: blur(10px);
}

.usm-stat {
    text-align: center;
}

.usm-stat-label {
    display: block;
    font-size: 12px;
    opacity: 0.8;
    margin-bottom: 5px;
}

.usm-stat-value {
    display: block;
    font-size: 18px;
    font-weight: bold;
    color: #fdcb6e;
}

.usm-footer {
    margin-top: 20px;
    text-align: center;
}

.usm-accuracy {
    font-size: 12px;
    opacity: 0.8;
}

.usm-accuracy-label {
    margin-right: 5px;
}

/* Animation for speed changes */
@keyframes pulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.05); }
    100% { transform: scale(1); }
}

.usm-speed-pulse {
    animation: pulse 0.3s ease-in-out;
}

/* Responsive design */
@media (max-width: 480px) {
    .usm-container {
        margin: 10px;
        padding: 20px;
    }
    
    .usm-gauge {
        width: 200px;
        height: 200px;
    }
    
    .usm-needle {
        height: 80px;
        top: 20px;
    }
    
    .usm-speed-display {
        font-size: 28px;
    }
}