body {
    font-family: "Poppins", sans-serif;
    background: linear-gradient(135deg, #6a11cb, #2575fc);
    height: 100vh;
    margin: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
}

.container {
    text-align: center;
    background: rgba(255, 255, 255, 0.1);
    padding: 40px 60px;
    border-radius: 16px;
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.2);
    backdrop-filter: blur(10px);
    max-width: 520px;
}

h1 {
    font-size: 1.6em;
    margin-bottom: 20px;
    letter-spacing: 1px;
}

.note-selection {
    margin: 20px 0;
}

.note-selection select {
    padding: 10px;
    font-size: 1em;
    border-radius: 8px;
    border: none;
}

.scale-display {
    font-size: 1.2em;
    margin-top: 20px;
}

.chord-info {
    margin-top: 20px;
    font-size: 1em;
    line-height: 1.5;
}

button {
    background-color: #fff;
    color: #2575fc;
    border: none;
    padding: 10px 18px;
    font-size: 1.0em;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.18s ease;
}

button:hover {
    background-color: #2575fc;
    color: #fff;
    transform: scale(1.03);
}