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

body {
    font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    background-color: var(--bg-color, #e0e0e0);
}

section {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    width: 100%;
}

.container {
    background: #fdfdfd;
    padding: 25px;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.15);
    max-width: 400px;
    width: 90%; 
}

h1 {
    text-align: center;
    margin-bottom: 20px;
    color: #333;
    font-weight: 300;
}

.main-table {
    width: 100%;
    border-collapse: collapse;
    border-spacing: 0;
}

.main-table td {
    padding: 6px;
}

.display {
    width: 100%;
    height: 60px;
    font-size: 2.2rem;
    text-align: right;
    border: none;
    border-radius: 10px;
    padding: 10px 20px;
    margin-bottom: 15px;
    background-color: #2c2c2c;
    color: white;
}

.buttons {
    width: 100%;
    height: 60px;
    font-size: 1.5rem;
    border: none;
    border-radius: 10px;
    cursor: pointer;
    background-color: #f0f0f0;
    transition: all 0.2s ease-in-out;
}

.buttons:hover {
    background-color: #ddd;
    transform: translateY(-2px); 
}

.button-eq {
    background-color: var(--eq-bg-color, #ff9500);
    color: white;
}

.button-eq:hover {
    background-color: #e08500;
}