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

@font-face {
    font-family: 'Digital7';
    src: url(./fonts/digital-7.ttf) format('truetype');
    font-weight: normal;
    font-style: normal;
}

:root {
    --background: rgb(175, 187, 192);
    --screen:rgb(38, 104, 38);
    --text:rgb(0, 0, 0);
    --buttonText: rgb(255, 255, 255);
    --bottonColor: rgb(57, 61, 65);
    --buttonAlternate: rgb(153, 0, 0);
}

body {
    background: black;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
}

.calculator {
    background: var(--background);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    width: 350px;
    border-radius: 1rem;
    box-shadow: 2px 2px rgba(0, 0, 0, 0.5),inset 2px 2px  rgb(218, 221, 223);

}

.screen {
    font-size: 4rem;
    width: 90%;
    border-radius: 1rem;
    text-align: right;
    padding: 1.2rem;
    background: var(--screen);
    margin: 1.6rem;
    box-shadow: inset 2px 2px 5px rgba(0, 0, 0, .6);
}

.output {
    font-family: 'Digital7', sans-serif;
    font-size: 4.7rem;
}

.button-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    grid-template-rows: repeat(5, 1fr);
    gap: .8rem;
    padding: 1.2rem;
   width: 100%;
}

.button-grid button {
    justify-content: center;
    border-radius: 10px;
    border: none;
    background: var(--bottonColor);
    color: var(--buttonText);
    box-shadow: 2px 2px rgba(0, 0, 0, 0.3),inset 2px 2px  rgb(255, 255, 255);
    padding: .9rem;
    font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    font-size: 1.2rem;
}

.button-grid button.extra,
.button-grid button.extraO {
    background: var(--buttonAlternate);
}


.button-grid button:active,
.button-grid button.boton-pulsado {
    transform: translateY(4px) !important;
    box-shadow: 0 0 transparent !important;
}

.memories {
    width: 100%;
    display: flex;
    justify-content: space-between;
    gap: .5rem;
    padding-inline: 1.2rem;
}

.mem {
    flex: 1; 
    border: none;
    border-radius: .4rem;
    box-shadow: 2px 2px rgba(0, 0, 0, 0.3),inset 2px 2px  rgb(255, 255, 255);
}