/* Font selected from google fonts- popins (medium) -> we have copied import link ( also available-> link type).. */
@import url('https://fonts.googleapis.com/css2?family=Oswald:wght@200..700&family=Poppins:ital,wght@0,100;0,200;0,300;0,400;0,500;0,600;0,700;0,800;0,900;1,100;1,200;1,300;1,400;1,500;1,600;1,700;1,800;1,900&display=swap');
*{
    margin: 0;  /* make Initial margin of all elements = 0 */
    padding: 0;
    box-sizing: border-box;  /* Add margin and padding of elements inside its total heigth and width */
    font-family: 'poppins' , sans-serif;  /* if not found popins font(imported above), then fallback to sans-sarif */
}

body{
    width: 100vw;
    height: 100vh;

    /* calculator(box) in center of body */
    display: flex;
    justify-content: center;
    align-items: center;

    /* for mixture of colors say 2 colors  */
    background: linear-gradient(-60deg, #010422, #1a2582);background: linear-gradient(angle, color-stop1, color-stop2); OR background: linear-gradient(direction(to top, to bottom right etc), color-stop1, color-stop2, ...);
}

.calculator{
    /* Take width as per content */
    width: auto;  /* No need :Bcz it is by-default */
    border: 1px solid #457b9d;
    padding: 1.5rem;  /* rem: relative to the font-size of the root element (most browsers = 16px (=1rem) ) */
    border-radius: 1rem ;
    background: transparent;
    box-shadow: 0px 3px 20px 8px rgba(115, 117, 123,.3);
        /* x(+right)  y(+ve down)  blur-radius  spread(optional)  color  */
}

input{
    width: 20rem;  /* wrt parent (22rem = 352px if browser font = 16px).  */
    border: none;
    outline: none;
    padding: 1rem;
    margin: 0.5rem;
    text-align: right;
    font-size: 2rem;
    background: transparent;
    box-shadow: 0px 3px 15px rgba(85, 84, 84, 0.1);
    cursor: pointer;
    color: #ffffff; /* what we click , text color = white */
}

input::placeholder{  /* <input> kay placeholder attribute ki CSS 
    -> :: -> A pseudo-element(like before, after etc pseudo element) used to style the placeholder text of an input field.*/
    color: #ffffff;
}

button{
    border: none;
    width: 4rem ;  /* we made width= 20rem of input above, so here we have 4 buttons on each row , make 5 rem each to adjust accordingly */
    height: 4rem;
    border-radius: 50%;  /* make buttons circular */
    margin: 0.4rem;
    font-size: 1.5rem;
    background:transparent;
    color: #ffffff;
    box-shadow: -5px -5px 15px rgba(255, 255, 255, 0.074);
    cursor: pointer;
}

/* for = button bcz iot shows result  */
.equal-btn{
    background-color: #5C469C;
    font-size: 2.2rem;
}

.operator-btn{
    color:#D4ADFC ;
}