style.css

:root{

    /* dark theme color scheme */

    --font-family: Verdana, Geneva, Tahoma, sans-serif;
    --dark-background: #292D36;
    --dark-footer-container-bg: #2A2C37;
    --footer-box-shaodw: 2px 2px 12px 2px rgb(150 150 150 / 10%);
    --box-shadow: 2px 12px 12px 12px rgba(179, 179, 179, 0.2);
    --container-border-radius: 40px;
    --footer-container-radius: 20px;
    --normal-box-shadow: 2px 2px 2px 2px rgba(0, 0, 0, 0.2);
    --dark-color-theme: #fff;
    --dark-btn-bg: #212225;
    --dark-btn-pimary-operator: turquoise;
    --dark-btn-secodnary-operator: orange;
    --footer-bg-light: #fff;

    /* light color scheme */
    --light-bg: #fff;
    --light-footer-bg: #fff;
    --light-font-color-theme: #292D36;
    --footer-line-bg: var(--dark-background);

    --main-bg: url(https://images.unsplash.com/photo-1472289065668-ce650ac443d2?ixlib=rb-4.0.3&ixid=MnwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8&auto=format&fit=crop&w=869&q=80);
}

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

body{
    background: var(--main-bg);
    background-repeat: no-repeat;
    background-size:cover;
    background-position: center;
}
/* main container */
.container {
    margin: 100px auto;
   
}
/* main calculator */
.calculator {
    margin: auto;
    background-color: var(--dark-background);
    color: white;
    width: 340px;
    border-radius: 15px;
    box-shadow: var(--normal-box-shadow);
}

/* calculator head part */
.header {
    display: flex;
    justify-content: space-around;
    padding: 10px;
}

/* time  */
.header .time {
    align-self: left;
    padding: 0px 20px;
    width: 50%;
    font-family: var(--font-family);
    opacity: 0.9;

}

/* top right icons  */
.header .other-right-icons {
    opacity: 0.7;
    width: 50%;
    display: flex;
    justify-content: space-evenly;

}

.header .body_Upper.fa-moon p .fa-sun{
    cursor: pointer;
}
/* calculator body */

.body_Upper {
    display: flex;
    justify-content: center;
    padding: 15px;
    background-color: var(--dark-background);
    color: white;
    width: 20%;
    margin: 30px auto;
    border-radius: 8px;
    box-shadow: 2px 2px 2px 2px rgba(0, 0, 0, 0.2);
}

/* calculator moon and sun icon*/
.body_Upper i {
    margin: 0px 10px;
    opacity: 0.7;
    cursor: pointer;
}

/* output */
.body_center_output {
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    padding: 15px;
    margin: 0px 20px;
    font-family: Verdana, Geneva, Tahoma, sans-serif;

}

.body_center_output #inputText{
    background: none;
    outline: none;
    /* border-radius: var(--container-border-radius); */
    padding: 10px;
    border: none;
    display: flex;
    justify-content: flex-end;
    font-size: 2.5rem;
    width: 100%;
}

.body_center_output p,
h2 {
    margin: 12px 0px;
}

.body_center_output p {
    opacity: 0.8;
}

.body_center_output p>span {
    color: var(--dark-btn-pimary-operator);
    opacity: 0.7;
}

/* footer Part Calculator Container and Buttons */

.footer {
    display: flex;
    flex-direction: column;
    justify-content: center;
    background-color: var(--footer-container-bg);
    box-shadow: var(--footer-box-shaodw);
    padding: 30px;
    border-radius: 40px 40px 17px 21px;


}

/* calculator buttons */
.footer button {
    background-color: var(--dark-btn-bg);
    width: 10%;
    font-family: Verdana, Geneva, Tahoma, sans-serif;
    font-size: 14px;
    padding: 10px;
    margin: 10px auto;
    border: none;
    border-radius: 2px;
    box-shadow: 2px 2px 2px 2px rgba(0, 0, 0, 0.2);
    color: white;
    cursor: pointer;
}

.footer .row_1 p {
    /* background-color: #343435; */
    color: var(--dark-btn-pimary-operator);
    padding: 10px;
    margin: 10px auto;
    box-shadow: 2px 2px 2px 2px rgba(0, 0, 0, 0.2);
    border-radius: 7px;

}

.row_1 p{
    cursor: pointer;
}

.footer .row_1 button {
    color: orange;
}

.footer .row_5 button {
    color: var(--dark-btn-secodnary-operator);
}

.footer .row_2,
.row_3,
.row_4,
.row_5 {
    display: flex;
    justify-content: space-around;
}

.footer .row_1 {
    display: flex;
    justify-content: space-around;
}

.row_6 {
    width: 50%;
    height: 100px;
    justify-content: center;
    display: block;
    justify-content: center;
    margin-top: 40px;
    margin-left: auto;
    margin-right: auto;
    box-shadow: var(--box-shadow);
    height: 5px;
    background: white;
    border-radius: 10px;
    opacity: 0.1;
}