*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
body {
    height: 100vh;
    width: 100vw;
    background-color: #121212;
    color: #E0E0E0;
    overflow: hidden;
}
body::after, body::before {
    content: '';
    height: 100%;
    width: 100%;
    position: absolute;
    z-index: -10;
    top: 0;
    left: 0;
    background: radial-gradient(circle, rgba(0, 255, 255, 1) 30%, rgba(0, 255, 255, 0.3) 80%);
    clip-path: circle(30% at 10% 10%);
}
body::before {
    clip-path: circle(30% at 90% 90%);
}
.flex, .box input, .in input, #out, .work-bench, .opt-btn, .opt-btn span:first-child, .row button, .row {
    display: flex;
    align-items: center;
}

/* header of the page */
.header {
    justify-content: space-between;
    padding: 0.75rem 5rem;
    min-height: 4rem;
    width: 100%;
    background: #1A1A1A;
    box-shadow: 0px 0px 11px rgb(0, 0, 0);
}

/* left part of header */
.left {
    justify-content: center;
    gap: 1rem;
    cursor: default;
}
.left i {
    font-size: 2.5rem;
    color: #00FFFF;
}
.left span {
    font-family: 'Baloo Thambi 2', sans-serif;
    font-size: 1.5rem;
    font-weight: 800;
    color: #E0E0E0;
    text-shadow: 0 0 3px #00ffff;
}

/* right part of header */
.right, .link-box, .btns {
    justify-content: center;
    gap: 2rem;
}
.link-box a {
    font-family: 'Baloo Thambi 2', sans-serif;
    color: #E0E0E0;
    text-decoration: none;
    font-size: 1rem;
    transition: all 0.2s ease-in-out;
}
.link-box a:hover {
    font-weight: 600;
    color: #00ffff;
    scale: 1.05;
}
.btns {
    display: none;
}

/* main-section of the webpage */
.work-bench {
    height: calc((100vh - 64px));
    width: 100%;
    align-items: flex-start;
    justify-content: space-between;
    position: relative;
}
.dailogBG {
    display: none;
}

/* slider choices section */
.options {
    justify-content: center;
    height: 100%;
    min-width: 21rem;
    padding: 1rem;
    position: static;
    transition: all 0.3s ease-in-out;
}
.inner-box {
    height: 100%;
    width: 100%;
    background: #1A1A1A;
    box-shadow: 0 0 18px #000000;
    border-radius: 1.5rem;
    justify-content: space-between;
    flex-direction: column;
    padding: 0.5rem;
    gap: 1rem;
    overflow-x: hidden;
    overflow-y: scroll;
}
.inner-box p {
    font-family: 'Baloo Thambi 2', sans-serif;
    font-size: 0.75rem;
    opacity: 0.5;
}
.choices {
    width: 100%;
    justify-content: space-around;
    flex-direction: column;
    gap: 2rem;
    padding: 0.5rem 1rem;
}
.opt-btn {
    justify-content: start;
    gap: 0.5rem;
    padding: 0.75rem;
    border-radius: 0.5rem;
    width: 100%;
    background-color: #333333;
    box-shadow: 0 0 9px #000000;
    border: none;
    color: #E0E0E0;
    cursor: pointer;
    transition: all 0.2s ease-in-out;
}
.opt-btn span:first-child {
    width: 3rem;
    justify-content: center;
    font-size: 1.5rem;
}
.opt-btn span:last-child {
    font-family: 'Baloo Thambi 2', sans-serif;
    font-size: 1rem;
    transition: all 0.2s ease-in-out;
}
.opt-btn:hover span:last-child, .btnToggler span:last-child {
    font-weight: 800;
}
.btnToggler {
    box-shadow: 0 0 9px #00ffff;
    background-color: #00FFFF;
    color: #121212;
    scale: 1.05;
}

/* calculator devices section */
.device {
    padding: 1rem;
    width: 100%;
    height: 100%;
    justify-content: center;
    position: relative;
}

/* calculators */
.calcy {
    width: fit-content;
    position: absolute;
    background: #121212;
    padding: 1.5rem;
    border-radius: 1.5rem;
    gap: 2.5rem;
    justify-content: center;
    flex-direction: column;
    scale: 0;
    box-shadow: 0 0 18px #00ffff;
    transition: all 0.5s ease-in-out;
}

/* arithmetic calculator components */
.screen {
    width: 19rem;
    height: 4rem;
    background: #00ffff;
    border: 2px solid rgba(0, 255, 255, 0.3);
    border-radius: 1rem;
    box-shadow: inset -3px 5px 9px #000000;
    flex-direction: row-reverse;
    padding: 1rem;
    font-size: 2rem;
    font-family: 'Baloo Thambi 2', sans-serif;
    font-weight: 800;
    color: #121212;
    overflow-x: scroll;
    overflow-y: hidden;
}
.screen::-webkit-scrollbar, .inner-box::-webkit-scrollbar {
    display: none;
}
.keypad {
    justify-content: center;
    flex-direction: column;
    width: 100%;
    gap: 0.75rem;
}
.row {
    justify-content: space-between;
    gap: 1.25rem;
    width: 100%;
}
.row button {
    font-size: 1.75rem;
    font-weight: 700;
    font-family: 'Baloo Thambi 2', sans-serif;
    justify-content: center;
    height: 3.5rem;
    background-color: #333333;
    box-shadow: 0 0 9px #000000;
    border: none;
    color: #E0E0E0;
    cursor: pointer;
    border-radius: 1rem;
    width: 3.5rem;
    transition: all 0.1s ease-in-out;
}
.row button:hover, #bmi-gen:hover, #gen:hover {
    box-shadow: 0 0 9px #00ffff;
    background-color: #1A1A1A;
}
.row button:active, #bmi-gen:active, #gen:active {
    box-shadow: 0 0 9px #000000;
    background-color: #1A1A1A;
    scale: 0.92;
}
#equal {
    width: 8.6rem;
    background-color: #00ffff;
    color: #121212;
}

/* bmi and unit convertor components */
#bmi-gen, #gen {
    font-size: 1rem;
    font-family: 'Baloo Thambi 2', sans-serif;
    font-weight: 800;
    border-radius: 0.75rem;
    border: none;
    padding: 0.5rem 2rem;
    background-color: #333333;
    box-shadow: 0 0 9px #000000;
    color: #E0E0E0;
    cursor: pointer;
    transition: all 0.1s ease-in-out;
}
.bmi-out, .result {
    width: 100%;
    font-family: "Baloo Thambi 2", sans-serif;
    padding: 0.5rem 1rem;
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
    font-size: 0.9rem;
    font-weight: 600;
    border-radius: 0.75rem;
    background: rgba(0, 255, 255, 0.1);
    box-shadow: 0 0 9px #00ffff;
}
.swap {
    height: 2.5rem;
    width: 2.5rem;
    border-radius: 50%;
    border: 2px solid #00ffff;
    justify-content: center;
    margin: auto;
    box-shadow: 0 0 9px #00ffff;
    color: #00FFFF;
}

/* input components */
.input-box {
    display: flex;
    gap: 1rem;
    flex-direction: row;
    width: 100%;
    font-family: 'Baloo Thambi 2', sans-serif;
}
.box, .in, .out {
    display: flex;
    gap: 0.5rem;
    flex-direction: column;
    width: 19rem;
}
.box input, .in input, #out {
    font-family: 'Baloo Thambi 2', sans-serif;
    height: 3rem;
    background: rgb(0, 0, 0, 0.5);
    border-radius: 0.75rem;
    border: 2px solid rgba(0, 255, 255, 0.3);
    padding: 0.5rem;
    color: #fff;
    background: #00ffff;
    box-shadow: inset -3px 5px 9px #000000;
    font-weight: 600;
    color: #121212;
    font-size: 1.25rem;
}
.box input::placeholder, .in input::placeholder {
    font-size: 1rem;
    color: #121212;
}

/* selection components */
.select-box {
    font-family: 'Baloo Thambi 2', sans-serif;
    font-size: 1rem;
    width: 100%;
    border-radius: 0.5rem;
    background-color: #333333;
    color: #e0e0e0;
    border: none;
    padding: 0.5rem;
    font-weight: 600;
    cursor: pointer;
}
select.select-box option {
    background-color: rgba(0, 255, 255, 0.3);
    color: #121212;
    font-weight: 600;
    cursor: pointer;
}
select.select-box option:checked {
    background-color: #121212;
    color: #e0e0e0;
}
select.select-box::-webkit-scrollbar {
    background-color: rgba(0, 255, 255, 0.3);
    width: 6px;
}
select.select-box::-webkit-scrollbar-thumb {
    background-color: #121212;
    border-radius: 6px;
}