* {
    box-sizing: border-box;
    touch-action: manipulation;
}

html {
    background-color: black;
    height: 100%;
}

body {
  height: 100%;
  overflow: hidden;
  padding-bottom: 100px;
}

@media (max-width: 768px) {  /* adjust the breakpoint as needed */
  body #reckoner {
    width: 93%;
    height: 70%;
  }
  body #display {
    width: 100%;
    height: 35%;
  }
  body #display span {
    font-size: 3rem;
  }
  body #buttons {
    width: 100%;
    height: 100%;
    gap: 2%;
  }
  body #buttons > div {
    width: 100%;
    height: 100%;
    gap: 3%;
  }
  body #buttons button {
    width: 100%;
    height: 100%;
    font-size: 2.5rem;
  }
  body .img {
    max-height: 9vmin;
  }
}

#buttons .operator {
    background-color: #FF9500;
    color: black;
}

.highlight{
    background-color: rgb(255, 115, 0) !important; /* darker shade of orange */
    box-shadow: 0 0 8px rgba(241, 144, 0, 0.7), inset 0 2px 4px rgba(0,0,0,0.3) !important;
    transform: scale(0.97) !important;
    transition: all 0.15s ease-in-out !important;
}

#buttons .function {
    background-color: #696969;
    color: black;
}

#buttons button:active {
  transform: scale(0.95); /* gives a "press down" effect */
  background-color: #d97800; /* slightly darker orange */
  box-shadow: inset 0 2px 6px rgba(0, 0, 0, 0.4); /* inner shadow for depth */
}

.img {
    max-height: 4vmin;
}

body {
    margin: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100vh;
}

#backspace-img {
    display: none;
}

#reckoner {
    display: flex;
    flex-direction: column;
    align-items: center;

    background: #111;
    border-radius: 12px;
    padding: 1rem;
    border: 1px solid rgba(255,255,255,0.06);
    box-shadow:
        0 0 20px rgba(241,144,0,0.25),
        0 0 40px rgba(241,144,0,0.15),
        inset 0 1px 0 rgba(255,255,255,0.02);
}

#display {
    width: 100%;
    height: 15vmin;
    margin: 0 0 3% 0;
    display: flex;
    align-items: center;
    font-family: 'Roboto Mono', monospace;

    background: rgba(255,255,255,0.03);
    border-radius: 12px;
    padding: 1rem;
    border: 1px solid rgba(255, 255, 255, 0.06);
    box-shadow: 
        inset 0 0 15px rgba(241,144,0,0.25),
        inset 0 0 30px rgba(241,144,0,0.15),
        inset 0 1px 0 rgba(255,255,255,0.03);

}

#display span {
    color: azure;
    flex: 1 1 0;
    margin: 5%;
    font-size: 5vmin;
    min-width: 0;
    direction: rtl;
    overflow: hidden;
}

#buttons {
    display: flex;
    flex-direction: column;
    gap: 0.7vmin;
}

#buttons > div {
    display: flex;
    gap: 0.5vmin;
    width: 40vmin;
}

#buttons button {
    color: white;
    background-color: #333;

    border-width: 1px;
    border-color: transparent;
    border-radius: 20px;

    flex: 1 1 0px;
    font-size: 5vmin;
    min-width: 0;
    display: flex;
    align-items: center;
    justify-content: center;
}