* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
body {
    font-family: Arial, Helvetica, sans-serif;
    height: 100vh;      
    display: flex;
    flex-direction: column;  
}

/* toolbar */
.toolbar {
    display: flex;
    align-items: center;
    width: 100%;
    gap: 55px;
    padding: 10px 15px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    border-radius: 0 0 10px 10px;
    background: white;
    flex-shrink: 0;          
}

.separator {
    display: inline-block;    
    width: 1.5px;               
    height: 30px;             
    background-color: rgb(125, 125, 125);;   
}

.toolbar select {
    margin: 0px 5px;
    cursor: pointer;
    padding: 5px;
    border-radius: 8px;
}
.toolbar i {
    margin: 0px 5px;
    cursor: pointer;
    padding: 5px;
    border-radius: 5px;
    font-size: 1.2rem;
}
.toolbar i:hover {
    color: #4a90e2;
    transform: scale(1.2);
    transition: 0.3s;
}

/* formula bar */
.formula-bar {
    display: flex;
    align-items: center;
    background: #e8e8e8;
    border: 1px solid #ccc;
    padding: 5px;
    margin: 0 8px;
    border-radius: 8px;
    height: 35px;
    gap: 10px;
    flex-shrink: 0;      
}
.tool-img{
    height: 20px;
    width: 20px;
}
.separator1 {
    width: 1.5px;
    height: 20px;
    background: rgb(125, 125, 125);
    margin-top: 5px;
    margin-bottom: 3px;
    display: inline-block;
}

.address-input {
    border: 1px solid #ccc;
    background: white;
    text-align: center;
    font-weight: bold;
    width: 70px;
    border-radius: 5px;
    padding: 2px;
}
.formula-input {
    flex: 1;
    border: 1px solid #ccc;
    font-size: 13px;
    padding: 3.5px;
    border-radius: 5px;
}

/* sheets */
.sheets {
    display: flex;
    align-items: center;
    padding: 10px;
    background: white;
    border: 1px solid #ddd;
    flex-shrink: 0;      
}
.sheets-list{
    display: flex;
    height: 100%;
    overflow-x: auto;
}
.add-sheet {
    background: #4a90e2;
    color: white;
    border: none;
    cursor: pointer;
    margin-right: 10px;
    padding: 5px 12px;
    border-radius: 5px;
}

.sheet {
    background: white;
    margin: 0 5px;
    padding: 5px 12px;
    border-radius: 5px;
    cursor: pointer;
}

.active-sheet {
    background: #4a90e2;
    color: white;
}

/* grid */
.grid-container {
    margin-top:5px;
    flex: 1;              
    overflow: auto;       
    position: relative;
}
.top_left_cell {
    height: 1.4rem;
    width: 2rem;
    border-right: 2px solid lightgray;
    border-bottom: 2px solid lightgray;
}
.top_row {
    display: flex;
    position: relative;
    left: 2rem;
    top: -1.4rem;
}
.top_row .cell {
    text-align: center;
    min-width: 5rem;
    padding-top: 0.21rem;
    font-size: 0.7rem;
    border: 1.5px solid rgb(100, 99, 99);
    background-color: #b4bad3;
}
.left_col {
    width: 2rem;
    text-align: center;
    position: relative;
    top: -1.45rem;
    background-color: #b4bad3;
}
.left_col > .cell {
    padding-top: 5px;
    font-size: 10px;
}
.row {
    display: flex;
}
.cell {
    border:0.1px solid gray;
    height:1.4rem;
    text-align: center;
    outline:none;
    border-right:none;
    border-top:none;
}
.grid .cell {
    min-width: 5rem;
    /* border: 1px solid rgb(160, 158, 158); */
    border-top: none;
    border-right: none;
}
.grid {
    position: absolute;
    top: 1.35rem;
    left: 2rem;
}

.selected{
    border-radius: 50%;
    background: rgba(52, 152, 219, 0.2); /* subtle highlight */
    box-shadow: 1 1px 1px rgba(52, 152, 219, 0.3);
}