:root {
    /* Dark mode (default) */
    --background: #1a1a1a;
    --calculator-bg: #2a2a2a;
    --table-header-bg: #333;
    --input-bg: #444;
    --text: #fff;
    --stake-color: #fff;
    --label-color: #fff;
    --message-color: #fff;
    --attribution-color: #888;
    --border-color: #444;
    --profit-positive: #0f0; /* Green for dark mode */
}

body.light-mode {
    /* Light mode */
    --background: #f0f0f0;
    --calculator-bg: #e0e0e0;
    --table-header-bg: #d0d0d0;
    --input-bg: #ccc;
    --text: #000;
    --stake-color: #000;
    --label-color: #000;
    --message-color: #000;
    --attribution-color: #666;
    --border-color: #999;
    --profit-positive: #008000; /* Darker green for light mode */
}

body {
    font-family: Arial, sans-serif;
    background-color: var(--background);
    color: var(--text);
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 20px;
    margin: 0;
    transition: background-color 0.3s, color 0.3s;
}

.calculator {
    background-color: var(--calculator-bg);
    padding: 20px;
    border-radius: 8px;
    transition: background-color 0.3s;
}

.controls {
    display: flex;
    justify-content: space-between;
    margin-bottom: 10px;
}

button {
    background-color: var(--input-bg);
    color: var(--text);
    border: none;
    padding: 5px 10px;
    border-radius: 4px;
    cursor: pointer;
    margin-right: 5px;
    transition: background-color 0.3s, color 0.3s;
}

button:hover {
    background-color: #555; /* Slightly darker for dark mode */
}

body.light-mode button:hover {
    background-color: #bbb; /* Slightly darker for light mode */
}

.details {
    display: flex;
    justify-content: space-between;
    margin-bottom: 10px;
}

.details div {
    display: flex;
    align-items: center;
}

.details label {
    margin-right: 5px;
    color: var(--label-color);
    transition: color 0.3s;
}

.details input[type="text"] {
    background-color: var(--input-bg);
    color: var(--text);
    border: none;
    padding: 5px;
    border-radius: 4px;
    width: 200px;
    transition: background-color 0.3s, color 0.3s;
}

table {
    width: 100%;
    border-collapse: collapse;
}

th, td {
    padding: 10px;
    text-align: center;
    border-bottom: 1px solid var(--border-color);
    transition: border-bottom 0.3s;
}

th {
    background-color: var(--table-header-bg);
    transition: background-color 0.3s;
}

input[type="number"] {
    background-color: var(--input-bg);
    color: var(--text);
    border: none;
    padding: 5px;
    border-radius: 4px;
    width: 80px;
    transition: background-color 0.3s, color 0.3s;
}

select {
    background-color: var(--input-bg);
    color: var(--text);
    border: none;
    padding: 5px;
    border-radius: 4px;
    transition: background-color 0.3s, color 0.3s;
}

input[type="checkbox"] {
    margin: 0;
}

/* Stake values */
.stake-value {
    color: var(--stake-color);
    transition: color 0.3s;
}

/* Return and profit values with color coding */
.return-value, .profit-value {
    color: var(--profit-positive); /* Default to green */
}

/* Color classes for return/profit */
.profit-positive {
    color: var(--profit-positive);
}
.profit-negative {
    color: #ff5555; /* Lighter red for readability */
}
.profit-zero {
    color: #888; /* Grey */
}

.options {
    margin-top: 10px;
    text-align: left;
}

.options label {
    margin-right: 10px;
}

.summary {
    margin-top: 10px;
    text-align: right;
}

.summary .label {
    color: var(--label-color);
    transition: color 0.3s;
}

.summary span {
    margin-left: 10px;
}

.message {
    margin-top: 10px;
    text-align: center;
}

.message span {
    color: var(--message-color);
    font-size: 14px;
    transition: color 0.3s;
}

.attribution {
    margin-top: 20px;
    font-size: 14px;
    color: var(--attribution-color);
    transition: color 0.3s;
}