:root {
    --primary: #2563eb;
    --bg: #f8fafc;
    --card-bg: #ffffff;
    --text: #1e293b;
    --border: #e2e8f0;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Arial, sans-serif;
    background-color: var(--bg);
    color: var(--text);
    margin: 0;
    padding: 40px 20px;
    display: flex;
    justify-content: center;
}

.calculator-container {
    width: 100%;
    max-width: 850px;
    background: var(--card-bg);
    padding: 30px;
    border-radius: 12px;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
}

h2 {
    margin-top: 0;
    color: var(--text);
    font-size: 24px;
    margin-bottom: 24px;
}

.toggle-container {
    display: flex;
    background: var(--bg);
    padding: 4px;
    border-radius: 8px;
    margin-bottom: 24px;
    border: 1px solid var(--border);
}

.toggle-btn {
    flex: 1;
    background: none;
    border: none;
    padding: 12px;
    font-size: 14px;
    font-weight: 600;
    color: #64748b;
    cursor: pointer;
    border-radius: 6px;
    transition: all 0.2s ease;
}

.toggle-btn.active {
    background: var(--card-bg);
    color: var(--primary);
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

.input-group {
    margin-bottom: 24px;
}

label {
    display: block;
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 8px;
}

input[type="number"] {
    width: 100%;
    padding: 12px;
    border: 1px solid var(--border);
    border-radius: 6px;
    font-size: 16px;
    box-sizing: border-box;
}

input:focus {
    outline: 2px solid var(--primary);
    outline-offset: -1px;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 10px;
    text-align: left;
}

th {
    background-color: var(--bg);
    color: #64748b;
    font-size: 13px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    padding: 12px 16px;
    border-bottom: 2px solid var(--border);
}

td {
    padding: 16px;
    border-bottom: 1px solid var(--border);
    font-size: 15px;
}

tr:last-child td {
    border-bottom: none;
}

.bold-text {
    font-weight: 600;
}