:root {
    --primary-color: #2E5BFF;
    --accent-color: #829dff;
    --text-color: #333333;
    --bg-main: #ffffff;
    --bg-secondary: #fafafa;
    --bg-third: #f5f5f5;
}

body {
    font-family: Arial, sans-serif;
    background-color: var(--bg-third);
    color: var(--text-color);
    margin: 0;
    padding: 20px;
}

.container {
    max-width: 500px;
    margin: auto;
    background: var(--bg-main);
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.08);
}

h1 {
    color: var(--primary-color);
    font-size: 1.8rem;
    text-align: center;
}

.description {
    text-align: center;
    color: #555;
    margin-bottom: 20px;
}

.tool-card {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

label {
    font-weight: bold;
}

.scale-input {
    display: flex;
    align-items: center;
    gap: 8px;
}

.scale-input span {
    font-weight: bold;
}

input, select {
    padding: 8px;
    border: 1px solid #ccc;
    border-radius: 6px;
    flex: 1;
}

button {
    background: var(--primary-color);
    color: white;
    border: none;
    padding: 10px;
    font-size: 1rem;
    border-radius: 6px;
    cursor: pointer;
    transition: background 0.3s;
}

button:hover {
    background: var(--accent-color);
}

.result {
    font-size: 1.2rem;
    font-weight: bold;
    color: var(--primary-color);
    text-align: center;
}

.formula {
    font-size: 0.9rem;
    text-align: center;
    color: #777;
    margin-top: -10px;
}