* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    background-color: #f4f7f6;
    color: #333;
    padding-bottom: 40px;
}

header {
    background-color: #2c3e50;
    color: white;
    text-align: center;
    padding: 30px 20px;
}

header h1 {
    margin-bottom: 8px;
}

.contenedor {
    max-width: 800px;
    margin: 30px auto;
    padding: 0 20px;
}

.caja-calculadora {
    background: white;
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    margin-bottom: 30px;
}

.caja-calculadora h2 {
    margin-bottom: 20px;
    color: #2c3e50;
}

.grupo-input {
    margin-bottom: 20px;
}

.grupo-input label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
}

.grupo-input input, .grupo-input select {
    width: 100%;
    padding: 12px;
    border: 1px solid #ccc;
    border-radius: 4px;
    font-size: 16px;
}

.botones {
    display: flex;
    gap: 15px;
    margin-bottom: 25px;
}

button {
    flex: 1;
    padding: 12px;
    background-color: #27ae60;
    color: white;
    border: none;
    border-radius: 4px;
    font-size: 16px;
    font-weight: bold;
    cursor: pointer;
    transition: background 0.2s;
}

button:hover {
    background-color: #219653;
}

button:nth-child(2) {
    background-color: #2980b9;
}

button:nth-child(2):hover {
    background-color: #2471a3;
}

.resultado {
    background-color: #e8f4f8;
    padding: 20px;
    border-radius: 6px;
    border-left: 5px solid #2980b9;
}

.resultado p {
    margin-bottom: 10px;
    font-size: 18px;
}

.resultado .total {
    font-size: 22px;
    color: #2c3e50;
    border-top: 1px solid #d0d7de;
    padding-top: 10px;
    margin-bottom: 0;
}

.hidden {
    display: none;
}

.contenido-texto {
    line-height: 1.6;
}

.contenido-texto h2, .contenido-texto h3 {
    margin: 20px 0 10px 0;
    color: #2c3e50;
}

.contenido-texto p {
    margin-bottom: 15px;
}

code {
    background: #e1e8ed;
    padding: 2px 6px;
    border-radius: 4px;
    font-family: monospace;
}

footer {
    text-align: center;
    color: #7f8c8d;
    font-size: 14px;
    margin-top: 40px;
}