body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #1e3c72, #2a5298);
    margin: 0;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    color: #333;
}

.container {
    background: rgba(255, 255, 255, 0.95);
    border-radius: 2rem;
    padding: 2rem;
    max-width: 500px;
    width: 90%;
    text-align: center;
    box-shadow: 0 20px 35px rgba(0,0,0,0.2);
    transition: transform 0.2s;
}

h1 {
    margin-top: 0;
    color: #1e3c72;
}

.upload-area {
    margin: 1.5rem 0;
}

.file-label {
    background-color: #2a5298;
    color: white;
    padding: 0.8rem 1.5rem;
    border-radius: 2rem;
    cursor: pointer;
    display: inline-block;
    transition: background 0.3s;
}

.file-label:hover {
    background-color: #1e3c72;
}

input[type="file"] {
    display: none;
}

.preview {
    margin: 1rem 0;
    min-height: 200px;
    display: flex;
    justify-content: center;
}

#previewImg {
    max-width: 100%;
    max-height: 250px;
    border-radius: 1rem;
    box-shadow: 0 4px 12px rgba(0,0,0,0.2);
    display: none;
}

button {
    background-color: #28a745;
    color: white;
    border: none;
    padding: 0.8rem 1.8rem;
    font-size: 1rem;
    border-radius: 2rem;
    cursor: pointer;
    transition: all 0.2s;
    margin-top: 1rem;
}

button:disabled {
    background-color: #6c757d;
    cursor: not-allowed;
}

button:hover:not(:disabled) {
    background-color: #218838;
    transform: scale(1.02);
}

.result {
    margin-top: 1.5rem;
    font-size: 1.6rem;
    font-weight: bold;
    padding: 1rem;
    border-radius: 1rem;
    background: #f8f9fa;
}

.result.hombre {
    color: #28a745;
    background: #e6f4ea;
}

.result.mujer {
    color: #28a745;
    background: #fce8e6;
}

footer {
    margin-top: 2rem;
    font-size: 0.8rem;
    color: #6c757d;
}