* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, Arial, sans-serif;
    background: linear-gradient(135deg, #1e3c72, #2a5298);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    color: white;
}

.container {
    background: rgba(0,0,0,0.35);
    padding: 25px;
    border-radius: 15px;
    width: 100%;
    max-width: 400px;
    backdrop-filter: blur(10px);
    box-shadow: 0 10px 30px rgba(0,0,0,0.4);
}

h1 {
    text-align: center;
    margin-bottom: 20px;
}

.form-group {
    margin-bottom: 15px;
}

label {
    display: block;
    margin-bottom: 5px;
    font-size: 14px;
}

input[type="date"] {
    width: 100%;
    padding: 12px;
    border-radius: 8px;
    border: none;
    font-size: 16px;
}

.result {
    margin-top: 20px;
    font-size: 18px;
    text-align: center;
    padding: 15px;
    border-radius: 10px;
    background: rgba(255,255,255,0.1);
}

/* 📱 Mobile */
@media (max-width: 480px) {
    .container {
        margin: 15px;
        padding: 20px;
    }

    h1 {
        font-size: 20px;
    }

    .result {
        font-size: 16px;
    }
}