* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html, body {
    height: 100%;
    overflow-x: hidden;
}

body {
    background: #ebc3db;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

main {
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

nav {
    background-color: #fff;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 60px;
    padding: 10px 20px;
    border-bottom: 1px solid #333;
}

.brand img {
    width: 60px;
    height: auto;
}

.nav-links {
    display: flex;
    gap: 40px;
}

.nav-links a {
    color: black;
    text-decoration: none;
    font-weight: bold;
    font-size: 20px;
    padding: 8px 15px;
    transition: 0.2s ease;
    white-space: nowrap;
}

.nav-links a:hover {
    background-color: #ffeddf;
    border-radius: 10px;
    transform: translateY(-2px);
}

.nav-links a:active {
    transform: scale(0.96);
}

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

.head h1 {
    font-size: 40px;
    margin-bottom: 10px;
}

.head p {
    font-size: 18px;
}

.calculator {
    width: 100%;
    max-width: 360px;
    padding: 40px;
    background-color: #ffeddf;
    border-radius: 20px;
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
    text-align: center;
}

.calculator label {
    display: block;
    font-size: 18px;
    font-weight: bold;
    margin-bottom: 20px;
}

.calculator input[type="date"] {
    width: 100%;
    padding: 8px;
    font-size: 16px;
    border-radius: 8px;
    border: 1px solid #333;
    margin-bottom: 20px;
}

.btn {
    display: flex;
    gap: 15px;
    justify-content: center;
    margin-bottom: 20px;
}

.calculator button {
    padding: 10px 20px;
    font-size: 15px;
    border-radius: 8px;
    border: none;
    font-weight: bold;
    cursor: pointer;
    transition: 0.2s ease;
}

.calculator button[type="submit"] {
    background-color: #e07a9c;
    color: white;
}

.calculator button[type="reset"] {
    background-color: #888;
    color: white;
}

.calculator button:hover {
    transform: translateY(-2px);
}

.calculator button:active {
    transform: scale(0.96);
}

footer {
    background-color: #fff;
    border-top: 1px solid #333;
    padding: 15px 0;
}

.footer-bottom {
    text-align: center;
    font-size: 14px;
    font-weight: bold;
}

.footer-bottom .developer strong {
    color: #c0392b;
}

.github-link {
    text-decoration: none;
    color: inherit;
    font-weight: inherit;
}

.github-link i {
    margin-right: 6px;
}

.github-link:hover {
    color: blue;
}

@media (max-width: 768px) {
    nav {
        padding: 8px 12px;
    }

    .brand img {
        width: 55px;
    }

    .nav-links {
        gap: 15px;
    }

    .nav-links a {
        font-size: 14px;
        padding: 6px 8px;
    }

    .head h1 {
        font-size: 26px;
    }

    .head p {
        font-size: 16px;
    }

    .calculator {
        max-width: 290px;
    }

    .btn {
        flex-direction: column;
        margin-bottom: 30px;
    }

    .calculator button {
        width: 100%;
    }
}