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

body {
    font-family: 'Roboto', sans-serif;
    background-color: #e8f5e9;
    color: #1b5e20;
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
}

.top-nav {
    background-color: #2e7d32;
    padding: 12px 0;
    text-align: center;
}

.top-nav a {
    color: #c8e6c9;
    text-decoration: none;
    margin: 0 15px;
    font-size: 16px;
    transition: color 0.3s;
}

.top-nav a:hover {
    color: #a5d6a7;
}

.main-content {
    padding: 20px 0;
    text-align: center;
}

h1 {
    font-size: 28px;
    color: #f57c00;
    margin-bottom: 20px;
}

.banner-container {
    margin-bottom: 20px;
}

.banner-img {
    width: auto;
    max-height: 350px;
    object-fit: cover;
    border-radius: 8px;
    border: 1px solid #81c784;
}

.calculator-section {
    background: linear-gradient(135deg, #ffffff, #f1f8e9);
    border: 2px solid #f57c00;
    border-radius: 10px;
    padding: 20px;
    margin-bottom: 20px;
    box-shadow: 0 6px 15px rgba(0,0,0,0.1);
}

.input-group {
    margin-bottom: 15px;
    text-align: left;
    display: flex;
    align-items: center;
    gap: 10px;
}

.input-group label {
    font-size: 16px;
    flex: 0 0 150px;
    color: #1b5e20;
}

.input-group .input-wrapper {
    flex: 1;
    display: flex;
    gap: 10px;
}

.input-group input,
.input-group select {
    padding: 10px;
    font-size: 16px;
    border: 1px solid #81c784;
    border-radius: 5px;
    background-color: #f1f8e9;
    transition: border-color 0.3s, box-shadow 0.3s;
}

.input-group input:focus,
.input-group select:focus {
    outline: none;
    border-color: #f57c00;
    box-shadow: 0 0 5px rgba(245, 124, 0, 0.3);
}

.gender-selection,
.standard-selection {
    display: flex;
    gap: 20px;
}

.gender-selection label,
.standard-selection label {
    display: inline-flex;
    align-items: center;
    margin-right: 15px;
    font-size: 16px;
}

.gender-selection input,
.standard-selection input {
    margin-right: 5px;
    width: 18px;
    height: 18px;
}

.gender-label i {
    margin-left: 5px;
    font-size: 20px;
}

.gender-label .fa-male {
    color: #1e90ff;
}

.gender-label .fa-female {
    color: #ff69b4;
}

.calculate-btn,
.reset-btn {
    background-color: #2e7d32;
    color: #ffffff;
    border: none;
    padding: 10px 20px;
    font-size: 16px;
    border-radius: 25px;
    cursor: pointer;
    margin: 10px 5px;
    box-shadow: 0 3px 6px rgba(0,0,0,0.2);
    transition: background-color 0.3s, transform 0.2s;
}

.calculate-btn:hover,
.reset-btn:hover {
    background-color: #ef6c00;
    transform: translateY(-2px);
}

.results {
    margin-top: 20px;
    padding: 15px;
    background-color: #f1f8e9;
    border-left: 5px solid #388e3c;
    border-radius: 5px;
    text-align: left;
}

.results h2 {
    color: #388e3c;
    margin-bottom: 10px;
}

.results p {
    font-size: 16px;
    margin-bottom: 8px;
}

.hint {
    font-size: 14px;
    color: #78909c;
    margin-top: 10px;
}

.info-section {
    text-align: justify;
    margin-bottom: 20px;
}

.info-section h2 {
    font-size: 22px;
    color: #ef6c00;
    margin-bottom: 10px;
}

.info-section p,
.info-section ul {
    font-size: 16px;
    line-height: 1.6;
    color: #1b5e20;
}

.info-section ul {
    list-style-type: disc;
    padding-left: 20px;
}

.note {
    font-style: italic;
    color: #78909c;
}

.copyright {
    text-align: center;
    font-size: 14px;
    color: #78909c;
    padding: 20px 0;
    border-top: 1px solid #81c784;
}

.copyright a {
    color: #2e7d32;
    text-decoration: none;
}

.copyright a:hover {
    color: #1b5e20;
}

@media (max-width: 768px) {
    h1 {
        font-size: 24px;
    }

    .top-nav a {
        font-size: 14px;
        margin: 0 10px;
    }

    .calculator-section {
        padding: 15px;
    }

    .input-group {
        flex-direction: column;
        align-items: flex-start;
    }

    .input-group label {
        flex: none;
        margin-bottom: 5px;
    }

    .input-group .input-wrapper {
        width: 100%;
        flex-direction: column;
        gap: 5px;
    }

    .input-group input,
    .input-group select {
        width: 100%;
        font-size: 14px;
    }

    .gender-selection,
    .standard-selection {
        flex-direction: column;
        gap: 10px;
    }

    .calculate-btn,
    .reset-btn {
        font-size: 14px;
        padding: 8px 15px;
    }
}