/* EULER.blue Stylesheet
   Lake Eutrophication Modelling Resource
   Longline Environment Ltd, 2026
*/

:root {
    --euler-dark: #2C4253;
    --euler-medium: #576876;
    --euler-light: #87A4B8;
    --euler-accent: #4A90A4;
    --euler-highlight: #B8D4E8;
    --text-primary: #333333;
    --text-light: #666666;
    --background: #FFFFFF;
    --background-alt: #F5F8FA;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--background);
}

/* Header */
header {
    background-color: var(--euler-dark);
    color: white;
    padding: 1rem 0;
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
}

.header-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.8rem;
    font-weight: bold;
    letter-spacing: 2px;
}

.logo span {
    color: var(--euler-highlight);
}

nav ul {
    list-style: none;
    display: flex;
    gap: 2rem;
}

nav a {
    color: white;
    text-decoration: none;
    font-size: 0.95rem;
    transition: color 0.3s;
}

nav a:hover {
    color: var(--euler-highlight);
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--euler-dark) 0%, var(--euler-medium) 100%);
    color: #B8D4E8;
    padding: 8rem 2rem 4rem;
    text-align: center;
    margin-top: 60px;
}

.hero h1 {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
    letter-spacing: 1px;
    color: white;
}

.hero .subtitle {
    font-size: 1.2rem;
    color: #7FBCD2;
    margin-bottom: 1.5rem;
}

.hero p {
    max-width: 700px;
    margin: 0 auto 2rem;
    font-size: 1.1rem;
    line-height: 1.8;
    color: #B8D4E8;
}

/* Main Content */
main {
    max-width: 1200px;
    margin: 0 auto;
    padding: 3rem 2rem;
}

section {
    margin-bottom: 4rem;
}

h2 {
    color: var(--euler-dark);
    font-size: 1.8rem;
    margin-bottom: 1.5rem;
    padding-bottom: 0.5rem;
    border-bottom: 3px solid var(--euler-accent);
}

h3 {
    color: var(--euler-medium);
    font-size: 1.3rem;
    margin-bottom: 1rem;
}

p {
    margin-bottom: 1rem;
    color: var(--text-primary);
}

/* Model Cards */
.model-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.model-card {
    background: var(--background-alt);
    border-radius: 8px;
    padding: 1.5rem;
    border-left: 4px solid var(--euler-accent);
    transition: transform 0.3s, box-shadow 0.3s;
}

.model-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(44, 66, 83, 0.15);
}

.model-card h3 {
    color: var(--euler-dark);
    margin-bottom: 0.75rem;
}

.model-card p {
    color: var(--text-light);
    font-size: 0.95rem;
}

.model-card .model-type {
    display: inline-block;
    background: var(--euler-dark);
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: 4px;
    font-size: 0.8rem;
    margin-bottom: 1rem;
}

/* Info Box */
.info-box {
    background: var(--background-alt);
    border-radius: 8px;
    padding: 2rem;
    margin: 2rem 0;
}

.info-box h3 {
    color: var(--euler-dark);
}

/* Footer */
footer {
    background-color: var(--euler-dark);
    color: white;
    padding: 3rem 2rem 1.5rem;
}

.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.footer-section h4 {
    color: var(--euler-highlight);
    margin-bottom: 1rem;
    font-size: 1.1rem;
}

.footer-section p,
.footer-section a {
    color: var(--euler-light);
    font-size: 0.9rem;
}

.footer-section a {
    text-decoration: none;
    display: block;
    margin-bottom: 0.5rem;
    transition: color 0.3s;
}

.footer-section a:hover {
    color: white;
}

.footer-bottom {
    max-width: 1200px;
    margin: 2rem auto 0;
    padding-top: 1.5rem;
    border-top: 1px solid var(--euler-medium);
    text-align: center;
    color: var(--euler-light);
    font-size: 0.85rem;
}

/* Responsive */
@media (max-width: 768px) {
    .header-container {
        flex-direction: column;
        gap: 1rem;
    }
    
    nav ul {
        gap: 1rem;
    }
    
    .hero {
        padding: 6rem 1rem 3rem;
    }
    
    .hero h1 {
        font-size: 1.8rem;
    }
    
    main {
        padding: 2rem 1rem;
    }
}