/* Basic Reset & Defaults */
:root {
    --primary-color: #007bff; /* Example blue */
    --secondary-color: #6c757d; /* Example gray */
    --background-color: #f8f9fa;
    --text-color: #333;
    --card-bg: #fff;
    --border-radius: 5px;
}

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

body {
    font-family: sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--background-color);
}

.container {
    max-width: 960px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
header {
    background-color: var(--card-bg);
    padding: 1rem 0;
    border-bottom: 1px solid #eee;
    margin-bottom: 2rem;
}

header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

header .logo {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
    text-decoration: none;
}

header nav button {
    background: none;
    border: 1px solid var(--secondary-color);
    color: var(--secondary-color);
    padding: 0.3rem 0.7rem;
    margin-left: 0.5rem;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-size: 0.9rem;
    transition: background-color 0.2s, color 0.2s;
}
header nav button:hover,
header nav button.active { /* We'll add 'active' class via JS */
    background-color: var(--secondary-color);
    color: white;
}


/* Main Content Sections */
main section {
    padding: 3rem 0;
}

main section#hero {
    text-align: center;
    background-color: var(--card-bg); /* Light background for hero */
    padding: 4rem 0;
}

h1 {
    font-size: 2.8rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

h2 {
    font-size: 2rem;
    margin-bottom: 1.5rem;
    text-align: center;
    color: #555;
}

h3 {
    font-size: 1.4rem;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

p {
    margin-bottom: 1rem;
    color: #555;
}

/* Buttons */
.button {
    display: inline-block;
    background-color: var(--primary-color);
    color: white;
    padding: 0.8rem 1.5rem;
    text-decoration: none;
    border-radius: var(--border-radius);
    transition: background-color 0.2s;
    margin: 0.5rem;
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

.button:hover {
    background-color: #0056b3; /* Darker blue on hover */
}

.button-secondary {
    background-color: var(--secondary-color);
}

.button-secondary:hover {
    background-color: #5a6268; /* Darker gray on hover */
}

.cta-buttons {
    margin-top: 1.5rem;
}


/* Projects Section */
.project-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); /* Responsive grid */
    gap: 1.5rem;
    margin-top: 2rem;
}

.project-item {
    background-color: var(--card-bg);
    padding: 1.5rem;
    border-radius: var(--border-radius);
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

.project-item a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: bold;
}
.project-item a:hover {
    text-decoration: underline;
}


/* Join Section */
#join {
    text-align: center;
    background-color: var(--card-bg);
}

/* Footer */
footer {
    background-color: #e9ecef;
    color: #6c757d;
    text-align: center;
    padding: 1.5rem 0;
    margin-top: 3rem;
    font-size: 0.9rem;
}

/* Basic Responsiveness */
@media (max-width: 768px) {
    h1 { font-size: 2.2rem; }
    h2 { font-size: 1.8rem; }
    header .container { flex-direction: column; gap: 0.5rem;}
}