/* AERIS Lab - NC State University */

:root {
    --red: #CC0000;
    --red-dark: #990000;
    --black: #222222;
    --gray: #666666;
    --light-gray: #F5F5F5;
    --border: #E0E0E0;
    --white: #FFFFFF;
    --max-width: 1100px;
    --font: -apple-system, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
}

/* Reset & Base */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

body {
    font-family: var(--font);
    color: var(--black);
    line-height: 1.6;
    background: var(--white);
}

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 1.5rem;
}

a { color: var(--red); text-decoration: none; }
a:hover { color: var(--red-dark); text-decoration: underline; }

img { max-width: 100%; height: auto; }

h1, h2, h3, h4 { line-height: 1.3; margin-bottom: 0.5rem; }
h1 { font-size: 2rem; }
h2 { font-size: 1.5rem; color: var(--red); }
h3 { font-size: 1.2rem; }

p { margin-bottom: 1rem; }

/* Header */
.site-header {
    background: var(--white);
    border-bottom: 3px solid var(--red);
    position: sticky;
    top: 0;
    z-index: 100;
}

.site-header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 70px;
}

.logo img { height: 50px; width: auto; }

.nav-toggle { display: none; background: none; border: none; font-size: 1.5rem; cursor: pointer; }

.main-nav {
    display: flex;
    gap: 0.25rem;
    align-items: center;
}

.nav-item { position: relative; }

.nav-item > a {
    display: block;
    padding: 0.5rem 0.75rem;
    color: var(--black);
    font-size: 0.95rem;
    font-weight: 500;
    border-radius: 4px;
    transition: background 0.15s;
}

.nav-item > a:hover,
.nav-item > a.active {
    background: var(--red);
    color: var(--white);
    text-decoration: none;
}

/* Dropdown */
.dropdown {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    background: var(--white);
    border: 1px solid var(--border);
    border-radius: 4px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
    min-width: 160px;
    z-index: 200;
}

.has-dropdown:hover .dropdown { display: block; }

.dropdown a {
    display: block;
    padding: 0.5rem 1rem;
    color: var(--black);
    font-size: 0.9rem;
}

.dropdown a:hover {
    background: var(--light-gray);
    color: var(--red);
    text-decoration: none;
}

/* Hero */
.hero {
    background: var(--red);
    color: var(--white);
    padding: 3rem 0;
    text-align: center;
}

.hero h1 { font-size: 2.5rem; color: var(--white); margin-bottom: 0.5rem; }
.hero p { font-size: 1.15rem; opacity: 0.9; max-width: 700px; margin: 0 auto; }

/* Page Header */
.page-header {
    background: var(--light-gray);
    padding: 2rem 0;
    border-bottom: 1px solid var(--border);
    margin-bottom: 2rem;
}

.page-header h1 { margin-bottom: 0.25rem; }
.page-header p { color: var(--gray); margin-bottom: 0; }

/* Content */
.content { padding: 2rem 0; }
.content-body { }
.content-body h2 { margin-top: 1.5rem; }
.content-body ul, .content-body ol { margin-left: 1.5rem; margin-bottom: 1rem; }
.content-body li { margin-bottom: 0.25rem; }

/* Cards */
.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
    margin-top: 1.5rem;
}

.card {
    border: 1px solid var(--border);
    border-radius: 6px;
    overflow: hidden;
    transition: box-shadow 0.2s;
}

.card:hover { box-shadow: 0 4px 16px rgba(0,0,0,0.1); }

.card-image {
    width: 100%;
    height: 180px;
    object-fit: cover;
    background: var(--light-gray);
}

.card-body { padding: 1.25rem; }
.card-body h3 { margin-bottom: 0.5rem; }
.card-body h3 a { color: var(--black); }
.card-body h3 a:hover { color: var(--red); }
.card-body p { font-size: 0.9rem; color: var(--gray); margin-bottom: 0.5rem; }

.card-tag {
    display: inline-block;
    background: var(--light-gray);
    color: var(--gray);
    padding: 0.15rem 0.5rem;
    border-radius: 3px;
    font-size: 0.8rem;
    margin-right: 0.25rem;
}

/* People */
.people-section { margin-bottom: 2.5rem; }
.people-section h2 { margin-bottom: 1rem; border-bottom: 2px solid var(--red); padding-bottom: 0.5rem; }

.people-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 1.5rem;
}

.person-card { text-align: center; }

.person-photo {
    width: 150px;
    height: 150px;
    border-radius: 50%;
    object-fit: cover;
    margin-bottom: 0.75rem;
    border: 3px solid var(--border);
    background: var(--light-gray);
}

.person-card h3 { font-size: 1.05rem; margin-bottom: 0.15rem; }
.person-card .person-role { color: var(--gray); font-size: 0.9rem; }
.person-card .person-research { font-size: 0.85rem; color: var(--gray); margin-top: 0.25rem; }

/* Project Detail */
.project-meta {
    display: flex;
    gap: 1.5rem;
    flex-wrap: wrap;
    margin-bottom: 1.5rem;
    padding: 1rem;
    background: var(--light-gray);
    border-radius: 6px;
    font-size: 0.9rem;
}

.project-meta dt { font-weight: 600; }
.project-meta dd { color: var(--gray); }

/* News */
.news-list { list-style: none; }

.news-item {
    padding: 1rem 0;
    border-bottom: 1px solid var(--border);
}

.news-item:last-child { border-bottom: none; }
.news-date { font-size: 0.85rem; color: var(--gray); }
.news-title { font-weight: 600; }

/* Contact */
.contact-info dt { font-weight: 600; margin-top: 0.75rem; }
.contact-info dd { color: var(--gray); }

/* Two column layout */
.two-col {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 3rem;
    align-items: start;
}

/* Footer */
.site-footer {
    background: var(--red);
    color: var(--white);
    padding: 2rem 0;
    margin-top: 3rem;
    text-align: center;
}

.site-footer a { color: var(--white); text-decoration: underline; }
.footer-name { font-weight: 600; font-size: 1.05rem; }
.footer-copy { margin-top: 0.75rem; font-size: 0.85rem; opacity: 0.8; }

/* Responsive */
@media (max-width: 768px) {
    .nav-toggle { display: block; }

    .main-nav {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 70px;
        left: 0;
        right: 0;
        background: var(--white);
        border-bottom: 3px solid var(--red);
        padding: 1rem;
    }

    .main-nav.open { display: flex; }

    .dropdown {
        position: static;
        box-shadow: none;
        border: none;
        padding-left: 1rem;
    }

    .has-dropdown:hover .dropdown { display: block; }

    .two-col { grid-template-columns: 1fr; }
    .hero h1 { font-size: 1.8rem; }
    .card-grid { grid-template-columns: 1fr; }
}