:root {
    /* Chiang Mai University Colors */
    --cmu-purple: #9E76B4;
    --cmu-green: #286428;
    
    --bg-color: #ffffff;
    --bg-light: #f8f9fa;
    --text-color: #333333;
    --text-muted: #666666;
    --border-color: #e9ecef;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    color: var(--text-color);
    line-height: 1.6;
    background-color: var(--bg-color);
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* Header & Navigation */
header {
    background-color: rgba(255, 255, 255, 0.95);
    border-bottom: 1px solid var(--border-color);
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    backdrop-filter: blur(5px);
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.5rem 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.logo {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--cmu-purple);
}

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

.nav-links a {
    text-decoration: none;
    color: var(--text-muted);
    font-weight: 400;
    transition: color 0.3s ease;
}

.nav-links a:hover {
    color: var(--cmu-purple);
}

/* Sections */
.section {
    padding: 6rem 0;
    min-height: auto;
}

.bg-light {
    background-color: var(--bg-light);
}

h1 {
    font-size: 3rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text-color);
}

h2 {
    font-size: 2rem;
    font-weight: 600;
    margin-bottom: 2rem;
    color: var(--cmu-purple);
    border-bottom: 2px solid var(--cmu-green);
    display: inline-block;
    padding-bottom: 0.5rem;
}

h3 {
    font-size: 1.25rem;
    margin-bottom: 1rem;
    color: var(--text-color);
}

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

.subtitle {
    font-size: 1.25rem;
    color: var(--cmu-purple);
    margin-bottom: 2rem;
}

/* Home Content */
.home-content {
    display: flex;
    align-items: center;
    gap: 3rem;
    margin-top: 2rem;
}

.profile-photo {
    width: 200px;
    height: 200px;
    border-radius: 50%;
    object-fit: cover;
    border: 4px solid var(--cmu-purple);
    box-shadow: 0 10px 20px rgba(0,0,0,0.1);
    flex-shrink: 0;
}

@media (max-width: 768px) {
    .home-content {
        flex-direction: column;
        text-align: center;
    }
}

/* Components */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    background-color: var(--cmu-purple);
    color: white;
    text-decoration: none;
    border-radius: 4px;
    transition: background-color 0.3s ease;
    margin-top: 1rem;
    font-weight: 600;
}

.btn:hover {
    background-color: var(--cmu-green);
}

.btn-outline {
    display: inline-block;
    padding: 0.5rem 1rem;
    border: 1px solid var(--cmu-purple);
    color: var(--cmu-purple);
    text-decoration: none;
    border-radius: 4px;
    transition: all 0.3s ease;
    margin-top: 1rem;
    font-weight: 600;
}

.btn-outline:hover {
    background-color: var(--cmu-purple);
    color: white;
}

/* Grids & Cards */
.content-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.card {
    background: var(--bg-color);
    padding: 2rem;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.bg-light .card {
    background: var(--bg-color);
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0,0,0,0.05);
}

/* Publication List */
.publication-list {
    list-style: none;
}

.publication-list li {
    padding: 1.5rem 0;
    border-bottom: 1px solid var(--border-color);
}

.publication-list li:last-child {
    border-bottom: none;
}

.link {
    color: var(--cmu-purple);
    text-decoration: none;
    margin-left: 0.5rem;
    font-size: 0.9rem;
    font-weight: 600;
}

.link:hover {
    text-decoration: underline;
    color: var(--cmu-green);
}

/* Footer */
footer {
    text-align: center;
    padding: 3rem 0;
    background-color: #f1f3f5;
    color: var(--text-muted);
    border-top: 1px solid var(--border-color);
}

footer p {
    color: var(--text-muted);
    margin: 0;
}

/* Responsive */
@media (max-width: 768px) {
    nav {
        flex-direction: column;
        gap: 1rem;
        padding: 1rem;
    }
    .nav-links {
        gap: 1rem;
        flex-wrap: wrap;
        justify-content: center;
    }
    
    h1 {
        font-size: 2rem;
    }
    
    .section {
        padding: 4rem 0;
    }
}