body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background: #eaf5ff; /* light blue */
    color: #232323;
}

header.site-header {
    position: sticky;
    top: 0;
    z-index: 999;
    background: #003366;
    box-shadow: 0 2px 8px rgba(0,0,0,0.2);
}

header .header-inner {
    max-width: 1000px;
    margin: 0 auto;
    padding: 10px 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
}

header .site-title {
    color: white;
    font-weight: bold;
    letter-spacing: 0.03rem;
}

nav {
    display: flex;
    align-items: center;
    gap: 12px;
}

nav a {
    color: white;
    margin: 4px 6px;
    text-decoration: none;
    font-weight: bold;
    padding: 8px 12px;
    border-radius: 5px;
}

nav a:hover {
    background: rgba(255,255,255,0.15);
}

nav a.active {
    background: #e0f2ff;
    color: #003366;
}

.nav-toggle {
    display: none;
    background: transparent;
    border: 1px solid rgba(255,255,255,0.8);
    color: #fff;
    padding: 8px 10px;
    border-radius: 6px;
    font-size: 1rem;
    cursor: pointer;
}

.profile-image {
    width: 140px;
    height: 140px;
    object-fit: cover;
    border-radius: 50%;
    display: block;
    margin-bottom: 18px;
    border: 3px solid #ffffff;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}

img {
    max-width: 100%;
    display: block;
    border-radius: 8px;
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 20px;
}

section {
    padding: 40px 20px;
}

h1, h2, h3 {
    color: #333;
    margin-bottom: 16px;
}

p {
    line-height: 1.6;
    color: #444;
    margin-bottom: 16px;
}

button, input[type="submit"] {
    background: #007acc;
    color: white;
    border: none;
    border-radius: 6px;
    padding: 10px 20px;
    cursor: pointer;
    font-weight: bold;
}

button:hover, input[type="submit"]:hover {
    background: #005fa3;
}

form input,
form textarea {
    width: 100%;
    border: 1px solid #ccc;
    border-radius: 6px;
    padding: 10px;
    margin-bottom: 12px;
    box-sizing: border-box;
}

nav {
    background: black;
    padding: 10px;
    display: flex;
    justify-content: center;
    gap: 16px;
    flex-wrap: wrap;
}

nav a {
    color: white;
    margin: 4px 6px;
    text-decoration: none;
    font-weight: bold;
}

nav a {
    color: white;
    margin: 4px 6px;
    text-decoration: none;
    font-weight: bold;
    padding: 8px 12px;
    border-radius: 5px;
}

nav a:hover {
    background: rgba(255,255,255,0.15);
}

nav a.active {
    background: #e0f2ff;
    color: #003366;
}

@media (max-width: 768px) {
    body {
        font-size: 16px;
    }

    .container {
        padding: 14px;
    }

    .header-inner {
        width: 100%;
        justify-content: space-between;
    }

    .nav-toggle {
        display: inline-block;
    }

    nav {
        display: none;
        width: 100%;
        margin-top: 10px;
        flex-direction: column;
        gap: 8px;
    }

    nav.open {
        display: flex;
    }

    nav a {
        width: 100%;
        text-align: center;
        padding: 10px 0;
        border-radius: 6px;
        margin: 2px 0;
    }

    .projects {
        grid-template-columns: 1fr;
        gap: 16px;
    }

    .card {
        padding: 12px;
    }

    section {
        padding: 30px 12px;
    }

    .intro {
        font-size: 0.95rem;
    }

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

@media (min-width: 769px) and (max-width: 1024px) {
    .projects {
        grid-template-columns: repeat(2, 1fr);
        gap: 18px;
    }
}

.projects {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 20px;
}

.card {
    border: 1px solid #ccc;
    padding: 15px;
    border-radius: 10px;
    box-shadow: 0 3px 8px rgba(0,0,0,0.08);
    background: white;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.card:hover {
    transform: translateY(-8px);
    box-shadow: 0 8px 14px rgba(0,0,0,0.15);
}

.card img {
    width: 100%;
    height: 140px;
    object-fit: cover;
}

.card h3 {
    margin-top: 12px;
}

.project-links {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
    margin-top: 12px;
}

.button {
    display: inline-block;
    background: #005fa3;
    color: #fff;
    border: none;
    text-decoration: none;
    border-radius: 6px;
    padding: 8px 14px;
    font-size: 0.9rem;
    transition: background 0.2s ease;
}

.button:hover {
    background: #004080;
}

.button-secondary {
    background: #e0e0e0;
    color: #333;
}

.button-secondary:hover {
    background: #c8c8c8;
}

.intro {
    margin-bottom: 24px;
    color: #555;
}

.side-nav-panel {
    background: rgba(255,255,255,0.9);
    border: 1px solid #bfdcff;
    border-radius: 10px;
    padding: 16px;
    margin: 0;
}

.side-nav-panel h3 {
    margin-top: 0;
    color: #003366;
}

.side-nav-panel ul {
    list-style: none;
    margin: 8px 0 0;
    padding: 0;
}

.side-nav-panel li {
    margin-bottom: 8px;
}

.side-nav-panel a {
    color: #005fa3;
    text-decoration: none;
    font-weight: 600;
}

.side-nav-panel a:hover {
    text-decoration: underline;
}

.main-layout {
    display: grid;
    grid-template-columns: 240px 1fr;
    gap: 18px;
    align-items: start;
}

.main-content {
    background: rgba(255,255,255,0.85);
    border-radius: 10px;
    padding: 20px;
}

@media (max-width: 900px) {
    .main-layout {
        display: block;
    }

    .side-nav-panel {
        margin-bottom: 20px;
    }
}

.footer {
    text-align: center;
    padding: 20px;
    background: #f8f8f8;
    color: #666;
    border-top: 1px solid #ddd;
}