* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
body {
    font-family:
        -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu,
        Cantarell, sans-serif;
    line-height: 1.6;
    color: #e5e5e5;
    background-color: #0a0a0a;
}
.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 20px;
}
header {
    background-image: url("https://assets.khoa.email/assets/bg.jpeg");
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    padding: 60px 0;
    border-bottom: 1px solid #333;
    position: relative;
}
header::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.69);
    z-index: 1;
}
.hero {
    text-align: center;
    position: relative;
    z-index: 2;
}
.hero h1 {
    font-size: 3rem;
    font-weight: 300;
    margin-bottom: 10px;
    color: #ffffff;
    letter-spacing: -1px;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.7);
}
.hero .subtitle {
    font-size: 1.2rem;
    color: #fff;
    font-weight: 300;
    margin-bottom: 30px;
    text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.7);
}
.hero .contact {
    display: flex;
    justify-content: center;
    gap: 30px;
    flex-wrap: wrap;
}
.contact a {
    color: #fff;
    text-decoration: none;
    font-size: 0.9rem;
    transition: color 0.3s ease;
    text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.7);
}
.contact a:hover {
    color: #ffffff;
}
nav {
    background: #111111;
    padding: 20px 0;
    position: sticky;
    top: 0;
    z-index: 100;
    border-bottom: 1px solid #333;
}
nav ul {
    display: flex;
    justify-content: center;
    list-style: none;
    gap: 40px;
}
nav a {
    color: #999;
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 400;
    transition: color 0.3s ease;
}
nav a:hover {
    color: #ffffff;
}
section {
    padding: 80px 0;
}
.section-title {
    font-size: 2rem;
    font-weight: 300;
    text-align: center;
    margin-bottom: 60px;
    color: #ffffff;
}
.about-content {
    max-width: 600px;
    margin: 0 auto;
    text-align: center;
    font-size: 1.1rem;
    color: #ccc;
    line-height: 1.8;
}
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 40px;
    margin-top: 40px;
}
.project-card {
    display: flex;
    flex-direction: column;
    background: #111111;
    border-radius: 8px;
    overflow: hidden;
    border: 1px solid #333;
    transition:
        transform 0.3s ease,
        box-shadow 0.3s ease;
}
.project-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(255, 255, 255, 0.05);
}
.project-image {
    width: 100%;
    height: 200px;
    background: #1a1a1a;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #666;
    font-size: 0.9rem;
}
.project-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}
.project-content {
    padding: 30px;
    display: flex;
    flex-direction: column;
    flex-grow: 1;
}
.project-content h3 {
    font-size: 1.3rem;
    font-weight: 400;
    margin-bottom: 10px;
    color: #ffffff;
}
.project-content p {
    color: #999;
    margin-bottom: 20px;
    line-height: 1.6;
    flex-grow: 1;
}
.project-links {
    margin-top: auto;
    display: flex;
    gap: 15px;
}
.project-links a {
    color: #999;
    text-decoration: none;
    font-size: 0.9rem;
    border-bottom: 1px solid transparent;
    transition:
        border-color 0.3s ease,
        color 0.3s ease;
}
.project-links a:hover {
    border-bottom-color: #999;
    color: #ffffff;
}
/* Tech stack container */
.project-tech {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: auto; /* push tech+links to bottom */
    align-items: center;
    margin-bottom: 15px; /* spacing from links */
}

.project-tech .tech {
    display: flex;
    align-items: center;
    font-size: 0.85rem;
    color: #ccc;
}

.project-tech .tech::before {
    content: "";
    display: inline-block;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background-color: var(--color, #999); /* default gray */
    margin-right: 6px;
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    max-width: 800px;
    margin: 0 auto;
}
.skill-category h3 {
    font-size: 1.2rem;
    font-weight: 400;
    margin-bottom: 20px;
    color: #ffffff;
    text-align: center;
}
.skill-category ul {
    list-style: none;
    text-align: center;
}
.skill-category li {
    color: #999;
    margin-bottom: 8px;
    font-size: 0.95rem;
}
footer {
    background: #111111;
    border-top: 1px solid #333;
    padding: 40px 0;
    text-align: center;
}
footer p {
    color: #666;
    font-size: 0.9rem;
}
@media (max-width: 768px) {
    .hero h1 {
        font-size: 2.2rem;
    }
    .hero .subtitle {
        font-size: 1rem;
    }
    nav ul {
        gap: 20px;
    }
    section {
        padding: 60px 0;
    }
    .projects-grid {
        grid-template-columns: 1fr;
    }
}

.experience-item {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}
.experience-image {
    width: 100%;
    height: 200px;
    background: #1a1a1a;
    border-radius: 8px;
    margin: 0 auto 30px auto;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #666;
    font-size: 0.9rem;
}
.experience-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: 8px;
}
.experience-details {
    text-align: left;
}
.experience-header {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 15px;
    margin-bottom: 15px;
}
.experience-header h3 {
    font-size: 1.3rem;
    font-weight: 400;
    color: #ffffff;
    margin: 0;
}
.company {
    color: #999;
    font-size: 1rem;
}
.duration {
    color: #666;
    font-size: 0.9rem;
    margin-left: auto;
}
.experience-content p {
    color: #ccc;
    line-height: 1.6;
    margin: 0;
}

@media (max-width: 768px) {
    .experience-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 5px;
    }
    .duration {
        margin-left: 0;
    }
}

.experience-content ul {
    list-style: none;
    padding: 0;
    margin: 0;
}
.experience-content li {
    color: #ccc;
    line-height: 1.7;
    margin-bottom: 12px;
    padding-left: 24px;
    position: relative;
}
.experience-content li:before {
    content: "";
    width: 6px;
    height: 6px;
    background-color: #666;
    border-radius: 50%;
    position: absolute;
    left: 8px;
    top: 12px;
}
.experience-content li:last-child {
    margin-bottom: 0;
}