body {
    margin: 0;
    padding: 0;
    background: #0b0e15;
    color: white;
    font-family: 'Pretendard', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

*,
*::before,
*::after {
    box-sizing: border-box;
}

.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    padding: 20px 60px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    z-index: 9999;
    background: rgba(11, 14, 21, 0.9);
    backdrop-filter: blur(10px);
}

.logo {
    font-weight: 700;
    font-size: 20px;
}

.nav a {
    margin-left: 20px;
    color: #fff;
    text-decoration: none;
    transition: color 0.3s;
}

.nav a:hover {
    color: #3b82f6;
}

.btn-primary {
    padding: 10px 20px;
    border-radius: 20px;
    background: #2563eb;
    color: #fff;
    cursor: pointer;
    border: none;
    transition: all 0.3s;
}

.btn-primary:hover {
    background: #1d4ed8;
    transform: translateY(-2px);
}

.hero {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 150px 60px;
    min-height: 100vh;
}

.hero-text h1 {
    font-size: 45px;
    line-height: 1.3;
    margin-bottom: 20px;
}

.hero-text span {
    color: #3b82f6;
}

.hero-img {
    flex-shrink: 0;
}

.hero-img img {
    width: 280px;
    height: 280px;
    border-radius: 20px;
    object-fit: cover;
    box-shadow: 0 10px 40px rgba(59, 130, 246, 0.3);
}

.about {
    padding: 100px 60px;
}

.about h2 {
    margin-bottom: 30px;
    font-size: 32px;
}

.about ul {
    list-style: none;
    padding: 0;
}

.about ul li {
    padding: 15px 0;
    padding-left: 30px;
    position: relative;
    font-size: 18px;
    line-height: 1.6;
}

.about ul li::before {
    content: "✓";
    position: absolute;
    left: 0;
    color: #3b82f6;
    font-weight: bold;
}

.projects {
    padding: 100px 60px;
}

.projects h2 {
    margin-bottom: 40px;
    font-size: 32px;
}

.project-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.project-card {
    background: #111827;
    padding: 20px;
    border-radius: 16px;
    cursor: pointer;
    transition: all 0.3s;
    border: 1px solid transparent;
}

.project-card:hover {
    transform: translateY(-8px);
    border-color: #3b82f6;
    box-shadow: 0 10px 30px rgba(59, 130, 246, 0.3);
}

.project-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    border-radius: 12px;
    margin-bottom: 15px;
    background: #1f2937;
}

/* 이미지 로딩 실패 시 대체 텍스트 */
.project-card img[alt]::after {
    content: attr(alt);
    display: block;
    text-align: center;
    padding: 80px 20px;
    background: #1f2937;
    border-radius: 12px;
}

.project-card h3 {
    font-size: 18px;
    margin-bottom: 10px;
    color: #fff;
}

.project-card p {
    color: #9ca3af;
    font-size: 14px;
}

/* 반응형 */
@media (max-width: 1024px) {
    .project-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .header {
        padding: 20px 30px;
    }

    .hero {
        flex-direction: column;
        padding: 120px 30px 60px;
        text-align: center;
    }

    .hero-text h1 {
        font-size: 36px;
    }

    .hero-img {
        margin-top: 40px;
    }

    .about,
    .projects {
        padding: 60px 30px;
    }

    .project-grid {
        grid-template-columns: 1fr;
    }

    .nav {
        display: none;
    }
}