:root {
    --primary-color: #007bff;
    --secondary-color: #6c757d;
    --dark-color: #343a40;
    --text-color: #1f2937;
    --text-muted: #6b7280;
    --background-color: #ffffff;
    --border-color: #e5e7eb;
    --card-detail-bg: #f9fafb;
    --font-main: 'Pretendard', sans-serif;
}

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

html { scroll-behavior: smooth; }

body {
    font-family: var(--font-main);
    line-height: 1.7;
    color: var(--text-color);
    background: var(--background-color);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container { max-width: 1024px; margin: 0 auto; padding: 0 1.5rem; }

/* Header */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}
.header {
    text-align: left;
    padding: 8rem 0;
    animation: fadeIn 1s ease-out;
}
.header h1 {
    font-size: 3.25rem;
    font-weight: 800;
    letter-spacing: -0.02em;
    line-height: 1.3;
    margin-bottom: 1.5rem; /* 간격 조정 */
    color: var(--text-color);
}
.header-subline {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 2rem;
}
.header .role {
    font-size: 1.25rem;
    color: var(--text-muted);
    font-weight: 400;
    margin: 0;
}
.btn-cta {
    text-decoration: none;
    font-weight: 500;
    color: var(--primary-color);
    transition: all 0.2s ease;
    font-size: 1.1rem;
    padding: 0.5rem 0;
    white-space: nowrap;
}
.btn-cta:hover {
    color: var(--dark-color);
}


/* Side Navigation */
.side-nav {
    position: fixed;
    top: 50%;
    right: 2rem;
    transform: translateY(-50%);
    z-index: 1000;
}
.side-nav ul { list-style: none; }
.side-nav li { margin-bottom: 1rem; }
.side-nav a {
    text-decoration: none;
    display: flex;
    align-items: center;
    justify-content: flex-end;
    transition: all 0.3s ease;
}
.side-nav .nav-text {
    display: none;
    opacity: 0;
    background: var(--dark-color);
    color: white;
    padding: 0.3rem 0.8rem;
    border-radius: 6px;
    font-size: 0.85rem;
    font-weight: 500;
    margin-right: 0.8rem;
    white-space: nowrap;
    transition: all 0.3s ease;
}
.side-nav .nav-dot {
    width: 8px;
    height: 8px;
    background-color: #ccc;
    border-radius: 50%;
    transition: all 0.3s ease;
    border: 2px solid var(--background-color);
    box-shadow: 0 0 0 1px var(--border-color);
}
.side-nav a:hover .nav-text{
    display: block;
    opacity: 1;
}
.side-nav a:hover .nav-dot,
.side-nav a.active .nav-dot {
    transform: scale(1.5);
    background-color: var(--primary-color);
    box-shadow: 0 0 0 1px var(--primary-color);
}

/* Projects Section */
.projects-section { display: flex; flex-direction: column; gap: 4rem; margin-bottom: 6rem; }
.project-card {
    border: 1px solid var(--border-color);
    padding: 2.5rem;
    border-radius: 16px;
    display: grid;
    grid-template-columns: 1fr;
    gap: 2rem;
    transition: box-shadow 0.3s ease, border-color 0.3s ease;
}
.project-card:hover {
    box-shadow: 0 8px 25px -5px rgba(0,0,0,0.07), 0 4px 6px -4px rgba(0,0,0,0.05);
}
.project-card:target {
    /* border-color: var(--primary-color); */
    box-shadow: 0 8px 25px -5px rgba(0, 123, 255, 0.1), 0 4px 6px -4px rgba(0, 123, 255, 0.07);
}
.project-main { display: flex; flex-direction: column; }
.project-details { background-color: var(--card-detail-bg); border-radius: 12px; padding: 2rem; }
.project-header { display: flex; align-items: center; margin-bottom: 1.25rem; gap: 1rem; }
.project-title { font-size: 1.75rem; font-weight: 600; }
.project-status { background: #fef3c7; color: #92400e; padding: 0.3rem 0.9rem; border-radius: 20px; font-size: 0.8rem; font-weight: 500; margin-left: auto; }
.project-description { color: var(--text-muted); font-size: 1rem; line-height: 1.8; flex-grow: 1; }

/* Project Tabs */
.tab-buttons { display: flex; border-bottom: 1px solid var(--border-color); margin-bottom: 1.5rem; }
.tab-button {
    background: none; border: none; padding: 0.8rem 1rem; cursor: pointer;
    font-size: 1rem; font-weight: 500; color: var(--text-muted);
    border-bottom: 2px solid transparent; margin-bottom: -1px; transition: all 0.2s ease;
}
.tab-button:hover { color: var(--text-color); }
.tab-button.active { color: var(--primary-color); border-bottom-color: var(--primary-color); }
.tab-content.hidden { display: none; }
.tab-content h4 { font-size: 1.1rem; font-weight: 600; margin-bottom: 1rem; }
.tab-content h5 { font-size: 1rem; font-weight: 600; margin-top: 1.5rem; margin-bottom: 0.5rem; }
.tab-content p, .tab-content ul { color: var(--text-muted); font-size: 0.95rem; }
.tab-content ul { padding-left: 1.2rem; margin-bottom: 1.5rem; }

/* Tech Stack */
.tech-stack { margin-bottom: 2rem; }
.tech-items { display: flex; flex-wrap: wrap; gap: 0.75rem; }
.tech-item { display: flex; align-items: center; background: #ffffff; border: 1px solid var(--border-color); padding: 0.4rem 0.8rem; border-radius: 8px; font-size: 0.85rem; color: #374151; }
.tech-item i { margin-right: 0.5rem; font-size: 1.1rem; }

/* Buttons & Actions */
.project-actions { display: flex; flex-direction: column; gap: 1.5rem; }
.project-links { display: flex; gap: 0.75rem; flex-wrap: wrap; }
.btn {
    padding: 0.6rem 1.2rem; border: 1px solid transparent; border-radius: 8px;
    text-decoration: none; font-weight: 500; transition: all 0.2s ease;
    display: inline-flex; align-items: center; justify-content: center; gap: 0.6rem; font-size: 0.9rem;
}
.btn-primary { background: var(--primary-color); color: white; border-color: var(--primary-color); }
.btn-primary:hover { background: #0069d9; border-color: #0062cc;}
.btn-secondary { background: var(--secondary-color); color: white; border-color: var(--secondary-color); }
.btn-secondary:hover { background: #5a6268; border-color: #545b62; }
.btn-dark { background: var(--dark-color); color: white; border-color: var(--dark-color); }
.btn-dark:hover { background: #23272b; border-color: #1d2124;}
.btn-outline { background: var(--background-color); color: var(--text-color); border-color: var(--border-color); }
.btn-outline:hover { background: #f8f9fa; border-color: #d1d5db; }
.btn-outline .icon-notion { width: 1em; height: 1em; }
.pdf-link { margin-top: 1rem; align-self: flex-start; }

/* Demo Account */
.action-divider { border: none; border-top: 1px solid var(--border-color); }
.demo-guide-title { display: flex; align-items: center; gap: 0.5rem; font-size: 0.9rem; font-weight: 500; color: var(--text-muted); margin-bottom: 0.75rem; }
.credentials { display: flex; gap: 0.75rem; flex-wrap: wrap; }
.credential {
    background: transparent; color: var(--text-color); padding: 0.4rem 0.8rem;
    border-radius: 8px; font-size: 0.9rem;
    cursor: pointer; user-select: none; white-space: nowrap; border: 1px solid var(--border-color);
    transition: all 0.2s ease; display: flex; align-items: center; gap: 0.5rem;
}
.credential:hover { background: #eef2f7; border-color: #d1d5db; color: var(--primary-color); }

/* Footer */
.main-footer { text-align: center; padding: 3rem 1.5rem; border-top: 1px solid var(--border-color); }
.contact-items { display: flex; justify-content: center; align-items: center; gap: 2.5rem; flex-wrap: wrap; }
.contact-item { color: var(--text-muted); font-size: 1rem; text-decoration: none; display: flex; align-items: center; gap: 0.6rem; transition: color 0.2s ease; }
.contact-item:hover { color: var(--primary-color); }
.contact-item i { font-size: 1.3rem; }

/* Copy Notification */
.copy-notification { position: fixed; bottom: 20px; left: 50%; transform: translateX(-50%); background: #333; color: white; padding: 0.8rem 1.5rem; border-radius: 8px; font-size: 0.9rem; z-index: 1000; opacity: 0; transition: all 0.4s ease-in-out; }
.copy-notification.show { opacity: 1; bottom: 40px; }

/* Responsive */
@media (min-width: 820px) { .project-card { grid-template-columns: 1fr 1fr; gap: 2.5rem; align-items: start; } }
@media (max-width: 900px) { .side-nav { display: none; } }
@media (max-width: 768px) {
    .header { padding: 5rem 1.5rem; }
    .header h1 { font-size: 2.5rem; }
    .header .role, .btn-cta { font-size: 1rem; }
    .contact-items { flex-direction: column; gap: 1.5rem; }
    .project-card { padding: 1.5rem; }
}

/* Tech Icon SVG Style */
.tech-item .svg-icon {
    width: 1.1rem;
    height: 1.1rem;
    margin-right: 0.5rem;
}


.account-row {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 0.5rem;
}
.account-row:last-child {
    margin-bottom: 0;
}
.account-label {
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-color);
    min-width: 3rem;
    text-align: left;
}
.account-row .credentials {
    gap: 0.5rem;
}