@import url('https://cdn.jsdelivr.net/gh/orioncactus/pretendard/dist/web/static/pretendard.css');
@import url('https://fonts.googleapis.com/css2?family=JetBrains+Mono:wght@400;500;600&display=swap');

:root {
    --bg-base: #ffffff;
    --bg-surface: #f8fafc;
    --bg-card: #ffffff;
    --bg-card-hover: #f1f8f3;
    --bg-elevated: #e2e8f0;
    --border-subtle: #e2e8f0;
    --border-green: rgba(22, 163, 74, 0.25);
    --border-green-hover: rgba(22, 163, 74, 0.55);
    
    --text-primary: #0f172a;
    --text-secondary: #334155;
    --text-muted: #64748b;
    
    --primary: #16a34a;       /* Crisp Emerald Green */
    --primary-hover: #15803d; /* Forest Green */
    --primary-light: #22c55e;
    --primary-soft: #dcfce7;  /* Soft Mint Green Badge BG */
    --primary-border: #bbf7d0;
    
    --font-sans: -apple-system, BlinkMacSystemFont, "Pretendard", "SF Pro Text", Roboto, sans-serif;
    --font-heading: -apple-system, BlinkMacSystemFont, "Pretendard", "SF Pro Display", sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
    
    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 18px;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 14px rgba(0, 0, 0, 0.06);
    --shadow-hover: 0 10px 25px rgba(22, 163, 74, 0.12);
}

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

html {
    scroll-behavior: smooth;
    font-size: 15px;
}

body {
    background-color: var(--bg-base);
    color: var(--text-primary);
    font-family: var(--font-sans);
    line-height: 1.55;
    letter-spacing: -0.015em;
    overflow-x: hidden;
}

.container {
    max-width: 1040px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ==========================================================================
   Navigation Bar (Crisp White + Subtle Border)
   ========================================================================== */
.navbar {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: saturate(180%) blur(16px);
    -webkit-backdrop-filter: saturate(180%) blur(16px);
    border-bottom: 1px solid var(--border-subtle);
    height: 52px;
    display: flex;
    align-items: center;
}

.nav-container {
    width: 100%;
    max-width: 1040px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    color: var(--text-primary);
    font-weight: 700;
    font-size: 0.95rem;
    letter-spacing: -0.02em;
}

.brand-logo-img {
    width: 26px;
    height: 26px;
    border-radius: 6px;
    object-fit: cover;
    display: block;
    box-shadow: var(--shadow-sm);
    transition: transform 0.2s ease;
}

.nav-brand:hover .brand-logo-img {
    transform: scale(1.08);
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 28px;
    list-style: none;
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.88rem;
    font-weight: 500;
    letter-spacing: -0.01em;
    transition: color 0.15s ease;
}

.nav-link:hover {
    color: var(--primary);
}

.nav-cta {
    background: var(--primary);
    color: #ffffff !important;
    font-size: 0.8rem;
    font-weight: 600;
    padding: 6px 14px;
    border-radius: 999px;
    text-decoration: none;
    transition: background-color 0.2s ease, transform 0.15s ease;
}

.nav-cta:hover {
    background: var(--primary-hover);
    transform: translateY(-1px);
}

/* ==========================================================================
   Hero Section (Compact & Centered Portrait)
   ========================================================================== */
.hero-section {
    padding: 48px 0 40px;
    text-align: center;
    background: radial-gradient(circle at 50% 20%, rgba(22, 163, 74, 0.05) 0%, transparent 70%);
}

.hero-eyebrow {
    font-size: 0.82rem;
    font-weight: 700;
    color: var(--primary);
    text-transform: uppercase;
    letter-spacing: 0.06em;
    margin-bottom: 8px;
    display: inline-block;
    background: var(--primary-soft);
    padding: 4px 12px;
    border-radius: 999px;
    border: 1px solid var(--primary-border);
}

.hero-title {
    font-family: var(--font-heading);
    font-size: 2.6rem;
    font-weight: 800;
    letter-spacing: -0.03em;
    line-height: 1.15;
    color: var(--text-primary);
    margin-bottom: 6px;
}

.hero-headline {
    font-family: var(--font-heading);
    font-size: 1.35rem;
    font-weight: 600;
    letter-spacing: -0.02em;
    color: var(--text-secondary);
    margin-bottom: 10px;
}

.hero-subcopy {
    font-size: 0.95rem;
    color: var(--text-muted);
    max-width: 600px;
    margin: 0 auto 22px;
    line-height: 1.5;
}

.hero-links {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 14px;
    margin-bottom: 30px;
    flex-wrap: wrap;
}

.btn-pill-primary {
    background: var(--primary);
    color: #ffffff;
    font-size: 0.86rem;
    font-weight: 600;
    padding: 9px 20px;
    border-radius: 999px;
    text-decoration: none;
    box-shadow: 0 3px 10px rgba(22, 163, 74, 0.25);
    transition: background-color 0.2s ease, transform 0.15s ease;
}

.btn-pill-primary:hover {
    background: var(--primary-hover);
    transform: translateY(-1px);
}

.btn-pill-secondary {
    background: #ffffff;
    color: var(--text-primary);
    font-size: 0.86rem;
    font-weight: 600;
    padding: 8px 18px;
    border-radius: 999px;
    text-decoration: none;
    border: 1px solid var(--border-subtle);
    display: inline-flex;
    align-items: center;
    gap: 5px;
    transition: border-color 0.2s ease, color 0.2s ease;
}

.btn-pill-secondary:hover {
    border-color: var(--primary);
    color: var(--primary);
}

/* Center Portrait Stage */
.portrait-stage {
    position: relative;
    display: inline-block;
    margin: 0 auto 30px;
}

.portrait-frame {
    width: 250px;
    height: 300px;
    border-radius: 18px;
    overflow: hidden;
    margin: 0 auto;
    border: 2px solid rgba(22, 163, 74, 0.35);
    box-shadow: 0 14px 32px rgba(0, 0, 0, 0.08), 0 0 0 6px rgba(22, 163, 74, 0.06);
    background: #ffffff;
}

.portrait-img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: center 25%;
    display: block;
}

.floating-badge {
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    background: #ffffff;
    border: 1px solid var(--primary-border);
    border-radius: 999px;
    padding: 4px 13px;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 0.76rem;
    font-weight: 600;
    color: var(--primary);
    box-shadow: var(--shadow-sm);
    white-space: nowrap;
}

.floating-badge .dot {
    width: 7px;
    height: 7px;
    background: var(--primary);
    border-radius: 50%;
    display: inline-block;
}

/* Specs Bar (Compact 4-column) */
.specs-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 12px;
    max-width: 860px;
    margin: 0 auto;
    padding: 16px 20px;
    background: #ffffff;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
}

.spec-item {
    text-align: center;
}

.spec-value {
    font-family: var(--font-heading);
    font-size: 1.7rem;
    font-weight: 800;
    color: var(--primary);
    line-height: 1.1;
    letter-spacing: -0.03em;
}

.spec-label {
    font-size: 0.74rem;
    font-weight: 500;
    color: var(--text-muted);
    margin-top: 3px;
}

/* ==========================================================================
   Section Headers (Compact & Clean)
   ========================================================================== */
.section {
    padding: 55px 0;
}

.section-alt {
    padding: 55px 0;
    background: var(--bg-surface);
    border-top: 1px solid var(--border-subtle);
    border-bottom: 1px solid var(--border-subtle);
}

.section-header {
    text-align: center;
    max-width: 620px;
    margin: 0 auto 32px;
}

.section-eyebrow {
    font-size: 0.76rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--primary);
    display: block;
    margin-bottom: 5px;
}

.section-title {
    font-family: var(--font-heading);
    font-size: 1.85rem;
    font-weight: 800;
    letter-spacing: -0.025em;
    color: var(--text-primary);
    margin-bottom: 6px;
}

.section-sub {
    font-size: 0.88rem;
    color: var(--text-muted);
    line-height: 1.45;
}

/* ==========================================================================
   Tech Articles / Deep Dive Cards (Compact 3-Grid)
   ========================================================================== */
.articles-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
}

.article-card {
    background: #ffffff;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    padding: 20px 18px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    box-shadow: var(--shadow-sm);
    transition: transform 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
}

.article-card:hover {
    transform: translateY(-3px);
    border-color: var(--border-green-hover);
    box-shadow: var(--shadow-hover);
}

.article-badge-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 10px;
}

.article-category {
    font-size: 0.7rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.04em;
    color: var(--primary);
    background: var(--primary-soft);
    padding: 3px 8px;
    border-radius: 999px;
}

.article-source-tag {
    font-size: 0.7rem;
    color: var(--text-muted);
    display: inline-flex;
    align-items: center;
    gap: 4px;
}

.article-title {
    font-family: var(--font-heading);
    font-size: 1.1rem;
    font-weight: 700;
    line-height: 1.35;
    color: var(--text-primary);
    margin-bottom: 10px;
}

.article-points {
    list-style: none;
    margin-bottom: 14px;
    font-size: 0.82rem;
    color: var(--text-secondary);
}

.article-points li {
    position: relative;
    padding-left: 12px;
    margin-bottom: 5px;
    line-height: 1.4;
}

.article-points li::before {
    content: "•";
    color: var(--primary);
    position: absolute;
    left: 0;
    font-weight: bold;
}

.article-tags-wrap {
    display: flex;
    flex-wrap: wrap;
    gap: 4px;
    margin-bottom: 16px;
}

.article-tag {
    font-family: var(--font-mono);
    font-size: 0.68rem;
    color: var(--text-secondary);
    background: #f1f5f9;
    padding: 2px 6px;
    border-radius: 4px;
}

.article-notion-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    background: #ffffff;
    color: var(--primary);
    border: 1px solid var(--primary);
    font-size: 0.8rem;
    font-weight: 600;
    padding: 7px 12px;
    border-radius: 999px;
    text-decoration: none;
    transition: background-color 0.2s ease, color 0.2s ease;
}

.article-notion-btn:hover {
    background: var(--primary);
    color: #ffffff;
}

/* ==========================================================================
   Project Cards (Compact Bento List)
   ========================================================================== */
.projects-list {
    display: flex;
    flex-direction: column;
    gap: 18px;
}

.project-card {
    background: #ffffff;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    padding: 22px 24px;
    box-shadow: var(--shadow-sm);
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.project-card:hover {
    border-color: var(--border-green-hover);
    box-shadow: var(--shadow-hover);
}

.project-card-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 10px;
    flex-wrap: wrap;
    gap: 6px;
}

.project-category-badge {
    font-size: 0.7rem;
    font-weight: 700;
    color: var(--primary);
    background: var(--primary-soft);
    padding: 3px 9px;
    border-radius: 999px;
    display: inline-block;
    margin-right: 6px;
}

.project-period {
    font-size: 0.72rem;
    color: var(--text-muted);
    font-family: var(--font-mono);
}

.project-title {
    font-family: var(--font-heading);
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--text-primary);
    margin: 3px 0 2px;
}

.project-subtitle {
    font-size: 0.84rem;
    color: var(--text-secondary);
}

.project-overview {
    font-size: 0.86rem;
    color: var(--text-secondary);
    line-height: 1.45;
    margin-bottom: 12px;
    background: var(--bg-surface);
    padding: 10px 14px;
    border-radius: var(--radius-sm);
    border-left: 3px solid var(--primary);
}

.project-tech-chips {
    display: flex;
    flex-wrap: wrap;
    gap: 5px;
    margin-bottom: 14px;
}

.tech-chip {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    font-weight: 500;
    background: #f1f5f9;
    color: var(--text-secondary);
    padding: 2px 8px;
    border-radius: 999px;
    border: 1px solid #e2e8f0;
}

.project-grid-two {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 14px;
}

.project-box {
    background: #ffffff;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-sm);
    padding: 12px 14px;
}

.project-box-title {
    font-size: 0.76rem;
    font-weight: 700;
    color: var(--primary);
    text-transform: uppercase;
    letter-spacing: 0.04em;
    margin-bottom: 6px;
}

.compact-list {
    list-style: none;
    font-size: 0.82rem;
    color: var(--text-secondary);
}

.compact-list li {
    position: relative;
    padding-left: 14px;
    margin-bottom: 4px;
    line-height: 1.35;
}

.compact-list li::before {
    content: "✓";
    position: absolute;
    left: 0;
    color: var(--primary);
    font-weight: bold;
    font-size: 0.78rem;
}

/* ==========================================================================
   Skills Grid (Compact)
   ========================================================================== */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 14px;
}

.skill-card {
    background: #ffffff;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    padding: 16px 18px;
    box-shadow: var(--shadow-sm);
}

.skill-category-title {
    font-size: 0.88rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 6px;
}

.skill-category-title .bullet {
    width: 6px;
    height: 6px;
    background: var(--primary);
    border-radius: 50%;
}

.skill-item-compact {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 6px 0;
    border-bottom: 1px solid #f1f5f9;
    font-size: 0.8rem;
}

.skill-item-compact:last-child {
    border-bottom: none;
}

.skill-name {
    font-weight: 600;
    color: var(--text-primary);
}

.skill-tag {
    font-size: 0.68rem;
    font-family: var(--font-mono);
    color: var(--primary);
    background: var(--primary-soft);
    padding: 2px 6px;
    border-radius: 4px;
}

/* ==========================================================================
   Infrastructure Topology (Compact Flow)
   ========================================================================== */
.infra-flow {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: #ffffff;
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    padding: 20px 24px;
    box-shadow: var(--shadow-sm);
    flex-wrap: wrap;
    gap: 10px;
}

.infra-step {
    flex: 1;
    min-width: 130px;
    text-align: center;
    padding: 8px;
    border-radius: var(--radius-sm);
    background: var(--bg-surface);
    border: 1px solid var(--border-subtle);
}

.infra-step-icon {
    font-size: 1.2rem;
    margin-bottom: 3px;
}

.infra-step-name {
    font-size: 0.82rem;
    font-weight: 700;
    color: var(--text-primary);
}

.infra-step-desc {
    font-size: 0.7rem;
    color: var(--text-muted);
    font-family: var(--font-mono);
    margin-top: 2px;
}

.infra-arrow {
    color: var(--primary);
    font-weight: bold;
    font-size: 1rem;
}

/* ==========================================================================
   Footer
   ========================================================================== */
.footer {
    border-top: 1px solid var(--border-subtle);
    padding: 24px 0;
    background: #ffffff;
}

.footer-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 12px;
    font-size: 0.78rem;
    color: var(--text-muted);
}

.footer-brand {
    font-weight: 600;
    color: var(--text-primary);
}

/* Responsive */
@media (max-width: 900px) {
    .specs-grid { grid-template-columns: repeat(2, 1fr); }
    .articles-grid { grid-template-columns: 1fr; }
    .skills-grid { grid-template-columns: 1fr; }
    .project-grid-two { grid-template-columns: 1fr; }
    .infra-flow { flex-direction: column; }
    .infra-arrow { transform: rotate(90deg); margin: 3px 0; }
}

@media (max-width: 640px) {
    .nav-links { display: none; }
    .hero-title { font-size: 2.1rem; }
    .hero-headline { font-size: 1.15rem; }
    .portrait-frame { width: 210px; height: 250px; }
    .specs-grid { grid-template-columns: 1fr; }
}