/* ═══════════════════════════════════════════
   Variables & Reset
═══════════════════════════════════════════ */
:root {
    --accent: #1a3a5c;
    --accent-light: #2a5a8c;
    --text: #1c1c1c;
    --text-muted: #555;
    --border: #d8dde3;
    --bg: #ffffff;
    --bg-alt: #f5f7fa;
    --tag-bg: #e8eef5;
    --tag-text: #1a3a5c;
    --radius: 6px;
    --max-width: 900px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
    font-size: 16px;
    line-height: 1.6;
    color: var(--text);
    background: var(--bg);
}

/* ═══════════════════════════════════════════
   Header & Nav
═══════════════════════════════════════════ */
header {
    background: var(--accent);
    color: #fff;
    padding: 2.5rem 1.5rem 0;
}

.header-inner {
    max-width: var(--max-width);
    margin: 0 auto;
}

header h1 {
    font-size: 2.25rem;
    font-weight: 700;
    letter-spacing: -0.02em;
}

.tagline {
    font-size: 1.1rem;
    opacity: 0.85;
    margin-top: 0.25rem;
}

.github-link {
    display: inline-block;
    color: #a8c8e8;
    font-size: 0.9rem;
    text-decoration: none;
    margin-top: 0.4rem;
}

.github-link:hover {
    color: #fff;
    text-decoration: underline;
}

nav {
    max-width: var(--max-width);
    margin: 1.5rem auto 0;
    display: flex;
    gap: 0;
    border-top: 1px solid rgba(255,255,255,0.15);
}

nav a {
    color: rgba(255,255,255,0.75);
    text-decoration: none;
    padding: 0.65rem 1.25rem;
    font-size: 0.9rem;
    font-weight: 500;
    letter-spacing: 0.02em;
    transition: color 0.15s, background 0.15s;
}

nav a:hover {
    color: #fff;
    background: rgba(255,255,255,0.08);
}

/* ═══════════════════════════════════════════
   Main layout
═══════════════════════════════════════════ */
main {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 1.5rem 3rem;
}

section {
    padding-top: 3rem;
    border-bottom: 1px solid var(--border);
    padding-bottom: 2.5rem;
}

section:last-child {
    border-bottom: none;
}

section h2 {
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--accent);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: 1.5rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--accent);
    display: inline-block;
}

/* ═══════════════════════════════════════════
   Skills
═══════════════════════════════════════════ */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    gap: 1.5rem;
}

.skill-group h3 {
    font-size: 0.8rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--text-muted);
    margin-bottom: 0.6rem;
}

.skill-group ul {
    list-style: none;
}

.skill-group ul li {
    font-size: 0.95rem;
    padding: 0.2rem 0;
    color: var(--text);
}

.skill-group ul li::before {
    content: "▸ ";
    color: var(--accent-light);
    font-size: 0.75rem;
}

/* ═══════════════════════════════════════════
   Project Cards
═══════════════════════════════════════════ */
.project-card {
    background: var(--bg-alt);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.25rem 1.5rem;
    margin-bottom: 1.25rem;
}

.project-card.featured {
    border-left: 4px solid var(--accent);
}

.project-header {
    display: flex;
    align-items: baseline;
    justify-content: space-between;
    gap: 1rem;
    flex-wrap: wrap;
    margin-bottom: 0.6rem;
}

.project-card.featured .project-header h3 {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--accent);
}

.project-card.minor .project-header h4,
.project-card.archive .project-header h4 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--accent);
}

.project-card.archive {
    opacity: 0.8;
}

.project-links {
    display: flex;
    gap: 0.75rem;
    flex-shrink: 0;
}

.project-links a {
    font-size: 0.85rem;
    color: var(--accent-light);
    text-decoration: none;
    font-weight: 500;
}

.project-links a:hover {
    text-decoration: underline;
}

.project-card p {
    font-size: 0.95rem;
    color: var(--text);
    margin-bottom: 0.85rem;
    line-height: 1.65;
}

.project-card code {
    font-family: "Cascadia Code", "Fira Code", "Consolas", monospace;
    font-size: 0.88em;
    background: var(--border);
    padding: 0.1em 0.35em;
    border-radius: 3px;
}

.tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
}

.tags span {
    background: var(--tag-bg);
    color: var(--tag-text);
    font-size: 0.78rem;
    font-weight: 600;
    padding: 0.2rem 0.55rem;
    border-radius: 3px;
    letter-spacing: 0.02em;
}

.subsection-label {
    font-size: 0.85rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--text-muted);
    margin: 2rem 0 1rem;
}

.project-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: 1rem;
}

.project-list .project-card {
    margin-bottom: 0;
}

.archive-badge {
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    background: #e8e8e8;
    color: #666;
    padding: 0.15rem 0.4rem;
    border-radius: 3px;
    vertical-align: middle;
    margin-left: 0.4rem;
}

/* ═══════════════════════════════════════════
   Summary
═══════════════════════════════════════════ */
.summary-text {
    font-size: 1rem;
    line-height: 1.75;
    color: var(--text);
    max-width: 720px;
}

/* ═══════════════════════════════════════════
   Certifications
═══════════════════════════════════════════ */
.cert-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 0.75rem;
}

.cert-card {
    background: var(--bg-alt);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 0.85rem 1rem;
}

.cert-name {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text);
    margin-bottom: 0.25rem;
}

.cert-meta {
    font-size: 0.82rem;
    color: var(--text-muted);
}

/* ═══════════════════════════════════════════
   Experience & Education
═══════════════════════════════════════════ */
.experience-entry,
.education-entry {
    margin-bottom: 2rem;
}

.experience-entry:last-child,
.education-entry:last-child {
    margin-bottom: 0;
}

.entry-header {
    display: flex;
    align-items: baseline;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 0.25rem;
}

.entry-header h3 {
    font-size: 1.05rem;
    font-weight: 700;
    color: var(--text);
}

.entry-date {
    font-size: 0.85rem;
    color: var(--text-muted);
    white-space: nowrap;
}

.entry-org {
    font-size: 0.95rem;
    color: var(--accent-light);
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.entry-body ul {
    padding-left: 1.25rem;
    font-size: 0.95rem;
    line-height: 1.7;
}

.placeholder-notice {
    color: var(--text-muted);
    font-style: italic;
    font-size: 0.95rem;
}

/* ═══════════════════════════════════════════
   Footer
═══════════════════════════════════════════ */
footer {
    background: var(--bg-alt);
    border-top: 1px solid var(--border);
    text-align: center;
    padding: 1.5rem;
    font-size: 0.9rem;
    color: var(--text-muted);
}

footer a {
    color: var(--accent-light);
    text-decoration: none;
}

footer a:hover {
    text-decoration: underline;
}

/* ═══════════════════════════════════════════
   Responsive
═══════════════════════════════════════════ */
@media (max-width: 600px) {
    header h1 { font-size: 1.75rem; }
    nav a { padding: 0.6rem 0.9rem; font-size: 0.85rem; }
    .skills-grid { grid-template-columns: 1fr 1fr; }
    .project-list { grid-template-columns: 1fr; }
    .project-header { flex-direction: column; align-items: flex-start; }
    .entry-header { flex-direction: column; }
}