@import url('https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@300;400;500;600;700&family=IBM+Plex+Sans:wght@300;400;500&family=IBM+Plex+Mono:wght@300;400;500&display=swap');

/* ─── Design Tokens ─────────────────────────────────── */
:root {
  --primary:    #E6F3FF;
  --secondary:  #6A8AA8;
  --tertiary:   #4FD6E0;
  --neutral:    #050A14;
  --surface:    #0A1220;
  --surface-2:  #0E1A2E;
  --border:     rgba(106, 138, 168, 0.2);

  --font-display: 'Space Grotesk', sans-serif;
  --font-body:    'IBM Plex Sans', sans-serif;
  --font-mono:    'IBM Plex Mono', monospace;

  --radius-sm: 2px;
  --radius-md: 4px;
  --radius-lg: 8px;

  --transition: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ─── Reset & Base ───────────────────────────────────── */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html { scroll-behavior: smooth; }

body {
  background-color: var(--neutral);
  color: var(--primary);
  font-family: var(--font-body);
  font-size: 0.92rem;
  line-height: 1.55;
  padding-top: 48px;
  padding-bottom: 80px;
  min-height: 100vh;
  /* subtle grid texture */
  background-image:
    linear-gradient(rgba(79,214,224,0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(79,214,224,0.03) 1px, transparent 1px);
  background-size: 40px 40px;
}

/* ─── Layout ─────────────────────────────────────────── */
#content {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ─── Autobio / Header ───────────────────────────────── */
#autobio {
  display: flex;
  align-items: flex-start;
  gap: 32px;
  padding-bottom: 40px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 40px;
  animation: fadeUp 0.6s ease both;
}

#portrait {
  width: 120px;
  height: 120px;
  object-fit: cover;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  display: block;
  flex-shrink: 0;
  filter: grayscale(20%) contrast(1.05);
}

#personal {
  flex: 1;
}

#personal h1 {
  font-family: var(--font-display);
  font-size: 2.6rem;
  font-weight: 500;
  letter-spacing: -0.02em;
  color: var(--primary);
  line-height: 1.1;
  margin-bottom: 10px;
}

#personal > p {
  color: var(--secondary);
  font-size: 0.92rem;
  max-width: 560px;
  margin-bottom: 20px;
  line-height: 1.55;
}

/* ─── Navigation Links ───────────────────────────────── */
ul#links {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
}

ul#links li,
ul#links li a {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--secondary);
  text-decoration: none;
  padding: 6px 14px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition);
  display: inline-block;
  background: transparent;
}

ul#links li:hover,
ul#links li a:hover {
  color: var(--tertiary);
  border-color: var(--tertiary);
  background: rgba(79, 214, 224, 0.06);
}

ul#links li.active {
  color: var(--tertiary);
  border-color: var(--tertiary);
  background: rgba(79, 214, 224, 0.08);
}

/* ─── Content Container ──────────────────────────────── */
#content_container {
  transition: opacity 0.3s ease;
  min-height: 300px;
}

#content_container h2.welcome-heading {
  font-family: var(--font-display);
  font-size: 1.85rem;
  font-weight: 500;
  color: var(--primary);
  margin-bottom: 12px;
}

#content_container > p {
  color: var(--secondary);
}

/* ─── Markdown Content Styles ────────────────────────── */
#content_container h1 {
  font-family: var(--font-display);
  font-size: 1.85rem;
  font-weight: 500;
  letter-spacing: -0.01em;
  color: var(--primary);
  margin-bottom: 24px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border);
}

#content_container h2 {
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 500;
  color: var(--primary);
  margin: 32px 0 12px;
}

#content_container h3 {
  font-family: var(--font-display);
  font-size: 1rem;
  font-weight: 500;
  color: var(--secondary);
  margin: 20px 0 8px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

#content_container h4,
#content_container h5,
#content_container h6 {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 500;
  color: var(--tertiary);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin: 16px 0 6px;
}

#content_container p {
  color: var(--primary);
  margin-bottom: 12px;
  line-height: 1.6;
}

#content_container ul,
#content_container ol {
  margin: 0 0 16px 20px;
  color: var(--primary);
}

#content_container li {
  margin-bottom: 8px;
  line-height: 1.55;
}

#content_container a {
  color: var(--tertiary);
  text-decoration: none;
  border-bottom: 1px solid rgba(79, 214, 224, 0.3);
  transition: border-color var(--transition);
}

#content_container a:hover {
  border-color: var(--tertiary);
}

#content_container strong, b {
  color: var(--primary);
  font-weight: 500;
}

#content_container code,
#content_container pre {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 2px 6px;
  color: var(--tertiary);
}

#content_container pre {
  padding: 16px;
  overflow-x: auto;
  margin: 16px 0;
}

#content_container hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 24px 0;
}

/* ─── Images ─────────────────────────────────────────── */
#content_container img {
  max-width: 100%;
  height: auto;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  margin: 16px 0 4px;
  display: block;
}

/* ─── Caption ────────────────────────────────────────── */
#caption,
center#caption {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.1em;
  color: var(--secondary);
  text-align: center;
  margin-bottom: 16px;
  text-transform: uppercase;
}

/* ─── Details / Summary (Projects) ──────────────────── */
#content_container details {
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  margin-bottom: 16px;
  overflow: hidden;
  background: var(--surface);
}

#content_container summary {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--secondary);
  padding: 14px 18px;
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  gap: 10px;
  transition: color var(--transition), background var(--transition);
}

#content_container summary::before {
  content: '▶';
  font-size: 0.55rem;
  color: var(--tertiary);
  transition: transform var(--transition);
}

#content_container details[open] summary::before {
  transform: rotate(90deg);
}

#content_container summary:hover {
  color: var(--tertiary);
  background: rgba(79, 214, 224, 0.04);
}

#content_container details > *:not(summary) {
  padding: 0 18px 18px;
}

/* ─── Contact Form ───────────────────────────────────── */
#contact-form {
  max-width: 560px;
}

#contact-form label,
#contact-form > *:not(input):not(textarea):not(br) {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--secondary);
  display: block;
  margin-bottom: 4px;
  margin-top: 16px;
}

#contact-form input[type="text"],
#contact-form textarea {
  width: 100%;
  padding: 10px 14px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  color: var(--primary);
  font-family: var(--font-body);
  font-size: 0.92rem;
  outline: none;
  transition: border-color var(--transition), box-shadow var(--transition);
  resize: vertical;
}

#contact-form input[type="text"]:focus,
#contact-form textarea:focus {
  border-color: var(--tertiary);
  box-shadow: 0 0 0 2px rgba(79, 214, 224, 0.12);
}

#contact-form input[type="submit"] {
  margin-top: 16px;
  padding: 10px 24px;
  background: transparent;
  border: 1px solid var(--tertiary);
  border-radius: var(--radius-md);
  color: var(--tertiary);
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  cursor: pointer;
  transition: background var(--transition), color var(--transition);
}

#contact-form input[type="submit"]:hover {
  background: rgba(79, 214, 224, 0.1);
}

/* ─── Footer ─────────────────────────────────────────── */
#footer {
  margin-top: 60px;
  padding-top: 20px;
  border-top: 1px solid var(--border);
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--secondary);
  opacity: 0.6;
}

#footer a {
  color: var(--secondary);
  text-decoration: none;
  border-bottom: 1px solid var(--border);
  transition: color var(--transition);
}

#footer a:hover { color: var(--tertiary); }

/* ─── Animations ─────────────────────────────────────── */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(12px); }
  to   { opacity: 1; transform: translateY(0); }
}

.fade-in {
  animation: fadeUp 0.45s ease both;
}

/* ─── Responsive ─────────────────────────────────────── */
@media (max-width: 640px) {
  body { padding-top: 28px; }

  #autobio {
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 20px;
  }

  #portrait {
    width: 100px;
    height: 100px;
  }

  #personal h1 { font-size: 1.9rem; }

  ul#links {
    justify-content: center;
  }

  #contact-form { max-width: 100%; }
}