/* ==========================================================================
   Design Tokens
   ========================================================================== */

:root {
  --bg: #0e1520;
  --bg-surface: #141e2d;
  --bg-elevated: #1a2638;
  --border: #233047;
  --border-light: #2e4060;
  --text: #e4eaf4;
  --text-muted: #7a90ad;
  --text-dim: #4a6080;
  --accent: #00c8f0;
  --accent-dim: rgba(0, 200, 240, 0.08);
  --accent-glow: 0 0 24px rgba(0, 200, 240, 0.2);
  --green: #10b981;
  --red: #f87171;
  --yellow: #fbbf24;
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', 'Cascadia Code', monospace;
  --max-width: 1140px;
  --radius: 6px;
  --nav-h: 64px;
  --ease: cubic-bezier(0.16, 1, 0.3, 1);
}

/* ==========================================================================
   Reset & Base
   ========================================================================== */

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg);
  color: var(--text);
  line-height: 1.6;
  overflow-x: hidden;
}

a {
  color: inherit;
  text-decoration: none;
}

ul {
  list-style: none;
}

/* ==========================================================================
   Utility
   ========================================================================== */

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 32px;
}

.mono {
  font-family: var(--font-mono);
}

.muted {
  color: var(--text-muted);
}

.comment {
  color: var(--text-dim);
}

/* ==========================================================================
   Navigation
   ========================================================================== */

#nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: var(--nav-h);
  transition: background 0.3s ease, border-color 0.3s ease;
  border-bottom: 1px solid transparent;
}

#nav.scrolled {
  background: rgba(8, 12, 16, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom-color: var(--border);
}

.nav-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 32px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 500;
  color: var(--accent);
  letter-spacing: -0.02em;
}

.cursor-blink {
  animation: blink 1.1s step-end infinite;
  color: var(--accent);
}

@keyframes blink {
  0%, 100% { opacity: 1; }
  50%       { opacity: 0; }
}

.nav-right {
  display: flex;
  align-items: center;
  gap: 28px;
}

.nav-links {
  display: flex;
  gap: 40px;
  align-items: center;
}

.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  background: none;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text-muted);
  cursor: pointer;
  transition: color 0.2s ease, border-color 0.2s ease;
  flex-shrink: 0;
}

.theme-toggle:hover {
  color: var(--accent);
  border-color: var(--accent);
}

/* Show sun in dark mode, moon in light mode */
.icon-moon { display: none; }
.icon-sun  { display: block; }

[data-theme="light"] .icon-moon { display: block; }
[data-theme="light"] .icon-sun  { display: none; }

.nav-links a {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--text-muted);
  transition: color 0.2s ease;
  letter-spacing: 0.02em;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--accent);
}

/* ==========================================================================
   Hero
   ========================================================================== */

#hero {
  position: relative;
  min-height: 100svh;
  display: flex;
  align-items: center;
  overflow: hidden;
  /* dot grid */
  background-image: radial-gradient(circle, var(--border-light) 1px, transparent 1px);
  background-size: 28px 28px;
}

.hero-glow {
  position: absolute;
  border-radius: 50%;
  pointer-events: none;
}

.hero-glow-1 {
  width: 700px;
  height: 700px;
  background: radial-gradient(circle, rgba(0, 200, 240, 0.055) 0%, transparent 65%);
  top: -200px;
  right: -180px;
  animation: drift 12s ease-in-out infinite alternate;
}

.hero-glow-2 {
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(16, 185, 129, 0.04) 0%, transparent 65%);
  bottom: -100px;
  left: -100px;
  animation: drift 16s ease-in-out infinite alternate-reverse;
}

@keyframes drift {
  from { transform: translate(0, 0) scale(1); }
  to   { transform: translate(30px, 20px) scale(1.08); }
}

.hero-content {
  position: relative;
  z-index: 1;
  padding-top: var(--nav-h);
}

.hero-label {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--text-muted);
  letter-spacing: 0.06em;
  margin-bottom: 20px;
}

.hero-name {
  display: flex;
  flex-direction: column;
  font-size: clamp(72px, 11vw, 148px);
  font-weight: 600;
  line-height: 0.92;
  letter-spacing: -0.04em;
  margin-bottom: 32px;
  gap: 4px;
}

.name-solid {
  color: var(--text);
}

.name-outline {
  -webkit-text-stroke: 1.5px rgba(221, 227, 236, 0.25);
  color: transparent;
  /* subtle gradient in the stroke */
  background: linear-gradient(135deg, rgba(0, 200, 240, 0.4), transparent 60%);
  -webkit-background-clip: text;
  background-clip: text;
}

.hero-tagline {
  font-family: var(--font-mono);
  font-size: clamp(14px, 2vw, 18px);
  color: var(--text-muted);
  letter-spacing: 0.03em;
  margin-bottom: 44px;
  min-height: 1.6em;
}

.hero-cta {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  border-radius: var(--radius);
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.02em;
  transition: all 0.2s var(--ease);
  cursor: pointer;
  border: none;
}

.btn-primary {
  background: var(--accent);
  color: var(--bg);
}

.btn-primary:hover {
  background: #1fd6ff;
  box-shadow: var(--accent-glow);
  transform: translateY(-1px);
}

.btn-ghost {
  background: transparent;
  color: var(--text-muted);
  border: 1px solid var(--border-light);
}

.btn-ghost:hover {
  color: var(--text);
  border-color: var(--accent);
  box-shadow: inset 0 0 0 1px var(--accent);
}

/* Scroll hint */
.scroll-hint {
  position: absolute;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  color: var(--text-dim);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.scroll-line {
  width: 1px;
  height: 48px;
  background: linear-gradient(to bottom, var(--text-dim), transparent);
  animation: scroll-drop 2.4s ease-in-out infinite;
}

@keyframes scroll-drop {
  0%   { transform: scaleY(0); transform-origin: top; opacity: 0; }
  40%  { transform: scaleY(1); transform-origin: top; opacity: 1; }
  60%  { transform: scaleY(1); transform-origin: bottom; opacity: 1; }
  100% { transform: scaleY(0); transform-origin: bottom; opacity: 0; }
}

/* ==========================================================================
   Sections — shared
   ========================================================================== */

.section {
  padding: 120px 0;
}

.section-header {
  display: flex;
  align-items: baseline;
  gap: 16px;
  margin-bottom: 56px;
}

.section-num {
  font-size: 12px;
  color: var(--accent);
  letter-spacing: 0.06em;
  user-select: none;
}

.section-header h2 {
  font-size: clamp(32px, 5vw, 52px);
  font-weight: 600;
  letter-spacing: -0.03em;
  line-height: 1;
}

/* Section dividers */
.section + .section {
  border-top: 1px solid var(--border);
}

/* ==========================================================================
   Reveal Animations
   ========================================================================== */

.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.65s var(--ease), transform 0.65s var(--ease);
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

.reveal:nth-child(2) { transition-delay: 0.08s; }
.reveal:nth-child(3) { transition-delay: 0.16s; }
.reveal:nth-child(4) { transition-delay: 0.24s; }

/* ==========================================================================
   Experience
   ========================================================================== */

.exp-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.exp-item {
  padding: 24px;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: border-color 0.2s ease;
}

.exp-item:hover {
  border-color: var(--border-light);
}

.exp-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 16px;
  margin-bottom: 16px;
  flex-wrap: wrap;
}

.exp-left {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.exp-company {
  font-size: 16px;
  font-weight: 600;
  color: var(--text);
  letter-spacing: -0.01em;
}

.exp-role {
  font-size: 13px;
  color: var(--text-muted);
}

.exp-right {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 4px;
  flex-shrink: 0;
}

.exp-dates {
  font-size: 12px;
  color: var(--accent);
  letter-spacing: 0.02em;
}

.exp-location {
  font-size: 11px;
  color: var(--text-dim);
  letter-spacing: 0.04em;
}

.exp-bullets {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.exp-bullets li {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.65;
  padding-left: 20px;
  position: relative;
}

.exp-bullets li::before {
  content: '→';
  position: absolute;
  left: 0;
  color: var(--accent);
  font-size: 12px;
  font-family: var(--font-mono);
  top: 2px;
}

/* ==========================================================================
   Education
   ========================================================================== */

.edu-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 16px;
}

.edu-item {
  padding: 24px;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: border-color 0.2s ease;
}

.edu-item:hover {
  border-color: var(--border-light);
}

.edu-degree {
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
  letter-spacing: -0.01em;
  margin-bottom: 4px;
}

.edu-school {
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 14px;
}

.edu-meta {
  display: flex;
  gap: 16px;
  align-items: center;
}

.edu-dates {
  font-size: 11px;
  color: var(--accent);
  letter-spacing: 0.04em;
}

.edu-gpa {
  font-size: 11px;
  color: var(--text-dim);
  letter-spacing: 0.04em;
}

/* ==========================================================================
   Projects
   ========================================================================== */

.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 20px;
}

.project-card {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: border-color 0.25s ease, transform 0.25s var(--ease), box-shadow 0.25s ease;
}

.project-card:hover {
  border-color: rgba(0, 200, 240, 0.35);
  transform: translateY(-4px);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.4), var(--accent-glow);
}

.terminal-bar {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 16px;
  background: var(--bg-elevated);
  border-bottom: 1px solid var(--border);
}

.terminal-dots {
  display: flex;
  gap: 6px;
  flex-shrink: 0;
}

.dot {
  width: 11px;
  height: 11px;
  border-radius: 50%;
}

.dot-red    { background: var(--red); opacity: 0.7; }
.dot-yellow { background: var(--yellow); opacity: 0.7; }
.dot-green  { background: var(--green); opacity: 0.7; }

.terminal-path {
  font-size: 11px;
  color: var(--text-dim);
  letter-spacing: 0.02em;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.card-body {
  padding: 24px;
  display: flex;
  flex-direction: column;
  flex: 1;
}

.card-body h3 {
  font-size: 17px;
  font-weight: 600;
  letter-spacing: -0.02em;
  margin-bottom: 10px;
  color: var(--text);
}

.card-body p {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.65;
  margin-bottom: 20px;
  flex: 1;
}

.tech-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 20px;
}

.tech-tags span {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--accent);
  background: var(--accent-dim);
  border: 1px solid rgba(0, 200, 240, 0.15);
  padding: 3px 9px;
  border-radius: 3px;
  letter-spacing: 0.02em;
}

.card-links {
  display: flex;
  gap: 16px;
  margin-top: auto;
}

.link-arrow {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--text-muted);
  transition: color 0.2s ease;
}

.link-arrow:hover {
  color: var(--accent);
}

.link-arrow.muted {
  color: var(--text-dim);
}

.link-arrow.muted:hover {
  color: var(--text-muted);
}

/* ==========================================================================
   Skills
   ========================================================================== */

.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 16px;
}

.skill-group {
  padding: 24px;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: border-color 0.2s ease;
}

.skill-group:hover {
  border-color: var(--border-light);
}

.skill-category {
  font-size: 11px;
  font-weight: 500;
  color: var(--accent);
  letter-spacing: 0.1em;
  text-transform: lowercase;
  margin-bottom: 16px;
}

.skill-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.skill-tags span {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--text-muted);
  background: var(--bg);
  border: 1px solid var(--border);
  padding: 4px 10px;
  border-radius: 3px;
  letter-spacing: 0.01em;
  transition: color 0.15s ease, border-color 0.15s ease;
}

.skill-tags span:hover {
  color: var(--text);
  border-color: var(--border-light);
}

/* ==========================================================================
   Certifications
   ========================================================================== */

.certs-row {
  margin-top: 20px;
  padding: 24px;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.certs-row .skill-category {
  margin-bottom: 20px;
}

.certs-list {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.cert-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 16px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
  cursor: pointer;
}

.cert-item:hover {
  border-color: rgba(0, 200, 240, 0.35);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.3);
}

.cert-item:hover .cert-name {
  color: var(--text);
}

.cert-arrow {
  font-size: 13px;
  color: var(--text-dim);
  margin-left: auto;
  transition: transform 0.2s var(--ease), color 0.2s ease;
}

.cert-item:hover .cert-arrow {
  transform: translate(2px, -2px);
  color: var(--accent);
}

.cert-provider {
  font-size: 10px;
  font-weight: 500;
  color: var(--accent);
  background: var(--accent-dim);
  border: 1px solid rgba(0, 200, 240, 0.15);
  padding: 2px 7px;
  border-radius: 3px;
  letter-spacing: 0.06em;
  flex-shrink: 0;
}

.cert-name {
  font-size: 13px;
  color: var(--text-muted);
  letter-spacing: 0.01em;
  transition: color 0.2s ease;
}

/* ==========================================================================
   Contact
   ========================================================================== */

.contact-sub {
  font-size: clamp(15px, 2vw, 18px);
  color: var(--text-muted);
  line-height: 1.7;
  max-width: 480px;
  margin-bottom: 48px;
}

.contact-list {
  display: flex;
  flex-direction: column;
  border-top: 1px solid var(--border);
}

.contact-row {
  display: grid;
  grid-template-columns: 100px 1fr auto;
  align-items: center;
  gap: 24px;
  padding: 22px 0;
  border-bottom: 1px solid var(--border);
  transition: background 0.15s ease;
  cursor: pointer;
}

.contact-row:hover .contact-val {
  color: var(--accent);
}

.contact-row:hover .contact-arrow {
  transform: translate(2px, -2px);
  color: var(--accent);
}

.contact-label {
  font-size: 11px;
  color: var(--text-dim);
  letter-spacing: 0.08em;
  text-transform: lowercase;
}

.contact-val {
  font-size: 15px;
  color: var(--text);
  transition: color 0.2s ease;
}

.contact-arrow {
  font-size: 16px;
  color: var(--text-dim);
  transition: transform 0.2s var(--ease), color 0.2s ease;
}

/* ==========================================================================
   Footer
   ========================================================================== */

footer {
  border-top: 1px solid var(--border);
  padding: 32px 0;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
  color: var(--text-muted);
  letter-spacing: 0.03em;
}

/* ==========================================================================
   Responsive
   ========================================================================== */

@media (max-width: 768px) {
  .container {
    padding: 0 20px;
  }

  .section {
    padding: 80px 0;
  }

  .nav-links {
    gap: 24px;
  }

  .hero-name {
    margin-bottom: 24px;
  }

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

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

  .contact-row {
    grid-template-columns: 80px 1fr auto;
    gap: 12px;
  }

  .footer-inner {
    flex-direction: column;
    gap: 8px;
    text-align: center;
  }

  .scroll-hint {
    display: none;
  }
}

@media (max-width: 480px) {
  .skills-grid {
    grid-template-columns: 1fr;
  }

  .hero-cta {
    flex-direction: column;
  }

  .btn {
    justify-content: center;
  }

  .contact-row {
    grid-template-columns: 1fr auto;
  }

  .contact-label {
    display: none;
  }
}

/* ==========================================================================
   Selection & Focus
   ========================================================================== */

::selection {
  background: rgba(0, 200, 240, 0.2);
  color: var(--text);
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 2px;
}

/* ==========================================================================
   Scrollbar
   ========================================================================== */

::-webkit-scrollbar {
  width: 6px;
}

::-webkit-scrollbar-track {
  background: var(--bg);
}

::-webkit-scrollbar-thumb {
  background: var(--border-light);
  border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--text-dim);
}

/* ==========================================================================
   Light Mode
   ========================================================================== */

[data-theme="light"] {
  --bg: #f0f4f9;
  --bg-surface: #e6ecf4;
  --bg-elevated: #dce4ef;
  --border: #c4d0e3;
  --border-light: #aabcd4;
  --text: #0c1422;
  --text-muted: #3a5272;
  --text-dim: #6a88a8;
  --accent: #0088b8;
  --accent-dim: rgba(0, 136, 184, 0.1);
  --accent-glow: 0 0 24px rgba(0, 136, 184, 0.15);
}

[data-theme="light"] #nav.scrolled {
  background: rgba(240, 244, 249, 0.88);
}

[data-theme="light"] .name-outline {
  -webkit-text-stroke: 1.5px rgba(12, 20, 34, 0.18);
  background: linear-gradient(135deg, rgba(0, 136, 184, 0.35), transparent 60%);
  -webkit-background-clip: text;
  background-clip: text;
}

[data-theme="light"] .hero-glow-1 {
  background: radial-gradient(circle, rgba(0, 136, 184, 0.07) 0%, transparent 65%);
}

[data-theme="light"] .hero-glow-2 {
  background: radial-gradient(circle, rgba(16, 185, 129, 0.05) 0%, transparent 65%);
}

[data-theme="light"] .tech-tags span {
  border-color: rgba(0, 136, 184, 0.2);
}

[data-theme="light"] .cert-provider {
  border-color: rgba(0, 136, 184, 0.2);
}

/* Smooth theme transition */
body, #nav, .project-card, .skill-group, .certs-row, .cert-item, .contact-row, .exp-item, .edu-item, footer {
  transition: background-color 0.25s ease, border-color 0.25s ease, color 0.25s ease;
}