/* ===== EMBEDDED GEIST FONTS ===== */

@font-face {
  font-family: 'Geist Sans';
  src: url('geist-font/Geist/webfonts/Geist[wght].woff2') format('woff2');
  font-weight: 100 900;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: 'Geist Mono';
  src: url('geist-font/GeistMono/webfonts/GeistMono[wght].woff2') format('woff2');
  font-weight: 100 900;
  font-style: normal;
  font-display: swap;
}

/* ===== CSS VARIABLES (Geist Design Tokens) ===== */

/* ===== LIGHT THEME (default) ===== */
:root {
  --font-sans: "Geist Sans", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-mono: "Geist Mono", "SF Mono", "Fira Code", monospace;

  --bg-100: #ffffff;
  --bg-200: #fafafa;
  --gray-100: #f2f2f2;
  --gray-200: #ebebeb;
  --gray-300: #e6e6e6;
  --gray-400: #eaeaea;
  --gray-500: #c9c9c9;
  --gray-600: #a8a8a8;
  --gray-700: #8f8f8f;
  --gray-800: #7d7d7d;
  --gray-900: #4d4d4d;
  --gray-1000: #171717;
  --gray-alpha-100: rgba(0,0,0,0.05);
  --gray-alpha-200: rgba(0,0,0,0.08);
  --gray-alpha-300: rgba(0,0,0,0.10);
  --gray-alpha-400: rgba(0,0,0,0.08);
  --gray-alpha-500: rgba(0,0,0,0.21);
  --gray-alpha-600: rgba(0,0,0,0.24);
  --gray-alpha-700: rgba(0,0,0,0.44);
  --gray-alpha-800: rgba(0,0,0,0.51);
  --gray-alpha-900: rgba(0,0,0,0.70);
  --gray-alpha-1000: rgba(0,0,0,0.91);
  --blue-100: #f0f7ff;
  --blue-200: #e9f4ff;
  --blue-300: #dfefff;
  --blue-400: #cae7ff;
  --blue-500: #94ccff;
  --blue-600: #48aeff;
  --blue-700: #006bff;
  --blue-800: #0059ec;
  --blue-900: #005ff2;
  --blue-1000: #002359;
  --red-700: #fc0035;
  --green-700: #28a948;
  --amber-700: #ffae00;
  --shadow-raised: 0 2px 2px rgba(0,0,0,0.04);
  --shadow-popover: 0 1px 1px rgba(0,0,0,0.02), 0 4px 8px -4px rgba(0,0,0,0.04), 0 16px 24px -8px rgba(0,0,0,0.06);
  --shadow-modal: 0 1px 1px rgba(0,0,0,0.02), 0 8px 16px -4px rgba(0,0,0,0.04), 0 24px 32px -8px rgba(0,0,0,0.06);
}

/* ===== DARK THEME ===== */
[data-theme="dark"] {
  --bg-100: #0a0a0a;
  --bg-200: #111111;
  --gray-100: #1a1a1a;
  --gray-200: #1f1f1f;
  --gray-300: #292929;
  --gray-400: #2e2e2e;
  --gray-500: #454545;
  --gray-600: #6a6a6a;
  --gray-700: #8a8a8a;
  --gray-800: #a0a0a0;
  --gray-900: #c9c9c9;
  --gray-1000: #ededed;
  --gray-alpha-100: rgba(255,255,255,0.05);
  --gray-alpha-200: rgba(255,255,255,0.08);
  --gray-alpha-300: rgba(255,255,255,0.10);
  --gray-alpha-400: rgba(255,255,255,0.08);
  --gray-alpha-500: rgba(255,255,255,0.21);
  --gray-alpha-600: rgba(255,255,255,0.24);
  --gray-alpha-700: rgba(255,255,255,0.44);
  --gray-alpha-800: rgba(255,255,255,0.51);
  --gray-alpha-900: rgba(255,255,255,0.70);
  --gray-alpha-1000: rgba(255,255,255,0.91);
  --blue-100: #0a2540;
  --blue-200: #0f2d4d;
  --blue-300: #153a5c;
  --blue-400: #1a4a6e;
  --blue-500: #2563a8;
  --blue-600: #3b82c4;
  --blue-700: #60a5fa;
  --blue-800: #7eb8fc;
  --blue-900: #93c5fd;
  --blue-1000: #dbeafe;
  --red-700: #f87171;
  --green-700: #4ade80;
  --amber-700: #fbbf24;
  --shadow-raised: 0 2px 2px rgba(0,0,0,0.20);
  --shadow-popover: 0 1px 1px rgba(0,0,0,0.15), 0 4px 8px -4px rgba(0,0,0,0.25), 0 16px 24px -8px rgba(0,0,0,0.35);
  --shadow-modal: 0 1px 1px rgba(0,0,0,0.15), 0 8px 16px -4px rgba(0,0,0,0.25), 0 24px 32px -8px rgba(0,0,0,0.35);
}

/* ===== RESET & BASE ===== */
* { margin: 0; padding: 0; box-sizing: border-box; }
html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-padding-top: 88px;
}
body {
  font-family: var(--font-sans);
  background: var(--bg-100);
  color: var(--gray-1000);
  line-height: 1.6;
  letter-spacing: -0.01em;
  word-spacing: -0.02em;
  transition: background 200ms ease, color 200ms ease;
}

/* ===== THEME TOGGLE ===== */
.theme-toggle {
  background: none;
  border: 1px solid var(--gray-alpha-400);
  border-radius: 9999px;
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: var(--gray-800);
  transition: all 150ms cubic-bezier(0.175, 0.885, 0.32, 1.1);
  padding: 0;
}
.theme-toggle:hover {
  background: var(--gray-alpha-100);
  color: var(--gray-1000);
  border-color: var(--gray-alpha-600);
}
.theme-toggle svg {
  width: 18px;
  height: 18px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.5;
  stroke-linecap: round;
  stroke-linejoin: round;
}

/* ===== NAVBAR ===== */
.navbar {
  position: sticky;
  top: 0;
  background: var(--bg-100);
  backdrop-filter: blur(16px) saturate(180%);
  -webkit-backdrop-filter: blur(16px) saturate(180%);
  border-bottom: 1px solid var(--gray-alpha-200);
  z-index: 1000;
  transition: background 200ms ease, border-color 200ms ease;
}
.nav-container {
  max-width: 1200px;
  margin: auto;
  padding: 16px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.logo a {
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 600;
  line-height: 20px;
  letter-spacing: -0.28px;
  color: var(--gray-1000);
  text-decoration: none;
}
.nav-right {
  display: flex;
  align-items: center;
  gap: 24px;
}
.nav-links {
  display: flex;
  gap: 24px;
}
.nav-links a {
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 400;
  line-height: 20px;
  letter-spacing: -0.01em;
  color: var(--gray-800);
  text-decoration: none;
  padding: 4px 0;
  position: relative;
  transition: color 150ms cubic-bezier(0.175, 0.885, 0.32, 1.1);
}
.nav-links a::after {
  content: "";
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 1.5px;
  background: var(--gray-1000);
  transition: width 200ms cubic-bezier(0.175, 0.885, 0.32, 1.1);
}
.nav-links a:hover { color: var(--gray-1000); }
.nav-links a:hover::after,
.nav-links a.active::after { width: 100%; }
.nav-links a.active { color: var(--gray-1000); font-weight: 500; }

/* ===== LAYOUT ===== */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== HERO ===== */
header.container {
  padding-top: 96px;
  padding-bottom: 64px;
}
header h1 {
  font-family: var(--font-sans);
  font-size: 72px;
  font-weight: 600;
  line-height: 72px;
  letter-spacing: -4.32px;
  color: var(--gray-1000);
  margin-bottom: 16px;
}
header .subtitle {
  font-family: var(--font-sans);
  font-size: 20px;
  font-weight: 400;
  line-height: 32px;
  letter-spacing: -0.02em;
  color: var(--gray-700);
  margin-bottom: 24px;
}
header .links {
  display: flex;
  gap: 16px;
  margin-top: 24px;
}
header .links a {
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 500;
  line-height: 20px;
  color: var(--gray-1000);
  text-decoration: none;
  padding: 10px 14px;
  border: 1px solid var(--gray-alpha-400);
  border-radius: 6px;
  background: var(--bg-100);
  transition: all 150ms cubic-bezier(0.175, 0.885, 0.32, 1.1);
}
header .links a:hover {
  background: var(--gray-100);
  border-color: var(--gray-alpha-600);
}

/* ===== SECTIONS ===== */
section.container {
  padding-top: 64px;
  padding-bottom: 64px;
}
section.container + section.container {
  padding-top: 0;
}
h2 {
  font-family: var(--font-sans);
  font-size: 40px;
  font-weight: 600;
  line-height: 48px;
  letter-spacing: -2.4px;
  color: var(--gray-1000);
  margin-bottom: 16px;
}
.section-subtitle {
  font-family: var(--font-sans);
  font-size: 18px;
  font-weight: 400;
  line-height: 28px;
  letter-spacing: -0.01em;
  color: var(--gray-700);
  margin-bottom: 32px;
}

/* ===== ABOUT ===== */
section p {
  font-family: var(--font-sans);
  font-size: 16px;
  font-weight: 400;
  line-height: 24px;
  letter-spacing: -0.01em;
  color: var(--gray-800);
  max-width: 720px;
}
section p + p { margin-top: 16px; }

/* ===== CASE FILES / CATEGORY GRID ===== */
.category-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}
.category-card {
  background: var(--bg-100);
  padding: 32px;
  border-radius: 12px;
  border: 1px solid var(--gray-alpha-300);
  text-decoration: none;
  color: inherit;
  transition: all 200ms cubic-bezier(0.175, 0.885, 0.32, 1.1);
  position: relative;
  overflow: hidden;
}
.category-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--gray-1000);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 200ms cubic-bezier(0.175, 0.885, 0.32, 1.1);
}
.category-card:hover {
  transform: translateY(-2px);
  border-color: var(--gray-alpha-500);
  box-shadow: var(--shadow-popover);
}
.category-card:hover::before { transform: scaleX(1); }
.category-card h3 {
  font-family: var(--font-sans);
  font-size: 24px;
  font-weight: 600;
  line-height: 32px;
  letter-spacing: -0.96px;
  color: var(--gray-1000);
  margin-bottom: 12px;
}
.category-card p {
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 400;
  line-height: 20px;
  letter-spacing: -0.01em;
  color: var(--gray-700);
  margin-bottom: 24px;
}
.category-card span {
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 500;
  line-height: 20px;
  color: var(--gray-1000);
  display: inline-flex;
  align-items: center;
  gap: 4px;
  transition: gap 150ms cubic-bezier(0.175, 0.885, 0.32, 1.1);
}
.category-card:hover span { gap: 12px; }

/* ===== EXPERIENCE ===== */
.experience-list {
  display: flex;
  flex-direction: column;
  gap: 20px;
  margin-top: 24px;
  position: relative;
}
.experience-list::before {
  content: "";
  position: absolute;
  left: 9px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: var(--gray-alpha-300);
}
.experience-item {
  display: flex;
  gap: 16px;
  position: relative;
}
.exp-dot {
  width: 20px;
  height: 20px;
  border-radius: 9999px;
  background: var(--bg-100);
  border: 2px solid var(--gray-1000);
  margin-top: 8px;
  flex-shrink: 0;
  position: relative;
  z-index: 1;
  box-shadow: 0 0 0 4px var(--bg-100);
}
.exp-card {
  flex: 1;
  padding: 20px 24px;
  border-radius: 12px;
  border: 1px solid var(--gray-alpha-200);
  background: var(--bg-100);
  transition: all 150ms cubic-bezier(0.175, 0.885, 0.32, 1.1);
}
.exp-card:hover {
  border-color: var(--gray-alpha-400);
  box-shadow: var(--shadow-popover);
  transform: translateY(-2px);
}
.exp-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 16px;
  margin-bottom: 10px;
}
.exp-header h3 {
  font-family: var(--font-sans);
  font-size: 20px;
  font-weight: 600;
  line-height: 28px;
  letter-spacing: -0.8px;
  color: var(--gray-1000);
  margin-bottom: 6px;
}
.exp-org {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  line-height: 16px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--gray-600);
}
.exp-date {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  line-height: 16px;
  color: var(--gray-700);
  white-space: nowrap;
}
.exp-card p {
  font-family: var(--font-sans);
  font-size: 15px;
  font-weight: 400;
  line-height: 24px;
  letter-spacing: -0.01em;
  color: var(--gray-800);
  max-width: none;
}

/* ===== CERTIFICATIONS ===== */
.cert-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
  margin-top: 24px;
}
.cert-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 16px 24px;
  border-radius: 6px;
  border: 1px solid var(--gray-alpha-200);
  background: var(--bg-100);
  transition: all 150ms cubic-bezier(0.175, 0.885, 0.32, 1.1);
}
.cert-item:hover {
  background: var(--bg-200);
  border-color: var(--gray-alpha-400);
}
.cert-dot {
  width: 8px;
  height: 8px;
  border-radius: 9999px;
  background: var(--green-700);
  flex-shrink: 0;
}
.cert-dot-ongoing { background: var(--amber-700); }
.cert-name {
  font-family: var(--font-sans);
  font-size: 16px;
  font-weight: 400;
  line-height: 24px;
  letter-spacing: -0.01em;
  color: var(--gray-900);
}

/* ===== SKILLS ===== */
.skills {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
  margin-top: 24px;
}
.skill-group {
  padding: 24px;
  border-radius: 6px;
  border: 1px solid var(--gray-alpha-200);
  background: var(--bg-100);
  transition: all 150ms cubic-bezier(0.175, 0.885, 0.32, 1.1);
}
.skill-group:hover {
  background: var(--gray-alpha-200);
  border-color: var(--gray-alpha-400);
}
.skill-group h4 {
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 600;
  line-height: 20px;
  letter-spacing: -0.28px;
  color: var(--gray-1000);
  margin-bottom: 8px;
  text-transform: uppercase;
}
.skill-group p {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 400;
  line-height: 20px;
  color: var(--gray-700);
  max-width: none;
}
.chip-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.chip-list span {
  display: inline-flex;
  align-items: center;
  padding: 8px 12px;
  border-radius: 999px;
  background: var(--gray-alpha-200);
  border: 1px solid var(--gray-alpha-200);
  color: var(--gray-900);
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 16px;
  letter-spacing: 0.01em;
}

/* ===== FOOTER ===== */
footer.container {
  padding-top: 40px;
  padding-bottom: 40px;
  border-top: 1px solid var(--gray-alpha-200);
  margin-top: 64px;
}
footer p {
  font-family: var(--font-sans);
  font-size: 13px;
  font-weight: 400;
  line-height: 18px;
  letter-spacing: -0.01em;
  color: var(--gray-600);
  text-align: center;
}

/* ===== PROJECTS PAGE (cybersecurity.html) ===== */
.back-link {
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 500;
  line-height: 20px;
  color: var(--gray-700);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 24px;
  transition: color 150ms cubic-bezier(0.175, 0.885, 0.32, 1.1);
}
.back-link:hover { color: var(--gray-1000); }

.page-header {
  padding-top: 40px;
  padding-bottom: 24px;
}
.page-header h1 {
  font-family: var(--font-sans);
  font-size: 48px;
  font-weight: 600;
  line-height: 56px;
  letter-spacing: -2.88px;
  color: var(--gray-1000);
  margin-bottom: 12px;
}
.page-header .section-subtitle {
  margin-bottom: 0;
}

.project-list {
  display: grid;
  gap: 24px;
  margin-top: 32px;
  margin-bottom: 96px;
}
.project-card {
  background: var(--bg-100);
  padding: 32px;
  border-radius: 12px;
  border: 1px solid var(--gray-alpha-200);
  transition: all 200ms cubic-bezier(0.175, 0.885, 0.32, 1.1);
  position: relative;
  overflow: hidden;
}
.project-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 3px;
  height: 100%;
  background: var(--gray-1000);
  transform: scaleY(0);
  transform-origin: top;
  transition: transform 200ms cubic-bezier(0.175, 0.885, 0.32, 1.1);
}
.project-card:hover {
  border-color: var(--gray-alpha-400);
  box-shadow: var(--shadow-popover);
  transform: translateY(-1px);
}
.project-card:hover::before { transform: scaleY(1); }

.case-label {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  line-height: 16px;
  letter-spacing: 0.08em;
  color: var(--gray-500);
  text-transform: uppercase;
  margin-bottom: 12px;
}
.project-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 12px;
}
.recent-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 6px 10px;
  border-radius: 999px;
  background: rgba(72, 174, 255, 0.12);
  border: 1px solid rgba(72, 174, 255, 0.35);
  color: var(--blue-700);
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  white-space: nowrap;
}
.project-card h3 {
  font-family: var(--font-sans);
  font-size: 24px;
  font-weight: 600;
  line-height: 32px;
  letter-spacing: -0.96px;
  color: var(--gray-1000);
  margin-bottom: 0;
}
.project-card p {
  font-family: var(--font-sans);
  font-size: 16px;
  font-weight: 400;
  line-height: 24px;
  letter-spacing: -0.01em;
  color: var(--gray-700);
  max-width: 640px;
  margin-bottom: 16px;
}
.tags {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 400;
  line-height: 16px;
  color: var(--gray-600);
  margin-bottom: 24px;
}
.project-card > a {
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 500;
  line-height: 20px;
  color: var(--gray-1000);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 10px 14px;
  border: 1px solid var(--gray-alpha-400);
  border-radius: 6px;
  background: var(--bg-100);
  transition: all 150ms cubic-bezier(0.175, 0.885, 0.32, 1.1);
}
.project-card > a:hover {
  background: var(--gray-100);
  border-color: var(--gray-alpha-600);
  gap: 12px;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
  header h1 { font-size: 40px; line-height: 48px; letter-spacing: -2.4px; }
  header .subtitle { font-size: 18px; line-height: 28px; }
  h2 { font-size: 32px; line-height: 40px; letter-spacing: -1.28px; }
  .category-grid { grid-template-columns: 1fr; }
  .skills { grid-template-columns: 1fr; }
  .nav-links { gap: 16px; }
  .nav-links a { font-size: 13px; }
  .page-header h1 { font-size: 32px; line-height: 40px; letter-spacing: -1.28px; }
}

@media (max-width: 480px) {
  header h1 { font-size: 32px; line-height: 40px; letter-spacing: -1.28px; }
  header .links { flex-wrap: wrap; }
  .nav-container { padding: 12px 16px; }
  .container { padding: 0 16px; }
  .nav-right { gap: 12px; }
  .nav-links { gap: 12px; }
  .exp-header { flex-direction: column; }
  .exp-date { white-space: normal; }
}

/* ===== SCROLLBAR ===== */
::-webkit-scrollbar { width: 8px; }
::-webkit-scrollbar-track { background: var(--bg-100); }
::-webkit-scrollbar-thumb { background: var(--gray-300); border-radius: 9999px; }
::-webkit-scrollbar-thumb:hover { background: var(--gray-500); }

/* ===== SELECTION ===== */
::selection { background: var(--blue-200); color: var(--blue-1000); }