/* ==========================================================================
   Duy Hoàng Portfolio — Design System
   ========================================================================== */

/* --- Theme Variables --- */
:root {
  --bg: #070910;
  --card: #101622;
  --text: #f7f8fb;
  --muted: #aab4c4;
  --dim: #707c8f;
  --line: rgba(255,255,255,.09);
  --purple: #8d73ff;
  --mint: #66dec4;
  --max: 1180px;
  --nav-bg: rgba(7,9,16,.84);
  --body-grid-color: rgba(255,255,255,.018);
  --glass-from: rgba(255,255,255,.045);
  --glass-to: rgba(255,255,255,.017);
  --btn-bg: rgba(255,255,255,.035);
  --btn-hover-border: rgba(255,255,255,.2);
  --menu-bg: rgba(255,255,255,.035);
  --menu-hover: rgba(255,255,255,.1);
  --drawer-bg: rgba(9,12,20,.98);
  --terminal-bg: rgba(10,14,22,.88);
  --gradient-text: linear-gradient(100deg,#fff 15%,#b19fff 55%,#75ddc8 90%);
  --glass-bg: rgba(9,12,20,.85);
  color-scheme: dark;
}

/* Light mode overrides */
[data-theme="light"] {
  --bg: #f5f6fa;
  --card: #ffffff;
  --text: #1a1d26;
  --muted: #5a6478;
  --dim: #8892a4;
  --line: rgba(0,0,0,.09);
  --purple: #6d4fe8;
  --mint: #1db99a;
  --nav-bg: rgba(245,246,250,.88);
  --body-grid-color: rgba(0,0,0,.035);
  --glass-from: rgba(0,0,0,.025);
  --glass-to: rgba(0,0,0,.008);
  --btn-bg: rgba(0,0,0,.04);
  --btn-hover-border: rgba(0,0,0,.18);
  --menu-bg: rgba(0,0,0,.04);
  --menu-hover: rgba(0,0,0,.08);
  --drawer-bg: rgba(245,246,250,.98);
  --terminal-bg: rgba(240,242,248,.95);
  --gradient-text: linear-gradient(100deg,#1a1d26 15%,#6d4fe8 55%,#1db99a 90%);
  --glass-bg: rgba(245,246,250,.95);
  color-scheme: light;
}

/* --- Reset & Base --- */
* { box-sizing: border-box }
html { scroll-behavior: smooth }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.7 Inter, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  transition: background .35s ease, color .35s ease;
}
body.drawer-open { overflow: hidden }
body:before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  background:
    radial-gradient(circle at 82% 5%, rgba(141,115,255,.16), transparent 28rem),
    radial-gradient(circle at 0 55%, rgba(102,222,196,.055), transparent 25rem),
    linear-gradient(var(--body-grid-color) 1px, transparent 1px),
    linear-gradient(90deg, var(--body-grid-color) 1px, transparent 1px);
  background-size: auto, auto, 48px 48px, 48px 48px;
  transition: background .35s ease;
}
[data-theme="light"] body:before {
  background:
    radial-gradient(circle at 82% 5%, rgba(109,79,232,.08), transparent 28rem),
    radial-gradient(circle at 0 55%, rgba(29,185,154,.04), transparent 25rem),
    linear-gradient(var(--body-grid-color) 1px, transparent 1px),
    linear-gradient(90deg, var(--body-grid-color) 1px, transparent 1px);
  background-size: auto, auto, 48px 48px, 48px 48px;
}
a { color: var(--text); text-decoration: none; transition: color .2s }
.container { width: min(var(--max), calc(100% - 42px)); margin: auto }

/* --- Navigation --- */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  border-bottom: 1px solid var(--line);
  background: var(--nav-bg);
  backdrop-filter: blur(18px);
  transition: background .35s ease, border-color .35s ease;
}
.nav-inner {
  height: 76px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}
.nav-links {
  display: flex;
  align-items: center;
  gap: 24px;
}
.nav-links a {
  font-family: 'Inter', sans-serif;
  font-weight: 700;
  font-size: 15px;
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.2s ease;
}
.nav-links a:hover, .nav-links a.active {
  color: var(--text);
}
@media (max-width: 768px) {
  .d-none-md {
    display: none !important;
  }
}
.brand {
  display: flex;
  align-items: center;
  gap: 11px;
  font-weight: 850;
  white-space: nowrap;
}
.nav-avatar {
  width: 40px; height: 40px;
  border-radius: 11px;
  overflow: hidden;
  display: block;
  flex: 0 0 40px;
  border: 1px solid rgba(255,255,255,.14);
  background: #fff;
  box-shadow: 0 6px 20px rgba(0,0,0,.2);
}
[data-theme="light"] .nav-avatar {
  border-color: rgba(0,0,0,.1);
  box-shadow: 0 4px 14px rgba(0,0,0,.08);
}
.nav-avatar img {
  width: 100%; height: 100%;
  display: block;
  object-fit: contain;
  object-position: center;
  background: #fff;
}
.brand small {
  display: block;
  color: var(--dim);
  font-size: 9px;
  letter-spacing: .12em;
  text-transform: uppercase;
}

/* Menu */
.menu {
  display: flex;
  gap: 3px;
  padding: 5px;
  border: 1px solid var(--line);
  border-radius: 13px;
  background: var(--menu-bg);
  transition: background .35s ease, border-color .35s ease;
}
.menu a {
  color: var(--muted);
  font-size: 12px;
  padding: 8px 10px;
  border-radius: 8px;
  transition: color .2s, background .2s;
}
.menu a:hover, .menu a.active {
  color: var(--text);
  background: var(--menu-hover);
}

/* Status */
.status {
  display: flex;
  align-items: center;
  gap: 7px;
  color: #a9eadb;
  font-size: 11px;
  white-space: nowrap;
}
[data-theme="light"] .status { color: #0f8f6e }
.dot {
  width: 7px; height: 7px;
  border-radius: 50%;
  background: var(--mint);
  box-shadow: 0 0 13px var(--mint);
  animation: pulse-dot 2s infinite;
}
@keyframes pulse-dot {
  0%, 100% { opacity: 1 }
  50% { opacity: .5 }
}

/* Custom Language Select */
.custom-lang-select {
  position: relative;
  display: inline-block;
  user-select: none;
  font-family: Inter, system-ui, sans-serif;
  outline: none;
}
.custom-lang-select .cls-trigger {
  display: flex;
  align-items: center;
  gap: 6px;
  cursor: pointer;
  background: var(--btn-bg);
  border: 1px solid var(--line);
  color: var(--text);
  border-radius: 10px;
  padding: 8px 10px;
  font-size: 11px;
  font-weight: 700;
  transition: background-color .35s ease, border-color .35s ease, color .35s ease;
}
.custom-lang-select:focus .cls-trigger, .custom-lang-select.open .cls-trigger {
  border-color: var(--dim);
}
.custom-lang-select .cls-flag {
  font-size: 13px;
  line-height: 1;
}
.custom-lang-select .cls-options {
  position: absolute;
  top: calc(100% + 4px);
  left: 0;
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: 10px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.15);
  list-style: none;
  padding: 6px;
  margin: 0;
  min-width: 110px;
  z-index: 1000;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-5px);
  transition: all 0.2s ease;
}
.drawer-lang .custom-lang-select .cls-options {
  top: auto;
  bottom: calc(100% + 4px);
}
.custom-lang-select.open .cls-options {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}
.custom-lang-select .cls-options li {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  cursor: pointer;
  border-radius: 6px;
  font-size: 11px;
  font-weight: 700;
  color: var(--dim);
  transition: background 0.2s, color 0.2s;
}
.custom-lang-select .cls-options li:hover, .custom-lang-select .cls-options li.active {
  background: var(--btn-bg);
  color: var(--text);
}

/* Nav Controls */
.nav-controls { display: flex; align-items: center; gap: 9px }

/* Theme Toggle Button */
.theme-toggle {
  width: 42px; height: 42px;
  border: 1px solid var(--line);
  border-radius: 11px;
  background: var(--btn-bg);
  color: var(--text);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  transition: background .2s, border-color .2s, transform .2s;
  padding: 0;
  line-height: 1;
}
.theme-toggle:hover {
  border-color: var(--btn-hover-border);
  transform: rotate(15deg);
}
.theme-toggle .icon-sun { display: none }
.theme-toggle .icon-moon { display: inline }
[data-theme="light"] .theme-toggle .icon-sun { display: inline }
[data-theme="light"] .theme-toggle .icon-moon { display: none }

/* Menu Toggle (Hamburger) */
.menu-toggle {
  display: none;
  width: 42px; height: 42px;
  border: 1px solid var(--line);
  border-radius: 11px;
  background: var(--btn-bg);
  color: var(--text);
  cursor: pointer;
  align-items: center;
  justify-content: center;
  font-size: 20px;
}
.menu-toggle span,
.menu-toggle span:before,
.menu-toggle span:after {
  display: block;
  width: 18px; height: 2px;
  background: var(--text);
  border-radius: 2px;
  content: "";
  transition: .25s;
}
.menu-toggle span:before { transform: translateY(-6px) }
.menu-toggle span:after { transform: translateY(4px) }

/* Mobile Drawer */
.drawer-overlay {
  position: fixed; inset: 0;
  background: rgba(0,0,0,.58);
  backdrop-filter: blur(3px);
  z-index: 190;
  opacity: 0; visibility: hidden;
  transition: opacity .25s, visibility .25s;
}
.mobile-drawer {
  position: fixed;
  top: 0; right: 0; bottom: 0;
  width: min(86vw, 360px);
  z-index: 200;
  background: var(--drawer-bg);
  border-left: 1px solid var(--line);
  box-shadow: -25px 0 70px rgba(0,0,0,.5);
  transform: translateX(100%);
  transition: transform .3s ease, background .35s ease;
  padding: 20px;
  display: flex;
  flex-direction: column;
}
.mobile-drawer.open { transform: translateX(0) }

/* Left Sidebar Menu */
.left-sidebar-trigger {
  position: fixed;
  top: 50%;
  left: 0;
  transform: translateY(-50%);
  background: var(--btn-bg);
  border: 1px solid var(--line);
  border-left: 0;
  border-radius: 0 12px 12px 0;
  padding: 16px 12px;
  cursor: pointer;
  z-index: 900;
  box-shadow: 2px 0 10px rgba(0,0,0,0.1);
  transition: background 0.3s, padding 0.3s;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text);
}
.left-sidebar-trigger:hover {
  background: var(--btn-hover-bg);
  padding-left: 18px;
}
.left-sidebar {
  position: fixed;
  top: 0;
  left: 0;
  width: 320px;
  height: 100vh;
  background: var(--glass-bg);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-right: 1px solid var(--line);
  z-index: 1001;
  transform: translateX(-100%);
  transition: transform 0.4s cubic-bezier(0.16, 1, 0.3, 1);
  display: flex;
  flex-direction: column;
  padding: 40px;
}
.left-sidebar.open { transform: translateX(0); }
.left-sidebar-close {
  position: absolute;
  top: 24px;
  right: 24px;
  background: none;
  border: none;
  color: var(--text);
  font-size: 24px;
  cursor: pointer;
  opacity: 0.7;
  transition: opacity 0.2s, transform 0.2s;
}
.left-sidebar-close:hover {
  opacity: 1;
  transform: scale(1.1);
}
.left-sidebar-profile {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  margin-bottom: auto;
  margin-top: 20px;
}
.lsp-avatar {
  width: 76px;
  height: 76px;
  border-radius: 50%;
  object-fit: cover;
  margin-bottom: 12px;
  border: 2px solid var(--line);
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}
.lsp-name {
  font-size: 19px;
  font-weight: 800;
  color: var(--text);
  margin-bottom: 10px;
}
.lsp-contact {
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.lsp-contact a {
  color: var(--muted);
  font-size: 13.5px;
  text-decoration: none;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  transition: color 0.3s;
}
.lsp-contact a:hover {
  color: var(--purple);
}
.left-sidebar-nav {
  display: flex;
  flex-direction: column;
  gap: 24px;
  text-align: center;
  margin-bottom: auto;
}
.left-sidebar-nav a {
  font-size: 20px;
  font-weight: 800;
  color: var(--text);
  text-decoration: none;
  opacity: 0.8;
  text-transform: uppercase;
  letter-spacing: 1px;
  transition: color 0.3s, opacity 0.3s, transform 0.3s;
}
.left-sidebar-nav a:hover {
  opacity: 1;
  color: var(--purple);
  transform: translateX(6px);
}
[data-theme="light"] .left-sidebar-nav a:hover { color: #6d4fe8; }

.left-sidebar-social {
  position: absolute;
  bottom: 40px;
  left: 0;
  width: 100%;
  display: flex;
  justify-content: center;
  gap: 16px;
}
.left-sidebar-social a {
  color: var(--text);
  font-size: 22px;
  opacity: 0.6;
  transition: opacity 0.3s, transform 0.3s, color 0.3s;
}
.left-sidebar-social a:hover {
  opacity: 1;
  transform: translateY(-3px);
  color: var(--purple);
}
[data-theme="light"] .left-sidebar-social a:hover { color: #6d4fe8; }

.drawer-overlay.open { opacity: 1; visibility: visible }
.drawer-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--line);
}
.drawer-title { font-weight: 850 }
.drawer-close {
  width: 40px; height: 40px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--btn-bg);
  color: var(--text);
  font-size: 22px;
  cursor: pointer;
}
.drawer-links { display: grid; gap: 7px; padding-top: 20px }
.drawer-links a {
  padding: 14px 15px;
  border: 1px solid transparent;
  border-radius: 12px;
  color: var(--muted);
  font-weight: 750;
  transition: background .2s, border-color .2s, color .2s;
}
.drawer-links a:hover, .drawer-links a.active {
  background: var(--menu-hover);
  border-color: var(--line);
  color: var(--text);
}
.drawer-lang {
  margin-top: auto;
  padding-top: 20px;
  border-top: 1px solid var(--line);
}
.drawer-lang label {
  display: block;
  color: var(--dim);
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: .12em;
  margin-bottom: 8px;
}
.drawer-lang .custom-lang-select { width: 100%; }
.drawer-lang .custom-lang-select .cls-trigger { height: 44px; }

/* --- Sections --- */
section {
  padding: 100px 0;
  border-bottom: 1px solid rgba(255,255,255,.055);
}
[data-theme="light"] section { border-bottom-color: rgba(0,0,0,.06) }

/* Hero */
.hero {
  min-height: calc(100vh - 76px);
  display: grid;
  grid-template-columns: 1.18fr .82fr;
  align-items: center;
  gap: 70px;
}
.eyebrow {
  display: inline-flex;
  padding: 7px 11px;
  border-radius: 999px;
  border: 1px solid rgba(141,115,255,.27);
  background: rgba(141,115,255,.07);
  color: #b8abff;
  font-size: 10px;
  font-weight: 850;
  letter-spacing: .14em;
  text-transform: uppercase;
}
[data-theme="light"] .eyebrow {
  color: #6d4fe8;
  border-color: rgba(109,79,232,.25);
  background: rgba(109,79,232,.06);
}

/* Typography */
h1 { font-size: clamp(50px,7vw,88px); line-height: .97; letter-spacing: -.075em; margin: 22px 0 }
h2 { font-size: clamp(37px,5vw,60px); line-height: 1; letter-spacing: -.06em; margin: 0 0 18px }
h3 { letter-spacing: -.025em }
.gradient {
  background: var(--gradient-text);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.lead {
  font-size: 19px;
  line-height: 1.85;
  color: var(--muted);
  max-width: 760px;
}

/* Buttons & Pills */
.actions, .pills { display: flex; flex-wrap: wrap; gap: 8px }
.actions { margin-top: 28px }
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--line);
  border-radius: 11px;
  padding: 12px 16px;
  font-size: 12px;
  font-weight: 800;
  background: var(--btn-bg);
  transition: border-color .2s, background .2s, transform .15s;
}
.btn:hover { border-color: var(--btn-hover-border); transform: translateY(-1px) }
.primary { border: 0; background: linear-gradient(135deg, var(--purple), #705ad4); color: #fff }
[data-theme="light"] .primary { background: linear-gradient(135deg, #6d4fe8, #5038b8); color: #fff }
.pill {
  padding: 6px 9px;
  border-radius: 8px;
  border: 1px solid rgba(255,255,255,.08);
  background: rgba(255,255,255,.035);
  color: #c3ccd9;
  font-size: 11px;
  line-height: 1.3;
  transition: background .35s, border-color .35s, color .35s;
}
[data-theme="light"] .pill {
  border-color: rgba(0,0,0,.08);
  background: rgba(0,0,0,.035);
  color: #4a5568;
}
.pill.main { color: #c8beff; border-color: rgba(141,115,255,.25); background: rgba(141,115,255,.08) }
[data-theme="light"] .pill.main { color: #5b3dcc; border-color: rgba(109,79,232,.2); background: rgba(109,79,232,.06) }
.pill.ai { color: #a2ecdc; border-color: rgba(102,222,196,.23); background: rgba(102,222,196,.055) }
[data-theme="light"] .pill.ai { color: #0d8068; border-color: rgba(29,185,154,.2); background: rgba(29,185,154,.06) }

/* Profile */
.profile-wrap { display: flex; flex-direction: column; align-items: center; gap: 16px }
.profile-photo {
  width: 330px; height: 440px;
  object-fit: contain;
  object-position: center;
  border-radius: 28px;
  border: 1px solid rgba(255,255,255,.13);
  background: #fff;
  box-shadow: 0 30px 100px rgba(0,0,0,.42), 0 0 0 8px rgba(255,255,255,.025);
  transition: box-shadow .35s, border-color .35s;
}
[data-theme="light"] .profile-photo {
  border-color: rgba(0,0,0,.08);
  box-shadow: 0 20px 60px rgba(0,0,0,.1), 0 0 0 6px rgba(0,0,0,.02);
}
.profile-caption { text-align: center; color: var(--muted); font-size: 11px; line-height: 1.7 }
.profile-caption strong { display: block; color: var(--text); font-size: 14px }

/* Contact Info (Hero) */
.contact-info { display: flex; justify-content: center; flex-wrap: wrap; gap: 8px; margin: 0 auto 24px }
.contact-info .btn { font-size: 11px }
.contact-meta { display: grid; grid-template-columns: repeat(2,1fr); gap: 8px; max-width: 650px; margin: 0 auto 24px }
.contact-meta .meta {
  padding: 11px 13px;
  border: 1px solid var(--line);
  border-radius: 11px;
  background: var(--btn-bg);
  text-align: left;
}
.contact-meta .meta b { display: block; color: var(--text); font-size: 10px; text-transform: uppercase; letter-spacing: .1em; margin-bottom: 2px }
.contact-meta .meta span { color: var(--muted); font-size: 12px; word-break: break-word }
.contact-meta a { color: var(--muted); transition: color .2s }
.contact-meta a:hover { color: var(--text) }

/* Terminal */
.terminal {
  border: 1px solid var(--line);
  border-radius: 20px;
  overflow: hidden;
  background: var(--terminal-bg);
  box-shadow: 0 30px 100px rgba(0,0,0,.4);
  transform: rotate(1deg);
  transition: background .35s, border-color .35s;
}
.terminal-head { padding: 14px 16px; border-bottom: 1px solid var(--line); display: flex; gap: 6px }
.terminal-head i { width: 8px; height: 8px; border-radius: 50%; background: #3a4351 }
[data-theme="light"] .terminal-head i { background: #c4cad4 }
.terminal-body { padding: 24px; font: 12px/2 ui-monospace, SFMono-Regular, Menlo, monospace; color: var(--muted) }
.purple { color: #b7a7ff }
.green { color: #7de2c6 }
.blue { color: #84baff }
.dim { color: var(--dim) }
[data-theme="light"] .purple { color: #6d4fe8 }
[data-theme="light"] .green { color: #0d8068 }
[data-theme="light"] .blue { color: #2b6cb0 }

/* Section Head */
.section-head { display: flex; align-items: end; justify-content: space-between; gap: 35px; margin-bottom: 32px }
.kicker { color: #a492ff; font-size: 10px; font-weight: 900; letter-spacing: .17em; text-transform: uppercase; margin-bottom: 11px }
[data-theme="light"] .kicker { color: #6d4fe8 }
.intro { max-width: 680px; color: var(--muted); font-size: 15px; line-height: 1.85 }

/* Glass Cards */
.glass {
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 25px;
  background: linear-gradient(145deg, var(--glass-from), var(--glass-to));
  transition: background .35s, border-color .35s;
}

/* About */
.about { display: grid; grid-template-columns: .8fr 1.2fr; gap: 18px }
.about p { color: var(--muted); font-size: 15px; line-height: 1.9 }
.principles { display: grid; gap: 4px }
.principle { display: grid; grid-template-columns: 36px 1fr; gap: 12px; padding: 15px 0; border-bottom: 1px solid var(--line) }
.principle:last-child { border: 0 }
.num { color: #aa9aff; font: 700 11px ui-monospace, monospace }
[data-theme="light"] .num { color: #6d4fe8 }
.principle strong { display: block; font-size: 14px }
.principle span { color: var(--muted); font-size: 12px }

/* Skills */
.skills { display: grid; grid-template-columns: repeat(2,1fr); gap: 13px }
.skill {
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 21px;
  background: var(--btn-bg);
  transition: background .35s, border-color .35s, transform .2s;
}
.skill:hover { transform: translateY(-2px) }
.skill h3 { font-size: 15px; margin: 0 0 14px }

/* Timeline */
.timeline { border-left: 1px solid var(--line); padding-left: 32px; margin-left: 8px; display: grid; gap: 22px }
.role { position: relative; transition: opacity 0.3s; }
.role:hover:before { background: var(--purple); box-shadow: 0 0 16px var(--purple); border-color: var(--purple); }
.role:before {
  content: "";
  position: absolute;
  left: -39px; top: 7px;
  width: 9px; height: 9px;
  border-radius: 50%;
  background: var(--bg);
  border: 2px solid #907aff;
  box-shadow: 0 0 14px rgba(141,115,255,.45);
  transition: background .3s, box-shadow .3s, border-color .3s;
}
.date { font: 700 10px ui-monospace, monospace; color: var(--dim) }
.role h3 { font-size: 18px; margin: 5px 0 2px }
.company { color: #ab9aff; font-size: 11px; font-weight: 850 }
[data-theme="light"] .company { color: #6d4fe8 }
.role p { color: var(--muted); font-size: 13px; line-height: 1.8; margin: 7px 0 0; max-width: 900px }
.role-list { margin: 10px 0 0 18px; padding: 0; list-style: disc; color: var(--muted); font-size: 13px; line-height: 1.8; max-width: 900px; }
.role-list li { margin-bottom: 6px; }

/* Certifications Block */
.cert-block { margin-top: 30px; padding: 20px; background: var(--btn-bg); border-radius: 12px; border: 1px solid var(--line); }
.cert-title { font-weight: 700; color: var(--text); font-size: 16px; margin-bottom: 12px; display: flex; align-items: center; gap: 8px; }
.cert-title i { color: var(--purple); }
.cert-block ul { margin: 0; padding-left: 20px; list-style: square; }
.cert-block li { color: var(--muted); font-size: 14px; margin-bottom: 6px; }
.cert-block li strong { color: var(--text); }

/* Projects */
.projects { display: grid; grid-template-columns: repeat(2,1fr); gap: 13px }
.project {
  min-height: 190px;
  display: flex;
  flex-direction: column;
  border: 1px solid var(--line);
  border-radius: 17px;
  padding: 21px;
  background: linear-gradient(145deg, var(--glass-from), var(--glass-to));
  transition: background .35s, border-color .35s, transform .2s;
}
.project:hover { transform: translateY(-2px) }
.featured {
  grid-column: span 2;
  min-height: 225px;
  background: radial-gradient(circle at 90% 0, rgba(141,115,255,.13), transparent 25rem), var(--btn-bg);
}
[data-theme="light"] .featured {
  background: radial-gradient(circle at 90% 0, rgba(109,79,232,.06), transparent 25rem), var(--btn-bg);
}
.project-top { display: flex; justify-content: space-between; gap: 15px; margin-bottom: 8px }
.project h3 { font-size: 16px; margin: 0 }
.featured h3 { font-size: 23px }
.project-date { font: 10px ui-monospace, monospace; color: var(--dim); white-space: nowrap }
.project p { color: var(--muted); font-size: 13px; line-height: 1.8; margin: 0 }
.project .pills { margin-top: auto; padding-top: 14px }

/* Case Study & AI Grid */
.case-grid, .ai-grid { display: grid; grid-template-columns: .75fr 1.25fr; gap: 14px }
.case h3 { font-size: 25px; line-height: 1.25; margin: 5px 0 10px }
.case p, .ai-card p { color: var(--muted); font-size: 13px; line-height: 1.85 }
.case-list { display: grid; gap: 9px }
.case-item {
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--btn-bg);
  color: var(--muted);
  font-size: 12px;
}
.case-item b { color: #aa9aff }
[data-theme="light"] .case-item b { color: #6d4fe8 }

.ai-grid { grid-template-columns: 1fr 1fr }
.ai-card {
  border: 1px solid rgba(102,222,196,.17);
  border-radius: 18px;
  padding: 25px;
  background: radial-gradient(circle at 85% 0, rgba(102,222,196,.08), transparent 20rem), var(--btn-bg);
  transition: background .35s, border-color .35s;
}
[data-theme="light"] .ai-card {
  border-color: rgba(29,185,154,.15);
  background: radial-gradient(circle at 85% 0, rgba(29,185,154,.05), transparent 20rem), var(--btn-bg);
}
.ai-card h3 { font-size: 23px; margin: 0 0 8px }
.flow { display: grid; grid-template-columns: repeat(3,1fr); gap: 9px; margin-top: 17px }
.node { padding: 14px; border: 1px solid var(--line); border-radius: 12px; background: var(--btn-bg) }
.node strong { display: block; font-size: 11px }
.node span { color: var(--muted); font-size: 10px }

/* Stats */
.stats { display: grid; grid-template-columns: repeat(4,1fr); gap: 9px; min-width: 420px }
.stat { border: 1px solid var(--line); border-radius: 13px; padding: 15px; background: var(--btn-bg); transition: transform .2s }
.stat:hover { transform: translateY(-2px) }
.stat strong { display: block; font-size: 22px; letter-spacing: -.05em }
.stat span { font-size: 10px; color: var(--muted) }

/* Contact */
.contact { text-align: center; max-width: 850px; margin: auto }
.contact-box {
  border: 1px solid rgba(141,115,255,.24);
  border-radius: 25px;
  padding: 55px 30px;
  background: radial-gradient(circle at 50% 0, rgba(141,115,255,.16), transparent 55%), var(--btn-bg);
  transition: background .35s, border-color .35s;
}
[data-theme="light"] .contact-box {
  border-color: rgba(109,79,232,.18);
  background: radial-gradient(circle at 50% 0, rgba(109,79,232,.08), transparent 55%), var(--btn-bg);
}
.contact p { color: var(--muted); font-size: 15px; max-width: 620px; margin: 0 auto 24px }
.contact-actions { display: flex; justify-content: center; flex-wrap: wrap; gap: 9px }

/* Work With Me specific styles */
.wwm-services {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
}
.wwm-card {
  background: var(--glass-bg);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--line);
  padding: 32px;
  border-radius: 24px;
  transition: transform 0.3s, border-color 0.3s, box-shadow 0.3s;
  text-align: center;
}
.wwm-card:hover {
  transform: translateY(-5px);
  border-color: var(--purple);
  box-shadow: 0 10px 30px rgba(109, 79, 232, 0.1);
}
.wwm-card i {
  font-size: 32px;
  color: var(--purple);
  margin-bottom: 20px;
}
.wwm-card h3 {
  font-size: 22px;
  margin-bottom: 12px;
  color: var(--text);
}
.wwm-card p {
  color: var(--muted);
  font-size: 15px;
  line-height: 1.6;
}

.process-details {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 30px;
  margin-top: 40px;
}
.p-step {
  background: var(--glass-bg);
  border: 1px solid var(--line);
  padding: 24px;
  border-radius: 20px;
}
.p-step h4 {
  font-size: 18px;
  margin-bottom: 12px;
  color: var(--purple);
}
.p-step p {
  font-size: 14.5px;
  color: var(--muted);
  line-height: 1.6;
}

/* Footer */
footer {
  padding: 25px 0 40px 0;
  color: var(--dim);
  font-size: 11px;
}
.footer-content {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
}
.footer-social {
  display: flex;
  justify-content: center;
  gap: 18px;
}
.footer-social a {
  color: var(--dim);
  font-size: 18px;
  transition: transform 0.3s, color 0.3s;
}
.footer-social a:hover {
  color: var(--purple);
  transform: translateY(-3px);
}
[data-theme="light"] .footer-social a:hover {
  color: #6d4fe8;
}

/* --- Responsive --- */
@media (max-width: 950px) {
  .menu { display: none }
  .status { display: none }
  .nav-controls .custom-lang-select { display: none }
  .menu-toggle { display: flex }
  .hero, .about, .case-grid, .ai-grid { grid-template-columns: 1fr }
  .terminal { display: none }
  .skills { grid-template-columns: 1fr 1fr }
  .stats { min-width: 0 }
}
@media (max-width: 650px) {
  .nav-inner { height: 68px }
  .nav-avatar { width: 36px; height: 36px; flex-basis: 36px }
  .brand small { font-size: 8px }
  .container { width: min(100% - 30px, var(--max)) }
  section { padding: 72px 0 }
  .hero { min-height: auto; padding-top: 45px }
  h1 { font-size: 49px }
  .lead { font-size: 16px }
  .skills, .projects { grid-template-columns: 1fr }
  .featured { grid-column: auto }
  .stats { grid-template-columns: 1fr 1fr }
  .flow { grid-template-columns: 1fr }
  .section-head { display: block }
  .intro { margin-top: 15px }
  .profile-photo { width: 250px; height: 333px }
  .contact-meta { grid-template-columns: 1fr }
  .kg-container { height: 340px }
  
  .left-sidebar-trigger {
    padding: 10px 8px;
    font-size: 14px;
    border-radius: 0 8px 8px 0;
  }
  .left-sidebar-trigger:hover {
    padding-left: 12px;
  }
}

/* ==========================================================================
   Knowledge Graph Canvas
   ========================================================================== */
.kg-wrapper {
  margin-top: 28px;
  border: 1px solid var(--line);
  border-radius: 22px;
  overflow: hidden;
  background: linear-gradient(145deg, var(--glass-from), var(--glass-to));
  transition: background .35s ease, border-color .35s ease;
}
.kg-header {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 14px 20px;
  border-bottom: 1px solid var(--line);
  font-size: 11px;
  font-weight: 800;
  letter-spacing: .06em;
  text-transform: uppercase;
  color: var(--muted);
}
.kg-header i {
  color: var(--purple);
  font-size: 13px;
}
.kg-container {
  width: 100%;
  height: 520px;
  position: relative;
}
.kg-container canvas {
  display: block;
  width: 100%;
  height: 100%;
}
.kg-hint {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 10px 16px;
  border-top: 1px solid var(--line);
  color: var(--dim);
  font-size: 10px;
  font-weight: 600;
}
.kg-hint i {
  font-size: 11px;
  color: var(--purple);
}

/* Project Hover Effect */
.project { cursor: pointer; transition: transform 0.2s, border-color 0.2s, box-shadow 0.2s; }
.project:hover { transform: translateY(-4px); border-color: var(--accent); box-shadow: 0 10px 25px rgba(0,0,0,0.2); }

/* Project Modal */
.project-modal {
  position: fixed; top: 0; left: 0; width: 100vw; height: 100vh;
  z-index: 9999; display: flex; align-items: center; justify-content: center;
  opacity: 0; pointer-events: none; transition: opacity 0.3s ease;
}
.project-modal.active { opacity: 1; pointer-events: auto; }
.project-modal-backdrop {
  position: absolute; top: 0; left: 0; width: 100%; height: 100%;
  background: var(--bg); opacity: 0.85; backdrop-filter: blur(8px);
}
.project-modal-content {
  position: relative; width: 80%; height: 80%; max-width: 900px;
  background: var(--card); border: 1px solid var(--line);
  border-radius: 16px; overflow-y: auto; padding: 40px;
  transform: translateY(20px); transition: transform 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
}
.project-modal.active .project-modal-content { transform: translateY(0); }
.project-modal-close {
  position: absolute; top: 20px; right: 20px; background: transparent; border: none;
  color: var(--text); font-size: 24px; cursor: pointer; opacity: 0.7; transition: opacity 0.2s;
}
.project-modal-close:hover { opacity: 1; }
.pm-title { font-size: 28px; margin-bottom: 8px; color: var(--text); font-weight: 700; }
.pm-meta { display: flex; flex-direction: column; gap: 8px; margin-bottom: 25px; font-size: 14px; color: var(--muted); border-bottom: 1px solid var(--line); padding-bottom: 20px; }
.pm-meta div i { margin-right: 6px; color: var(--purple); width: 16px; text-align: center; }
.pm-meta strong { color: var(--text); }
.pm-notice { display: flex; align-items: flex-start; gap: 10px; background: rgba(230, 153, 0, 0.1); border: 1px solid rgba(230, 153, 0, 0.2); color: #d98200; padding: 12px 16px; border-radius: 8px; font-size: 13px; font-weight: 500; margin-bottom: 24px; line-height: 1.5; }
.pm-notice i { font-size: 14px; margin-top: 2px; }
.pm-section { margin-bottom: 24px; }
.pm-section h4 { font-size: 16px; color: var(--text); margin-bottom: 10px; display: flex; align-items: center; gap: 8px; }
.pm-section h4 i { color: var(--purple); }
.pm-section p { font-size: 15px; color: var(--muted); line-height: 1.7; margin: 0; }
.pm-link { display: inline-flex; align-items: center; gap: 8px; padding: 8px 16px; background: rgba(141, 115, 255, 0.1); color: var(--purple); border-radius: 20px; font-size: 13px; font-weight: 600; text-decoration: none; border: 1px solid rgba(141, 115, 255, 0.2); }
.pm-link:hover { background: rgba(141, 115, 255, 0.2); }


/* Lightbox Styles */
.lightbox {
  display: none;
  position: fixed;
  z-index: 10000;
  padding: 40px;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.9);
  align-items: center;
  justify-content: center;
  flex-direction: column;
}
.lightbox.active {
  display: flex;
}
.lightbox-close {
  position: absolute;
  top: 20px;
  right: 30px;
  color: #fff;
  font-size: 30px;
  cursor: pointer;
  z-index: 10001;
}
.lightbox-prev, .lightbox-next {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  color: #fff;
  font-size: 35px;
  cursor: pointer;
  user-select: none;
  padding: 20px;
  z-index: 10001;
}
.lightbox-prev { left: 10px; }
.lightbox-next { right: 10px; }
.lightbox-prev:hover, .lightbox-next:hover, .lightbox-close:hover {
  color: #8d73ff;
}
#lightbox-img {
  max-width: 90%;
  max-height: calc(100vh - 220px);
  object-fit: contain;
  border-radius: 8px;
  box-shadow: 0 4px 20px rgba(0,0,0,0.5);
  transition: opacity 0.2s;
}
.lightbox-counter {
  color: #ccc;
  margin-top: 15px;
  font-size: 14px;
}

.lightbox-thumbnails {
  display: flex;
  gap: 12px;
  margin-top: 15px;
  overflow-x: auto;
  max-width: 90%;
  padding: 5px;
}
.lightbox-thumbnails::-webkit-scrollbar {
  height: 6px;
}
.lightbox-thumbnails::-webkit-scrollbar-thumb {
  background: #333;
  border-radius: 4px;
}
.lightbox-thumbnails img {
  height: 60px;
  width: auto;
  border-radius: 4px;
  cursor: pointer;
  opacity: 0.4;
  transition: opacity 0.2s, border 0.2s, transform 0.2s;
  border: 2px solid transparent;
}
.lightbox-thumbnails img:hover {
  opacity: 0.8;
  transform: scale(1.05);
}
.lightbox-thumbnails img.active {
  opacity: 1;
  border-color: #8d73ff;
  transform: scale(1.05);
}
/* Floating Contacts */
.floating-contacts {
  position: fixed;
  bottom: 20px;
  right: 20px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  z-index: 999;
}
.fc-btn {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 21px;
  text-decoration: none;
  box-shadow: 0 6px 16px rgba(0,0,0,0.3);
  transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1), box-shadow 0.3s;
}
.fc-btn:hover {
  transform: translateY(-5px) scale(1.08);
  box-shadow: 0 10px 24px rgba(0,0,0,0.4);
  color: #fff;
}
.fc-zalo { background: #0068ff; }
.fc-telegram { background: #24A1DE; }
[data-theme="light"] .fc-btn {
  box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}
[data-theme="light"] .fc-btn:hover {
  box-shadow: 0 8px 20px rgba(0,0,0,0.25);
}

.fc-top {
  background: var(--glass-bg);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--line);
  color: var(--text);
  opacity: 0;
  visibility: hidden;
  transform: translateY(20px);
  transition: opacity 0.3s, visibility 0.3s, transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1), box-shadow 0.3s, border-color 0.3s;
  cursor: pointer;
}
.fc-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}
.fc-top:hover {
  border-color: var(--purple);
  color: var(--purple);
}

/* Builder */
.builder-wrapper {
  display: flex;
  gap: 20px;
  background: var(--glass-bg);
  border: 1px solid var(--line);
  border-radius: 24px;
  overflow: hidden;
  height: 600px;
  text-align: left;
}
.builder-toolbar {
  width: 250px;
  background: rgba(0,0,0,0.2);
  border-right: 1px solid var(--line);
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
[data-theme="light"] .builder-toolbar { background: rgba(0,0,0,0.03); }
.builder-toolbar h4 { margin-bottom: 10px; font-size: 16px; }
.draggable-item {
  background: var(--glass-bg);
  border: 1px solid var(--line);
  padding: 12px 16px;
  border-radius: 8px;
  cursor: grab;
  font-size: 14px;
  font-weight: 500;
  display: flex;
  align-items: center;
  gap: 10px;
  transition: transform 0.2s, border-color 0.2s;
}
.draggable-item:active { cursor: grabbing; transform: scale(0.98); }
.draggable-item:hover { border-color: var(--purple); }

.builder-canvas {
  flex: 1;
  padding: 30px;
  overflow-y: auto;
  position: relative;
  background: var(--bg);
}
[data-theme="light"] .builder-canvas { background: #fff; }
.builder-canvas.drag-over {
  background: rgba(109, 79, 232, 0.05);
  box-shadow: inset 0 0 0 2px var(--purple);
}
.empty-state {
  position: absolute;
  top: 50%; left: 50%;
  transform: translate(-50%, -50%);
  color: var(--text-muted);
  pointer-events: none;
}

/* Dropped elements */
.builder-element {
  position: relative;
  padding: 15px;
  border: 1px dashed var(--line);
  margin-bottom: 15px;
  border-radius: 8px;
  background: var(--glass-bg);
}
.builder-element:hover { border-color: var(--purple); }
.builder-element .remove-btn {
  position: absolute;
  top: -10px; right: -10px;
  width: 24px; height: 24px;
  background: #ff4d4f;
  color: #fff;
  border-radius: 50%;
  border: none;
  cursor: pointer;
  display: none;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  z-index: 10;
}
.builder-element:hover > .remove-btn { display: flex; }

.builder-row { display: flex; gap: 15px; }
.builder-col {
  flex: 1;
  border: 1px dashed var(--line);
  min-height: 80px;
  padding: 10px;
  border-radius: 6px;
  background: rgba(0,0,0,0.1);
}
.builder-col.drag-over { background: rgba(109, 79, 232, 0.1); }
[data-theme="light"] .builder-col { background: rgba(0,0,0,0.03); }

/* Components Appearance */
.builder-element h2 { margin: 0; font-size: 24px; }
.builder-element p { margin: 0; color: var(--text-muted); }
.builder-element .btn { margin: 0; display: inline-block; }

/* Preview Modal */
.preview-modal {
  position: fixed;
  top: 0; left: 0; width: 100%; height: 100%;
  background: var(--bg);
  z-index: 99999;
  display: flex;
  flex-direction: column;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s, visibility 0.3s;
}
.preview-modal.open { opacity: 1; visibility: visible; }
.preview-header {
  padding: 15px 30px;
  border-bottom: 1px solid var(--line);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-weight: 600;
  background: var(--glass-bg);
}
.preview-close {
  background: transparent;
  border: none;
  color: var(--text);
  font-size: 20px;
  cursor: pointer;
}
.preview-body {
  flex: 1;
  padding: 40px;
  overflow-y: auto;
  max-width: 1200px;
  margin: 0 auto;
  width: 100%;
}
.preview-body .builder-element {
  border: none;
  background: transparent;
  padding: 0;
  margin-bottom: 20px;
}
.preview-body .builder-col {
  border: none;
  background: transparent;
  padding: 0;
}