/* ============================================================
   K Venkata Sudeep — Portfolio Stylesheet
   Dark Cyber / Neon Tech Theme
   ============================================================ */

/* ── DESIGN TOKENS ── */
:root {
  --bg-dark: #07090e;
  --bg-body: #0b0f19;
  --bg-card: rgba(15, 23, 42, 0.65);
  --bg-card-hover: rgba(24, 35, 61, 0.85);
  --bg-section-alt: #0a0e1a;

  --cyan: #00f2fe;
  --cyan-bright: #38bdf8;
  --cyan-glow: rgba(0, 242, 254, 0.25);
  --cyan-dim: rgba(56, 189, 248, 0.12);

  --violet: #a855f7;
  --violet-bright: #c084fc;
  --violet-glow: rgba(168, 85, 247, 0.25);
  --violet-dim: rgba(168, 85, 247, 0.12);

  --text-main: #f8fafc;
  --text-sub: #cbd5e1;
  --text-muted: #64748b;
  --text-dim: #475569;

  --line: rgba(255, 255, 255, 0.08);
  --line-glow: rgba(56, 189, 248, 0.25);
  --dot: rgba(56, 189, 248, 0.15);

  --mono: 'JetBrains Mono', monospace;
  --serif: 'Space Grotesk', sans-serif;
  --sans: 'Outfit', 'DM Sans', sans-serif;
}

/* ── CUSTOM SCROLLBAR ── */
::-webkit-scrollbar {
  width: 8px;
}

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

::-webkit-scrollbar-thumb {
  background: #1e293b;
  border-radius: 4px;
  border: 1px solid var(--line);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--cyan-bright);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  background-color: var(--bg-dark);
}

body {
  font-family: var(--sans);
  background-color: var(--bg-body);
  color: var(--text-main);
  line-height: 1.7;
  overflow-x: hidden;
  position: relative;
}

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

ul {
  list-style: none;
}

/* ── INTERACTIVE NETWORK BACKGROUND (canvas) ── */
.bg-network {
  position: fixed;
  inset: 0;
  /* Sections like #home paint their own near-opaque background and sit
     in the same default paint layer as z-index:0 — since they come later
     in the document, they'd cover a z-index:0 canvas. Explicit z-index:1
     lifts the canvas above every section background; it still stays
     under real content (.container etc.), which is also z-index:1 but
     appears later in the DOM, so it wins the paint order. */
  z-index: 1;
  pointer-events: none;
  display: block;
  opacity: 0.5;
}

@media (max-width: 600px) {
  .bg-network {
    opacity: 0.45;
  }
}

/* ── AMBIENT CYBER BACKGROUND GLOWS ── */
.bg-glow-container {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}

.bg-glow {
  position: absolute;
  border-radius: 50%;
  filter: blur(130px);
  opacity: 0.18;
  animation: floatGlow 18s ease-in-out infinite alternate;
}

.glow-cyan {
  width: 550px;
  height: 550px;
  background: #00f2fe;
  top: -10%;
  left: -10%;
}

.glow-violet {
  width: 600px;
  height: 600px;
  background: #a855f7;
  top: 40%;
  right: -15%;
  animation-delay: -6s;
}

.glow-blue {
  width: 500px;
  height: 500px;
  background: #3b82f6;
  bottom: 5%;
  left: 20%;
  animation-delay: -12s;
}

@keyframes floatGlow {
  0% {
    transform: translate(0, 0) scale(1);
  }

  50% {
    transform: translate(60px, 40px) scale(1.1);
  }

  100% {
    transform: translate(-40px, 80px) scale(0.95);
  }
}

/* ── SCROLL PROGRESS BAR ── */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  z-index: 300;
  background: transparent;
  pointer-events: none;
}

.scroll-progress span {
  display: block;
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--cyan), var(--violet-bright));
  box-shadow: 0 0 10px var(--cyan-glow);
  transition: width 0.1s linear;
}

/* ── CUSTOM CURSOR GLOW ── */
.cursor-glow {
  position: fixed;
  top: 0;
  left: 0;
  width: 420px;
  height: 420px;
  margin-left: -210px;
  margin-top: -210px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(0, 242, 254, 0.13) 0%, rgba(168, 85, 247, 0.07) 45%, transparent 70%);
  pointer-events: none;
  z-index: 1;
  opacity: 0;
  mix-blend-mode: screen;
  transition: opacity 0.4s ease;
  transform: translate3d(-1000px, -1000px, 0);
  will-change: transform;
}

.cursor-glow.active {
  opacity: 1;
}

@media (hover: none), (pointer: coarse) {
  .cursor-glow {
    display: none;
  }
}

/* ── UTILITY ── */
.container {
  max-width: 1040px;
  margin: 0 auto;
  padding: 0 2rem;
  position: relative;
  z-index: 1;
}

/* ============================================================
   NAVIGATION
   ============================================================ */
header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 200;
  background: rgba(11, 15, 25, 0.75);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--line);
  transition: all 0.3s ease;
}

header.scrolled {
  border-bottom-color: rgba(56, 189, 248, 0.25);
  box-shadow: 0 10px 30px -10px rgba(0, 0, 0, 0.8), 0 0 20px rgba(0, 242, 254, 0.05);
}

nav.container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 70px;
}

.logo {
  font-family: var(--mono);
  font-size: 0.9rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.logo-img {
  width: 26px;
  height: 26px;
  border-radius: 6px;
  transition: transform 0.3s ease, filter 0.3s ease;
}

.logo:hover .logo-img {
  transform: rotate(8deg) scale(1.1);
  filter: drop-shadow(0 0 8px var(--cyan));
}

.logo::before {
  content: '';
  width: 8px;
  height: 8px;
  background: var(--cyan);
  border-radius: 50%;
  box-shadow: 0 0 10px var(--cyan);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 2.2rem;
}

.nav-links a {
  font-family: var(--mono);
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
  position: relative;
  transition: color 0.25s ease;
}

.nav-links a::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: -4px;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--cyan), var(--violet));
  border-radius: 2px;
  transition: width 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  box-shadow: 0 0 8px var(--cyan);
}

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

.nav-links a:hover::after,
.nav-links a.active::after {
  width: 100%;
}

.nav-links a.nav-resume {
  color: var(--cyan-bright);
  font-weight: 600;
  background: var(--cyan-dim);
  border: 1px solid rgba(56, 189, 248, 0.3);
  border-radius: 6px;
  padding: 0.4rem 1rem;
  transition: all 0.25s ease;
}

.nav-links a.nav-resume::after {
  display: none;
}

.nav-links a.nav-resume:hover {
  background: var(--cyan);
  color: var(--bg-dark);
  border-color: var(--cyan);
  box-shadow: 0 0 20px var(--cyan-glow);
  transform: translateY(-1px);
}

/* ── MOBILE NAV TOGGLE ── */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 38px;
  height: 38px;
  background: transparent;
  border: 1px solid var(--line);
  border-radius: 8px;
  cursor: pointer;
  z-index: 210;
}

.nav-toggle span {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--cyan-bright);
  border-radius: 2px;
  transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1), opacity 0.3s ease;
}

.nav-toggle[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

@media (max-width: 720px) {
  .nav-toggle {
    display: flex;
  }

  .nav-links {
    position: fixed;
    top: 70px;
    right: 0;
    left: 0;
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    background: rgba(9, 13, 22, 0.97);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--line);
    padding: 0.5rem 2rem;
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    transition: max-height 0.4s cubic-bezier(0.16, 1, 0.3, 1), opacity 0.3s ease, padding 0.4s ease;
  }

  .nav-links.open {
    max-height: 420px;
    opacity: 1;
    padding: 1rem 2rem 1.6rem;
  }

  .nav-links li {
    width: 100%;
    border-bottom: 1px solid var(--line);
  }

  .nav-links li:last-child {
    border-bottom: none;
    padding-top: 0.8rem;
  }

  .nav-links a {
    display: block;
    padding: 0.9rem 0;
  }

  .nav-links a.nav-resume {
    display: inline-flex;
  }
}

/* ============================================================
   HERO
   ============================================================ */
#home {
  padding-top: 70px;
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  background: radial-gradient(circle at 50% 30%, rgba(15, 23, 42, 0.8) 0%, var(--bg-body) 70%);
}

/* Futuristic Cyber Grid background */
#home::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, rgba(56, 189, 248, 0.04) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(56, 189, 248, 0.04) 1px, transparent 1px);
  background-size: 50px 50px;
  mask-image: radial-gradient(ellipse at center, rgba(0, 0, 0, 1) 20%, rgba(0, 0, 0, 0) 75%);
  -webkit-mask-image: radial-gradient(ellipse at center, rgba(0, 0, 0, 1) 20%, rgba(0, 0, 0, 0) 75%);
  pointer-events: none;
}

.hero-inner {
  position: relative;
  padding: 6rem 0 4rem;
  margin-top: -2rem;
}

.hero-eyebrow {
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--cyan-bright);
  margin-bottom: 1.4rem;
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  background: var(--cyan-dim);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid rgba(56, 189, 248, 0.25);
  padding: 0.35rem 0.9rem;
  border-radius: 30px;
  opacity: 0;
  animation: rise 0.7s 0.2s ease forwards;
}

.hero-eyebrow::before {
  content: '';
  width: 6px;
  height: 6px;
  background: var(--cyan);
  border-radius: 50%;
  box-shadow: 0 0 8px var(--cyan);
  animation: certPulse 2s infinite;
}

.hero-name {
  font-family: var(--serif);
  font-size: clamp(3rem, 7.5vw, 5.8rem);
  font-weight: 700;
  line-height: 1.05;
  color: var(--text-main);
  margin-bottom: 0.8rem;
  letter-spacing: -0.02em;
  opacity: 0;
  animation: rise 0.7s 0.4s ease forwards;
}

.hero-name em {
  font-style: normal;
  background: linear-gradient(135deg, var(--cyan) 0%, #38bdf8 40%, var(--violet-bright) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
  filter: drop-shadow(0 0 25px rgba(0, 242, 254, 0.3));
}

.hero-role {
  font-family: var(--mono);
  font-size: 1.1rem;
  color: var(--text-sub);
  margin-bottom: 2rem;
  opacity: 0;
  animation: rise 0.7s 0.6s ease forwards;
  display: flex;
  align-items: center;
  gap: 0.2rem;
}

.role-prefix {
  color: var(--violet-bright);
  font-weight: 600;
}

.role-text {
  color: var(--cyan-bright);
  font-weight: 500;
}

.type-cursor {
  font-family: var(--mono);
  color: var(--cyan);
  font-weight: 400;
  margin-left: 2px;
  animation: blinkCursor 0.8s infinite;
}

@keyframes blinkCursor {

  0%,
  100% {
    opacity: 1;
  }

  50% {
    opacity: 0;
  }
}

.hero-desc {
  max-width: 580px;
  font-size: 1.05rem;
  color: var(--text-sub);
  line-height: 1.85;
  margin-bottom: 2.8rem;
  opacity: 0;
  animation: rise 0.7s 0.8s ease forwards;
}

.hero-actions {
  display: flex;
  gap: 1.2rem;
  flex-wrap: wrap;
  opacity: 0;
  animation: rise 0.7s 1s ease forwards;
}

/* ── BUTTONS ── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1.8rem;
  font-family: var(--mono);
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  border-radius: 8px;
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  cursor: pointer;
  border: none;
  position: relative;
  overflow: hidden;
}

.btn-dark {
  background: linear-gradient(135deg, var(--cyan) 0%, #0284c7 100%);
  color: #040914;
  box-shadow: 0 0 25px rgba(0, 242, 254, 0.35);
}

.btn-dark:hover {
  transform: translate(var(--mx, 0px), calc(-3px + var(--my, 0px)));
  box-shadow: 0 0 35px rgba(0, 242, 254, 0.6);
  background: linear-gradient(135deg, #38bdf8 0%, var(--cyan) 100%);
}

.btn-ghost {
  background: rgba(15, 23, 42, 0.6);
  color: var(--text-main);
  border: 1px solid rgba(56, 189, 248, 0.25);
  backdrop-filter: blur(12px);
}

.btn-ghost:hover {
  border-color: var(--cyan);
  color: var(--cyan-bright);
  background: var(--cyan-dim);
  box-shadow: 0 0 20px var(--cyan-glow);
  transform: translate(var(--mx, 0px), calc(-3px + var(--my, 0px)));
}

.btn-white {
  background: linear-gradient(135deg, #ffffff 0%, #e2e8f0 100%);
  color: #070a12;
  font-weight: 700;
  box-shadow: 0 0 25px rgba(255, 255, 255, 0.2);
  display: inline-flex;
  margin-bottom: 2.5rem;
}

.btn-white:hover {
  box-shadow: 0 0 35px rgba(255, 255, 255, 0.4);
  transform: translate(var(--mx, 0px), calc(-3px + var(--my, 0px)));
}

.btn-full {
  width: 100%;
  justify-content: center;
}

/* ── KEYFRAMES ── */
@keyframes rise {
  from {
    opacity: 0;
    transform: translateY(24px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ============================================================
   SHARED SECTION STYLES
   ============================================================ */
.section {
  padding: 7.5rem 0;
  border-top: 1px solid var(--line);
  opacity: 0;
  transform: translateY(32px);
  transition: opacity 0.7s cubic-bezier(0.16, 1, 0.3, 1), transform 0.7s cubic-bezier(0.16, 1, 0.3, 1);
  position: relative;
}

.section.visible {
  opacity: 1;
  transform: none;
}

.sec-label {
  font-family: var(--mono);
  font-size: 0.75rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--cyan-bright);
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.sec-label::after {
  content: '';
  height: 1px;
  width: 60px;
  background: linear-gradient(90deg, var(--cyan-bright), transparent);
}

.sec-title {
  font-family: var(--serif);
  font-size: clamp(2rem, 4vw, 2.8rem);
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 3.5rem;
  letter-spacing: -0.01em;
}

/* ============================================================
   ABOUT
   ============================================================ */
#about {
  background: var(--bg-section-alt);
}

.about-content {
  max-width: 780px;
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 3rem;
  backdrop-filter: blur(16px);
  box-shadow: 0 20px 40px -15px rgba(0, 0, 0, 0.5);
  position: relative;
  overflow: hidden;
  transition: transform 0.35s cubic-bezier(0.16, 1, 0.3, 1), border-color 0.35s ease;
}

.about-content:hover {
  border-color: rgba(56, 189, 248, 0.3);
  transform: perspective(1000px) rotateX(var(--rotate-x, 0deg)) rotateY(var(--rotate-y, 0deg));
}

.about-content::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: linear-gradient(to bottom, var(--cyan), var(--violet));
  z-index: 1;
}

/* Mouse-tracked spotlight for skill cards and the about panel */
.skill-card::after,
.about-content::after {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(320px circle at var(--mouse-x, 50%) var(--mouse-y, 50%), rgba(56, 189, 248, 0.14), transparent 62%);
  opacity: 0;
  transition: opacity 0.4s ease;
  pointer-events: none;
  mix-blend-mode: screen;
  z-index: 0;
}

.skill-card:hover::after,
.about-content:hover::after {
  opacity: 1;
}

.about-content p {
  font-size: 1.05rem;
  color: var(--text-sub);
  line-height: 1.9;
  margin-bottom: 1.5rem;
}

.about-content p:last-child {
  margin-bottom: 0;
}

.about-content p strong {
  color: var(--cyan-bright);
  font-weight: 600;
}

/* ============================================================
   TECHNICAL STACK
   ============================================================ */
#skills {
  background: var(--bg-body);
}

.skills-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1.25rem;
}

.skill-card {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 1.5rem;
  backdrop-filter: blur(16px);
  transition: all 0.35s cubic-bezier(0.16, 1, 0.3, 1);
  position: relative;
  overflow: hidden;
}

.skill-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, var(--cyan), var(--violet));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.4s ease;
}

.skill-card:hover {
  transform: translateY(-6px) perspective(900px) rotateX(var(--rotate-x, 0deg)) rotateY(var(--rotate-y, 0deg));
  border-color: rgba(56, 189, 248, 0.4);
  background: var(--bg-card-hover);
  box-shadow: 0 20px 40px -15px rgba(0, 242, 254, 0.15);
}

.skill-card:hover::before {
  transform: scaleX(1);
}

#skills .skill-card:hover {
  transform: translateY(-4px);
}

.skill-card-title {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  font-family: var(--serif);
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--text-main);
  margin-bottom: 1rem;
}

.skill-category-icon {
  width: 1.35rem;
  height: 1.35rem;
  flex: 0 0 auto;
  color: var(--violet-bright);
}

.skill-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
}

.pill {
  display: inline-flex;
  max-width: 100%;
  min-width: 0;
  font-family: var(--sans);
  font-size: 0.82rem;
  font-weight: 500;
  padding: 0.4rem 0.65rem;
  line-height: 1.35;
  background: var(--cyan-dim);
  border: 1px solid rgba(56, 189, 248, 0.2);
  border-radius: 8px;
  color: var(--cyan-bright);
  transition: all 0.25s ease;
}

.pill:hover {
  border-color: var(--cyan);
  background: var(--cyan);
  color: #040914;
  box-shadow: 0 0 12px var(--cyan-glow);
}

/* ============================================================
   EDUCATION
   ============================================================ */
#education {
  background: var(--bg-dark);
}

.edu-list {
  position: relative;
  display: grid;
  gap: 2.5rem;
  margin-left: 0.55rem;
  padding: 0.2rem 0 1.2rem 2rem;
}

.edu-list::before {
  content: '';
  position: absolute;
  top: 0.55rem;
  bottom: 1.2rem;
  left: 0;
  width: 1px;
  background: var(--line);
}

.edu-item {
  position: relative;
  padding-left: 0.5rem;
}

.edu-item::before {
  content: '';
  position: absolute;
  top: 0.4rem;
  left: -2.3rem;
  width: 9px;
  height: 9px;
  border: 2px solid var(--violet-bright);
  border-radius: 50%;
  background: var(--bg-dark);
  box-shadow: 0 0 0 5px var(--violet-dim);
}

.edu-degree {
  font-family: var(--serif);
  font-size: 1.3rem;
  font-weight: 600;
  color: var(--text-main);
  margin: 0.15rem 0 0.1rem;
}

.edu-inst {
  font-size: 0.95rem;
  color: var(--text-sub);
  line-height: 1.5;
}

.edu-loc {
  font-size: 0.9rem;
  color: var(--text-sub);
  margin-top: 0.2rem;
}

.edu-year {
  font-family: var(--mono);
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--violet-bright);
  letter-spacing: 0.08em;
}

/* ============================================================
   CERTIFICATIONS
   ============================================================ */
#certifications {
  background: var(--bg-body);
}

.cert-list {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.cert-card {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 2.5rem 3rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 2rem;
  backdrop-filter: blur(16px);
  position: relative;
  overflow: hidden;
  opacity: 0;
  transform: translateY(32px) scale(0.98);
  transition:
    opacity 0.65s cubic-bezier(0.16, 1, 0.3, 1),
    transform 0.65s cubic-bezier(0.16, 1, 0.3, 1),
    border-color 0.35s ease,
    box-shadow 0.35s ease,
    background-color 0.35s ease;
}

#certifications.visible .cert-card:nth-child(1) {
  opacity: 1;
  transform: translateY(0) scale(1);
  transition-delay: 0.15s;
}

#certifications.visible .cert-card:nth-child(2) {
  opacity: 1;
  transform: translateY(0) scale(1);
  transition-delay: 0.32s;
}

#certifications.visible .cert-card:hover {
  transform: translateY(-3px);
  border-color: rgba(56, 189, 248, 0.4);
  background: var(--bg-card-hover);
  box-shadow: 0 10px 24px -16px rgba(0, 242, 254, 0.2);
  transition-delay: 0s;
}

.cert-badge {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--cyan-bright);
  margin-bottom: 0.75rem;
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
}

.cert-pulse-dot {
  width: 8px;
  height: 8px;
  background-color: var(--cyan);
  border-radius: 50%;
  display: inline-block;
  animation: certPulse 2s infinite;
}

@keyframes certPulse {

  0%,
  100% {
    opacity: 1;
    box-shadow: 0 0 0 0 rgba(0, 242, 254, 0.6);
  }

  50% {
    opacity: 0.6;
    box-shadow: 0 0 0 8px rgba(0, 242, 254, 0);
  }
}

.cert-name {
  font-family: var(--serif);
  font-size: clamp(1.4rem, 2.5vw, 1.8rem);
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 0.4rem;
}

.cert-issuer {
  font-family: var(--mono);
  font-size: 0.85rem;
  color: var(--violet-bright);
  margin-bottom: 0.9rem;
}

.cert-desc {
  font-size: 0.95rem;
  color: var(--text-sub);
  max-width: 600px;
  line-height: 1.75;
}

.cert-action {
  flex-shrink: 0;
}

.btn-arrow {
  display: inline-block;
  transition: transform 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

.cert-card:hover .btn-arrow,
.btn:hover .btn-arrow {
  transform: translate(3px, -3px);
}

/* ============================================================
   PROJECT
   ============================================================ */
#projects {
  background: var(--bg-section-alt);
}

.project-card {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: 20px;
  padding: 3rem;
  backdrop-filter: blur(16px);
  position: relative;
  overflow: hidden;
  transition: transform 0.25s ease, border-color 0.25s ease, box-shadow 0.25s ease, background-color 0.25s ease;
}

.project-card::before {
  content: '';
  position: absolute;
  inset: 0 auto 0 0;
  width: 3px;
  background: linear-gradient(to bottom, var(--cyan), var(--violet));
  transform: scaleY(0);
  transform-origin: top;
  transition: transform 0.3s ease;
}

.project-card:hover {
  border-color: rgba(56, 189, 248, 0.45);
  box-shadow: 0 16px 32px -20px rgba(0, 242, 254, 0.32);
  background: var(--bg-card-hover);
  transform: translateY(-5px);
}

.project-card:hover::before {
  transform: scaleY(1);
}

.proj-tags {
  display: flex;
  gap: 0.7rem;
  margin-bottom: 1.5rem;
  flex-wrap: wrap;
}

.proj-tag {
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--cyan-bright);
  background: var(--cyan-dim);
  border: 1px solid rgba(56, 189, 248, 0.2);
  border-radius: 20px;
  padding: 0.25rem 0.75rem;
}

.proj-title {
  font-family: var(--serif);
  font-size: clamp(1.6rem, 2.8vw, 2.2rem);
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 2rem;
  max-width: 680px;
  line-height: 1.25;
}

.proj-body {
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 3rem;
  align-items: start;
}

.proj-section-head {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--violet-bright);
  margin-bottom: 0.75rem;
  margin-top: 1.8rem;
}

.proj-section-head:first-child {
  margin-top: 0;
}

.proj-text {
  font-size: 0.98rem;
  color: var(--text-sub);
  line-height: 1.85;
}

.proj-text strong {
  color: var(--cyan-bright);
  font-weight: 600;
}

.proj-sidebar-card {
  background: rgba(11, 15, 25, 0.6);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 1.6rem;
  margin-bottom: 1.4rem;
}

.proj-sidebar-card h4 {
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 1rem;
}

.tech-list {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.tech-item {
  font-family: var(--mono);
  font-size: 0.82rem;
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.tech-item::before {
  content: '▸';
  color: var(--cyan);
}

/* ============================================================
   CONTACT
   ============================================================ */
#contact {
  background: radial-gradient(circle at 50% 50%, rgba(168, 85, 247, 0.12) 0%, var(--bg-body) 80%);
}

.contact-inner {
  text-align: center;
  max-width: 680px;
  margin: 0 auto;
}

.contact-inner .sec-label {
  justify-content: center;
}

.contact-inner .sec-label::after {
  display: none;
}

.contact-sub {
  font-size: 1.1rem;
  color: var(--text-sub);
  line-height: 1.8;
  margin-bottom: 2.8rem;
}

.contact-links {
  display: flex;
  justify-content: center;
  gap: 2rem;
  margin-top: 1rem;
}

.contact-link {
  font-family: var(--mono);
  font-size: 0.85rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-sub);
  transition: all 0.25s ease;
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.contact-link:hover {
  color: var(--cyan-bright);
}

.contact-icon,
.btn-icon {
  flex-shrink: 0;
  transition: transform 0.25s ease;
}

.contact-link:hover .contact-icon {
  transform: translateY(-2px);
  color: var(--cyan-bright);
}

.btn-white:hover .btn-icon {
  transform: scale(1.1);
}

/* ── COPY EMAIL BUTTON ── */
.contact-cta {
  display: inline-flex;
  align-items: center;
  gap: 0.8rem;
  margin-bottom: 2.5rem;
}

.contact-cta .btn-white {
  margin-bottom: 0;
}

.copy-email-btn {
  position: relative;
  width: 46px;
  height: 46px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: rgba(15, 23, 42, 0.6);
  border: 1px solid rgba(56, 189, 248, 0.25);
  border-radius: 10px;
  color: var(--text-sub);
  cursor: pointer;
  backdrop-filter: blur(12px);
  transition: all 0.25s ease;
}

.copy-email-btn:hover {
  border-color: var(--cyan);
  color: var(--cyan-bright);
  box-shadow: 0 0 16px var(--cyan-glow);
  transform: translateY(-3px);
}

.copy-email-tooltip {
  position: absolute;
  bottom: calc(100% + 10px);
  left: 50%;
  transform: translateX(-50%) translateY(4px);
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.04em;
  white-space: nowrap;
  background: #101827;
  color: var(--text-main);
  border: 1px solid var(--line);
  padding: 0.35rem 0.7rem;
  border-radius: 6px;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease, transform 0.2s ease;
}

.copy-email-btn:hover .copy-email-tooltip {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

.copy-email-btn.copied {
  border-color: var(--cyan);
  color: var(--cyan-bright);
}

.copy-email-btn.copied .copy-email-tooltip {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
  color: var(--cyan-bright);
  border-color: rgba(56, 189, 248, 0.4);
}

/* ── BACK TO TOP ── */
.back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(15, 23, 42, 0.75);
  color: var(--cyan-bright);
  border: 1px solid rgba(56, 189, 248, 0.3);
  border-radius: 50%;
  backdrop-filter: blur(12px);
  cursor: pointer;
  z-index: 150;
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition: opacity 0.3s ease, transform 0.3s ease, visibility 0.3s, border-color 0.25s ease, box-shadow 0.25s ease;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  border-color: var(--cyan);
  box-shadow: 0 0 20px var(--cyan-glow);
  transform: translateY(-4px);
}

@media (max-width: 640px) {
  .back-to-top {
    right: 1.2rem;
    bottom: 1.2rem;
    width: 42px;
    height: 42px;
  }

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

/* ── REDUCED MOTION ── */
@media (prefers-reduced-motion: reduce) {

  .cursor-glow,
  .skill-card,
  .project-card,
  .cert-card,
  .about-content,
  .btn,
  .back-to-top {
    transition: none !important;
  }

  .cursor-glow {
    display: none;
  }

  .bg-network {
    display: none;
  }
}

/* ============================================================
   FOOTER
   ============================================================ */
.foot {
  padding: 2.5rem 0;
  border-top: 1px solid var(--line);
  background: var(--bg-dark);
  text-align: center;
}

.foot-copy {
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--text-muted);
}

/* ============================================================
   RESPONSIVE DESIGN
   ============================================================ */
@media (max-width: 868px) {
  .skills-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .proj-body {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .cert-card {
    flex-direction: column;
    align-items: flex-start;
    padding: 2rem;
  }

  .cert-action {
    width: 100%;
  }

  .cert-action .btn {
    width: 100%;
    justify-content: center;
  }
}

@media (max-width: 640px) {
  .skills-grid {
    grid-template-columns: 1fr;
  }

  .nav-links {
    gap: 1.2rem;
  }

  .nav-links a {
    font-size: 0.7rem;
  }

  .edu-list {
    gap: 2rem;
    padding-left: 1.6rem;
  }

  .edu-item::before {
    left: -1.9rem;
  }

  .edu-degree {
    font-size: 1.15rem;
  }
}