/* =============================================
   GILMAN HIKMATIYAR — PERSONAL PROFILE WEBSITE
   style.css
   ============================================= */

/* ---- CSS Variables ---- */
:root {
  --bg-primary:    #0a192f;
  --bg-secondary:  #112240;
  --bg-tertiary:   #1e3a5f;
  --accent:        #64ffda;
  --accent-dark:   #00bcd4;
  --text-primary:  #ccd6f6;
  --text-secondary:#8892b0;
  --text-white:    #e6f1ff;
  --border:        rgba(100, 255, 218, 0.15);
  --shadow:        0 10px 40px rgba(0, 0, 0, 0.5);
  --shadow-sm:     0 4px 15px rgba(0, 0, 0, 0.3);
  --radius:        12px;
  --radius-sm:     8px;
  --radius-lg:     20px;
  --transition:    0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --navbar-h:      70px;
  --font-main:     'Poppins', sans-serif;
  --font-mono:     'Fira Code', monospace;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-main);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

img, svg { display: block; max-width: 100%; }
a { text-decoration: none; color: inherit; }
ul { list-style: none; }
button { cursor: pointer; border: none; background: none; font-family: var(--font-main); }
input, textarea, button { font-family: var(--font-main); }

/* ---- Utility ---- */
.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
}

.accent { color: var(--accent); }

.section {
  padding: 96px 0;
}

.section-header {
  text-align: center;
  margin-bottom: 64px;
}

.section-label {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--accent);
  letter-spacing: 0.15em;
  text-transform: uppercase;
  margin-bottom: 10px;
}

.section-label::before { content: "// "; opacity: 0.5; }

.section-title {
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  font-weight: 700;
  color: var(--text-white);
  line-height: 1.2;
}

.section-desc {
  margin-top: 16px;
  color: var(--text-secondary);
  font-size: 1.05rem;
  max-width: 580px;
  margin-left: auto;
  margin-right: auto;
}

.sub-title {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-white);
  margin-bottom: 24px;
  position: relative;
  padding-left: 16px;
}

.sub-title::before {
  content: '';
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 4px;
  height: 100%;
  background: var(--accent);
  border-radius: 2px;
}

/* ---- Buttons ---- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  border-radius: 8px;
  font-weight: 600;
  font-size: 0.95rem;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.btn::before {
  content: '';
  position: absolute;
  inset: 0;
  background: rgba(255,255,255,0.05);
  opacity: 0;
  transition: var(--transition);
}

.btn:hover::before { opacity: 1; }

.btn-primary {
  background: var(--accent);
  color: var(--bg-primary);
  box-shadow: 0 0 20px rgba(100, 255, 218, 0.25);
}

.btn-primary:hover {
  background: #4de8c4;
  box-shadow: 0 0 30px rgba(100, 255, 218, 0.4);
  transform: translateY(-2px);
}

.btn-outline {
  border: 1.5px solid var(--accent);
  color: var(--accent);
}

.btn-outline:hover {
  background: rgba(100, 255, 218, 0.08);
  transform: translateY(-2px);
}

.btn-ghost {
  color: var(--accent);
  border: 1px solid var(--border);
}

.btn-ghost:hover {
  border-color: var(--accent);
  background: rgba(100, 255, 218, 0.05);
}

.btn-sm {
  padding: 7px 18px;
  font-size: 0.82rem;
  border-radius: 6px;
}

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

/* ---- Animations ---- */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(30px); }
  to   { opacity: 1; transform: translateY(0); }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to   { opacity: 1; }
}

@keyframes float {
  0%, 100% { transform: translateY(0px); }
  50%       { transform: translateY(-16px); }
}

@keyframes pulse {
  0%, 100% { transform: scale(1); opacity: 0.4; }
  50%       { transform: scale(1.4); opacity: 0; }
}

@keyframes pulse2 {
  0%, 100% { transform: scale(1); opacity: 0.2; }
  50%       { transform: scale(1.6); opacity: 0; }
}

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

@keyframes scrollBounce {
  0%, 100% { transform: translateY(0) rotate(45deg); }
  50%       { transform: translateY(6px) rotate(45deg); }
}

@keyframes shimmer {
  0%   { background-position: -200% center; }
  100% { background-position: 200% center; }
}

.fade-in {
  animation: fadeInUp 0.9s ease both;
}

.delay-1 { animation-delay: 0.2s; }
.delay-2 { animation-delay: 0.4s; }
.delay-3 { animation-delay: 0.6s; }

/* Scroll reveal */
.reveal {
  opacity: 0;
  transform: translateY(32px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

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

.reveal.delay-1 { transition-delay: 0.15s; }
.reveal.delay-2 { transition-delay: 0.30s; }
.reveal.delay-3 { transition-delay: 0.45s; }

/* =============================================
   NAVBAR
   ============================================= */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 999;
  height: var(--navbar-h);
  display: flex;
  align-items: center;
  transition: background var(--transition), box-shadow var(--transition), backdrop-filter var(--transition);
}

.navbar.scrolled {
  background: rgba(10, 25, 47, 0.92);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  box-shadow: 0 2px 20px rgba(0,0,0,0.4);
}

.nav-container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-family: var(--font-mono);
  font-size: 1.25rem;
  font-weight: 500;
  color: var(--accent);
  letter-spacing: 0.05em;
  transition: var(--transition);
}

.nav-logo:hover { opacity: 0.8; }

.logo-bracket { color: var(--accent); opacity: 0.7; }

.nav-links {
  display: flex;
  align-items: center;
  gap: 36px;
}

.nav-link {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color var(--transition);
  position: relative;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -3px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent);
  transition: width var(--transition);
  border-radius: 2px;
}

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

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

/* Hamburger */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 6px;
  z-index: 1001;
}

.hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--accent);
  border-radius: 2px;
  transition: var(--transition);
}

.hamburger.open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.hamburger.open span:nth-child(2) {
  opacity: 0;
  transform: scaleX(0);
}

.hamburger.open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* =============================================
   HERO SECTION
   ============================================= */
.hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  position: relative;
  overflow: hidden;
  padding: calc(var(--navbar-h) + 40px) 24px 80px;
}

.hero-bg-shapes {
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 0;
}

.shape {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  opacity: 0.12;
}

.shape-1 {
  width: 500px;
  height: 500px;
  background: var(--accent);
  top: -150px;
  right: -100px;
}

.shape-2 {
  width: 350px;
  height: 350px;
  background: #0d6efd;
  bottom: -50px;
  left: -100px;
}

.shape-3 {
  width: 250px;
  height: 250px;
  background: var(--accent);
  top: 50%;
  left: 40%;
  opacity: 0.06;
}

.hero-container {
  max-width: 1100px;
  margin: 0 auto;
  width: 100%;
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: center;
  gap: 60px;
  position: relative;
  z-index: 1;
}

.hero-greeting {
  font-family: var(--font-mono);
  font-size: 1rem;
  color: var(--accent);
  margin-bottom: 10px;
  letter-spacing: 0.05em;
}

.hero-name {
  font-size: clamp(2.8rem, 6vw, 4.5rem);
  font-weight: 800;
  color: var(--text-white);
  line-height: 1.1;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.hero-tagline {
  font-size: clamp(1rem, 2vw, 1.3rem);
  color: var(--text-secondary);
  margin-bottom: 20px;
  min-height: 2em;
  font-family: var(--font-mono);
}

.typed-wrapper {
  display: inline-flex;
  align-items: center;
  gap: 2px;
}

.typed { color: var(--accent); }

.cursor {
  color: var(--accent);
  animation: blink 1s step-end infinite;
  font-weight: 300;
}

.hero-desc {
  color: var(--text-secondary);
  font-size: 1.05rem;
  max-width: 480px;
  margin-bottom: 36px;
  line-height: 1.8;
}

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

/* Avatar */
.hero-avatar {
  display: flex;
  justify-content: center;
  align-items: center;
  animation: float 6s ease-in-out infinite;
}

.avatar-svg {
  width: 100%;
  max-width: 400px;
  filter: drop-shadow(0 0 40px rgba(100, 255, 218, 0.15));
}

.pulse-ring {
  transform-origin: 148px 96px;
  animation: pulse 2.5s ease-out infinite;
}

.pulse-ring-2 {
  transform-origin: 148px 96px;
  animation: pulse2 2.5s ease-out infinite 0.5s;
}

/* Scroll indicator */
.scroll-indicator {
  position: absolute;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  color: var(--text-secondary);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  z-index: 1;
  opacity: 0.6;
}

.scroll-arrow {
  width: 12px;
  height: 12px;
  border-right: 2px solid var(--accent);
  border-bottom: 2px solid var(--accent);
  transform: rotate(45deg);
  animation: scrollBounce 1.5s ease-in-out infinite;
}

/* =============================================
   ABOUT SECTION
   ============================================= */
.about-section {
  background: var(--bg-secondary);
  position: relative;
}

.about-section::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--accent), transparent);
  opacity: 0.3;
}

.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: start;
}

.about-text p {
  color: var(--text-secondary);
  margin-bottom: 16px;
  font-size: 1rem;
  line-height: 1.85;
}

.about-text p strong { font-weight: 600; }

.about-stats {
  display: flex;
  gap: 32px;
  margin-top: 32px;
  flex-wrap: wrap;
}

.stat-item {
  text-align: center;
  padding: 16px 24px;
  background: var(--bg-primary);
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  min-width: 100px;
  transition: var(--transition);
}

.stat-item:hover {
  border-color: var(--accent);
  transform: translateY(-3px);
  box-shadow: 0 8px 25px rgba(100,255,218,0.1);
}

.stat-number {
  display: block;
  font-size: 1.9rem;
  font-weight: 700;
  color: var(--accent);
  line-height: 1;
  margin-bottom: 4px;
}

.stat-label {
  display: block;
  font-size: 0.75rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

/* Education Timeline */
.edu-timeline {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.edu-item {
  display: flex;
  gap: 16px;
  padding: 20px;
  background: var(--bg-primary);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  transition: var(--transition);
}

.edu-item:hover {
  border-color: var(--accent);
  transform: translateX(4px);
  box-shadow: var(--shadow-sm);
}

.edu-icon {
  width: 44px;
  height: 44px;
  background: rgba(100, 255, 218, 0.1);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  color: var(--accent);
}

.edu-icon svg { width: 20px; height: 20px; }

.edu-content h4 {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-white);
  margin-bottom: 2px;
}

.edu-place {
  font-size: 0.82rem;
  color: var(--accent);
  margin-bottom: 2px;
  font-weight: 500;
}

.edu-year {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-secondary);
  display: block;
  margin-bottom: 6px;
}

.edu-desc {
  font-size: 0.82rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* =============================================
   SKILLS SECTION
   ============================================= */
.skills-section { background: var(--bg-primary); }

.skills-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: start;
}

/* Progress bars */
.skill-bars-list {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.skill-bar-item {}

.skill-bar-label {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 8px;
}

.skill-bar-label span:first-child {
  font-size: 0.9rem;
  color: var(--text-primary);
  font-weight: 500;
}

.skill-pct {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--accent);
}

.skill-bar-track {
  width: 100%;
  height: 6px;
  background: var(--bg-tertiary);
  border-radius: 3px;
  overflow: hidden;
}

.skill-bar-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--accent-dark), var(--accent));
  border-radius: 3px;
  transition: width 1.2s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
}

.skill-bar-fill::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(90deg, transparent 0%, rgba(255,255,255,0.3) 50%, transparent 100%);
  background-size: 200% 100%;
  animation: shimmer 2s infinite;
}

/* Skill tags */
.tags-group {
  margin-bottom: 24px;
}

.tags-category {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 10px;
}

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

.tag {
  padding: 5px 14px;
  background: rgba(100, 255, 218, 0.07);
  border: 1px solid var(--border);
  border-radius: 20px;
  font-size: 0.8rem;
  color: var(--text-secondary);
  transition: var(--transition);
  font-family: var(--font-mono);
}

.tag:hover {
  background: rgba(100, 255, 218, 0.15);
  border-color: var(--accent);
  color: var(--accent);
  transform: translateY(-2px);
}

/* =============================================
   PORTFOLIO SECTION
   ============================================= */
.portfolio-section {
  background: var(--bg-secondary);
  position: relative;
}

.portfolio-filter {
  display: flex;
  justify-content: center;
  gap: 12px;
  margin-bottom: 48px;
  flex-wrap: wrap;
}

.filter-btn {
  padding: 8px 22px;
  border-radius: 20px;
  border: 1.5px solid var(--border);
  background: transparent;
  color: var(--text-secondary);
  font-size: 0.85rem;
  font-weight: 500;
  cursor: pointer;
  transition: var(--transition);
}

.filter-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.filter-btn.active {
  background: rgba(100, 255, 218, 0.12);
  border-color: var(--accent);
  color: var(--accent);
}

.portfolio-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.project-card {
  background: var(--bg-primary);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  overflow: hidden;
  transition: var(--transition);
  display: flex;
  flex-direction: column;
}

.project-card:hover {
  transform: translateY(-6px);
  border-color: rgba(100, 255, 218, 0.4);
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5), 0 0 30px rgba(100, 255, 218, 0.07);
}

.project-card.hidden {
  display: none;
}

.project-thumb {
  width: 100%;
  overflow: hidden;
  position: relative;
}

.project-thumb svg {
  width: 100%;
  height: auto;
  display: block;
  transition: transform 0.5s ease;
}

.project-card:hover .project-thumb svg {
  transform: scale(1.05);
}

.project-info {
  padding: 20px;
  display: flex;
  flex-direction: column;
  flex: 1;
  gap: 10px;
}

.project-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-white);
  line-height: 1.4;
}

.project-desc {
  font-size: 0.83rem;
  color: var(--text-secondary);
  line-height: 1.65;
  flex: 1;
}

.project-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.ptag {
  padding: 3px 10px;
  background: rgba(100, 255, 218, 0.07);
  border-radius: 4px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--accent);
  border: 1px solid var(--border);
}

.project-actions {
  display: flex;
  gap: 10px;
  margin-top: 4px;
}

/* =============================================
   CONTACT SECTION
   ============================================= */
.contact-section { background: var(--bg-primary); }

.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: start;
}

.contact-cards {
  display: flex;
  flex-direction: column;
  gap: 14px;
  margin-bottom: 24px;
}

.contact-card {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 16px 20px;
  background: var(--bg-secondary);
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  transition: var(--transition);
}

.contact-card:hover {
  border-color: var(--accent);
  transform: translateX(4px);
  box-shadow: var(--shadow-sm);
}

.contact-icon {
  width: 42px;
  height: 42px;
  background: rgba(100, 255, 218, 0.1);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent);
  flex-shrink: 0;
}

.contact-icon svg { width: 18px; height: 18px; }

.ccard-label {
  font-size: 0.72rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 2px;
  font-family: var(--font-mono);
}

.ccard-value {
  font-size: 0.88rem;
  color: var(--text-primary);
  font-weight: 500;
  transition: color var(--transition);
  word-break: break-all;
}

a.ccard-value:hover { color: var(--accent); }

/* Map */
.map-deco {}

.map-svg {
  width: 100%;
  height: auto;
  border-radius: var(--radius);
  border: 1px solid var(--border);
}

/* Contact Form */
.contact-form-wrap {
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
  padding: 36px;
  border: 1px solid var(--border);
}

.contact-form {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.form-group label {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-primary);
  letter-spacing: 0.02em;
}

.form-group input,
.form-group textarea {
  background: var(--bg-primary);
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 12px 16px;
  color: var(--text-white);
  font-size: 0.9rem;
  transition: border-color var(--transition), box-shadow var(--transition);
  outline: none;
  resize: vertical;
}

.form-group input::placeholder,
.form-group textarea::placeholder {
  color: var(--text-secondary);
  opacity: 0.6;
}

.form-group input:focus,
.form-group textarea:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(100, 255, 218, 0.1);
}

.form-group input.error,
.form-group textarea.error {
  border-color: #ff6b6b;
  box-shadow: 0 0 0 3px rgba(255, 107, 107, 0.1);
}

.form-error {
  font-size: 0.78rem;
  color: #ff6b6b;
  min-height: 16px;
  display: block;
}

.btn-icon { width: 18px; height: 18px; }

.form-success {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 14px 18px;
  background: rgba(100, 255, 218, 0.08);
  border: 1px solid rgba(100, 255, 218, 0.3);
  border-radius: var(--radius-sm);
  color: var(--accent);
  font-size: 0.88rem;
  font-weight: 500;
  animation: fadeInUp 0.5s ease;
}

.form-success svg { width: 20px; height: 20px; flex-shrink: 0; }
.form-success.show { display: flex; }

/* =============================================
   FOOTER
   ============================================= */
.footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  padding: 60px 0 32px;
}

.footer-top {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 20px;
  margin-bottom: 36px;
}

.footer-logo {
  font-size: 1.5rem;
}

.footer-tagline {
  color: var(--text-secondary);
  font-size: 0.9rem;
  max-width: 400px;
}

.footer-socials {
  display: flex;
  gap: 16px;
}

.social-link {
  width: 42px;
  height: 42px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  border: 1.5px solid var(--border);
  color: var(--text-secondary);
  transition: var(--transition);
}

.social-link svg { width: 18px; height: 18px; }

.social-link:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: rgba(100, 255, 218, 0.07);
  transform: translateY(-3px);
}

.footer-nav {
  display: flex;
  justify-content: center;
  gap: 32px;
  flex-wrap: wrap;
  margin-bottom: 32px;
}

.footer-nav a {
  font-size: 0.85rem;
  color: var(--text-secondary);
  transition: color var(--transition);
}

.footer-nav a:hover { color: var(--accent); }

.footer-bottom {
  text-align: center;
  padding-top: 24px;
  border-top: 1px solid var(--border);
}

.footer-bottom p {
  font-size: 0.82rem;
  color: var(--text-secondary);
}

/* =============================================
   BACK TO TOP
   ============================================= */
.back-to-top {
  position: fixed;
  bottom: 28px;
  right: 28px;
  width: 44px;
  height: 44px;
  background: rgba(100, 255, 218, 0.15);
  border: 1.5px solid var(--accent);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent);
  opacity: 0;
  pointer-events: none;
  transition: var(--transition);
  z-index: 998;
}

.back-to-top svg { width: 20px; height: 20px; }

.back-to-top.show {
  opacity: 1;
  pointer-events: auto;
}

.back-to-top:hover {
  background: rgba(100, 255, 218, 0.25);
  transform: translateY(-3px);
}

/* =============================================
   RESPONSIVE — TABLET (≤ 900px)
   ============================================= */
@media (max-width: 900px) {
  .hero-container {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .hero-avatar { order: -1; }
  .avatar-svg { max-width: 280px; }
  .hero-desc { margin-left: auto; margin-right: auto; }
  .hero-cta { justify-content: center; }

  .about-grid,
  .contact-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .skills-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .portfolio-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .about-stats { justify-content: center; }
}

/* =============================================
   RESPONSIVE — MOBILE (≤ 600px)
   ============================================= */
@media (max-width: 600px) {
  .section { padding: 72px 0; }
  .section-header { margin-bottom: 44px; }

  /* Mobile Nav */
  .hamburger { display: flex; }

  .nav-links {
    position: fixed;
    top: 0;
    right: -100%;
    width: min(75vw, 300px);
    height: 100dvh;
    background: var(--bg-secondary);
    flex-direction: column;
    justify-content: center;
    gap: 40px;
    padding: 80px 40px;
    border-left: 1px solid var(--border);
    transition: right 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: -20px 0 60px rgba(0,0,0,0.5);
  }

  .nav-links.open { right: 0; }

  .nav-link {
    font-size: 1.1rem;
  }

  /* Overlay */
  .nav-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.6);
    z-index: 998;
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition);
    backdrop-filter: blur(4px);
  }

  .nav-overlay.show {
    opacity: 1;
    pointer-events: auto;
  }

  .hero { padding: calc(var(--navbar-h) + 24px) 24px 60px; }
  .hero-name { font-size: 2.5rem; }
  .avatar-svg { max-width: 240px; }

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

  .about-stats { gap: 16px; }
  .stat-item { padding: 12px 18px; }

  .contact-form-wrap { padding: 24px 20px; }

  .footer-nav { gap: 20px; }

  .back-to-top { bottom: 20px; right: 20px; }

  .hero-cta { flex-direction: column; align-items: center; }
  .hero-cta .btn { width: 100%; max-width: 280px; justify-content: center; }

  .edu-item { flex-direction: column; }

  .btn { padding: 11px 22px; }

  .portfolio-filter { gap: 8px; }
  .filter-btn { padding: 6px 16px; font-size: 0.8rem; }
}

@media (max-width: 380px) {
  .hero-name { font-size: 2rem; }
  .section-title { font-size: 1.6rem; }
}