:root {
  --blue-dark: #0f2d5e;
  --blue-mid: #0078d4;
  --blue-light: #e8f4fd;
  --accent: #50e6ff;
  --text-dark: #1a1a2e;
  --text-mid: #444;
  --text-light: #666;
  --card-bg: #ffffff;
  --bg: #f5f9ff;
  --radius: 14px;
}

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

body {
  font-family: "Segoe UI", system-ui, sans-serif;
  background: var(--bg);
  color: var(--text-dark);
  line-height: 1.6;
}

/* ── NAV ── */
nav {
  position: fixed; top: 0; width: 100%; z-index: 100;
  background: rgba(15,45,94,0.92);
  backdrop-filter: blur(12px);
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 5%; height: 60px;
}
.nav-logo { color: white; font-size: 1.1rem; font-weight: 700; letter-spacing: 0.5px; }
.nav-links { display: flex; gap: 28px; list-style: none; }
.nav-links a { color: rgba(255,255,255,0.85); text-decoration: none; font-size: 0.9rem; transition: color .2s; }
.nav-links a:hover { color: var(--accent); }

/* ── LANGUAGE SWITCHER ── */
.lang-switcher { display: flex; gap: 6px; align-items: center; }
.lang-btn {
  padding: 4px 12px; border-radius: 20px;
  border: 1px solid rgba(255,255,255,0.35);
  background: transparent; color: rgba(255,255,255,0.7);
  font-size: 0.8rem; cursor: pointer; transition: all .2s; font-weight: 600;
}
.lang-btn.active,
.lang-btn:hover { background: var(--accent); color: var(--blue-dark); border-color: var(--accent); }

/* ── HERO ── */
.hero {
  background: linear-gradient(135deg, #0f2d5e 0%, #0078d4 60%, #50e6ff 100%);
  min-height: 100vh; display: flex; align-items: center; justify-content: center;
  text-align: center; padding: 100px 20px 60px; position: relative; overflow: hidden;
}
.hero::before {
  content: ""; position: absolute; inset: 0;
  background: radial-gradient(ellipse at 70% 40%, rgba(80,230,255,0.18) 0%, transparent 60%);
}
.hero-content { position: relative; z-index: 1; max-width: 720px; }
.hero-badge {
  display: inline-block; background: rgba(255,255,255,0.15);
  border: 1px solid rgba(255,255,255,0.3); color: white;
  font-size: 0.8rem; font-weight: 600; padding: 5px 16px;
  border-radius: 20px; margin-bottom: 20px; letter-spacing: 1px; text-transform: uppercase;
}
.hero h1 { color: white; font-size: clamp(2rem,5vw,3.2rem); font-weight: 700; line-height: 1.15; margin-bottom: 12px; }
.hero h1 span { color: var(--accent); }
.hero p { color: rgba(255,255,255,0.88); font-size: 1.1rem; max-width: 580px; margin: 0 auto 32px; }
.hero-cta { display: inline-flex; gap: 14px; flex-wrap: wrap; justify-content: center; }

.btn { padding: 12px 28px; border-radius: 8px; font-size: 0.95rem; font-weight: 600; text-decoration: none; transition: all .2s; cursor: pointer; border: none; }
.btn-primary { background: white; color: var(--blue-mid); }
.btn-primary:hover { background: var(--accent); color: var(--blue-dark); transform: translateY(-2px); }
.btn-outline { background: transparent; color: white; border: 2px solid rgba(255,255,255,0.6); }
.btn-outline:hover { background: rgba(255,255,255,0.1); transform: translateY(-2px); }

.hero-stats { display: flex; justify-content: center; gap: 40px; margin-top: 50px; flex-wrap: wrap; }
.stat { text-align: center; }
.stat-num { font-size: 2rem; font-weight: 700; color: var(--accent); }
.stat-label { font-size: 0.8rem; color: rgba(255,255,255,0.75); text-transform: uppercase; letter-spacing: 0.5px; }

/* ── SECTIONS ── */
section { padding: 80px 5%; }
.section-header { text-align: center; margin-bottom: 50px; }
.section-tag { display: inline-block; background: var(--blue-light); color: var(--blue-mid); font-size: 0.78rem; font-weight: 700; padding: 4px 14px; border-radius: 20px; margin-bottom: 10px; text-transform: uppercase; letter-spacing: 1px; }
.section-header h2 { font-size: clamp(1.6rem,3vw,2.2rem); color: var(--blue-dark); margin-bottom: 10px; }
.section-header p { color: var(--text-light); max-width: 520px; margin: 0 auto; }

/* ── ABOUT ── */
.about-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 50px; align-items: center; max-width: 1100px; margin: 0 auto; }
.about-text h3 { font-size: 1.5rem; color: var(--blue-dark); margin-bottom: 14px; }
.about-text p { color: var(--text-mid); margin-bottom: 16px; }
.about-info-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin-top: 24px; }
.info-item { display: flex; flex-direction: column; }
.info-label { font-size: 0.75rem; color: var(--text-light); text-transform: uppercase; letter-spacing: 0.5px; }
.info-value { font-size: 0.95rem; font-weight: 600; color: var(--blue-dark); }
.about-affiliations { background: var(--blue-dark); color: white; border-radius: var(--radius); padding: 28px; }
.about-affiliations h4 { color: var(--accent); font-size: 0.85rem; text-transform: uppercase; letter-spacing: 1px; margin-bottom: 16px; }
.affil-item { display: flex; align-items: flex-start; gap: 10px; margin-bottom: 12px; font-size: 0.9rem; color: rgba(255,255,255,0.88); }
.affil-dot { width: 8px; height: 8px; background: var(--accent); border-radius: 50%; margin-top: 7px; flex-shrink: 0; }
.interest-tag { background: rgba(255,255,255,0.12); border-radius: 20px; padding: 4px 14px; font-size: 0.85rem; }

/* ── EXPERIENCE ── */
#experience { background: white; }
.timeline { max-width: 900px; margin: 0 auto; position: relative; }
.timeline::before { content: ""; position: absolute; left: 28px; top: 0; bottom: 0; width: 2px; background: linear-gradient(to bottom, var(--blue-mid), var(--accent)); }
.timeline-item { display: flex; gap: 30px; margin-bottom: 36px; position: relative; }
.timeline-dot { width: 58px; height: 58px; border-radius: 50%; background: linear-gradient(135deg, var(--blue-mid), var(--accent)); display: flex; align-items: center; justify-content: center; color: white; font-size: 1.4rem; flex-shrink: 0; z-index: 1; box-shadow: 0 4px 16px rgba(0,120,212,0.3); }
.timeline-card { background: var(--card-bg); border-radius: var(--radius); padding: 24px; flex: 1; box-shadow: 0 2px 20px rgba(0,0,0,0.07); border: 1px solid #e8eef6; transition: transform .2s, box-shadow .2s; }
.timeline-card:hover { transform: translateY(-3px); box-shadow: 0 8px 30px rgba(0,120,212,0.12); }
.timeline-card-header { display: flex; justify-content: space-between; align-items: flex-start; flex-wrap: wrap; gap: 8px; margin-bottom: 8px; }
.job-title { font-size: 1.05rem; font-weight: 700; color: var(--blue-dark); }
.job-period { background: var(--blue-light); color: var(--blue-mid); font-size: 0.78rem; font-weight: 600; padding: 3px 12px; border-radius: 20px; }
.company { font-size: 0.88rem; color: var(--blue-mid); font-weight: 600; margin-bottom: 10px; }
.job-desc { font-size: 0.88rem; color: var(--text-mid); margin-bottom: 12px; }
.achievements { list-style: none; }
.achievements li { font-size: 0.85rem; color: var(--text-mid); padding: 4px 0 4px 18px; position: relative; }
.achievements li::before { content: "✓"; position: absolute; left: 0; color: var(--blue-mid); font-weight: 700; }

/* ── SKILLS ── */
.skills-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px,1fr)); gap: 20px; max-width: 1100px; margin: 0 auto; }
.skill-card { background: white; border-radius: var(--radius); padding: 24px; box-shadow: 0 2px 16px rgba(0,0,0,0.06); border: 1px solid #e8eef6; transition: transform .2s, box-shadow .2s; }
.skill-card:hover { transform: translateY(-4px); box-shadow: 0 8px 30px rgba(0,120,212,0.12); }
.skill-icon { font-size: 2rem; margin-bottom: 12px; }
.skill-card h4 { font-size: 0.95rem; font-weight: 700; color: var(--blue-dark); margin-bottom: 10px; }
.skill-tags { display: flex; flex-wrap: wrap; gap: 6px; }
.tag { background: var(--blue-light); color: var(--blue-mid); font-size: 0.75rem; padding: 3px 10px; border-radius: 20px; font-weight: 500; }

/* ── COMPETENCIES ── */
#competencies { background: white; }
.comp-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px,1fr)); gap: 16px; max-width: 1100px; margin: 0 auto; }
.comp-item { background: var(--bg); border-radius: 10px; padding: 18px 16px; border-left: 4px solid var(--blue-mid); font-size: 0.88rem; font-weight: 600; color: var(--blue-dark); transition: background .2s, transform .2s; }
.comp-item:hover { background: var(--blue-light); transform: translateX(4px); }

/* ── CERTIFICATIONS ── */
.certs-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px,1fr)); gap: 20px; max-width: 1000px; margin: 0 auto; }
.cert-card { background: white; border-radius: var(--radius); padding: 24px; box-shadow: 0 2px 16px rgba(0,0,0,0.06); border: 1px solid #e8eef6; display: flex; align-items: flex-start; gap: 16px; transition: transform .2s; }
.cert-card:hover { transform: translateY(-3px); }
.cert-icon { width: 44px; height: 44px; background: linear-gradient(135deg, var(--blue-mid), var(--accent)); border-radius: 10px; display: flex; align-items: center; justify-content: center; color: white; font-size: 1.2rem; flex-shrink: 0; }
.cert-info h4 { font-size: 0.92rem; font-weight: 700; color: var(--blue-dark); margin-bottom: 4px; }
.cert-info p { font-size: 0.8rem; color: var(--text-light); }

/* ── EDUCATION ── */
#education { background: white; }
.edu-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px,1fr)); gap: 20px; max-width: 1000px; margin: 0 auto; }
.edu-card { background: var(--bg); border-radius: var(--radius); padding: 26px; border: 1px solid #e8eef6; transition: transform .2s; position: relative; overflow: hidden; }
.edu-card::before { content: ""; position: absolute; top: 0; left: 0; right: 0; height: 4px; background: linear-gradient(90deg, var(--blue-mid), var(--accent)); }
.edu-card:hover { transform: translateY(-3px); }
.edu-year { font-size: 0.78rem; font-weight: 700; color: var(--blue-mid); text-transform: uppercase; letter-spacing: 1px; margin-bottom: 8px; }
.edu-card h4 { font-size: 1rem; font-weight: 700; color: var(--blue-dark); margin-bottom: 6px; }
.edu-card p { font-size: 0.85rem; color: var(--text-mid); }

/* ── CONTACT ── */
#contact { background: linear-gradient(135deg, #0f2d5e 0%, #0078d4 100%); text-align: center; color: white; }
#contact .section-header h2 { color: white; }
#contact .section-header p { color: rgba(255,255,255,0.78); }
.contact-wrapper { display: flex; gap: 40px; flex-wrap: wrap; justify-content: center; align-items: flex-start; max-width: 900px; margin: 0 auto; }
.contact-card { background: rgba(255,255,255,0.1); border: 1px solid rgba(255,255,255,0.2); border-radius: var(--radius); padding: 20px 28px; color: white; text-decoration: none; text-align: center; min-width: 180px; transition: background .2s, transform .2s; display: flex; flex-direction: column; align-items: center; }
.contact-card:hover { background: rgba(255,255,255,0.2); transform: translateY(-3px); }
.contact-card .cicon { font-size: 1.8rem; margin-bottom: 8px; }
.contact-card span { display: block; font-size: 0.8rem; color: rgba(255,255,255,0.7); margin-bottom: 4px; text-transform: uppercase; letter-spacing: 0.5px; }
.contact-card strong { font-size: 0.9rem; }

/* ── CONTACT FORM ── */
.contact-form {
  flex: 1; min-width: 300px;
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.2);
  border-radius: 16px; padding: 32px;
  display: flex; flex-direction: column; gap: 16px;
  text-align: left;
}
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.form-group { display: flex; flex-direction: column; gap: 6px; }
.form-group label { font-size: 0.78rem; color: rgba(255,255,255,0.6); text-transform: uppercase; letter-spacing: 0.5px; }
.form-group input,
.form-group textarea {
  background: rgba(255,255,255,0.1);
  border: 1px solid rgba(255,255,255,0.2);
  border-radius: 8px; padding: 10px 14px;
  color: white; font-size: 0.9rem; outline: none;
  transition: border .2s; font-family: inherit;
}
.form-group input:focus,
.form-group textarea:focus { border-color: #50e6ff; }
.form-group textarea { resize: vertical; }
.btn-send {
  background: white; color: #0078d4; border: none; border-radius: 8px;
  padding: 13px 28px; font-size: 0.95rem; font-weight: 700;
  cursor: pointer; transition: all .2s; align-self: flex-start;
}
.btn-send:hover { background: #50e6ff; color: #0f2d5e; }
.form-status {
  display: none; padding: 10px 16px; border-radius: 8px;
  font-size: 0.88rem; font-weight: 600;
  background: rgba(80,230,255,0.15); color: #50e6ff;
  border: 1px solid rgba(80,230,255,0.3);
}

/* ── FOOTER ── */
footer { background: var(--blue-dark); text-align: center; padding: 20px; font-size: 0.82rem; color: rgba(255,255,255,0.5); }

/* ── PROFILE PHOTO ── */
.about-profile { margin-bottom: 20px; }
.profile-photo {
  width: 110px; height: 110px; border-radius: 50%;
  object-fit: cover;
  border: 3px solid var(--blue-mid);
  box-shadow: 0 4px 16px rgba(0,120,212,0.2);
  display: block;
}

/* ── CERT YEAR BADGE ── */
.cert-year {
  display: inline-block; margin-top: 6px;
  font-size: 0.75rem; font-weight: 700;
  color: var(--blue-mid); background: var(--blue-light);
  padding: 2px 10px; border-radius: 20px;
}

/* ── HAMBURGER TOGGLE ── */
.nav-toggle {
  display: none;
  flex-direction: column; justify-content: space-between;
  width: 26px; height: 18px;
  background: none; border: none; cursor: pointer; padding: 0;
}
.nav-toggle span {
  display: block; width: 100%; height: 2px;
  background: white; border-radius: 2px;
  transition: transform .25s, opacity .25s;
}
.nav-toggle.open span:nth-child(1) { transform: translateY(8px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: translateY(-8px) rotate(-45deg); }

/* ── RESPONSIVE – tablet ── */
@media (max-width: 1024px) {
  .about-grid { gap: 30px; }
  .skills-grid { grid-template-columns: repeat(auto-fit, minmax(200px,1fr)); }
}

/* ── RESPONSIVE – mobile ── */
@media (max-width: 768px) {
  /* Nav */
  .nav-toggle { display: flex; }
  .nav-links {
    display: none;
    position: absolute; top: 60px; left: 0; right: 0;
    flex-direction: column; gap: 0;
    background: rgba(15,45,94,0.97);
    backdrop-filter: blur(12px);
    padding: 12px 0; z-index: 99;
  }
  .nav-links.open { display: flex; }
  .nav-links li { border-bottom: 1px solid rgba(255,255,255,0.07); }
  .nav-links a { display: block; padding: 12px 24px; font-size: 1rem; }
  .lang-switcher { gap: 4px; }
  .lang-btn { padding: 3px 8px; font-size: 0.72rem; }

  /* Layout */
  .about-grid { grid-template-columns: 1fr; }
  .timeline::before { display: none; }
  .form-row { grid-template-columns: 1fr; }
  section { padding: 60px 5%; }

  /* Hero */
  .hero-stats { gap: 24px; }
  .hero-cta { flex-direction: column; align-items: center; }
  .btn { width: 220px; text-align: center; }

  /* Timeline */
  .timeline-item { gap: 16px; }
  .timeline-dot { width: 44px; height: 44px; font-size: 1.1rem; }
}

/* ── RESPONSIVE – small phones ── */
@media (max-width: 420px) {
  .nav-logo { font-size: 0.85rem; }
  .hero h1 { font-size: 1.8rem; }
  .stat-num { font-size: 1.6rem; }
  .comp-grid { grid-template-columns: 1fr; }
  .certs-grid { grid-template-columns: 1fr; }
  .edu-grid   { grid-template-columns: 1fr; }
}