:root {
  --bg: #f7f8fb;
  --card: #ffffff;
  --accent: #0f62fe;
  --muted: #6b7280;
  --maxw: 1000px;
  --radius: 10px;
  font-family: 'Inter', system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial;
}

* {
  box-sizing: border-box;
}

/* keep space for fixed header */
body {
  margin: 0;
  padding-top: 64px; /* adjust if you change header height */
}

/* layout container */
.container {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 24px;
}

/* -------------------------
   HEADER (Fixed)
   ------------------------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background: var(--accent);
  color: #fff;
  box-shadow: 0 2px 6px rgba(0,0,0,0.12);
  z-index: 1000;
  padding: 10px 0;
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

/* brand */
.site-header .brand {
  color: #fff;
  text-decoration: none;
  font-weight: 700;
}

/* main nav (desktop default) */
#main-nav {
  display: flex;
  align-items: center;
  gap: 14px;
}

#main-nav a {
  color: #fff;
  text-decoration: none;
  font-weight: 500;
  padding: 6px 8px;
  border-radius: 6px;
}

#main-nav a:hover {
  background: rgba(255,255,255,0.06);
}

/* header Download CV button — desktop */
.site-header .header-cv-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border-radius: 8px;
  background: #022bf6;
  color: var(--accent); 
  border: none;
  text-decoration: none;
  font-weight: 600;
  font-size: 0.95rem;
  min-width: 110px;
  justify-content: center;
  box-shadow: 0 2px 8px rgba(2,6,23,0.08);
  transition: background 0.2s ease;
}

.site-header .header-cv-btn:hover {
  background: #0043ce;
  color: #fff;
}

/* -------------------------
   GENERIC BUTTON
   ------------------------- */
.btn {
  display: inline-block;
  padding: 8px 12px;
  border-radius: 8px;
  border: 1px solid #ddd;
  text-decoration: none;
}

.btn.primary {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

/* -------------------------
   HERO / MAIN LAYOUT
   ------------------------- */
.hero {
  padding: 40px 0;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 24px;
  align-items: center;
}

.profile-card {
  background: var(--card);
  padding: 18px;
  border-radius: var(--radius);
  box-shadow: 0 6px 18px rgba(12,24,40,0.06);
}

.profile-card img {
  width: 100%;
  border-radius: 8px;
  object-fit: cover;
}

.subtitle {
  color: var(--muted);
  font-weight: 600;
}

.section {
  padding: 40px 0;
}

.section.alt {
  background: #fff;
}

.skills-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
}

.projects-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
}

.project-card, .job {
  background: var(--card);
  padding: 16px;
  border-radius: 8px;
  box-shadow: 0 4px 10px rgba(12,24,40,0.04);
}

.muted {
  color: var(--muted);
  font-size: 0.95rem;
}

.cta-row {
  margin-top: 12px;
}

footer.site-footer {
  padding: 20px 0;
  text-align: center;
  color: var(--muted);
  font-size: 0.9rem;
}

/* -------------------------
   RESPONSIVE (Tablet + Mobile)
   ------------------------- */
@media (max-width: 900px) {
  .hero-grid { grid-template-columns: 1fr; }
  .skills-grid { grid-template-columns: 1fr 1fr; }
  .projects-grid { grid-template-columns: 1fr; }
}

/* MOBILE NAVIGATION */
@media (max-width: 640px) {
  #nav-toggle {
    display: inline-block;
    background: none;
    border: 0;
    font-size: 1.25rem;
    color: #fff;
    cursor: pointer;
  }

  #main-nav {
    display: none;
    position: absolute;
    right: 16px;
    top: 64px;
    background: var(--card);
    padding: 12px;
    border-radius: 8px;
    box-shadow: 0 10px 30px rgba(2,6,23,0.08);
    flex-direction: column;
    gap: 8px;
    min-width: 200px;
    z-index: 1100;
    align-items: flex-start;
    text-align: left;
  }

  #main-nav a {
    color: #0b1220;
    display: block;
    margin: 6px 0;
    width: 100%;
    text-align: left;
  }

  /* When active (menu open) */
  #main-nav.active {
    display: flex;
  }

  /* Mobile version of Download CV button (white) */
  #main-nav .header-cv-btn {
    background: #ffffff !important;
    color: #0f62fe !important;
    align-self: flex-start;
    font-weight: 700;
    border: none;
    box-shadow: 0 2px 8px rgba(2,6,23,0.08);
  }
}

/* -------------------------
   CERTIFICATION SECTION
   ------------------------- */
.certification {
  padding: 60px 0;
  background: var(--bg);
  text-align: center;
}

.certification-grid {
  display: flex;
  justify-content: center;
  align-items: center;
  flex-wrap: wrap;
  gap: 20px;
}

.certification-card {
  max-width: 800px;
  width: 100%;
  margin: 0 auto;
}

.certification-card h4 {
  margin-bottom: 16px;
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--accent);
}

.certification-card img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: 12px;
  margin: 0 auto;
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
}

/* -------------------------
   PROJECT IMAGES
   ------------------------- */
.project-card img {
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.project-card img:hover {
  transform: scale(1.03);
  box-shadow: 0 8px 20px rgba(0,0,0,0.15);
}

/* -------------------------
   TEXT
   ------------------------- */
p {
  text-align: justify;
  text-justify: inter-word;
  max-width: 900px;
  margin-left: auto;
  margin-right: auto;
}

/* -------------------------
   PDF VIEWER
   ------------------------- */
.pdf-viewer {
  width: 100%;
  max-width: 1400px;
  height: 700px;
  border: none;
  display: block;
  margin: 0 auto;
}