/* ===== Global Reset & Variables ===== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --clr-primary: #2563eb; /* blue-600 */
  --clr-dark: #0f172a;    /* slate-900 */
  --clr-light: #f8fafc;   /* slate-50 */
  --clr-surface: #ffffff; /* white */
  --clr-muted: #64748b;   /* slate-500 */
  --radius: 0.75rem;
  --shadow: 0 4px 10px rgba(0, 0, 0, 0.05);
}

/* ===== Base Styles ===== */
body {
  font-family: 'Inter', sans-serif;
  line-height: 1.6;
  color: var(--clr-dark);
  background: var(--clr-light);
}

a {
  color: var(--clr-primary);
  text-decoration: none;
  transition: color 0.2s ease-in-out;
}

a:hover {
  text-decoration: underline;
}

.container {
  width: 90%;
  max-width: 1100px;
  margin: 0 auto;
}

/* ===== Header & Navigation ===== */
.site-header {
  background: var(--clr-surface);
  box-shadow: var(--shadow);
  position: sticky;
  top: 0;
  z-index: 100;
}

.site-header .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 0;
}

.logo a {
  font-weight: 800;
  font-size: 1.25rem;
  color: var(--clr-dark);
  display: flex;
  align-items: center;
  gap: 0.5rem;   /* space between logo and text */
}

/* small round logo */
.logo-img {
  height: 32px;
  width: 32px;
  border-radius: 50%;
}
}

/* Desktop nav layout */
.nav {
  display: flex;
  gap: 1.5rem;
}

.nav a {
  font-weight: 600;
  color: var(--clr-dark);
}

.nav a:hover {
  color: var(--clr-primary);
}

/* Mobile hamburger toggle (hidden on desktop) */
.nav-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.75rem;
  line-height: 1;
  cursor: pointer;
  color: var(--clr-dark);
}

/* ===== Hero Section ===== */
.hero {
  padding: 5rem 0;
  text-align: center;
  background: linear-gradient(135deg, #dbeafe 0%, #e0f2fe 100%);
}

.hero h2 {
  font-size: 2rem;
  font-weight: 800;
  margin-bottom: 1rem;
}

.hero p {
  font-size: 1.1rem;
  color: var(--clr-dark);
  margin-bottom: 2rem;
}

.btn {
  display: inline-block;
  background: var(--clr-primary);
  color: #fff;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius);
  font-weight: 600;
  transition: background 0.2s ease-in-out;
}

.btn:hover {
  background: #1d4ed8; /* darker blue */
}

/* ===== Generic Section ===== */
.section {
  padding: 3.5rem 0;
}

.section.alt {
  background: var(--clr-light);
}

.section h3 {
  font-size: 1.75rem;
  font-weight: 800;
  text-align: center;
  margin-bottom: 2rem;
}

/* ===== Project Cards ===== */
.cards {
  display: grid;
  gap: 1.5rem;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

.card {
  background: var(--clr-surface);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.card h4 {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  color: var(--clr-dark);
}

.card p {
  color: var(--clr-muted);
  flex-grow: 1;
  margin-bottom: 1rem;
}

.card a {
  align-self: flex-start;
  font-weight: 600;
}

/* ===== Timeline ===== */
.timeline {
  list-style: none;
}

.timeline li {
  margin-bottom: 1.5rem;
  position: relative;
  padding-left: 1.25rem;
}

/* ---- Contact-form styling ---- */
.contact-form input,
.contact-form textarea {
  width: 100%;
  padding: 0.75rem 1rem;
  margin-bottom: 1rem;
  border: 1px solid var(--clr-muted);
  border-radius: var(--radius);
  font: inherit;
}

.contact-form input:focus,
.contact-form textarea:focus {
  outline: 2px solid var(--clr-primary);
}


.timeline li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.5rem;
  width: 0.6rem;
  height: 0.6rem;
  border-radius: 50%;
  background: var(--clr-primary);
}

.timeline strong {
  display: block;
  color: var(--clr-dark);
  margin-bottom: 0.25rem;
}

.timeline span {
  color: var(--clr-muted);
}

/* ===== Footer ===== */
.site-footer {
  text-align: center;
  padding: 2rem 0;
  font-size: 0.9rem;
  color: var(--clr-muted);
}

/* ===== Responsive Tweaks ===== */
@media (max-width: 600px) {
  /* hide desktop nav, show hamburger */
  .nav {
    display: none;
    flex-direction: column;
    gap: 1rem;
    background: var(--clr-surface);
    position: absolute;
    right: 1rem;
    top: 4rem;
    padding: 1rem 1.5rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
  }

  .nav.open {
    display: flex;
  }

  .nav-toggle {
    display: block;
  }

  .hero h2 {
    font-size: 1.5rem;
  }
}