* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Poppins', sans-serif;
  scroll-behavior: smooth;
}

:root {
  --bg: #0a0f1f;
  --card: rgba(255,255,255,0.05);
  --text: #ffffff;

  --primary: #3b82f6;
  --secondary: #2563eb;

  --nav-bg: rgba(10,15,30,0.6);
  --hero-gradient: linear-gradient(-45deg, #0a0f1f, #111827, #0a0f1f);
}

body.light {
  --bg: #f8fafc;
  --card: #ffffff;
  --text: #0f172a;

  --primary: #7c3aed;
  --secondary: #6366f1;

  --nav-bg: rgba(255,255,255,0.85);
  --hero-gradient: linear-gradient(-45deg, #eef2ff, #f5f3ff, #e0e7ff);
}

body {
  background: var(--bg);
  color: var(--text);
  transition: 0.4s ease;
  overflow-x: hidden;
}

/* NAVBAR */
nav {
  position: fixed;
  width: 100%;
  padding: 18px 8%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  backdrop-filter: blur(14px);
  background: var(--nav-bg);
  z-index: 1000;
}

.logo {
  font-weight: 700;
  font-size: 1.2rem;
  background: linear-gradient(45deg, var(--primary), var(--secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  cursor: pointer;
}

nav ul {
  list-style: none;
  display: flex;
  gap: 30px;
}

nav ul li a {
  text-decoration: none;
  color: var(--text);
  transition: 0.3s;
}

nav ul li a:hover {
  color: var(--primary);
}

#themeToggle {
  background: none;
  border: none;
  font-size: 20px;
  cursor: pointer;
  color: var(--text);
}

/* HERO */
.hero {
  height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  background: var(--hero-gradient);
  background-size: 300% 300%;
  animation: gradientMove 60s linear infinite;
  text-align: center;
  padding: 0 20px;
}

.hero h1 {
  font-size: 3rem;
}

.hero span {
  background: linear-gradient(45deg, var(--primary), var(--secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.btn {
  margin-top: 30px;
  padding: 12px 40px;
  border-radius: 40px;
  border: none;
  background: linear-gradient(45deg, var(--primary), var(--secondary));
  color: white;
  cursor: pointer;
  transition: 0.3s;
}

.btn:hover {
  transform: translateY(-4px);
}

/* ===============================
   STACK SECTION
================================ */

.stack-container {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(130px, 1fr));
  gap: 30px;
  max-width: 900px;
  margin: auto;
}

.stack-item {
  background: var(--card);
  backdrop-filter: blur(8px);
  padding: 25px;
  border-radius: 20px;
  text-align: center;
  transition: 0.3s ease;
  box-shadow: 0 10px 30px rgba(0,0,0,0.2);
}

.stack-item:hover {
  transform: translateY(-8px);
  box-shadow: 0 20px 50px rgba(0,0,0,0.3);
}

.stack-item ion-icon {
  font-size: 40px;
  margin-bottom: 10px;
  color: var(--primary);
}

.stack-item img {
  width: 40px;
  margin-bottom: 10px;
}

.stack-item span {
  display: block;
  font-weight: 500;
}

.stack-item i {
 font-size: 55px;   /* increase size (was ~40px) */
  margin-bottom: 12px;
  color: var(--primary);
}

.stack-item {
  padding: 15px;
}

/* SECTIONS */
section {
  padding: 110px 8%;
  opacity: 0;
  transform: translateY(50px);
  transition: 0.8s ease;
}

section.active {
  opacity: 1;
  transform: translateY(0);
}

.section-title {
  text-align: center;
  margin-bottom: 60px;
  font-size: 2.2rem;
  background: linear-gradient(45deg, var(--primary), var(--secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* CARDS */
.card-container {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 35px;
}

.card {
  background: var(--card);
  padding: 35px;
  border-radius: 24px;
  transition: 0.4s ease;
  backdrop-filter: blur(8px);
  box-shadow: 0 15px 40px rgba(0,0,0,0.2);
}

.card:hover {
  transform: translateY(-12px);
}

/* SOCIAL FOOTER */
.social-footer {
  display: flex;
  justify-content: center;
  gap: 30px;
  margin-top: 40px;
  flex-wrap: wrap;
}

.social {
  width: 55px;
  height: 55px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--card);
  font-size: 24px;
  color: var(--text);
  transition: all 0.3s ease;
  text-decoration: none;
  box-shadow: 0 10px 25px rgba(0,0,0,0.2);
}

.social:hover {
  transform: translateY(-6px);
  background: linear-gradient(45deg, var(--primary), var(--secondary));
  color: #fff;
}

/* FOOTER */
footer {
  text-align: center;
  padding: 40px;
  opacity: 0.6;
}

/* ===============================
   MOBILE NAVBAR FIX
================================ */

@media (max-width: 768px) {

  nav {
    flex-wrap: wrap;
    padding: 15px 5%;
    gap: 10px;
  }

  /* center menu below logo */
  nav ul {
    width: 100%;
    justify-content: center;
    gap: 18px;
    flex-wrap: wrap;
  }

  /* keep theme button visible */
  #themeToggle {
    position: absolute;
    right: 15px;
    top: 15px;
  }

  /* reduce hero text size for mobile */
  .hero h1 {
    font-size: 2rem;
  }

  .hero h3 {
    font-size: 1.1rem;
  }

  /* reduce section spacing */
  section {
    padding: 80px 5%;
  }
}

/* ===============================
   MOBILE SOCIAL ICON FIX
================================ */

@media (max-width: 768px) {

  .social-footer {
    display: grid;
    grid-template-columns: repeat(3, 1fr); /* equal rows */
    justify-items: center;
    align-items: center;
    max-width: 220px;
    margin: 40px auto 0;
    gap: 18px;
  }

  .social {
    width: 55px;
    height: 55px;
  }
}

/* fix mobile wrapping layout */
@media (max-width: 768px) {
  .social-footer {
    gap: 18px;
  }
}

@keyframes gradientMove {
  0% { background-position: 0% 50%; }
  100% { background-position: 100% 50%; }
}