:root {
  --primary: #00a8f0;
  --bg: #1b212c;
  --card: #111;
  --card-2: #555;
  --text: #ffffff;
  --muted: #9ca3af;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Segoe UI", Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  opacity: 0;
  animation: fadeIn 1s ease forwards;
}

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

a {
  text-decoration: none;
  color: inherit;
}

/* 圖片全域防爆設定 */
img {
  max-width: 100%;
  height: auto;
  display: block;
}

header {
  position: sticky;
  top: 0;
  background: rgba(27, 33, 44, 0.7);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid #2a2f3a;
  z-index: 100;
  transition: 0.3s;
}

.nav {
  max-width: 1100px;
  margin: auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 30px 20px;
}

.logo {
  font-size: 30px;
  font-weight: bold;
  color: var(--primary);
}

.nav-links { display: flex; gap: 20px; }
.nav-links a:hover { color: var(--primary); }

/* Hero Section */
.hero {
  text-align: center;
  padding: 120px 20px 80px;
  background: radial-gradient(circle at top, rgba(0,168,240,0.15), transparent 60%);
}

.hero img {
  width: 160px;
  margin: 0 auto 20px;
}

.hero h1 { font-size: 48px; }
.typing { color: var(--primary); }
.hero p { color: var(--muted); }

.btn {
  display: inline-block;
  padding: 12px 26px;
  background: var(--primary);
  border-radius: 999px;
  font-weight: bold;
  transition: 0.3s;
}

.btn:hover {
  transform: scale(1.05);
  box-shadow: 0 0 20px rgba(0,168,240,0.4);
}

/* Section Layout */
section {
  max-width: 1100px;
  margin: auto;
  padding: 20px 20px;
}

h2 {
  font-size: 28px;
  margin-bottom: 25px;
  border-left: 4px solid var(--primary);
  padding-left: 10px;
}

@media (max-width: 768px) {
  .hero h1 { font-size: 34px; }
  .grid {
    grid-template-columns: 1fr; /* 手機版單欄顯示 */
  }
}