:root {
  color-scheme: light;
  --bg: #f5f7fb;
  --card: #ffffff;
  --ink: #0f172a;
  --muted: #64748b;
  --border: #e2e8f0;
  --primary: #4f46e5;
  --primary-hover: #4338ca;
  --shadow: 0 12px/ 30px rgba(15, 23, 42, 0.08);
  --shadow-lg: 0 20px 40px rgba(15, 23, 42, 0.1);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Noto Sans TC", "PingFang TC", "Microsoft JhengHei", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background: var(--bg);
  color: var(--ink);
  line-height: 1.6;
}

.container {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 24px;
}

/* Header */
.top-nav {
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
  padding: 16px 0;
  position: sticky;
  top: 0;
  z-index: 10;
}

.top-nav .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.top-nav .brand {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--ink);
  font-weight: 600;
  font-size: 20px;
}

.brand-icon {
  width: 36px;
  height: 36px;
  border-radius: 50%;
}

.top-nav nav {
  display: flex;
  gap: 24px;
}

.top-nav nav a {
  text-decoration: none;
  color: var(--muted);
  font-size: 15px;
  font-weight: 500;
  transition: color 0.2s ease;
}

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

/* Page Layout */
.page {
  max-width: 960px;
  margin: 0 auto;
  padding: 64px 24px;
  display: flex;
  flex-direction: column;
  gap: 48px;
}

/* Hero Section */
.hero {
  text-align: center;
  padding: 32px 0;
}

.hero h1 {
  font-size: 42px;
  margin: 0 0 16px;
  line-height: 1.2;
}

.tagline {
  margin: 0 auto 32px;
  color: var(--muted);
  font-size: 18px;
  max-width: 600px;
}

.cta-button {
  background-color: var(--primary);
  color: white;
  padding: 14px 28px;
  border-radius: 8px;
  text-decoration: none;
  font-weight: 600;
  font-size: 16px;
  transition: background-color 0.2s ease, transform 0.2s ease;
  display: inline-block;
}

.cta-button:hover {
  background-color: var(--primary-hover);
  transform: translateY(-2px);
}

.cta-button.secondary {
  background-color: var(--card);
  color: var(--primary);
  border: 1px solid var(--primary);
}
.cta-button.secondary:hover {
  background-color: #f0f2fe;
}


/* Card */
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 32px;
  box-shadow: var(--shadow);
  text-align: center;
}
section.card {
  text-align: left;
}

.card h2 {
  margin: 0 0 8px;
  text-align: center;
  font-size: 28px;
}
.card p, .card li {
  color: var(--muted);
}
.card ul, .card ol {
    padding-left: 20px;
}
.steps {
    list-style-type: none;
    padding-left: 0;
    counter-reset: step-counter;
}
.steps li {
    position: relative;
    padding-left: 30px;
    margin-bottom: 12px;
}
.steps li::before {
    counter-increment: step-counter;
    content: counter(step-counter);
    position: absolute;
    left: 0;
    top: 0;
    font-weight: bold;
    color: var(--primary);
    background-color: #eef2ff;
    border-radius: 50%;
    width: 22px;
    height: 22px;
    text-align: center;
    line-height: 22px;
    font-size: 12px;
}


.subtitle {
  margin: 0 auto 24px;
  color: var(--muted);
  text-align: center;
  max-width: 600px;
}

/* Features Grid */
.grid {
  margin-top: 24px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 24px;
  text-align: left;
}

.feature {
  background: #f8fafc;
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 24px;
}

.feature h3 {
  margin: 0 0 8px;
  font-size: 18px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.feature p {
  margin: 0;
  font-size: 15px;
  color: var(--muted);
}

/* Footer */
footer {
  text-align: center;
  color: var(--muted);
  font-size: 14px;
  padding: 40px 0;
  border-top: 1px solid var(--border);
  margin-top: 32px;
}


/* Responsive */
@media (max-width: 768px) {
  .hero h1 {
    font-size: 32px;
  }
  .tagline {
    font-size: 16px;
  }
  .top-nav nav {
    display: none; /* Hide nav on mobile for simplicity, can be replaced with a burger menu */
  }
  .page {
    padding: 48px 16px;
    gap: 32px;
  }
}
.pricing-container {
  display: flex;
  gap: 32px;
  margin-top: 32px;
  flex-wrap: wrap;
}
.pricing-table, .usage-rules {
  flex: 1;
  min-width: 280px;
}
.pricing-table h3, .usage-rules h3 {
  text-align: left;
  font-size: 20px;
  margin-bottom: 16px;
  border-bottom: 1px solid var(--border);
  padding-bottom: 8px;
}
table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
}
th, td {
  padding: 12px;
  border-bottom: 1px solid var(--border);
}
th {
  background-color: #f8fafc;
  font-weight: 600;
  color: var(--ink);
}
tbody tr:last-child td {
  border-bottom: none;
}
tbody tr:hover {
  background-color: #f8fafc;
}
.usage-rules ul {
  list-style: none;
  padding: 0;
}
.usage-rules li {
  padding: 10px 0;
  font-size: 16px;
}
.note {
  font-size: 14px;
  margin-top: 16px;
  background-color: #f8fafc;
  padding: 12px;
  border-radius: 8px;
}
.actions {
  text-align: center;
  margin-top: 40px;
  border-top: 1px solid var(--border);
  padding-top: 32px;
}
.actions p {
  margin: 0 0 16px;
  font-size: 18px;
  font-weight: 500;
}
.actions .cta-button {
  margin: 0 8px;
}
/* Language Switcher */
.lang-switcher {
  position: relative;
  margin-left: 24px;
}
#lang-selector {
  -webkit-appearance: none;
  -moz-appearance: none;
  appearance: none;
  background-color: transparent;
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 6px 30px 6px 12px;
  font-size: 14px;
  color: var(--muted);
  cursor: pointer;
  background-image: url('data:image/svg+xml;charset=US-ASCII,%3Csvg%20width%3D%2220%22%20height%3D%2220%22%20fill%3D%22%2364748B%22%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%3E%3Cpath%20d%3D%22M5%208l5%205%205-5H5z%22%2F%3E%3C%2Fsvg%3E');
  background-repeat: no-repeat;
  background-position: right 8px top 50%;
  background-size: 16px;
}
#lang-selector:hover {
  border-color: #cbd5e1;
}

/* Dropdown Menu */
.dropdown {
  position: relative;
  display: inline-block;
}

.dropbtn {
  background-color: transparent;
  color: var(--muted);
  font-size: 15px;
  font-weight: 500;
  border: none;
  cursor: pointer;
}

.dropdown-content {
  display: none;
  position: absolute;
  background-color: #f1f1f1;
  min-width: 160px;
  box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
  z-index: 1;
}

.dropdown-content a {
  color: black;
  padding: 12px 16px;
  text-decoration: none;
  display: block;
}

.dropdown-content a:hover {
  background-color: #ddd;
}

.dropdown:hover .dropdown-content {
  display: block;
}

.dropdown:hover .dropbtn {
  color: var(--primary);
}