/* ========== Global Styles ========== */
:root {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --bg: #f8fafc;
  --card-bg: #ffffff;
  --text: #1e293b;
  --text-light: #64748b;
  --border: #e2e8f0;
  --accent: #10b981;
  --shadow: 0 1px 3px rgba(0,0,0,0.1);
  --shadow-lg: 0 10px 40px rgba(0,0,0,0.08);
  --radius: 12px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Noto Sans TC', sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
}

/* ========== Header ========== */
.header {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: white;
  padding: 1rem 2rem;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 10px rgba(37,99,235,0.3);
}
.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.header h1 { font-size: 1.4rem; font-weight: 700; }
.header h1 a { color: white; text-decoration: none; }
.header nav a {
  color: rgba(255,255,255,0.85);
  text-decoration: none;
  margin-left: 1.5rem;
  font-size: 0.95rem;
  transition: color 0.2s;
}
.header nav a:hover { color: white; }

/* ========== Hero (index only) ========== */
.hero {
  text-align: center;
  padding: 4rem 2rem 2rem;
  max-width: 800px;
  margin: 0 auto;
}
.hero h2 {
  font-size: 2.2rem;
  font-weight: 800;
  margin-bottom: 0.8rem;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}
.hero p {
  color: var(--text-light);
  font-size: 1.1rem;
  max-width: 600px;
  margin: 0 auto;
}

/* ========== Tool Grid ========== */
.tool-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
  max-width: 1200px;
  margin: 2rem auto 4rem;
  padding: 0 2rem;
}
.tool-card {
  background: var(--card-bg);
  border-radius: var(--radius);
  padding: 1.8rem;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
  transition: transform 0.2s, box-shadow 0.2s;
  text-decoration: none;
  color: inherit;
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
}
.tool-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}
.tool-icon {
  font-size: 2.5rem;
  line-height: 1;
}
.tool-card h3 {
  font-size: 1.15rem;
  font-weight: 700;
}
.tool-card p {
  color: var(--text-light);
  font-size: 0.9rem;
  line-height: 1.5;
}
.tool-tag {
  display: inline-block;
  background: #eff6ff;
  color: var(--primary);
  padding: 0.2rem 0.6rem;
  border-radius: 20px;
  font-size: 0.75rem;
  font-weight: 600;
  align-self: flex-start;
}

/* ========== Tool Page Layout ========== */
.tool-page {
  max-width: 900px;
  margin: 2rem auto;
  padding: 0 2rem 4rem;
}
.tool-page h2 {
  font-size: 1.8rem;
  margin-bottom: 0.5rem;
}
.tool-page .tool-desc {
  color: var(--text-light);
  margin-bottom: 1.5rem;
}

/* ========== Tool Controls ========== */
.tool-box {
  background: var(--card-bg);
  border-radius: var(--radius);
  padding: 2rem;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
  margin-bottom: 1.5rem;
}
.tool-box label {
  display: block;
  font-weight: 600;
  margin-bottom: 0.4rem;
  font-size: 0.9rem;
}
.tool-box input[type="text"],
.tool-box input[type="number"],
.tool-box input[type="url"],
.tool-box textarea,
.tool-box select {
  width: 100%;
  padding: 0.75rem 1rem;
  border: 2px solid var(--border);
  border-radius: 8px;
  font-size: 1rem;
  font-family: inherit;
  transition: border-color 0.2s;
  background: var(--bg);
}
.tool-box input:focus,
.tool-box textarea:focus,
.tool-box select:focus {
  outline: none;
  border-color: var(--primary);
}
.tool-box textarea {
  min-height: 150px;
  resize: vertical;
  font-family: 'SF Mono', 'Fira Code', monospace;
}
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.7rem 1.5rem;
  background: var(--primary);
  color: white;
  border: none;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.2s;
  font-family: inherit;
}
.btn:hover { background: var(--primary-dark); }
.btn-accent { background: var(--accent); }
.btn-accent:hover { background: #059669; }
.btn-outline {
  background: transparent;
  color: var(--primary);
  border: 2px solid var(--primary);
}
.btn-outline:hover {
  background: var(--primary);
  color: white;
}
.btn-group {
  display: flex;
  gap: 0.8rem;
  flex-wrap: wrap;
  margin-top: 1rem;
}

/* ========== Result Area ========== */
.result-box {
  background: #f1f5f9;
  border-radius: 8px;
  padding: 1.2rem;
  min-height: 60px;
  white-space: pre-wrap;
  word-break: break-all;
  font-family: 'SF Mono', 'Fira Code', monospace;
  font-size: 0.95rem;
  margin-top: 1rem;
  border: 1px dashed var(--border);
}
.result-box.success {
  background: #ecfdf5;
  border-color: #86efac;
}

/* ========== Options Row ========== */
.options-row {
  display: flex;
  gap: 1.5rem;
  flex-wrap: wrap;
  margin-bottom: 1rem;
}
.options-row label {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-weight: 500;
  font-size: 0.9rem;
}
.options-row input[type="checkbox"] {
  width: 18px;
  height: 18px;
  accent-color: var(--primary);
}

/* ========== Footer ========== */
.footer {
  background: var(--text);
  color: rgba(255,255,255,0.7);
  text-align: center;
  padding: 2rem;
  font-size: 0.85rem;
}
.footer a {
  color: rgba(255,255,255,0.9);
  text-decoration: none;
}
.footer a:hover { text-decoration: underline; }

/* ========== Ad Placeholder ========== */
.ad-slot {
  background: #f1f5f9;
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  padding: 1.5rem;
  text-align: center;
  color: var(--text-light);
  font-size: 0.85rem;
  margin: 1.5rem 0;
}
.ad-slot-top {
  min-height: 100px;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* ========== Responsive ========== */
@media (max-width: 640px) {
  .hero h2 { font-size: 1.6rem; }
  .tool-grid { grid-template-columns: 1fr; padding: 0 1rem; }
  .tool-page { padding: 0 1rem 3rem; }
  .tool-box { padding: 1.2rem; }
  .header { padding: 0.8rem 1rem; }
  .header h1 { font-size: 1.1rem; }
}