/* Shared styles for all tool pages */
:root{
  --bg:#0a0e17;--surface:#111827;--surface2:#1a2332;
  --border:#1e293b;--border-glow:rgba(99,102,241,0.15);
  --text:#f1f5f9;--text2:#94a3b8;--text3:#64748b;
  --accent:#818cf8;--accent2:#6366f1;
  --green:#22c55e;--red:#ef4444;--yellow:#fbbf24;--blue:#38bdf8;
  --gradient:linear-gradient(135deg,#667eea 0%,#764ba2 100%);
  --shadow:0 4px 24px rgba(0,0,0,0.3);
  --glow:0 0 40px rgba(99,102,241,0.08);
}
*{margin:0;padding:0;box-sizing:border-box}
body{font-family:'Inter','Noto Sans TC',system-ui,-apple-system,sans-serif;background:var(--bg);color:var(--text);min-height:100vh;line-height:1.6;-webkit-font-smoothing:antialiased;overflow-x:hidden}
a{text-decoration:none;color:var(--accent)}
a:hover{color:#a5b4fc}

/* Animated background */
.bg-mesh{position:fixed;inset:0;z-index:0;overflow:hidden;pointer-events:none}
.bg-mesh::before{content:'';position:absolute;width:600px;height:600px;top:-200px;right:-200px;background:radial-gradient(circle,rgba(99,102,241,0.06) 0%,transparent 70%);animation:bgFloat 20s ease-in-out infinite}
.bg-mesh::after{content:'';position:absolute;width:500px;height:500px;bottom:-150px;left:-150px;background:radial-gradient(circle,rgba(168,85,247,0.04) 0%,transparent 70%);animation:bgFloat 25s ease-in-out infinite reverse}
@keyframes bgFloat{0%,100%{transform:translate(0,0)}50%{transform:translate(30px,20px)}}

.container{max-width:640px;margin:0 auto;padding:20px 16px;position:relative;z-index:1}
.back-link{display:inline-flex;align-items:center;gap:6px;font-size:0.88rem;margin-bottom:16px;color:var(--text3);padding:6px 0;transition:all .2s}
.back-link:hover{color:var(--accent);transform:translateX(-3px)}
header{text-align:center;padding:24px 0 20px;animation:fadeIn .4s ease}
header h1{font-size:1.6rem;font-weight:700;color:var(--text);margin-bottom:6px}
header p{color:var(--text3);font-size:0.9rem}
.ad-slot{background:var(--surface);border:1px dashed var(--border);border-radius:12px;padding:20px;text-align:center;color:var(--text3);font-size:0.8rem;margin:20px 0}

/* Cards with hover glow */
.card{background:var(--surface);border-radius:16px;padding:24px;border:1px solid var(--border);margin:20px 0;transition:all .25s;box-shadow:var(--shadow);animation:fadeIn .4s ease}
.card:hover{border-color:var(--border-glow);box-shadow:var(--glow),var(--shadow)}
@keyframes fadeIn{from{opacity:0;transform:translateY(12px)}to{opacity:1;transform:none}}

label{display:block;font-size:0.85rem;color:var(--text2);margin-bottom:6px;font-weight:500}
.input-group{margin-bottom:18px}
input[type="number"],input[type="text"],input[type="date"],input[type="datetime-local"],select{
  width:100%;padding:12px 14px;border:1px solid var(--border);border-radius:10px;
  background:var(--surface2);color:var(--text);font-size:1rem;font-family:inherit;
  outline:none;transition:all .2s
}
input:focus,select:focus{border-color:var(--accent2);box-shadow:0 0 0 3px rgba(99,102,241,0.12)}
input[type="number"]::-webkit-inner-spin-button{-webkit-appearance:none}
input[type="number"]{-moz-appearance:textfield}

/* Buttons with improved feedback */
.btn{
  width:100%;padding:14px;border:none;border-radius:12px;
  font-size:1rem;font-weight:600;cursor:pointer;font-family:inherit;
  transition:all .2s
}
.btn-primary{background:var(--gradient);color:#fff;box-shadow:0 2px 12px rgba(102,126,234,0.2)}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 6px 24px rgba(102,126,234,0.35)}
.btn-primary:active{transform:translateY(0);box-shadow:0 2px 8px rgba(102,126,234,0.2)}
.btn-secondary{background:var(--surface2);color:var(--accent);border:1px solid var(--border)}
.btn-secondary:hover{background:var(--border);color:var(--text);border-color:var(--border-glow)}

/* Result box with accent glow */
.result-box{background:var(--surface2);border-radius:12px;padding:18px;text-align:center;margin-top:10px;border:1px solid var(--border);transition:all .3s}
.result-box.has-result{border-color:rgba(129,140,248,0.2);box-shadow:0 0 20px rgba(129,140,248,0.06)}
.result-box .amount{font-size:1.8rem;font-weight:700;color:var(--accent);word-break:break-all}
.result-box .info{font-size:0.85rem;color:var(--text2);margin-top:8px}

/* Site nav in tool pages */
.site-nav{display:flex;gap:10px;justify-content:center;flex-wrap:wrap;margin:8px 0}
.site-nav a{display:inline-flex;align-items:center;gap:6px;padding:8px 16px;background:var(--surface);border:1px solid var(--border);border-radius:10px;color:var(--text2);font-size:0.85rem;font-weight:500;transition:all .2s}
.site-nav a:hover{border-color:rgba(129,140,248,0.3);color:var(--text);background:var(--surface2)}

footer{text-align:center;padding:32px 0 20px;color:var(--text3);font-size:0.8rem}
footer a{color:var(--accent)}
footer a:hover{text-decoration:underline}

/* Responsive */
@media(max-width:480px){
  header h1{font-size:1.35rem}
  .container{padding:16px 12px}
  .card{padding:20px 16px}
  .result-box .amount{font-size:1.4rem}
}