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

:root {
  --bg: #0b1120;
  --card: #101a30;
  --card2: #16223c;
  --border: #233450;
  --text: #e2e8f0;
  --muted: #8fa3bf;
  --accent: #38bdf8;
  --accent2: #818cf8;
  --green: #34d399;
  --yellow: #fbbf24;
  --red: #f87171;
  --radius: 12px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  background:
    radial-gradient(1200px 500px at 80% -10%, rgba(56, 189, 248, .12), transparent 60%),
    radial-gradient(900px 400px at 10% -10%, rgba(129, 140, 248, .12), transparent 60%),
    var(--bg);
  color: var(--text);
  min-height: 100vh;
}

header { padding: 40px 20px 16px; text-align: center; }
.logo {
  font-size: 28px; font-weight: 800;
  background: linear-gradient(90deg, var(--accent), var(--accent2));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.subtitle { color: var(--muted); margin-top: 6px; font-size: 14px; }

.tabs { display: flex; justify-content: center; gap: 8px; flex-wrap: wrap; padding: 10px 20px 0; }
.tab {
  background: var(--card); color: var(--muted); border: 1px solid var(--border);
  padding: 8px 16px; border-radius: 999px; cursor: pointer; font-size: 14px; transition: .2s;
}
.tab:hover { color: var(--text); border-color: var(--accent); }
.tab.active {
  background: linear-gradient(90deg, rgba(56,189,248,.18), rgba(129,140,248,.18));
  color: var(--accent); border-color: var(--accent); font-weight: 600;
}

main { max-width: 860px; margin: 0 auto; padding: 24px 20px 60px; }
.panel {
  display: none; background: var(--card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 24px; animation: fade .25s;
}
.panel.active { display: block; }
@keyframes fade { from { opacity: 0; transform: translateY(6px); } to { opacity: 1; transform: none; } }

h2 { font-size: 18px; margin-bottom: 6px; }
.hint { color: var(--muted); font-size: 13px; margin-bottom: 16px; line-height: 1.7; }
.hint b { color: var(--text); }

.row { display: flex; gap: 10px; flex-wrap: wrap; align-items: center; }
.form-row { margin-bottom: 14px; }

input, select {
  background: var(--card2); border: 1px solid var(--border); color: var(--text);
  padding: 9px 12px; border-radius: 8px; font-size: 14px; outline: none; transition: .2s;
}
input:focus, select:focus { border-color: var(--accent); }
input[type="text"] { flex: 1; min-width: 180px; }
input[type="number"] { width: 100px; }
select { cursor: pointer; }

.btn {
  background: linear-gradient(90deg, var(--accent), var(--accent2));
  color: #06121f; border: none; padding: 10px 20px; border-radius: 8px;
  font-size: 14px; font-weight: 700; cursor: pointer; transition: .2s;
}
.btn:hover { filter: brightness(1.1); transform: translateY(-1px); }
.btn:disabled { opacity: .5; cursor: not-allowed; transform: none; }
.btn.small { padding: 6px 12px; font-size: 12px; font-weight: 600; }

.quick-row { display: flex; gap: 8px; flex-wrap: wrap; align-items: center; margin-bottom: 16px; }
.quick-label { color: var(--muted); font-size: 13px; }

.log {
  margin-top: 16px; background: #0a1122; border: 1px solid var(--border); border-radius: 8px;
  padding: 12px; font-family: "SFMono-Regular", Consolas, "Courier New", monospace;
  font-size: 13px; line-height: 1.9; max-height: 320px; overflow-y: auto; word-break: break-all;
}
.log-line.good { color: var(--green); }
.log-line.ok { color: #a7f3d0; }
.log-line.warn { color: var(--yellow); }
.log-line.bad { color: var(--red); }
.log-line.muted { color: var(--muted); }

#ping-stats { margin-top: 12px; font-size: 14px; color: var(--muted); }

.stun-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 12px; margin: 16px 0; }
.stun-card { background: var(--card2); border: 1px solid var(--border); border-radius: 10px; padding: 14px; }
.stun-name { font-weight: 600; font-size: 14px; }
.stun-url { color: var(--muted); font-size: 12px; margin: 4px 0 10px; word-break: break-all; }
.stun-result { font-size: 13px; margin-bottom: 10px; }
.stun-result.testing { color: var(--muted); }
.stun-result.good { color: var(--green); }
.stun-result.ok { color: #a7f3d0; }
.stun-result.warn { color: var(--yellow); }
.stun-result.bad { color: var(--red); }

#http-presets { display: flex; gap: 8px; flex-wrap: wrap; margin: 12px 0; }

.bar-track {
  background: var(--card2); border: 1px solid var(--border); border-radius: 999px;
  height: 14px; overflow: hidden; margin: 16px 0 8px;
}
.bar-fill {
  height: 100%; width: 0;
  background: linear-gradient(90deg, var(--accent), var(--accent2));
  transition: width .25s;
}
.speed-stats { font-size: 13px; color: var(--muted); min-height: 18px; }
.hidden { display: none; }

footer { text-align: center; color: var(--muted); font-size: 12px; padding: 20px; line-height: 1.8; }