/* minimal — black background, white text, nothing else */
* { margin: 0; padding: 0; box-sizing: border-box; }

body {
  min-height: 100vh;
  background: #000;
  color: #fff;
  font-family: Arial, Helvetica, sans-serif;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
}

h1 {
  font-size: clamp(40px, 5vw, 72px);
  font-weight: bold;
}

.sub {
  color: #999;
  font-size: clamp(16px, 1.6vw, 24px);
  margin: 10px 0 70px;
}

/* the button */
.ping-btn {
  width: clamp(190px, 18vw, 260px);
  height: clamp(190px, 18vw, 260px);
  border-radius: 50%;
  border: 3px solid #fff;
  background: transparent;
  color: #fff;
  font-family: inherit;
  font-size: clamp(20px, 2vw, 28px);
  letter-spacing: 3px;
  cursor: pointer;
  transition: background 0.15s;
}

.ping-btn:hover { background: #111; }
.ping-btn:active { background: #222; }
.ping-btn:disabled { cursor: wait; }

/* progress bar */
.bar {
  width: clamp(260px, 26vw, 380px);
  height: 8px;
  border: 1px solid #fff;
  margin-top: 70px;
}

.bar-fill {
  width: 0%;
  height: 100%;
  background: #fff;
}

/* result */
.result {
  margin-top: 70px;
}

.ping-number {
  font-size: clamp(72px, 9vw, 130px);
  font-weight: bold;
  line-height: 1;
}

.ping-number small {
  font-size: clamp(24px, 2.6vw, 38px);
  font-weight: normal;
  color: #999;
  margin-left: 10px;
}

.verdict {
  color: #999;
  font-size: clamp(18px, 2vw, 28px);
  margin-top: 14px;
}