* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: Arial, Helvetica, sans-serif;
  background: #f4f6f8;
  color: #17202a;
}

.phone {
  width: min(520px, 100%);
  margin: 0 auto;
  padding: 20px;
}

.status,
.panel {
  background: #fff;
  border: 1px solid #d7dde4;
  border-radius: 8px;
  padding: 14px;
  margin-bottom: 12px;
}

.status {
  display: grid;
  gap: 10px;
}

span,
label {
  display: block;
  margin-bottom: 5px;
  color: #5d6a78;
  font-size: 13px;
}

strong {
  display: block;
  font-size: 18px;
}

input {
  width: 100%;
  height: 44px;
  border: 1px solid #b9c4d0;
  border-radius: 6px;
  padding: 0 12px;
  font-size: 18px;
}

input:focus {
  outline: 2px solid #176bd8;
  outline-offset: 1px;
}

.row,
.actions {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 10px;
}

button {
  min-width: 86px;
  min-height: 44px;
  border: 1px solid #aab6c4;
  border-radius: 6px;
  background: #fff;
  color: #17202a;
  font-size: 16px;
  font-weight: 700;
  cursor: pointer;
}

button:disabled {
  color: #98a3af;
  cursor: not-allowed;
}

#registerBtn,
#callBtn {
  background: #176bd8;
  border-color: #176bd8;
  color: #fff;
}

#hangupBtn {
  background: #b92727;
  border-color: #b92727;
  color: #fff;
}

.dialpad {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
  margin: 12px 0;
}

.dialpad button {
  height: 54px;
  min-width: 0;
  font-size: 22px;
}

.enable-audio {
  width: 100%;
  margin-top: 0.75rem;
  padding: 0.8rem 1rem;
  font-weight: 700;
  color: #fff;
  background: #1769e0;
  border: 0;
  border-radius: 0.5rem;
}

audio {
  display: block;
  width: 100%;
  margin-top: 12px;
}

@media (max-width: 440px) {
  .phone {
    padding: 12px;
  }

  .row,
  .actions {
    grid-template-columns: 1fr;
  }
}