* {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 20px;
  font-family: Arial, sans-serif;
  background: linear-gradient(135deg, #fff1f2, #f8fafc);
  color: #1f2937;
}

.tool-card {
  max-width: 680px;
  margin: 0 auto;
  background: #ffffff;
  border-radius: 24px;
  padding: 28px;
  box-shadow: 0 15px 40px rgba(159, 18, 57, 0.12);
  border: 1px solid #ffe4e6;
}

.header {
  text-align: center;
  margin-bottom: 24px;
}

.badge {
  display: inline-block;
  background: #ffe4e6;
  color: #be123c;
  padding: 7px 14px;
  border-radius: 999px;
  font-size: 14px;
  font-weight: bold;
  margin-bottom: 10px;
}

h1 {
  margin: 0;
  font-size: 30px;
  color: #0f172a;
}

.header p {
  margin: 10px 0 0;
  color: #64748b;
  font-size: 15px;
}

.field {
  margin-bottom: 18px;
}

label {
  display: block;
  font-weight: bold;
  margin-bottom: 7px;
  color: #334155;
}

.input-wrap {
  display: flex;
  align-items: center;
  gap: 10px;
}

.input-wrap span {
  font-weight: bold;
  color: #475569;
}

input {
  width: 100%;
  border: 1px solid #fecdd3;
  border-radius: 14px;
  padding: 14px;
  font-size: 17px;
  outline: none;
  background: #fff1f2;
}

input:focus {
  border-color: #e11d48;
  background: #ffffff;
  box-shadow: 0 0 0 4px rgba(225, 29, 72, 0.12);
}

button {
  width: 100%;
  margin-top: 12px;
  border: none;
  border-radius: 16px;
  padding: 16px;
  font-size: 18px;
  font-weight: bold;
  color: white;
  background: linear-gradient(135deg, #e11d48, #fb7185);
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

button:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 25px rgba(225, 29, 72, 0.25);
}

.results {
  margin-top: 24px;
  display: grid;
  gap: 12px;
}

.zone {
  border-radius: 18px;
  padding: 16px 18px;
  display: flex;
  justify-content: space-between;
  gap: 12px;
  align-items: center;
  border: 1px solid #e5e7eb;
}

.zone span {
  font-size: 15px;
  color: #334155;
  font-weight: bold;
}

.zone strong {
  font-size: 20px;
  color: #0f172a;
}

.z1 { background: #ecfdf5; }
.z2 { background: #f0fdf4; }
.z3 { background: #fffbeb; }
.z4 { background: #fff7ed; }
.z5 { background: #fff1f2; }

.error {
  color: #dc2626;
  text-align: center;
  font-weight: bold;
  margin-top: 15px;
}

.note {
  margin-top: 20px;
  font-size: 13px;
  color: #64748b;
  text-align: center;
  line-height: 1.5;
}

.hidden {
  display: none;
}

@media (max-width: 520px) {
  body {
    padding: 12px;
  }

  .tool-card {
    padding: 22px;
    border-radius: 20px;
  }

  h1 {
    font-size: 25px;
  }

  .zone {
    flex-direction: column;
    text-align: center;
  }
}