:root {
  --lapis: #1b3a4b;
  --lapis-dark: #12262f;
  --turquoise: #2a9d8f;
  --turquoise-light: #7fc9bd;
  --gold: #c9a227;
  --gold-light: #e6c65c;
  --cream: #fbf6ec;
  --paper: #fffdf8;
  --ink: #1b3a4b;
  --ink-soft: #4a6470;
  --error: #b3452c;
  --radius: 18px;
  --shadow: 0 20px 50px -20px rgba(18, 38, 47, 0.45);
}

h1 {
  margin: 0 0 8px;
  font-size: 30px;
  font-weight: 800;
  color: var(--lapis);
}

.subtitle {
  margin: 0 0 28px;
  color: var(--ink-soft);
  font-size: 14.5px;
  line-height: 1.9;
}

.date-form {
  display: grid;
  grid-template-columns: 1fr 1fr 1.3fr;
  gap: 10px;
  margin-bottom: 20px;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.field label {
  font-size: 12px;
  font-weight: 600;
  color: var(--ink-soft);
}

select {
  font-family: inherit;
  font-size: 15px;
  padding: 12px 10px;
  border-radius: 10px;
  border: 1.5px solid #e2d9c3;
  background: var(--cream);
  color: var(--ink);
  appearance: none;
  text-align: center;
  cursor: pointer;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

select:focus-visible {
  outline: none;
  border-color: var(--turquoise);
  box-shadow: 0 0 0 3px rgba(42, 157, 143, 0.25);
}

.calc-btn {
  width: 100%;
  font-family: inherit;
  font-size: 16px;
  font-weight: 700;
  color: var(--paper);
  background: linear-gradient(135deg, var(--turquoise) 0%, var(--lapis) 100%);
  border: none;
  border-radius: 12px;
  padding: 14px;
  cursor: pointer;
  transition: transform 0.12s ease, box-shadow 0.12s ease;
  box-shadow: 0 10px 24px -10px rgba(27, 58, 75, 0.55);
}

.calc-btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 14px 28px -10px rgba(27, 58, 75, 0.6);
}

.calc-btn:active {
  transform: translateY(0);
}

.error-box {
  margin-top: 16px;
  background: rgba(179, 69, 44, 0.08);
  border: 1px solid rgba(179, 69, 44, 0.3);
  color: var(--error);
  padding: 12px 14px;
  border-radius: 10px;
  font-size: 13.5px;
  text-align: center;
}

.result {
  margin-top: 28px;
  padding-top: 26px;
  border-top: 1px dashed #e2d9c3;
  animation: fadeUp 0.35s ease;
}

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

.result-main {
  display: flex;
  gap: 12px;
  justify-content: center;
  margin-bottom: 18px;
}

.chip {
  flex: 1;
  background: var(--cream);
  border: 1.5px solid var(--gold-light);
  border-radius: 14px;
  padding: 16px 8px;
  text-align: center;
}

.chip-num {
  display: block;
  font-size: 28px;
  font-weight: 800;
  color: var(--lapis);
  line-height: 1.2;
}

.chip-label {
  display: block;
  font-size: 12.5px;
  color: var(--ink-soft);
  margin-top: 4px;
  font-weight: 600;
}

.result-extra {
  text-align: center;
  font-size: 13px;
  color: var(--ink-soft);
  line-height: 1.9;
}

.result-extra span {
  color: var(--turquoise);
  font-weight: 700;
}

.foot {
  position: relative;
  z-index: 1;
  margin-top: 22px;
  color: rgba(15, 15, 15, 0.65);
  font-size: 13px;
}

.foot span {
  color: var(--gold-light);
  font-weight: 600;
}

@media (max-width: 400px) {

  .date-form {
    grid-template-columns: 1fr 1fr 1.2fr;
    gap: 8px;
  }
  h1 {
    font-size: 25px;
  }
}