* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: #efefef;
  color: #1d2940;
  font-family: Arial, Helvetica, sans-serif;
}

.shell {
  max-width: 900px;
  margin: 28px auto;
  padding: 0 16px;
}

.card {
  background: #fff;
  border-radius: 18px;
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.08);
  padding: 26px 32px 32px;
}

h1 {
  color: #2855d4;
  font-size: 3rem;
  margin: 4px 0 18px;
  text-align: center;
}

h2, h3 {
  color: #11223c;
  text-align: left;
}

.center {
  text-align: center;
}

.muted {
  color: #56657e;
}

.note {
  margin-top: 24px;
  line-height: 1.5;
}

.grid.two {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
}

label {
  display: block;
  margin: 12px 0 8px;
  font-weight: 700;
}

input,
textarea {
  width: 100%;
  border: 1px solid #c9d1dc;
  border-radius: 10px;
  padding: 14px;
  font-size: 1.05rem;
}

textarea {
  resize: vertical;
  min-height: 180px;
}

button.primary,
button.secondary {
  width: 100%;
  margin-top: 20px;
  padding: 15px 18px;
  font-size: 1.15rem;
  font-weight: 700;
  border: 0;
  border-radius: 10px;
  cursor: pointer;
}

button.primary {
  color: #fff;
  background: #2f63e0;
}

button.secondary {
  color: #fff;
  background: #d09d00;
}

.alert {
  border-radius: 10px;
  padding: 18px;
  margin-top: 16px;
  line-height: 1.5;
}

.alert.success {
  background: #ebf7ef;
  border: 1px solid #b9e4c2;
  color: #10793f;
}

.alert.warning {
  background: #fff8db;
  border: 1px solid #e8cf4f;
  color: #664b00;
}

.alert.danger {
  background: #fdeaea;
  border: 1px solid #efb1b1;
  color: #a21d1d;
}

.hidden {
  display: none !important;
}

.linkbox {
  background: #fff8db;
  border: 1px solid #e8cf4f;
  border-radius: 10px;
  padding: 16px;
  margin-top: 18px;
}

.linkbox input {
  margin-top: 10px;
}

.message-box {
  border: 2px solid #6be28f;
  background: #ffffff;
  padding: 18px;
  border-radius: 10px;
  min-height: 56px;
  font-size: 1.15rem;
}

.success-text {
  color: #0e8e3a;
  text-align: center;
}

.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(20, 28, 43, 0.45);
  display: flex;
  align-items: center;
  justify-content: center;
}

.modal {
  background: white;
  width: min(520px, 92vw);
  border-radius: 12px;
  padding: 24px;
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.18);
}

@media (max-width: 720px) {
  .grid.two {
    grid-template-columns: 1fr;
  }

  h1 {
    font-size: 2.2rem;
  }

  .card {
    padding: 22px 18px 24px;
  }
}