* {
  box-sizing: border-box;
}

:root {
  --bg: #f4f6fb;
  --card: #ffffff;
  --text: #1f2430;
  --muted: #6b7280;
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --border: #d6dae3;
  --danger: #dc2626;
  --success: #16a34a;
}

html,
body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
}

.page {
  max-width: 760px;
  margin: 0 auto;
  padding: 32px 20px 48px;
}

.header {
  text-align: center;
  margin-bottom: 28px;
}

.client-name {
  margin: 0 0 6px;
  font-size: 26px;
  line-height: 1.2;
  color: var(--text);
}

.subtitle {
  margin: 0;
  color: var(--muted);
}

#form-box,
.success-box,
.error-box {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 28px;
  box-shadow: 0 2px 10px rgba(16, 24, 40, 0.05);
}

.hidden {
  display: none;
}

.error-box {
  border-color: var(--danger);
}

.error-box h2 {
  color: var(--danger);
  margin-top: 0;
}

.success-box {
  text-align: center;
}

.success-box h2 {
  color: var(--success);
  margin-top: 0;
}

.muted {
  color: var(--muted);
}

.field {
  display: flex;
  flex-direction: column;
  margin-bottom: 18px;
  flex: 1;
}

.row {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.field label,
.fieldset legend {
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 6px;
}

.fieldset {
  border: none;
  margin: 0 0 18px;
  padding: 0;
}

.fieldset legend {
  margin-bottom: 12px;
}

input,
select,
textarea {
  width: 100%;
  padding: 10px 12px;
  font-size: 15px;
  font-family: inherit;
  color: var(--text);
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 8px;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

input:focus,
select:focus,
textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
}

textarea {
  resize: vertical;
}

.submit-btn {
  display: inline-block;
  width: 100%;
  padding: 12px 20px;
  font-size: 16px;
  font-weight: 600;
  color: #fff;
  background: var(--primary);
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: background 0.15s ease;
}

.submit-btn:hover {
  background: var(--primary-hover);
}

.submit-btn:disabled {
  background: var(--muted);
  cursor: not-allowed;
}

.field-error {
  color: var(--danger);
  font-size: 13px;
  margin-top: 4px;
  min-height: 16px;
}

@media (max-width: 560px) {
  .row {
    flex-direction: column;
    gap: 0;
  }
}