*,
*::before,
*::after {
  box-sizing: border-box;
}

:root {
  --bg: #f3f5f7;
  --surface: #ffffff;
  --text: #1a1f24;
  --muted: #5c6770;
  --border: #d5dde3;
  --accent: #0f6e56;
  --accent-hover: #0c5a46;
  --danger: #b42318;
  --danger-bg: #fef3f2;
  --success: #027a48;
  --success-bg: #ecfdf3;
  --warning: #b54708;
  --warning-bg: #fffaeb;
  --radius: 10px;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Segoe UI", system-ui, -apple-system, sans-serif;
  color: var(--text);
  background:
    radial-gradient(ellipse at top, #e8eef2 0%, transparent 55%),
    var(--bg);
  line-height: 1.5;
}

.page {
  width: min(100%, 26rem);
  margin: 0 auto;
  padding: 1.5rem 1rem 2.5rem;
}

.header {
  margin-bottom: 1.25rem;
}

.header h1 {
  margin: 0 0 0.35rem;
  font-size: 1.5rem;
  font-weight: 650;
  letter-spacing: -0.02em;
}

.subtitle {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.message {
  margin-bottom: 1rem;
  padding: 0.85rem 1rem;
  border-radius: var(--radius);
  font-size: 0.95rem;
}

.message.success {
  color: var(--success);
  background: var(--success-bg);
}

.message.error {
  color: var(--danger);
  background: var(--danger-bg);
}

.message.warning {
  color: var(--warning);
  background: var(--warning-bg);
}

.form {
  display: grid;
  gap: 1rem;
  padding: 1.15rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: calc(var(--radius) + 2px);
}

.field {
  display: grid;
  gap: 0.35rem;
}

label {
  font-size: 0.875rem;
  font-weight: 600;
}

input {
  width: 100%;
  padding: 0.75rem 0.85rem;
  font: inherit;
  color: var(--text);
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  outline: none;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(15, 110, 86, 0.15);
}

input:disabled {
  opacity: 0.65;
  background: #f7f9fa;
}

input.invalid {
  border-color: var(--danger);
}

.field-error {
  margin: 0;
  color: var(--danger);
  font-size: 0.8rem;
}

.submit-btn {
  margin-top: 0.25rem;
  width: 100%;
  padding: 0.85rem 1rem;
  font: inherit;
  font-weight: 650;
  color: #fff;
  background: var(--accent);
  border: none;
  border-radius: var(--radius);
  cursor: pointer;
  transition: background 0.15s ease;
}

.submit-btn:hover:not(:disabled) {
  background: var(--accent-hover);
}

.submit-btn:disabled {
  opacity: 0.65;
  cursor: not-allowed;
}

@media (min-width: 480px) {
  .page {
    padding-top: 2.5rem;
  }
}