:root {
  color-scheme: light;
  --bg: #eef2f7;
  --card-bg: #ffffff;
  --text: #0a0a0a;
  --muted: #5c6672;
  --accent: #1e3a5f;
  --accent-text: #ffffff;
  --accent-soft-bg: #e4ebf3;
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.04), 0 10px 30px rgba(0, 0, 0, 0.07);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px 16px;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

.card {
  width: 100%;
  max-width: 560px;
  background: var(--card-bg);
  border-radius: 20px;
  box-shadow: var(--shadow);
  padding: 40px;
}

h1 {
  font-size: 21px;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin: 0 0 6px;
  color: var(--text);
}

.subtitle {
  color: var(--muted);
  font-size: 14px;
  line-height: 1.5;
  margin: 0 0 28px;
}

label {
  display: block;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 8px;
}

textarea,
input[type="text"] {
  width: 100%;
  font-family: inherit;
  font-size: 14px;
  padding: 12px 14px;
  border: none;
  border-radius: 10px;
  background: var(--accent-soft-bg);
  color: var(--text);
  resize: vertical;
  transition: box-shadow 0.15s ease;
}

textarea::placeholder,
input::placeholder {
  color: var(--muted);
}

textarea:focus,
input[type="text"]:focus {
  outline: none;
  box-shadow: 0 0 0 2px var(--accent);
}

textarea {
  min-height: 150px;
  margin-bottom: 20px;
}

input[type="text"] {
  margin-bottom: 20px;
}

button {
  font-family: inherit;
  font-size: 14px;
  font-weight: 600;
  padding: 12px 20px;
  border-radius: 10px;
  border: none;
  cursor: pointer;
  transition: opacity 0.15s ease;
}

.btn-primary {
  background: var(--accent);
  color: var(--accent-text);
  width: 100%;
}

.btn-primary:hover:not(:disabled) {
  opacity: 0.9;
}

.btn-primary:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.btn-secondary {
  background: var(--accent-soft-bg);
  color: var(--accent);
}

.btn-secondary:hover {
  opacity: 0.85;
}

[hidden] {
  display: none !important;
}

.result-box {
  margin-top: 28px;
  padding-top: 28px;
}

.link-row {
  display: flex;
  gap: 8px;
  margin-bottom: 10px;
}

.link-row input {
  flex: 1;
  margin-bottom: 0;
}

.hint {
  color: var(--muted);
  font-size: 12px;
}

.warning {
  background: var(--accent-soft-bg);
  color: var(--accent);
  border-radius: 12px;
  padding: 14px 16px;
  font-size: 13px;
  line-height: 1.5;
  margin-bottom: 24px;
}

.secret-box {
  white-space: pre-wrap;
  word-break: break-word;
  background: var(--accent-soft-bg);
  border-radius: 12px;
  padding: 18px;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 14px;
  color: var(--text);
  margin-bottom: 20px;
  max-height: 50vh;
  overflow: auto;
}

.description {
  font-size: 14px;
  color: var(--muted);
  margin-bottom: 24px;
}

.error-text {
  background: var(--accent-soft-bg);
  color: var(--text);
  font-weight: 600;
  font-size: 14px;
  border-radius: 12px;
  padding: 14px 16px;
}

.copied-tag {
  font-size: 12px;
  color: var(--accent);
  margin-left: 8px;
}