:root {
  --bg: #f5f6f8;
  --fg: #1a1a2e;
  --accent: #3a6ff0;
  --border: #e0e2e8;
  --card-bg: #ffffff;
  --muted: #8a8f9c;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--fg);
}

.landing { min-height: 100vh; display: flex; flex-direction: column; }

.site-header {
  padding: 18px 20px 14px;
  border-bottom: 1px solid var(--border);
  background: var(--card-bg);
}

.logo { font-weight: 700; font-size: 17px; }
.tagline { margin-top: 4px; color: var(--muted); font-size: 12px; }

.site-main {
  flex: 1;
  padding: 20px 16px 32px;
}

.tool-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
  max-width: 640px;
  margin: 0 auto;
}

@media (min-width: 560px) {
  .tool-grid { grid-template-columns: repeat(3, 1fr); }
}

.tool-card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px 14px;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  text-decoration: none;
  color: inherit;
}

.tool-icon { font-size: 26px; margin-bottom: 8px; }
.tool-name { font-weight: 600; font-size: 14px; margin-bottom: 2px; }
.tool-desc { color: var(--muted); font-size: 11px; line-height: 1.4; }

.tool-card--link {
  transition: transform 0.12s ease, box-shadow 0.12s ease;
}
.tool-card--link:active { transform: scale(0.97); }

.tool-card--top {
  max-width: 640px;
  margin: 0 auto 16px;
  border-color: #c7d3f7;
  box-shadow: 0 2px 10px rgba(58, 111, 240, 0.08);
}

.tool-textarea {
  width: 100%;
  margin-top: 8px;
  padding: 8px 10px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 13px;
  font-family: inherit;
  resize: none;
}

.tool-input {
  flex: 1;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 14px;
}

.tool-btn-row { display: flex; gap: 6px; margin-top: 8px; width: 100%; }
.tool-btn-sm {
  flex: 1;
  padding: 8px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: #f3f4f7;
  font-size: 12px;
  cursor: pointer;
}
.tool-btn-sm:active { background: #e7e9ee; }

.tool-result {
  margin-top: 8px;
  font-size: 11px;
  color: var(--muted);
  word-break: break-all;
  min-height: 14px;
}

.input-row { display: flex; gap: 8px; width: 100%; margin-top: 10px; }

#code-input {
  flex: 1;
  padding: 12px 14px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 16px;
  letter-spacing: 2px;
  text-align: center;
}

#submit-btn {
  padding: 12px 20px;
  border: none;
  border-radius: 8px;
  background: var(--accent);
  color: #fff;
  font-size: 15px;
  cursor: pointer;
}

#submit-btn:disabled { background: #b7c3e0; cursor: not-allowed; }

.error { margin-top: 12px; color: #d33; font-size: 13px; text-align: center; }
.loading { margin-top: 12px; color: var(--muted); font-size: 13px; text-align: center; }

.site-footer { padding: 18px; text-align: center; color: #999; font-size: 12px; }

.frame-container {
  position: fixed;
  inset: 0;
  background: #000;
}

.content-frame {
  width: 100%;
  height: 100%;
  border: none;
}