:root {
  --color-bg: #f7f8fb;
  --color-surface: #ffffff;
  --color-border: #e4e7ec;
  --color-text: #1a1d29;
  --color-text-muted: #6b7280;
  --color-primary: #4f46e5;
  --color-primary-dark: #4338ca;
  --color-danger: #dc2626;
  --radius: 12px;
  --container-width: 1080px;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.55;
}

.container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 16px;
}

a { color: var(--color-primary); text-decoration: none; }

/* ---------- Header ---------- */
.site-header {
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 20;
}
.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 60px;
}
.brand { font-weight: 700; font-size: 1.25rem; color: var(--color-text); }

.nav-toggle {
  display: flex;
  flex-direction: column;
  gap: 4px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}
.nav-toggle span { width: 22px; height: 2px; background: var(--color-text); border-radius: 2px; }

.site-nav {
  display: flex;
  align-items: center;
  gap: 20px;
}
.auth-area { display: flex; align-items: center; gap: 12px; }
.user-area { display: flex; align-items: center; gap: 10px; }
.user-email { font-size: 0.9rem; color: var(--color-text-muted); }
.user-credits {
  font-size: 0.8rem;
  background: #eef2ff;
  color: var(--color-primary);
  padding: 2px 8px;
  border-radius: 999px;
}

@media (max-width: 720px) {
  .nav-toggle { display: flex; }
  .site-nav {
    position: absolute;
    top: 60px;
    left: 0;
    right: 0;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    flex-direction: column;
    align-items: stretch;
    padding: 12px 16px 20px;
    gap: 14px;
    display: none;
  }
  .site-nav.is-open { display: flex; }
  .auth-area { flex-direction: column; align-items: stretch; }
  .user-area { flex-direction: column; align-items: flex-start; }
}
@media (min-width: 721px) {
  .nav-toggle { display: none; }
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-block;
  border: 1px solid transparent;
  border-radius: var(--radius);
  padding: 8px 16px;
  font-size: 0.9rem;
  cursor: pointer;
  font-weight: 600;
}
.btn--primary { background: var(--color-primary); color: #fff; width: 100%; }
.btn--primary:hover { background: var(--color-primary-dark); }
.btn--ghost { background: transparent; border-color: var(--color-border); color: var(--color-text); }
.btn--ghost:hover { background: var(--color-bg); }

/* ---------- Hero / Home ---------- */
.hero { text-align: center; padding: 48px 0 24px; }
.hero h1 { font-size: 2rem; margin-bottom: 8px; }
.hero p { color: var(--color-text-muted); }

.tool-category { margin: 32px 0; }
.tool-category h2 { font-size: 1.25rem; margin-bottom: 16px; }

.tool-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 16px;
}
.tool-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  transition: box-shadow 0.15s, transform 0.15s;
}
.tool-card:hover { box-shadow: 0 6px 20px rgba(0,0,0,0.06); transform: translateY(-2px); }
.tool-card__icon { font-size: 1.75rem; }
.tool-card__name { font-weight: 600; color: var(--color-text); }
.tool-card__desc { font-size: 0.85rem; color: var(--color-text-muted); }

/* ---------- Tool page ---------- */
.breadcrumb { margin: 20px 0 8px; font-size: 0.85rem; color: var(--color-text-muted); }
.tool-page { padding-bottom: 48px; }
.tool-page__header { display: flex; align-items: center; gap: 16px; margin: 12px 0 20px; }
.tool-icon { font-size: 2.5rem; }
.tool-page__desc { color: var(--color-text-muted); margin: 4px 0 0; }

.tool-page__body {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 24px;
}
@media (max-width: 480px) {
  .tool-page__body { padding: 16px; }
}

.usage-banner {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  margin-bottom: 12px;
  min-height: 1.2em;
}
.usage-banner--blocked { color: var(--color-danger); font-weight: 600; }

/* generic form bits reused across tools */
.field { display: flex; flex-direction: column; gap: 6px; margin-bottom: 14px; }
.field label { font-size: 0.85rem; font-weight: 600; }
.field input, .field select, .field textarea {
  border: 1px solid var(--color-border);
  border-radius: 8px;
  padding: 10px 12px;
  font-size: 1rem;
  width: 100%;
  font-family: inherit;
}
.field textarea { font-family: "SFMono-Regular", Consolas, Menlo, monospace; }
.form-row { display: grid; grid-template-columns: repeat(auto-fit, minmax(160px, 1fr)); gap: 14px; }
.checkbox-field { display: flex; align-items: center; gap: 8px; font-size: 0.9rem; font-weight: normal; }
.checkbox-field input { width: auto; }

.result-box {
  margin-top: 16px;
  padding: 16px;
  border-radius: 8px;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
}
.result-box__value { font-size: 1.6rem; font-weight: 700; color: var(--color-primary); }
.result-box.is-error { color: var(--color-danger); border-color: var(--color-danger); background: #fef2f2; }

.dropzone {
  border: 2px dashed var(--color-border);
  border-radius: var(--radius);
  padding: 32px;
  text-align: center;
  color: var(--color-text-muted);
  cursor: pointer;
}
.dropzone.is-dragover { border-color: var(--color-primary); color: var(--color-primary); background: #eef2ff; }

/* ---------- Modal ---------- */
.modal { position: fixed; inset: 0; z-index: 50; display: flex; align-items: center; justify-content: center; }
.modal[hidden] { display: none; }
.modal__backdrop { position: absolute; inset: 0; background: rgba(17, 19, 28, 0.5); }
.modal__panel {
  position: relative;
  background: var(--color-surface);
  border-radius: var(--radius);
  padding: 28px;
  width: 90%;
  max-width: 380px;
}
.modal__close { position: absolute; top: 12px; right: 14px; border: none; background: none; font-size: 1.4rem; cursor: pointer; color: var(--color-text-muted); }
.modal__hint { color: var(--color-text-muted); font-size: 0.85rem; margin-top: -8px; margin-bottom: 16px; }
.stack { display: flex; flex-direction: column; gap: 10px; }
.stack input {
  border: 1px solid var(--color-border);
  border-radius: 8px;
  padding: 10px 12px;
  font-size: 1rem;
}
.auth-message { min-height: 1.2em; font-size: 0.85rem; color: var(--color-danger); margin-top: 10px; margin-bottom: 0; }

.tool-info { margin-top: 32px; color: var(--color-text-muted); font-size: 0.9rem; }
.tool-info h2 { font-size: 1.05rem; color: var(--color-text); margin-bottom: 8px; }

.jf-string { color: #15803d; }
.jf-number { color: #b45309; }
.jf-boolean { color: #7c3aed; }
.jf-null { color: #6b7280; }
.jf-key { color: #1d4ed8; }

/* ---------- Footer / Ads ---------- */
.site-footer { margin-top: 48px; padding: 24px 0; color: var(--color-text-muted); font-size: 0.85rem; text-align: center; }
.ad-slot { text-align: center; margin: 16px 0; }