:root,
[data-theme="light"] {
  --bg: #f4f7fb;
  --panel: #ffffff;
  --panel-2: #eef3f9;
  --text: #0f172a;
  --muted: #475569;
  --border: #d8e1ec;
  --primary: #0f766e;
  --primary-strong: #115e59;
  --danger: #b91c1c;
  --shadow: 0 12px 30px rgba(15, 23, 42, 0.08);
}

[data-theme="dark"] {
  --bg: #020817;
  --panel: #0f172a;
  --panel-2: #111c33;
  --text: #e5eefb;
  --muted: #94a3b8;
  --border: #243247;
  --primary: #14b8a6;
  --primary-strong: #0f766e;
  --danger: #f87171;
  --shadow: 0 16px 40px rgba(0, 0, 0, 0.35);
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
}

.hidden { display: none !important; }

.skip-link {
  position: absolute;
  left: 12px;
  top: 12px;
  transform: translateY(-200%);
  background: var(--panel);
  color: var(--text);
  padding: 10px 14px;
  border-radius: 10px;
  z-index: 100;
}
.skip-link:focus { transform: translateY(0); }

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 20px;
  border-bottom: 1px solid var(--border);
  background: var(--panel);
  position: sticky;
  top: 0;
  z-index: 20;
}

.brand-wrap {
  display: flex;
  align-items: center;
  gap: 14px;
}

.brand-icon {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  background: var(--panel-2);
  padding: 6px;
}

.app-title {
  margin: 0;
  font-size: 28px;
  line-height: 1.1;
}

.app-subtitle {
  margin: 4px 0 0;
  color: var(--muted);
  font-size: 14px;
}

.icon-btn,
.primary-btn,
.secondary-btn,
.ghost-btn,
.numpad button {
  border: 1px solid var(--border);
  border-radius: 12px;
  min-height: 42px;
  padding: 10px 14px;
  cursor: pointer;
  font: inherit;
  transition: 0.2s ease;
}

.icon-btn {
  background: var(--panel-2);
  color: var(--text);
}

.primary-btn {
  background: var(--primary);
  color: white;
  border-color: var(--primary);
}

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

.secondary-btn,
.ghost-btn,
.numpad button {
  background: var(--panel);
  color: var(--text);
}

.shell {
  width: min(1200px, calc(100% - 24px));
  margin: 24px auto 40px;
}

.panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 20px;
  box-shadow: var(--shadow);
  padding: 20px;
}

.auth-panel {
  max-width: 520px;
  margin: 0 auto 20px;
}

.panel-head h2 {
  margin: 0 0 8px;
  font-size: 24px;
}

.panel-head p {
  margin: 0 0 18px;
  color: var(--muted);
}

.auth-form,
.field {
  display: grid;
  gap: 8px;
}

.field {
  margin-bottom: 16px;
}

.field span {
  font-size: 14px;
  color: var(--muted);
}

input[type="text"],
input[type="password"],
textarea {
  width: 100%;
  border: 1px solid var(--border);
  border-radius: 14px;
  background: var(--panel-2);
  color: var(--text);
  padding: 12px 14px;
  font: inherit;
}

textarea {
  resize: vertical;
  min-height: 280px;
}

.numpad {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
  margin-bottom: 16px;
}

.app-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 20px;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 14px;
}

.file-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.result-card {
  border: 1px solid var(--border);
  border-radius: 16px;
  background: var(--panel-2);
  padding: 16px;
  margin-top: 14px;
}

.result-card h3 {
  margin: 0 0 10px;
  font-size: 18px;
}

.result-body {
  color: var(--text);
  white-space: pre-wrap;
  line-height: 1.6;
}

.danger-card {
  border-color: rgba(185, 28, 28, 0.25);
}

.status-text {
  min-height: 24px;
  color: var(--muted);
  margin-top: 12px;
}

@media (max-width: 900px) {
  .app-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  .topbar {
    padding: 16px;
    align-items: flex-start;
  }

  .brand-wrap {
    align-items: flex-start;
  }

  .shell {
    width: min(100% - 16px, 1200px);
    margin-top: 16px;
  }

  .panel,
  .auth-panel {
    padding: 16px;
    border-radius: 16px;
  }

  .app-title {
    font-size: 24px;
  }

  textarea {
    min-height: 220px;
  }
}