:root {
  --bg: #e8ecef;
  --surface: #ffffff;
  --surface-alt: #f6f8fa;
  --ink: #1f2a37;
  --muted: #5b6673;
  --accent: #2B0B98;
  --accent-strong: #24009b;
  --line: #d3dbe3;
  --ok-bg: #e8f7ec;
  --ok-ink: #1f5a2b;
  --err-bg: #fdeceb;
  --err-ink: #8c2320;
  --radius: 14px;
  --shadow: 0 12px 28px rgba(24, 39, 58, 0.1);
  --content-max: 900px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  color: var(--ink);
  background:
    radial-gradient(circle at 8% -5%, #d2e8ff 0%, rgba(210, 232, 255, 0) 42%),
    radial-gradient(circle at 92% 8%, #dff5e6 0%, rgba(223, 245, 230, 0) 40%),
    var(--bg);
  line-height: 1.6;
}

header {
  padding: 2.3rem 1rem 1rem;
}

.header-inner {
  max-width: var(--content-max);
  margin: 0 auto;
  background: linear-gradient(145deg, var(--accent), var(--accent-strong));
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1.2rem;
  display: flex;
  gap: 1rem;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
}

.brand {
  margin: 0;
  color: #ffffff;
  line-height: 1.2;
  font-size: clamp(1.4rem, 2vw, 1.9rem);
  display: flex;
  align-items: center;
  gap: 0.45rem;
}

.brand .material-symbols-outlined {
  font-size: 2em;
  color: inherit;
  user-select: none;
}

.subtitle {
  margin: 0.35rem 0 0;
  color: rgba(255, 255, 255, 0.88);
  font-size: 0.98rem;
}

.lang-switch {
  display: inline-flex;
  border: 1px solid rgba(255, 255, 255, 0.45);
  border-radius: 999px;
  overflow: hidden;
  background: rgba(255, 255, 255, 0.16);
}

.lang-switch button {
  border: 0;
  background: transparent;
  color: rgba(255, 255, 255, 0.92);
  padding: 0.55rem 0.95rem;
  font-weight: 700;
  cursor: pointer;
  min-width: 74px;
}

.lang-switch button[aria-pressed="true"] {
  background: rgba(255, 255, 255, 0.26);
  color: #fff;
}

main {
  padding: 0 1rem 2.4rem;
}

.panel {
  max-width: var(--content-max);
  margin: 0 auto;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: clamp(1rem, 2.5vw, 2rem);
}

.page {
  display: none;
  animation: fadein 180ms ease;
}

.page.active {
  display: block;
}

h2 {
  margin-top: 1.6rem;
  margin-bottom: 0.45rem;
  font-size: 1.2rem;
  color: var(--accent-strong);
  border-top: 1px solid var(--line);
  padding-top: 1rem;
}

h2:first-of-type {
  margin-top: 0;
  border-top: 0;
  padding-top: 0;
}

p {
  margin: 0.55rem 0;
}

ul {
  margin: 0.3rem 0 0.9rem 1.2rem;
}

li {
  margin: 0.2rem 0;
}

.meta {
  margin: 0.55rem 0 1.1rem;
  color: var(--muted);
  font-size: 0.95rem;
}

.btn {
  border: 0;
  border-radius: 10px;
  padding: 0.68rem 1rem;
  font-weight: 700;
  cursor: pointer;
}

.btn-primary {
  color: #ffffff;
  background: var(--accent);
}

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

.btn-danger {
  color: #ffffff;
  background: #a81d1d;
}

.btn-danger:hover {
  background: #871515;
}

.btn:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}

.status {
  margin-top: 0.8rem;
  border-radius: 10px;
  padding: 0.7rem 0.8rem;
  display: none;
}

.status.show {
  display: block;
}

.status.ok {
  background: var(--ok-bg);
  color: var(--ok-ink);
}

.status.error {
  background: var(--err-bg);
  color: var(--err-ink);
}

.warning {
  margin-top: 1rem;
  border: 1px dashed var(--line);
  border-radius: 10px;
  background: var(--surface-alt);
  padding: 0.85rem;
  color: var(--muted);
}

.field {
  margin: 0.7rem 0;
}

.field label {
  display: block;
  margin-bottom: 0.25rem;
  font-weight: 600;
}

.field input {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 0.6rem 0.65rem;
  font-size: 0.95rem;
}

.actions {
  display: flex;
  gap: 0.7rem;
  flex-wrap: wrap;
  margin-top: 0.7rem;
}

@keyframes fadein {
  from {
    opacity: 0;
    transform: translateY(2px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (max-width: 640px) {
  .header-inner {
    padding: 1rem;
  }

  .lang-switch button {
    min-width: 64px;
    padding: 0.5rem 0.72rem;
  }
}