:root {
  --bg: #f6f8fb;
  --bg-accent: radial-gradient(circle at 10% 10%, #e7efff, transparent 45%),
    radial-gradient(circle at 90% 20%, #dff7f0, transparent 40%);
  --card: rgba(255, 255, 255, 0.88);
  --text: #0f172a;
  --muted: #475569;
  --line: #dbe4ee;
  --line-soft: #e8eef5;
  --primary: #1d4ed8;
  --primary-strong: #1e40af;
  --radius: 14px;
  --shadow: 0 14px 38px -28px rgba(15, 23, 42, 0.55);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Segoe UI", "SF Pro Text", "Helvetica Neue", sans-serif;
  color: var(--text);
  background-color: var(--bg);
  background-image: var(--bg-accent);
}

.container {
  max-width: 1120px;
  margin: 0 auto;
  padding: 42px 20px 28px;
}

h1 {
  margin: 0;
  font-size: clamp(1.9rem, 1.25rem + 2vw, 2.4rem);
  letter-spacing: -0.02em;
}

h2 {
  margin: 0 0 12px;
  font-size: 1.15rem;
  letter-spacing: -0.01em;
}

.sub {
  margin: 8px 0 22px;
  color: var(--muted);
  max-width: 58ch;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(290px, 1fr));
  gap: 16px;
  align-items: start;
}

.card {
  background: var(--card);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  padding: 16px;
  box-shadow: var(--shadow);
  backdrop-filter: blur(6px);
}

.mode-switch {
  display: flex;
  gap: 10px;
  margin-bottom: 14px;
}

.mode-switch button {
  flex: 1;
}

form {
  display: grid;
  gap: 10px;
}

label {
  display: grid;
  gap: 6px;
  font-size: 0.9rem;
  color: var(--muted);
}

input,
select,
button {
  font: inherit;
}

input,
select {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 10px 12px;
  background: #fff;
  color: var(--text);
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

input::placeholder {
  color: #94a3b8;
}

input:focus,
select:focus {
  outline: none;
  border-color: #93c5fd;
  box-shadow: 0 0 0 4px #dbeafe;
}

button {
  border: 0;
  border-radius: 10px;
  padding: 10px 13px;
  font-weight: 600;
  color: #fff;
  background: linear-gradient(135deg, var(--primary), var(--primary-strong));
  cursor: pointer;
  transition: transform 0.16s ease, box-shadow 0.16s ease, filter 0.16s ease;
  box-shadow: 0 10px 24px -18px rgba(30, 64, 175, 0.9);
}

button:hover {
  filter: brightness(1.03);
  transform: translateY(-1px);
}

button:active {
  transform: translateY(0);
}

button:disabled {
  cursor: not-allowed;
  filter: grayscale(0.35);
  opacity: 0.72;
}

.danger-btn {
  margin-left: 8px;
  background: linear-gradient(135deg, #dc2626, #b91c1c);
}

.inline-form {
  grid-template-columns: 1fr auto;
}

ul {
  list-style: none;
  padding: 0;
  margin: 12px 0 0;
  display: grid;
  gap: 8px;
}

li {
  background: #fff;
  border: 1px solid var(--line-soft);
  border-radius: 10px;
  padding: 10px;
  line-height: 1.35;
}

li button {
  margin-left: 8px;
  padding: 6px 10px;
  font-size: 0.85rem;
}

fieldset {
  margin: 0;
  padding: 8px 10px 10px;
  border: 1px solid var(--line);
  border-radius: 10px;
}

legend {
  font-size: 0.85rem;
  color: var(--muted);
  padding: 0 6px;
}

.check {
  display: block;
  margin: 6px 0;
}

.check input {
  width: auto;
  margin-right: 6px;
}

#meLabel {
  margin: 0 0 10px;
  color: var(--muted);
  font-size: 0.95rem;
}

.muted {
  color: var(--muted);
  margin: 6px 0 0;
}

.hidden {
  display: none;
}

@media (max-width: 720px) {
  .container {
    padding: 24px 14px;
  }

  .grid {
    grid-template-columns: 1fr;
  }

  .inline-form {
    grid-template-columns: 1fr;
  }
}