:root {
  color-scheme: light;
  --background: #f5f7fb;
  --surface: #ffffff;
  --ink: #1f2933;
  --muted: #6f7785;
  --line: #dbe3ef;
  --accent: #2f6fdf;
  --accent-strong: #1f55bd;
  --success: #18834f;
  --success-soft: #e8f6ee;
  --danger: #bb3e3e;
  --shadow: 0 18px 45px rgba(34, 47, 73, 0.12);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background:
    radial-gradient(circle at top left, rgba(47, 111, 223, 0.14), transparent 34rem),
    linear-gradient(135deg, #f5f7fb 0%, #edf3f8 100%);
  color: var(--ink);
}

button {
  font: inherit;
}

.app-shell {
  width: min(100%, 760px);
  margin: 0 auto;
  padding: 32px 18px;
}

.hero {
  padding: 28px 4px 22px;
}

.label {
  margin: 0 0 8px;
  color: var(--accent);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0;
  text-transform: uppercase;
}

h1 {
  margin: 0;
  font-size: 56px;
  line-height: 0.96;
  letter-spacing: 0;
}

#invite-meta {
  max-width: 560px;
  margin: 14px 0 0;
  color: var(--muted);
  font-size: 17px;
  line-height: 1.5;
}

.panel {
  background: rgba(255, 255, 255, 0.9);
  border: 1px solid rgba(226, 222, 213, 0.88);
  border-radius: 8px;
  box-shadow: var(--shadow);
  padding: 22px;
}

.stack {
  display: grid;
  gap: 18px;
}

.loading-state,
.empty-state {
  color: var(--muted);
  line-height: 1.5;
}

.person-grid,
.slot-list {
  display: grid;
  gap: 10px;
}

.person-button,
.slot-button,
.primary-button,
.secondary-button {
  min-height: 48px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  color: var(--ink);
  cursor: pointer;
  transition: border-color 160ms ease, transform 160ms ease, background 160ms ease;
}

.person-button,
.slot-button {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 14px;
  padding: 14px 16px;
  text-align: left;
}

.person-button:hover,
.slot-button:hover,
.primary-button:hover,
.secondary-button:hover {
  transform: translateY(-1px);
}

.person-button[aria-pressed="true"],
.slot-button[aria-pressed="true"] {
  border-color: var(--accent);
  background: #edf4ff;
}

.slot-button[aria-pressed="true"] .slot-status {
  color: var(--success);
}

.slot-date {
  font-weight: 700;
}

.slot-status,
.slot-count,
.slot-proposer,
.helper-text {
  color: var(--muted);
  font-size: 14px;
}

.slot-proposer {
  color: var(--accent-strong);
  font-weight: 650;
}

.button-row {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.calendar-actions {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.primary-button,
.secondary-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 0 18px;
  font-weight: 700;
  text-decoration: none;
}

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

.primary-button:disabled {
  opacity: 0.55;
  cursor: not-allowed;
  transform: none;
}

.secondary-button {
  background: transparent;
}

.proposal-box {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 14px 16px;
  background: rgba(247, 250, 255, 0.72);
}

.proposal-box summary {
  cursor: pointer;
  font-weight: 700;
}

.proposal-fields {
  display: grid;
  gap: 12px;
  padding-top: 14px;
}

.proposal-fields label {
  display: grid;
  gap: 6px;
  color: var(--muted);
  font-size: 14px;
  font-weight: 650;
}

.proposal-fields input,
.proposal-fields select {
  min-height: 44px;
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  color: var(--ink);
  font: inherit;
  padding: 0 12px;
}

.success-box {
  border: 1px solid #bde5cf;
  background: var(--success-soft);
  border-radius: 8px;
  padding: 16px;
}

.error-box {
  border: 1px solid #efc3c3;
  background: #fff0f0;
  color: var(--danger);
  border-radius: 8px;
  padding: 16px;
}

.final-time {
  display: grid;
  gap: 8px;
}

.final-time strong {
  font-size: 22px;
}

@media (max-width: 560px) {
  .app-shell {
    padding: 22px 14px;
  }

  .panel {
    padding: 16px;
  }

  h1 {
    font-size: 42px;
    line-height: 1;
  }

  .button-row {
    display: grid;
  }
}