:root {
  color-scheme: light dark;
  --bg: #f4f5f7;
  --surface: #ffffff;
  --surface-hover: #f5f7fa;
  --ink: #1c2230;
  --muted: #676d78;
  --line: #dde0e6;
  --accent: #2563eb;
  --accent-hover: #1d4fd8;
  --accent-ink: #ffffff;
  --accent-soft: #e8effd;
  --warn: #a64b06;
  --danger: #c0241b;
  --card-border: transparent;
  --card-shadow: 0 1px 2px rgba(16, 24, 40, .05), 0 6px 20px rgba(16, 24, 40, .05);
  --sans: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, "SF Mono", SFMono-Regular, Menlo, Consolas, monospace;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #11141a;
    --surface: #1a1e26;
    --surface-hover: #232834;
    --ink: #eceef2;
    --muted: #a5abb7;
    --line: #333945;
    --accent: #7aa2ff;
    --accent-hover: #93b4ff;
    --accent-ink: #0b1424;
    --accent-soft: #1d2b49;
    --warn: #eda25b;
    --danger: #f28b82;
    --card-border: #2a2f3a;
    --card-shadow: none;
  }
}

* { box-sizing: border-box; }

[hidden] { display: none !important; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.5 var(--sans);
}

h1, h2, h3, p, ul { margin: 0; }

ul { padding: 0; list-style: none; }

h2 {
  font-size: 24px;
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -.01em;
}

.site-header, .layout, .site-footer {
  width: 100%;
  max-width: 1180px;
  margin-inline: auto;
  padding-inline: 16px;
}

.site-header {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 4px 16px;
  padding-block: 20px 16px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 18px;
  font-weight: 700;
}

.brand-mark { color: var(--accent); }

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

.layout { display: grid; gap: 20px; }

.columns { display: grid; gap: 20px; }

.card {
  min-width: 0;
  border: 1px solid var(--card-border);
  border-radius: 16px;
  background: var(--surface);
  box-shadow: var(--card-shadow);
  overflow: hidden;
}

.card-body { display: grid; gap: 16px; padding: 24px; align-content: start; }

.field, .field-label {
  color: var(--muted);
  font-size: 14px;
  font-weight: 600;
}

.field { display: grid; gap: 6px; min-width: 0; }

input[type="text"],
select {
  width: 100%;
  min-height: 46px;
  padding: 8px 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  color: var(--ink);
  font: 15px var(--sans);
}

input[type="text"]:focus-visible,
select:focus-visible {
  border-color: var(--accent);
  outline: 2px solid var(--accent-soft);
  outline-offset: 0;
}

.create-form {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

.at { display: none; }

.form-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px 16px;
}

.hint { flex: 1 1 280px; color: var(--muted); font-size: 13px; }

.button {
  min-height: 46px;
  padding: 8px 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: transparent;
  color: var(--ink);
  font: 600 15px var(--sans);
  cursor: pointer;
}

.button:hover:not(:disabled) { background: var(--surface-hover); }

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

.button.primary:hover:not(:disabled) {
  border-color: var(--accent-hover);
  background: var(--accent-hover);
}

.button:disabled { opacity: .5; cursor: default; }

.button:focus-visible,
.message-item:focus-visible,
a:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.icon-button {
  display: inline-grid;
  flex: none;
  place-items: center;
  width: 56px;
  padding: 0;
}

.error { color: var(--danger); font-size: 14px; }

.address-card { position: relative; }

.meter {
  position: absolute;
  inset: 0 0 auto;
  height: 4px;
  background: var(--line);
}

.meter-fill {
  width: 0;
  height: 100%;
  background: var(--accent);
  transition: width 1s linear, background-color .3s;
}

.address-card[data-urgency="warn"] .meter-fill { background: var(--warn); }
.address-card[data-urgency="danger"] .meter-fill { background: var(--danger); }
.address-card[data-urgency="warn"] #timer { color: var(--warn); }
.address-card[data-urgency="danger"] #timer { color: var(--danger); }

.address-card .card-body { gap: 12px; }

.address {
  display: block;
  font: 600 clamp(18px, 2.3vw, 24px)/1.3 var(--mono);
  overflow-wrap: anywhere;
}

.address-card[data-state="expired"] .address { color: var(--muted); }

.timer { color: var(--muted); font-size: 15px; }

.timer strong {
  color: var(--ink);
  font: 600 16px var(--mono);
  font-variant-numeric: tabular-nums;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 4px;
}

.actions .button { flex: 1 1 130px; }

.search-form { display: grid; gap: 6px; }

.search-row { display: flex; gap: 8px; }

.search-row input { flex: 1 1 auto; min-width: 0; }

.view-banner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 8px 16px;
  padding: 10px 14px;
  border-radius: 8px;
  background: var(--accent-soft);
  font-size: 14px;
  overflow-wrap: anywhere;
}

.view-timer { font-family: var(--mono); font-variant-numeric: tabular-nums; }

.mail-list {
  border: 1px solid var(--line);
  border-radius: 8px;
  overflow: hidden;
}

.mail-list-header {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 4px 12px;
  padding: 12px 14px;
  border-bottom: 1px solid var(--line);
}

.mail-list-header h3 { font-size: 16px; font-weight: 700; }

.count { color: var(--muted); font-weight: 500; }

.status {
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--muted);
  font-size: 13px;
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent);
  animation: pulse 2s ease-in-out infinite;
}

.status[data-state="off"] .status-dot { background: var(--muted); animation: none; }
.status[data-state="error"] .status-dot { background: var(--danger); animation: none; }

@keyframes pulse { 50% { opacity: .35; } }

@media (prefers-reduced-motion: reduce) {
  .status-dot { animation: none; }
  .meter-fill { transition: none; }
}

.message-list { max-height: 420px; overflow-y: auto; }

.message-item {
  display: grid;
  grid-template-areas: "from subject time";
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.5fr) auto;
  align-items: baseline;
  gap: 12px;
  width: 100%;
  padding: 13px 14px;
  border: 0;
  border-bottom: 1px solid var(--line);
  background: transparent;
  color: inherit;
  font: 14px/1.4 var(--sans);
  text-align: left;
  cursor: pointer;
}

.message-list li:last-child .message-item { border-bottom: 0; }

.message-item:hover { background: var(--surface-hover); }

.message-item[aria-current="true"] { background: var(--accent-soft); }

.message-item-from,
.message-item-subject {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.message-item-from { grid-area: from; }

.message-item-subject { grid-area: subject; }

.message-item-time {
  grid-area: time;
  color: var(--muted);
  font-size: 13px;
  white-space: nowrap;
}

.message-item.unread .message-item-from,
.message-item.unread .message-item-subject { font-weight: 700; }

.empty {
  display: grid;
  align-content: center;
  justify-items: center;
  gap: 4px;
  min-height: 150px;
  padding: 20px;
  color: var(--muted);
  font-size: 14px;
  text-align: center;
}

.empty-title { color: var(--ink); font-size: 15px; font-weight: 600; }

.message { gap: 8px; }

.message-toolbar { display: flex; justify-content: space-between; gap: 8px; }

.message-subject { overflow-wrap: anywhere; }

.message-subject:focus { outline: none; }

.message-meta { color: var(--muted); font-size: 13px; overflow-wrap: anywhere; }

.message-body { margin-top: 8px; }

.message-frame {
  display: block;
  width: 100%;
  height: min(68vh, 640px);
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #ffffff;
}

.message-text {
  margin: 0;
  font: 14px/1.55 var(--sans);
  white-space: pre-wrap;
  overflow-wrap: anywhere;
}

.message-text a { color: var(--accent); }

.attachments { display: grid; gap: 4px; margin-top: 8px; font-size: 14px; }

.attachments li { overflow-wrap: anywhere; }

.site-footer {
  padding-block: 20px 32px;
  color: var(--muted);
  font-size: 13px;
}

@media (max-width: 559px) {
  .card-body { padding: 18px; }

  .message-item {
    grid-template-areas:
      "from time"
      "subject subject";
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 2px 12px;
  }
}

@media (min-width: 620px) {
  .create-form {
    grid-template-columns: minmax(0, 1.2fr) auto minmax(0, 1fr);
    align-items: end;
    gap: 16px 10px;
  }

  .at {
    display: block;
    padding-bottom: 10px;
    color: var(--muted);
    font: 600 20px var(--mono);
  }

  .form-actions { grid-column: 1 / -1; }
}

@media (min-width: 900px) {
  .columns { grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); }
}