:root {
  color-scheme: dark;
  --bg: #0c111d;
  --panel: rgba(12, 17, 29, 0.84);
  --panel-strong: #131a29;
  --line: rgba(148, 163, 184, 0.18);
  --line-strong: rgba(148, 163, 184, 0.3);
  --text: #eef2ff;
  --muted: #9aa7bf;
  --primary: #7c9cff;
  --primary-strong: #5b7eff;
  --success: #3dd9b1;
  --warning: #ffca75;
  --shadow: 0 24px 48px rgba(0, 0, 0, 0.28);
  --radius: 22px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Segoe UI", "PingFang SC", sans-serif;
  background:
    radial-gradient(circle at top left, rgba(124, 156, 255, 0.22), transparent 30%),
    radial-gradient(circle at top right, rgba(61, 217, 177, 0.16), transparent 22%),
    linear-gradient(160deg, #0b1020 0%, #101829 100%);
  color: var(--text);
}

button,
input {
  font: inherit;
}

.hidden {
  display: none !important;
}

.app-shell {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 20px;
  min-height: 100vh;
  padding: 20px;
}

.card,
.settings-dialog::backdrop {
  backdrop-filter: blur(18px);
}

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

.sidebar {
  display: flex;
  flex-direction: column;
  gap: 18px;
  padding: 20px;
}

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

.brand__logo {
  display: grid;
  place-items: center;
  width: 52px;
  height: 52px;
  border-radius: 18px;
  background: linear-gradient(135deg, var(--primary), #47d0ff);
  font-size: 26px;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.22);
}

.brand h1,
.panel-header h2,
.settings-form h2 {
  margin: 0;
}

.brand p,
.panel-header p,
.detail-empty p,
.settings-form p,
.detail-date,
.section-title span,
.status-pill,
.badge,
.toggle span,
.mailbox-item__meta,
.email-item__meta,
.empty-state p {
  color: var(--muted);
}

.button,
.icon-button {
  border: 0;
  cursor: pointer;
}

.button {
  padding: 10px 16px;
  border-radius: 14px;
  transition: transform 0.16s ease, opacity 0.16s ease, background 0.16s ease;
}

.button:hover,
.icon-button:hover {
  transform: translateY(-1px);
}

.button--primary {
  background: linear-gradient(135deg, var(--primary), var(--primary-strong));
  color: white;
}

.button--secondary,
.button--ghost,
.icon-button,
.search-input,
.settings-form input {
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
  border: 1px solid var(--line);
}

.button--ghost,
.button--secondary {
  color: var(--text);
}

.button--full {
  width: 100%;
}

.icon-button {
  width: 36px;
  height: 36px;
  border-radius: 12px;
}

.sidebar__section,
.workspace,
.mail-list,
.mail-detail {
  display: flex;
  flex-direction: column;
}

.section-title,
.panel-header,
.toolbar,
.detail-card__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.mailbox-list,
.attachments-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.mailbox-item,
.email-item {
  width: 100%;
  text-align: left;
  border-radius: 18px;
  border: 1px solid transparent;
  background: rgba(255, 255, 255, 0.03);
  color: var(--text);
  cursor: pointer;
  transition: border-color 0.16s ease, background 0.16s ease, transform 0.16s ease;
}

.mailbox-item {
  padding: 14px 16px;
}

.mailbox-item:hover,
.mailbox-item.is-active,
.email-item:hover,
.email-item.is-active {
  border-color: rgba(124, 156, 255, 0.5);
  background: rgba(124, 156, 255, 0.12);
}

.mailbox-item__name,
.email-item__subject,
.detail-card h3 {
  font-weight: 700;
}

.mailbox-item__meta,
.email-item__meta {
  display: flex;
  justify-content: space-between;
  gap: 8px;
  margin-top: 6px;
  font-size: 12px;
}

.workspace {
  gap: 20px;
}

.toolbar {
  padding: 18px 20px;
}

.toolbar__left,
.toolbar__right,
.detail-actions,
.settings-actions,
.detail-meta-row,
.tabs {
  display: flex;
  align-items: center;
  gap: 10px;
}

.search-input,
.settings-form input {
  width: min(380px, 100%);
  padding: 11px 14px;
  border-radius: 14px;
  outline: none;
}

.toggle {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.status-pill,
.badge {
  display: inline-flex;
  align-items: center;
  padding: 6px 10px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.04);
  font-size: 12px;
}

.status-pill.is-online {
  color: var(--success);
  border-color: rgba(61, 217, 177, 0.35);
}

.content-grid {
  display: grid;
  grid-template-columns: minmax(320px, 420px) 1fr;
  gap: 20px;
  min-height: 0;
  flex: 1;
}

.mail-list,
.mail-detail {
  min-height: 0;
  padding: 18px;
}

.email-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
  overflow: auto;
  padding-right: 4px;
}

.email-item {
  padding: 16px;
}

.email-item__top,
.email-item__bottom {
  display: flex;
  justify-content: space-between;
  gap: 12px;
}

.email-item__snippet {
  margin: 10px 0 0;
  color: var(--muted);
  line-height: 1.5;
}

.email-item__flags {
  display: flex;
  gap: 8px;
  align-items: center;
}

.dot {
  width: 10px;
  height: 10px;
  border-radius: 999px;
  background: var(--warning);
}

.dot.is-read {
  background: rgba(255, 255, 255, 0.16);
}

.star {
  color: #ffd166;
}

.empty-state,
.detail-empty {
  display: grid;
  place-items: center;
  text-align: center;
  min-height: 320px;
  border: 1px dashed var(--line-strong);
  border-radius: 22px;
}

.detail-card {
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.detail-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px 18px;
  margin: 0;
  padding: 16px;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.03);
}

.detail-grid dt {
  color: var(--muted);
  font-size: 12px;
  margin-bottom: 6px;
}

.detail-grid dd {
  margin: 0;
  line-height: 1.5;
}

.tabs {
  flex-wrap: wrap;
}

.tab {
  padding: 10px 14px;
  border-radius: 12px;
  color: var(--muted);
  background: transparent;
  border: 1px solid var(--line);
}

.tab.is-active {
  color: white;
  background: rgba(124, 156, 255, 0.16);
  border-color: rgba(124, 156, 255, 0.5);
}

.tab-panel {
  min-height: 420px;
}

#html-frame,
.pre-panel {
  width: 100%;
  min-height: 420px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.03);
}

#html-frame {
  background: white;
}

.pre-panel {
  margin: 0;
  padding: 16px;
  color: var(--text);
  white-space: pre-wrap;
  overflow: auto;
}

.attachment-card {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  padding: 14px 16px;
  border-radius: 16px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.03);
}

.settings-dialog {
  width: min(560px, calc(100vw - 24px));
  padding: 0;
  border: 1px solid var(--line);
  border-radius: 24px;
  background: var(--panel-strong);
  color: var(--text);
}

.settings-dialog::backdrop {
  background: rgba(0, 0, 0, 0.5);
}

.settings-form {
  display: flex;
  flex-direction: column;
  gap: 18px;
  padding: 24px;
}

.settings-form label {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.settings-form__header {
  display: flex;
  align-items: start;
  justify-content: space-between;
  gap: 16px;
}

@media (max-width: 1180px) {
  .app-shell,
  .content-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 760px) {
  .app-shell {
    padding: 14px;
  }

  .toolbar,
  .toolbar__left,
  .toolbar__right,
  .detail-actions,
  .detail-grid {
    flex-direction: column;
    align-items: stretch;
  }

  .search-input,
  .settings-form input {
    width: 100%;
  }
}