:root {
  --accent: #6c5ce7;
  --accent-soft: #8a7bf0;
  --accent-ghost: rgba(108, 92, 231, 0.1);
  --accent-grad: linear-gradient(135deg, #7b6ef0 0%, #6c5ce7 100%);

  --bg: #eef0f7;
  --surface: #ffffff;
  --surface-2: #f6f7fb;
  --surface-hover: #f0f1f8;
  --border: #e6e8f0;

  --text: #1f2233;
  --text-soft: #6b7089;
  --text-faint: #9aa0b8;

  --danger: #e74c6c;
  --success: #22b07d;

  --radius-lg: 26px;
  --radius: 18px;
  --radius-sm: 12px;
  --shadow: 0 10px 40px rgba(38, 42, 80, 0.08);
  --shadow-soft: 0 4px 18px rgba(38, 42, 80, 0.06);

  --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto,
    Helvetica, Arial, sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14151f;
    --surface: #1d1e2b;
    --surface-2: #242536;
    --surface-hover: #2a2c40;
    --border: #2e3044;
    --text: #eef0f7;
    --text-soft: #a6abc4;
    --text-faint: #6f748f;
    --accent-ghost: rgba(138, 123, 240, 0.16);
    --shadow: 0 12px 44px rgba(0, 0, 0, 0.4);
    --shadow-soft: 0 4px 18px rgba(0, 0, 0, 0.3);
  }
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html,
body {
  height: 100%;
}

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  -webkit-font-smoothing: antialiased;
  overflow: hidden;
}

.hidden {
  display: none !important;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
  color: inherit;
}

input,
textarea {
  font-family: inherit;
}

/* ---------------- Buttons ---------------- */

.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background: var(--accent-grad);
  color: #fff;
  border-radius: 999px;
  padding: 12px 22px;
  font-weight: 600;
  font-size: 15px;
  box-shadow: 0 6px 18px rgba(108, 92, 231, 0.35);
  transition: transform 0.12s ease, box-shadow 0.12s ease, opacity 0.12s ease;
}
.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 10px 24px rgba(108, 92, 231, 0.42);
}
.btn-primary:active {
  transform: translateY(0);
}
.btn-primary:disabled {
  opacity: 0.6;
  cursor: default;
  transform: none;
}
.btn-block {
  width: 100%;
}
.btn-ghost {
  border-radius: 999px;
  padding: 12px 20px;
  font-weight: 600;
  color: var(--text-soft);
  transition: background 0.12s ease;
}
.btn-ghost:hover {
  background: var(--surface-hover);
}

.icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 999px;
  color: var(--text-soft);
  transition: background 0.12s ease, color 0.12s ease;
}
.icon-btn:hover {
  background: var(--surface-hover);
  color: var(--text);
}

.brand-badge {
  width: 56px;
  height: 56px;
  border-radius: 20px;
  background: var(--accent-grad);
  display: grid;
  place-items: center;
  font-size: 28px;
  box-shadow: 0 8px 20px rgba(108, 92, 231, 0.4);
}
.brand-badge.small {
  width: 38px;
  height: 38px;
  border-radius: 12px;
  font-size: 20px;
}

/* ---------------- Login ---------------- */

.login-view {
  height: 100%;
  display: grid;
  place-items: center;
  padding: 24px;
  background: radial-gradient(
      1200px 600px at 10% -10%,
      rgba(108, 92, 231, 0.16),
      transparent
    ),
    radial-gradient(1000px 500px at 110% 110%, rgba(34, 176, 125, 0.12), transparent),
    var(--bg);
  overflow: auto;
}

.login-card {
  width: 100%;
  max-width: 460px;
  background: var(--surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  padding: 40px 38px;
}
.login-card.wide {
  max-width: 520px;
}
.field-hint {
  font-size: 12px;
  color: var(--text-faint);
  line-height: 1.4;
  margin-top: 2px;
}
.resend-box {
  padding: 6px 0 12px;
}
.resend-box .field {
  margin-top: 8px;
}
.server-grid.one {
  grid-template-columns: 1fr;
}

.login-brand {
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  margin-bottom: 26px;
}
.login-brand h1 {
  font-size: 26px;
  font-weight: 700;
  letter-spacing: -0.5px;
}
.login-brand p {
  color: var(--text-soft);
  font-size: 14px;
}

.preset-row {
  display: flex;
  gap: 8px;
  margin-bottom: 22px;
}
.preset {
  flex: 1;
  padding: 9px 0;
  border-radius: var(--radius-sm);
  background: var(--surface-2);
  color: var(--text-soft);
  font-weight: 600;
  font-size: 13px;
  border: 1.5px solid transparent;
  transition: all 0.12s ease;
}
.preset:hover {
  color: var(--text);
  border-color: var(--border);
}
.preset.active {
  color: var(--accent);
  background: var(--accent-ghost);
  border-color: var(--accent);
}

.login-form {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.field > span {
  font-size: 13px;
  font-weight: 600;
  color: var(--text-soft);
}
.field input[type='text'],
.field input[type='email'],
.field input[type='password'],
.field input[type='number'] {
  background: var(--surface-2);
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  font-size: 15px;
  color: var(--text);
  transition: border 0.12s ease, box-shadow 0.12s ease;
  width: 100%;
}
.field input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 4px var(--accent-ghost);
}
.field.checkbox {
  flex-direction: row;
  align-items: center;
  gap: 8px;
  padding-top: 22px;
}
.field.checkbox input {
  width: 18px;
  height: 18px;
  accent-color: var(--accent);
}
.field.checkbox span {
  font-size: 13px;
}

.row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.advanced {
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  padding: 4px 16px;
  background: var(--surface-2);
}
.advanced summary {
  cursor: pointer;
  font-size: 13px;
  font-weight: 600;
  color: var(--text-soft);
  padding: 10px 0;
  list-style: none;
}
.advanced summary::-webkit-details-marker {
  display: none;
}
.advanced summary::before {
  content: '⚙  ';
}
.server-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  padding: 8px 0 14px;
}
.server-col h3 {
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--text-faint);
  margin-bottom: 10px;
}
.server-col .field {
  margin-bottom: 10px;
}

.login-error,
.compose-error {
  background: rgba(231, 76, 108, 0.12);
  color: var(--danger);
  border-radius: var(--radius-sm);
  padding: 10px 14px;
  font-size: 13px;
  font-weight: 500;
}

.diag-btn {
  margin-top: -6px;
  font-size: 13px;
}
.diag-result {
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-size: 13px;
  color: var(--text-soft);
}
.diag-result:empty {
  display: none;
}
.diag-row {
  display: flex;
  flex-direction: column;
  gap: 2px;
  background: var(--surface-2);
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 10px 14px;
}
.diag-row.ok {
  border-color: rgba(34, 176, 125, 0.5);
}
.diag-row.fail {
  border-color: rgba(231, 76, 108, 0.5);
}
.diag-row strong {
  font-size: 13px;
  color: var(--text);
}
.diag-dns {
  font-size: 11px;
  color: var(--text-faint);
}

.resend-note {
  background: var(--accent-ghost);
  color: var(--accent);
  border-radius: var(--radius-sm);
  padding: 11px 14px;
  font-size: 13px;
  line-height: 1.5;
}

.login-note {
  margin-top: 18px;
  text-align: center;
  font-size: 12px;
  color: var(--text-faint);
  line-height: 1.5;
}

/* ---------------- App layout ---------------- */

.app-view {
  height: 100%;
  display: grid;
  grid-template-columns: 250px 380px 1fr;
}

.sidebar {
  background: var(--surface);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  padding: 20px 16px;
  gap: 18px;
}
.sidebar-top {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 0 6px;
}
.sidebar-title {
  font-weight: 700;
  font-size: 18px;
  letter-spacing: -0.3px;
}
.compose-btn {
  width: 100%;
}

.folders {
  display: flex;
  flex-direction: column;
  gap: 3px;
  flex: 1;
  overflow-y: auto;
  margin: 0 -4px;
  padding: 0 4px;
}
.folder {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 11px 14px;
  border-radius: 14px;
  color: var(--text-soft);
  font-weight: 500;
  font-size: 14px;
  transition: background 0.12s ease, color 0.12s ease;
  text-align: left;
}
.folder:hover {
  background: var(--surface-hover);
  color: var(--text);
}
.folder.active {
  background: var(--accent-ghost);
  color: var(--accent);
  font-weight: 600;
}
.folder .folder-icon {
  width: 20px;
  text-align: center;
  flex-shrink: 0;
}
.folder .folder-name {
  flex: 1;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.sidebar-footer {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 10px 0;
  border-top: 1px solid var(--border);
}
.user-email {
  flex: 1;
  font-size: 12px;
  color: var(--text-faint);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* ---------------- Message list ---------------- */

.mail-list-pane {
  background: var(--surface-2);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  min-width: 0;
}
.list-header {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 18px 20px;
}
.list-header h2 {
  font-size: 19px;
  font-weight: 700;
  letter-spacing: -0.3px;
  white-space: nowrap;
}
.search-box {
  flex: 1;
  display: flex;
  align-items: center;
  gap: 8px;
  background: var(--surface);
  border: 1.5px solid var(--border);
  border-radius: 999px;
  padding: 8px 14px;
  color: var(--text-faint);
  min-width: 0;
}
.search-box input {
  border: none;
  background: none;
  outline: none;
  color: var(--text);
  font-size: 14px;
  width: 100%;
}

.message-list {
  flex: 1;
  overflow-y: auto;
  padding: 4px 12px 12px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.msg-card {
  background: var(--surface);
  border-radius: var(--radius);
  padding: 14px 16px;
  cursor: pointer;
  border: 1.5px solid transparent;
  transition: border 0.12s ease, transform 0.1s ease, box-shadow 0.12s ease;
  position: relative;
}
.msg-card:hover {
  box-shadow: var(--shadow-soft);
  transform: translateY(-1px);
}
.msg-card.active {
  border-color: var(--accent);
}
.msg-card.unread::before {
  content: '';
  position: absolute;
  left: 6px;
  top: 50%;
  transform: translateY(-50%);
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--accent);
}
.msg-card.unread .msg-from,
.msg-card.unread .msg-subject {
  font-weight: 700;
}
.msg-row {
  display: flex;
  align-items: baseline;
  gap: 8px;
}
.msg-from {
  font-weight: 600;
  font-size: 14px;
  flex: 1;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.msg-date {
  font-size: 12px;
  color: var(--text-faint);
  flex-shrink: 0;
}
.msg-subject {
  font-size: 13.5px;
  color: var(--text);
  margin-top: 3px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.msg-preview {
  font-size: 12.5px;
  color: var(--text-faint);
  margin-top: 2px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.msg-badges {
  position: absolute;
  right: 14px;
  bottom: 12px;
  display: flex;
  gap: 4px;
  font-size: 12px;
}

.list-pager {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 14px;
  padding: 12px;
  font-size: 13px;
  color: var(--text-soft);
}
.list-pager button {
  border-radius: 999px;
  padding: 7px 16px;
  background: var(--surface);
  border: 1.5px solid var(--border);
  font-weight: 600;
  transition: all 0.12s ease;
}
.list-pager button:hover:not(:disabled) {
  border-color: var(--accent);
  color: var(--accent);
}
.list-pager button:disabled {
  opacity: 0.4;
  cursor: default;
}

.empty-state,
.loading-state {
  text-align: center;
  color: var(--text-faint);
  padding: 60px 20px;
  font-size: 14px;
}

/* ---------------- Reader ---------------- */

.reader-pane {
  background: var(--surface);
  display: flex;
  flex-direction: column;
  min-width: 0;
}
.reader-empty {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 12px;
  color: var(--text-faint);
}
.reader-empty-icon {
  font-size: 54px;
  opacity: 0.6;
}

.reader {
  flex: 1;
  overflow-y: auto;
  padding: 30px 40px;
}
.reader-subject {
  font-size: 24px;
  font-weight: 700;
  letter-spacing: -0.4px;
  line-height: 1.3;
  margin-bottom: 20px;
}
.reader-meta {
  display: flex;
  align-items: center;
  gap: 14px;
  padding-bottom: 20px;
  margin-bottom: 24px;
  border-bottom: 1px solid var(--border);
}
.reader-avatar {
  width: 46px;
  height: 46px;
  border-radius: 16px;
  background: var(--accent-grad);
  color: #fff;
  display: grid;
  place-items: center;
  font-weight: 700;
  font-size: 18px;
  flex-shrink: 0;
}
.reader-meta-text {
  flex: 1;
  min-width: 0;
}
.reader-from {
  font-weight: 600;
  font-size: 15px;
}
.reader-to {
  font-size: 13px;
  color: var(--text-soft);
  margin-top: 2px;
}
.reader-date {
  font-size: 13px;
  color: var(--text-faint);
  flex-shrink: 0;
}
.reader-actions {
  display: flex;
  gap: 8px;
  margin-bottom: 24px;
}
.reader-body {
  font-size: 15px;
  line-height: 1.65;
  color: var(--text);
  word-wrap: break-word;
  overflow-wrap: break-word;
}
.reader-body p {
  margin: 0 0 1em;
}
.reader-body a {
  color: var(--accent);
}
.reader-body img {
  max-width: 100%;
  height: auto;
  border-radius: 8px;
}
.reader-body iframe {
  width: 100%;
  border: none;
  border-radius: var(--radius-sm);
  background: #fff;
}
.reader-text {
  white-space: pre-wrap;
  font-family: var(--font);
}
.attachments {
  margin-top: 26px;
  padding-top: 20px;
  border-top: 1px solid var(--border);
}
.attachments h4 {
  font-size: 13px;
  color: var(--text-soft);
  margin-bottom: 10px;
}
.attach-list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}
.attach-chip {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--surface-2);
  border: 1.5px solid var(--border);
  border-radius: 999px;
  padding: 8px 16px;
  font-size: 13px;
  font-weight: 500;
  color: var(--text);
  transition: border 0.12s ease;
  text-decoration: none;
}
.attach-chip:hover {
  border-color: var(--accent);
}

/* ---------------- Compose ---------------- */

.compose-overlay {
  position: fixed;
  inset: 0;
  background: rgba(20, 21, 31, 0.4);
  backdrop-filter: blur(4px);
  display: grid;
  place-items: end center;
  padding: 0 40px 0 0;
  z-index: 50;
}
.compose-window {
  width: 100%;
  max-width: 560px;
  height: min(620px, 90vh);
  background: var(--surface);
  border-radius: var(--radius-lg) var(--radius-lg) 0 0;
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
  animation: slideUp 0.22s ease;
}
@keyframes slideUp {
  from {
    transform: translateY(30px);
    opacity: 0;
  }
  to {
    transform: translateY(0);
    opacity: 1;
  }
}
.compose-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 20px;
  border-bottom: 1px solid var(--border);
  font-weight: 700;
  font-size: 15px;
}
.compose-form {
  flex: 1;
  display: flex;
  flex-direction: column;
  padding: 8px 20px 20px;
  min-height: 0;
}
.compose-field {
  display: flex;
  align-items: center;
  gap: 12px;
  border-bottom: 1px solid var(--border);
  padding: 12px 4px;
}
.compose-field span {
  font-size: 13px;
  font-weight: 600;
  color: var(--text-soft);
  width: 52px;
}
.compose-field input {
  flex: 1;
  border: none;
  background: none;
  outline: none;
  font-size: 14px;
  color: var(--text);
}
.compose-form textarea {
  flex: 1;
  border: none;
  background: none;
  outline: none;
  resize: none;
  padding: 16px 4px;
  font-size: 15px;
  line-height: 1.6;
  color: var(--text);
  min-height: 120px;
}
.compose-actions {
  display: flex;
  align-items: center;
  gap: 10px;
  padding-top: 8px;
}

/* ---------------- Toast ---------------- */

.toast {
  position: fixed;
  bottom: 28px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--text);
  color: var(--surface);
  padding: 13px 24px;
  border-radius: 999px;
  font-size: 14px;
  font-weight: 500;
  box-shadow: var(--shadow);
  z-index: 100;
  animation: toastIn 0.2s ease;
}
.toast.error {
  background: var(--danger);
  color: #fff;
}
.toast.success {
  background: var(--success);
  color: #fff;
}
@keyframes toastIn {
  from {
    transform: translate(-50%, 12px);
    opacity: 0;
  }
  to {
    transform: translate(-50%, 0);
    opacity: 1;
  }
}

.spinner {
  width: 18px;
  height: 18px;
  border: 2.5px solid rgba(255, 255, 255, 0.4);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}
@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

/* ---------------- Responsive ---------------- */

@media (max-width: 1000px) {
  .app-view {
    grid-template-columns: 72px 1fr;
  }
  .sidebar-title,
  .compose-btn span,
  .user-email {
    display: none;
  }
  .compose-btn {
    padding: 12px;
  }
  .folder-name {
    display: none;
  }
  .reader-pane {
    display: none;
  }
  .reader-pane.mobile-active {
    display: flex;
    position: fixed;
    inset: 0;
    z-index: 40;
  }
}