:root {
  --bg: #f4f1ff;
  --bg-deep: #ebe6ff;
  --paper: rgba(255, 255, 255, 0.72);
  --paper-solid: #ffffff;
  --ink: #1f2328;
  --ink-2: #424a53;
  --mute: #656d76;
  --line: rgba(31, 35, 40, 0.12);
  --line-soft: rgba(31, 35, 40, 0.08);
  --accent: #6d4aff;
  --accent-2: #8b6cff;
  --accent-soft: rgba(109, 74, 255, 0.12);
  --fill: #6d4aff;
  --fill-text: #ffffff;
  --fill-hover: #5b3ae6;
  --danger: #cf222e;
  --sidebar: rgba(246, 248, 250, 0.9);
  --glass: rgba(255, 255, 255, 0.55);
  --glass-border: rgba(255, 255, 255, 0.65);
  --shadow: 0 12px 40px rgba(88, 60, 180, 0.1);
  --radius: 12px;
  --radius-sm: 8px;
  --font-brand: "Segoe UI", "Helvetica Neue", Arial, sans-serif;
  --font-ui: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans", Helvetica, Arial, sans-serif;
  --nav-h: 64px;
  --ease: cubic-bezier(0.2, 0.8, 0.2, 1);
}

*,
*::before,
*::after { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font-ui);
  color: var(--ink);
  background:
    radial-gradient(900px 480px at 12% -10%, rgba(109, 74, 255, 0.18), transparent 55%),
    radial-gradient(700px 420px at 88% 8%, rgba(96, 160, 255, 0.14), transparent 50%),
    radial-gradient(600px 360px at 70% 90%, rgba(109, 74, 255, 0.08), transparent 55%),
    linear-gradient(180deg, #f7f5ff 0%, #f3f6fa 45%, #eef2f7 100%);
  background-attachment: fixed;
  line-height: 1.55;
  font-size: 15px;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
button, input, textarea, select { font: inherit; color: inherit; }

.container {
  width: min(1120px, calc(100% - 40px));
  margin-inline: auto;
}

.site-nav {
  position: sticky;
  top: 0;
  z-index: 40;
  height: var(--nav-h);
  display: flex;
  align-items: center;
  background: rgba(255, 255, 255, 0.58);
  backdrop-filter: blur(18px) saturate(160%);
  -webkit-backdrop-filter: blur(18px) saturate(160%);
  border-bottom: 1px solid var(--glass-border);
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.4);
}

.site-nav .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.brand { display: inline-flex; align-items: center; line-height: 0; }
.brand img,
.brand svg {
  height: 30px;
  width: auto;
  aspect-ratio: 864 / 445;
  object-fit: contain;
  flex-shrink: 0;
}

.nav-links {
  display: flex;
  gap: 24px;
  font-size: 14px;
  font-weight: 500;
  color: var(--ink-2);
}

.nav-links a:hover { color: var(--accent); }
.nav-actions { display: flex; gap: 10px; align-items: center; }

.lang-select {
  min-height: 36px;
  padding: 0 10px;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.75);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  color: var(--ink-2);
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
}
.lang-select:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  min-height: 38px;
  padding: 0 16px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.7);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  color: var(--ink);
  cursor: pointer;
  border-radius: var(--radius-sm);
  transition: background 0.18s var(--ease), border-color 0.18s, box-shadow 0.18s, transform 0.18s;
  white-space: nowrap;
  font-size: 14px;
  font-weight: 600;
}

.btn:hover {
  background: #fff;
  border-color: rgba(109, 74, 255, 0.28);
  box-shadow: 0 4px 14px rgba(109, 74, 255, 0.12);
}

.btn-primary {
  background: linear-gradient(180deg, var(--accent-2), var(--accent));
  color: var(--fill-text);
  border-color: transparent;
  box-shadow: 0 6px 18px rgba(109, 74, 255, 0.28);
}

.btn-primary:hover {
  background: var(--fill-hover);
  border-color: transparent;
  box-shadow: 0 8px 22px rgba(109, 74, 255, 0.34);
}

.btn-ghost {
  border-color: transparent;
  background: transparent;
  backdrop-filter: none;
}

.btn-ghost:hover { background: var(--accent-soft); box-shadow: none; }
.btn-block { width: 100%; }
.btn-lg { min-height: 46px; padding: 0 22px; font-size: 15px; border-radius: 10px; }

.hero {
  min-height: calc(100vh - var(--nav-h));
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  align-items: stretch;
  border-bottom: 1px solid var(--line-soft);
}

.hero-copy {
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: clamp(48px, 8vw, 96px) clamp(24px, 6vw, 72px);
}

.hero-logo {
  display: block;
  width: 100px;
  object-fit: contain;
  object-position: left center;
  margin: 0 0 28px;
}

.hero h1 {
  margin: 0 0 16px;
  font-family: var(--font-brand);
  font-weight: 700;
  font-size: clamp(2.1rem, 4.4vw, 3.35rem);
  line-height: 1.12;
  letter-spacing: -0.035em;
  max-width: 14ch;
  color: var(--ink);
}

.hero .lead {
  margin: 0 0 28px;
  max-width: 38ch;
  color: var(--mute);
  font-size: 1.08rem;
  line-height: 1.6;
}

.hero-cta { display: flex; flex-wrap: wrap; gap: 12px; }

.hero-stage {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 40px 28px;
}

.ui-frame {
  width: min(460px, 100%);
  background: rgba(255, 255, 255, 0.62);
  backdrop-filter: blur(22px) saturate(170%);
  -webkit-backdrop-filter: blur(22px) saturate(170%);
  border: 1px solid rgba(255, 255, 255, 0.7);
  border-radius: 16px;
  box-shadow: var(--shadow), inset 0 1px 0 rgba(255, 255, 255, 0.8);
  overflow: hidden;
}

.ui-frame-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 14px;
  border-bottom: 1px solid var(--line-soft);
  font-size: 12px;
  color: var(--mute);
  background: rgba(255, 255, 255, 0.35);
}

.ui-frame-body {
  display: grid;
  grid-template-columns: 108px 1fr;
  min-height: 290px;
}

.ui-side {
  border-right: 1px solid var(--line-soft);
  background: rgba(246, 248, 250, 0.55);
  padding: 12px 8px;
  font-size: 12px;
  color: var(--ink-2);
}

.ui-side div {
  padding: 8px 10px;
  margin-bottom: 4px;
  border-radius: 8px;
}

.ui-side .on {
  background: var(--accent);
  color: #fff;
  font-weight: 600;
}

.ui-list { padding: 0; }
.ui-row {
  padding: 12px 14px;
  border-bottom: 1px solid var(--line-soft);
}
.ui-row strong { display: block; font-size: 13px; margin-bottom: 3px; }
.ui-row span { font-size: 12px; color: var(--mute); }

.section {
  padding: 88px 0;
  border-bottom: 1px solid var(--line-soft);
}

.section-head {
  max-width: 560px;
  margin-bottom: 36px;
}

.section-head h2 {
  margin: 0 0 12px;
  font-family: var(--font-brand);
  font-weight: 700;
  font-size: clamp(1.7rem, 2.8vw, 2.25rem);
  letter-spacing: -0.03em;
}

.section-head p {
  margin: 0;
  color: var(--mute);
  font-size: 1.02rem;
}

.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.split article {
  padding: 24px;
  border: 1px solid var(--glass-border);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.55);
  backdrop-filter: blur(16px) saturate(150%);
  -webkit-backdrop-filter: blur(16px) saturate(150%);
  box-shadow: 0 8px 24px rgba(88, 60, 180, 0.05);
}

.split h3 {
  margin: 0 0 8px;
  font-size: 1.02rem;
  font-weight: 650;
}

.split p {
  margin: 0;
  color: var(--mute);
  font-size: 0.95rem;
}

.cta-strip {
  padding: 72px 24px;
  border-bottom: 1px solid var(--line-soft);
}

.cta-strip .container {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 24px;
  align-items: center;
  padding: 28px 32px;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.5);
  backdrop-filter: blur(20px) saturate(160%);
  -webkit-backdrop-filter: blur(20px) saturate(160%);
  border: 1px solid var(--glass-border);
  box-shadow: var(--shadow);
}

.cta-strip h2 {
  margin: 0 0 6px;
  font-family: var(--font-brand);
  font-weight: 700;
  font-size: clamp(1.5rem, 2.4vw, 1.9rem);
  letter-spacing: -0.03em;
}

.cta-strip p { margin: 0; color: var(--mute); }

.site-footer {
  padding: 36px 0 48px;
}

.footer-grid {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 16px;
  align-items: center;
}

.footer-grid img { height: 26px; width: auto; aspect-ratio: 864 / 445; object-fit: contain; }
.footer-meta { margin: 0; color: var(--mute); font-size: 13px; }
.footer-links { display: flex; gap: 18px; font-size: 14px; color: var(--ink-2); }
.footer-links a:hover { color: var(--accent); }

.auth-page {
  min-height: 100vh;
  display: grid;
  grid-template-columns: 0.95fr 1.05fr;
}

.auth-visual {
  background:
    radial-gradient(600px 360px at 20% 20%, rgba(255, 255, 255, 0.18), transparent 55%),
    linear-gradient(160deg, #5b3ae6 0%, #6d4aff 45%, #3d2a8a 100%);
  color: #fff;
  padding: 36px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.auth-visual .brand img {
  filter: invert(1);
  height: 36px;
  width: auto;
  aspect-ratio: 864 / 445;
  object-fit: contain;
}

.auth-quote h2 {
  margin: 0 0 12px;
  font-family: var(--font-brand);
  font-weight: 700;
  font-size: clamp(1.8rem, 3vw, 2.4rem);
  line-height: 1.2;
  letter-spacing: -0.03em;
  max-width: 14ch;
}

.auth-quote p { margin: 0; color: rgba(255, 255, 255, 0.78); max-width: 32ch; }

.auth-panel {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 40px 20px;
}

.auth-card {
  width: min(420px, 100%);
  padding: 28px;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.62);
  backdrop-filter: blur(20px) saturate(160%);
  -webkit-backdrop-filter: blur(20px) saturate(160%);
  border: 1px solid var(--glass-border);
  box-shadow: var(--shadow);
}

.auth-card h1 {
  margin: 0 0 6px;
  font-family: var(--font-brand);
  font-weight: 700;
  font-size: 1.85rem;
  letter-spacing: -0.03em;
}

.auth-card .sub { margin: 0 0 22px; color: var(--mute); }

.form-group { margin-bottom: 14px; }
.form-group label {
  display: block;
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 6px;
  color: var(--ink-2);
}

.form-group input,
.form-group textarea,
.form-group select,
.compose-field input,
.compose-field textarea,
.search-box input {
  width: 100%;
  min-height: 42px;
  padding: 8px 12px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.85);
  border-radius: var(--radius-sm);
  outline: none;
}

.form-group input:focus,
.form-group textarea:focus,
.compose-field input:focus,
.search-box input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

.form-hint {
  margin-top: 16px;
  font-size: 13px;
  color: var(--mute);
  text-align: center;
}

.form-hint a {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 2px;
}

.domain-suffix { display: flex; align-items: stretch; }
.domain-suffix input {
  border-right: none;
  border-radius: var(--radius-sm) 0 0 var(--radius-sm);
}
.domain-suffix span {
  display: inline-flex;
  align-items: center;
  padding: 0 12px;
  border: 1px solid var(--line);
  background: rgba(246, 248, 250, 0.9);
  color: var(--mute);
  font-size: 13px;
  white-space: nowrap;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

.mail-app {
  height: 100vh;
  display: grid;
  grid-template-columns: 228px 330px 1fr;
  background: #f6f8fa;
  overflow: hidden;
}

.mail-sidebar {
  border-right: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.72);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  display: flex;
  flex-direction: column;
  padding: 14px 10px;
}

.mail-sidebar .brand { padding: 6px 8px 14px; }
.mail-sidebar .brand img { height: 28px; width: auto; aspect-ratio: 864 / 445; object-fit: contain; }
.compose-btn { margin: 0 4px 12px; width: calc(100% - 8px); }

.folder-list { list-style: none; margin: 0; padding: 0; flex: 1; }
.folder-list li a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 9px 12px;
  font-size: 13px;
  color: var(--ink-2);
  border-radius: 8px;
}
.folder-list li a:hover { background: var(--accent-soft); color: var(--accent); }
.folder-list li a.active {
  background: var(--accent);
  color: #fff;
}
.folder-list .count { font-size: 11px; opacity: .75; }

.sidebar-user {
  border-top: 1px solid var(--line-soft);
  padding: 12px 8px 4px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.avatar {
  width: 30px;
  height: 30px;
  border-radius: 50%;
  background: var(--accent);
  color: #fff;
  display: grid;
  place-items: center;
  font-size: 12px;
  font-weight: 600;
}

.sidebar-user .name { font-size: 12px; font-weight: 600; }
.sidebar-user .email {
  font-size: 11px;
  color: var(--mute);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.mail-list-pane {
  border-right: 1px solid var(--line);
  display: flex;
  flex-direction: column;
  min-width: 0;
  background: rgba(255, 255, 255, 0.82);
  backdrop-filter: blur(10px);
}

.list-toolbar {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 10px;
  border-bottom: 1px solid var(--line-soft);
}

.search-box {
  flex: 1;
  display: flex;
  border: 1px solid var(--line);
  background: #fff;
  border-radius: var(--radius-sm);
}
.search-box input { border: none; min-height: 34px; border-radius: var(--radius-sm); }

.mail-list { overflow-y: auto; flex: 1; }

.mail-item {
  width: 100%;
  text-align: left;
  border: none;
  border-bottom: 1px solid var(--line-soft);
  background: transparent;
  padding: 12px;
  cursor: pointer;
  display: grid;
  gap: 3px;
}

.mail-item:hover { background: rgba(109, 74, 255, 0.05); }
.mail-item.active { background: var(--accent); color: #fff; }
.mail-item.active .preview,
.mail-item.active .when { color: rgba(255, 255, 255, 0.7); }
.mail-item.unread .from { font-weight: 700; }
.mail-item .row { display: flex; justify-content: space-between; gap: 8px; }
.mail-item .from { font-size: 13px; }
.mail-item .when { font-size: 11px; color: var(--mute); flex-shrink: 0; }
.mail-item .subject,
.mail-item .preview {
  font-size: 12px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.mail-item .preview { color: var(--mute); }

.mail-reader {
  display: flex;
  flex-direction: column;
  min-width: 0;
  background: rgba(255, 255, 255, 0.9);
}

.reader-toolbar {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 10px 16px;
  border-bottom: 1px solid var(--line-soft);
}

.icon-btn {
  width: 34px;
  height: 34px;
  border: 1px solid var(--line);
  background: #fff;
  display: grid;
  place-items: center;
  cursor: pointer;
  border-radius: 8px;
  color: var(--ink);
}
.icon-btn:hover { background: var(--accent-soft); border-color: rgba(109, 74, 255, 0.25); }
.icon-btn svg { width: 14px; height: 14px; stroke: currentColor; fill: none; stroke-width: 1.6; }

.reader-body {
  padding: 28px 32px 44px;
  overflow-y: auto;
  flex: 1;
}

.reader-empty {
  height: 100%;
  display: grid;
  place-items: center;
  color: var(--mute);
  text-align: center;
  padding: 40px;
}
.reader-empty img { height: 36px; margin: 0 auto 12px; opacity: .4; }

.reader-subject {
  font-family: var(--font-brand);
  font-weight: 700;
  font-size: 1.55rem;
  margin: 0 0 16px;
  letter-spacing: -0.03em;
}

.reader-meta {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  margin-bottom: 22px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--line-soft);
}
.reader-meta .who { flex: 1; min-width: 0; }
.reader-meta .who strong { display: block; font-size: 13px; }
.reader-meta .who span { font-size: 12px; color: var(--mute); }
.reader-meta .time { font-size: 12px; color: var(--mute); }

.reader-content {
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-2);
  max-width: 62ch;
}

.compose-overlay {
  position: fixed;
  inset: 0;
  background: rgba(20, 16, 40, 0.28);
  backdrop-filter: blur(4px);
  display: none;
  align-items: flex-end;
  justify-content: flex-end;
  padding: 18px;
  z-index: 100;
}
.compose-overlay.open { display: flex; }

.compose-window {
  width: min(560px, 100%);
  background: rgba(255, 255, 255, 0.88);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--glass-border);
  border-radius: 14px;
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
  max-height: min(640px, calc(100vh - 36px));
  overflow: hidden;
}

.compose-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 14px;
  background: linear-gradient(180deg, var(--accent-2), var(--accent));
  color: #fff;
}
.compose-header h3 { margin: 0; font-size: 14px; font-weight: 600; }

.compose-fields { border-bottom: 1px solid var(--line-soft); }
.compose-field {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 4px 14px;
  border-bottom: 1px solid var(--line-soft);
}
.compose-field:last-child { border-bottom: none; }
.compose-field label {
  font-size: 12px;
  color: var(--mute);
  width: 42px;
  flex-shrink: 0;
}
.compose-field input { border: none; min-height: 34px; padding: 4px 0; background: transparent; }

.compose-body { flex: 1; padding: 8px 14px; min-height: 200px; }
.compose-body textarea {
  width: 100%;
  height: 100%;
  min-height: 200px;
  border: none;
  resize: vertical;
  outline: none;
  background: transparent;
}

.compose-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 14px;
  border-top: 1px solid var(--line-soft);
}

.toast {
  position: fixed;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%) translateY(12px);
  background: rgba(31, 35, 40, 0.92);
  backdrop-filter: blur(10px);
  color: #fff;
  padding: 10px 14px;
  font-size: 13px;
  border-radius: 10px;
  opacity: 0;
  pointer-events: none;
  transition: opacity .2s, transform .2s var(--ease);
  z-index: 200;
}
.toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

.mobile-nav-toggle { display: none; }

@media (max-width: 980px) {
  .hero, .split, .auth-page { grid-template-columns: 1fr; }
  .nav-links { display: none; }
  .mail-app { grid-template-columns: 1fr; }
  .mail-sidebar { display: none; }
  .mail-sidebar.open {
    display: flex;
    position: fixed;
    inset: 0 auto 0 0;
    width: min(270px, 86vw);
    z-index: 80;
    box-shadow: var(--shadow);
  }
  .mail-list-pane.hide-mobile,
  .mail-reader.hide-mobile { display: none; }
  .mobile-nav-toggle { display: grid; place-items: center; }
  .auth-visual { min-height: 200px; }
}

@media (max-width: 640px) {
  .hero-cta { flex-direction: column; }
  .btn-lg { width: 100%; }
  .reader-body { padding: 18px 14px 32px; }
}