/* === Reset & Base === */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --bg: #0f0f13;
  --surface: #1a1a23;
  --surface-hover: #24243a;
  --border: #2a2a3e;
  --text: #e8e8f0;
  --text-muted: #8888a0;
  --accent: #4ade80;
  --accent-dim: #22c55e;
  --danger: #ef4444;
  --danger-dim: #dc2626;
  --radius: 10px;
  --radius-sm: 6px;
}

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
  min-height: 100svh;
  display: flex;
  justify-content: center;
}

#app {
  width: 100%;
  max-width: 480px;
  padding: 16px;
}

/* === Header === */
.header {
  text-align: center;
  padding: 32px 0 24px;
}

.header__title {
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.header__sub {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-top: 4px;
}

/* === States === */
.state {
  text-align: center;
  padding: 40px 16px;
}

.state__text {
  color: var(--text-muted);
  font-size: 0.9375rem;
}

.state__text--error {
  color: var(--danger);
  margin-bottom: 16px;
}

.hidden {
  display: none !important;
}

/* === Buttons === */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  border: none;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s, transform 0.1s;
  min-height: 40px;
  min-width: 40px;
}

.btn:active {
  transform: scale(0.96);
}

.btn--icon {
  background: var(--surface);
  color: var(--text-muted);
  border: 1px solid var(--border);
  padding: 8px;
}

.btn--icon:hover {
  background: var(--surface-hover);
  color: var(--text);
}

.btn--icon.copied {
  color: var(--accent);
  border-color: var(--accent-dim);
}

.btn--secondary {
  background: var(--surface);
  color: var(--text);
  border: 1px solid var(--border);
  padding: 8px 20px;
}

.btn--secondary:hover {
  background: var(--surface-hover);
}

.btn--danger {
  background: transparent;
  color: var(--danger);
  border: 1px solid var(--danger-dim);
  padding: 6px 16px;
  font-size: 0.8125rem;
  min-height: 32px;
}

.btn--danger:hover {
  background: rgba(239, 68, 68, 0.1);
}

/* === Address Card === */
.address-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
  margin-bottom: 20px;
}

.address-card__label {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  margin-bottom: 8px;
}

.address-card__row {
  display: flex;
  align-items: center;
  gap: 10px;
}

.address-card__code {
  flex: 1;
  font-family: 'SF Mono', 'Fira Code', 'JetBrains Mono', monospace;
  font-size: 1rem;
  font-weight: 600;
  color: var(--text);
  background: var(--bg);
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  word-break: break-all;
  user-select: all;
}

/* === Messages === */
.messages-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
}

.messages-header__title {
  font-size: 0.9375rem;
  font-weight: 600;
}

.messages-header__actions {
  display: flex;
  align-items: center;
  gap: 10px;
}

.messages-header__count {
  font-size: 0.8125rem;
  color: var(--text-muted);
  font-variant-numeric: tabular-nums;
}

.messages {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

/* === Message Card === */
.message-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 16px;
  transition: border-color 0.2s;
}

.message-card--new {
  border-color: var(--accent-dim);
  animation: fadeIn 0.3s ease-out;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

.message-card__header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 8px;
  margin-bottom: 6px;
}

.message-card__from {
  font-size: 0.8125rem;
  color: var(--text-muted);
  word-break: break-all;
}

.message-card__time {
  font-size: 0.75rem;
  color: var(--text-muted);
  white-space: nowrap;
  flex-shrink: 0;
}

.message-card__subject {
  font-size: 0.875rem;
  font-weight: 500;
  margin-bottom: 10px;
  color: var(--text);
}

/* === OTP Display === */
.message-card__otp {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 4px;
}

.message-card__otp-code {
  font-family: 'SF Mono', 'Fira Code', 'JetBrains Mono', monospace;
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--accent);
  letter-spacing: 0.06em;
  line-height: 1.2;
  user-select: all;
}

.message-card__otp-actions {
  display: flex;
  gap: 6px;
  margin-left: auto;
  flex-shrink: 0;
}

.btn--copy-otp {
  background: var(--accent-dim);
  color: #000;
  padding: 8px 16px;
  font-size: 0.8125rem;
  font-weight: 700;
  border-radius: var(--radius-sm);
  border: none;
  min-height: 36px;
  cursor: pointer;
  transition: background 0.15s, transform 0.1s;
}

.btn--copy-otp:hover {
  background: var(--accent);
}

.btn--copy-otp:active {
  transform: scale(0.96);
}

.btn--copy-otp.copied {
  background: var(--accent);
}

.btn--delete-msg {
  background: transparent;
  color: var(--text-muted);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 6px 10px;
  font-size: 0.75rem;
  cursor: pointer;
  transition: color 0.15s, border-color 0.15s;
  min-height: 36px;
}

.btn--delete-msg:hover {
  color: var(--danger);
  border-color: var(--danger-dim);
}

.message-card__no-otp {
  font-size: 0.8125rem;
  color: var(--text-muted);
  font-style: italic;
}

/* === Responsive === */
@media (max-width: 400px) {
  #app { padding: 12px; }
  .header { padding: 20px 0 16px; }
  .message-card__otp-code { font-size: 1.25rem; }
}