:root {
  --gmail-bg: #f6f8fc;
  --gmail-white: #ffffff;
  --gmail-text-primary: #202124;
  --gmail-text-secondary: #5f6368;
  --gmail-text-light: #80868b;
  --gmail-border: #e0e0e0;
  --gmail-hover: #f2f2f2;
  --gmail-blue: #1a73e8;
  --gmail-blue-hover: #1765cc;
  --gmail-red: #d93025;
  --gmail-yellow: #f9ab00;
  --gmail-green: #1e8e3e;
  --gmail-sidebar-width: 256px;
  --gmail-header-height: 64px;
  --gmail-font-ui: 'Google Sans', 'Roboto', sans-serif;
  --gmail-font-body: 'Roboto', sans-serif;
}

#app {
  height: 100vh;
  display: flex;
  flex-direction: column;
}

.screen {
  height: 100%;
  width: 100%;
}

#screen-inbox {
  display: flex;
  flex-direction: column;
  height: 100%;
  min-height: 0;
}

/* Gmail Header */
.gmail-header {
  display: flex;
  align-items: center;
  height: var(--gmail-header-height);
  padding: 0 8px;
  background: var(--gmail-white);
  border-bottom: none;
}

.gmail-header-left {
  display: flex;
  align-items: center;
  width: var(--gmail-sidebar-width);
  padding-left: 8px;
}

.gmail-menu-btn {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--gmail-text-secondary);
}

.gmail-menu-btn:hover {
  background: var(--gmail-hover);
}

.gmail-logo {
  display: flex;
  align-items: center;
  gap: 4px;
  margin-left: 4px;
}

.gmail-logo-text {
  font-family: 'Google Sans', sans-serif;
  font-size: 22px;
  color: var(--gmail-text-secondary);
  font-weight: 400;
}

.gmail-search {
  flex: 1;
  max-width: 720px;
  margin: 0 auto;
  background: #eaf1fb;
  border-radius: 24px;
  height: 48px;
  display: flex;
  align-items: center;
  padding: 0 16px;
  gap: 12px;
}

.gmail-search .material-icons {
  color: var(--gmail-text-secondary);
}

.gmail-search input {
  border: none;
  background: none;
  outline: none;
  flex: 1;
  font-size: 16px;
  font-family: var(--gmail-font-body);
  color: var(--gmail-text-primary);
}

.gmail-search input::placeholder {
  color: var(--gmail-text-secondary);
}

.gmail-header-right {
  display: flex;
  align-items: center;
  gap: 8px;
  padding-right: 16px;
}

.gmail-difficulty-badge {
  font-size: 11px;
  font-weight: 500;
  color: var(--gmail-text-light);
  background: #f1f3f4;
  padding: 3px 10px;
  border-radius: 12px;
  white-space: nowrap;
}

.gmail-difficulty-badge:empty {
  display: none;
}

.gmail-restart-btn {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--gmail-text-light);
  transition: all 0.15s;
}

.gmail-restart-btn:hover {
  background: var(--gmail-hover);
  color: var(--gmail-text-secondary);
}

.gmail-avatar {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--gmail-blue);
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 13px;
  font-weight: 500;
}

/* Gmail Body */
.gmail-body {
  display: flex;
  flex: 1;
  overflow: hidden;
  min-height: 0;
}

/* Gmail Sidebar */
.gmail-sidebar {
  width: var(--gmail-sidebar-width);
  padding: 8px 12px 0 12px;
  overflow-y: auto;
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  height: 100%;
}

.gmail-compose-btn {
  display: flex;
  align-items: center;
  gap: 12px;
  height: 56px;
  padding: 0 24px;
  background: #c2e7ff;
  border-radius: 16px;
  font-family: var(--gmail-font-ui);
  font-size: 14px;
  font-weight: 500;
  color: var(--gmail-text-primary);
  margin-bottom: 12px;
  width: fit-content;
  box-shadow: none;
  transition: box-shadow 0.2s;
}

.gmail-compose-btn:hover {
  box-shadow: 0 1px 3px rgba(0,0,0,0.2);
}

.gmail-nav {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.gmail-nav-item {
  display: flex;
  align-items: center;
  gap: 16px;
  height: 32px;
  padding: 0 12px 0 12px;
  border-radius: 0 16px 16px 0;
  font-size: 14px;
  color: var(--gmail-text-secondary);
  cursor: pointer;
  font-weight: 500;
  position: relative;
}

.gmail-nav-item:hover {
  background: var(--gmail-hover);
}

.gmail-nav-item.active {
  background: #d3e3fd;
  color: var(--gmail-text-primary);
  font-weight: 700;
}

.gmail-nav-item .material-icons {
  font-size: 20px;
}

.gmail-nav-label {
  flex: 1;
}

.gmail-nav-count {
  font-size: 12px;
  font-weight: 700;
}

.gmail-sidebar-footer {
  margin-top: auto;
  padding: 16px 12px;
  font-size: 11px;
  color: #bdc1c6;
}

/* Gmail Main Content Area */
.gmail-main {
  flex: 1;
  background: var(--gmail-white);
  border-radius: 16px;
  margin-right: 16px;
  margin-bottom: 16px;
  overflow-y: auto;
  min-width: 0;
}