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

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
  -webkit-tap-highlight-color: transparent;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  font-size: var(--fs-base);
  color: var(--text-primary);
  background: var(--bg-primary);
  line-height: 1.5;
  min-height: 100dvh;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent-text); text-decoration: none; }
button { font: inherit; cursor: pointer; border: none; background: none; color: inherit; }
input, select { font: inherit; color: inherit; }

.app {
  max-width: var(--max-width);
  margin: 0 auto;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  position: relative;
}

/* Header */
.header {
  height: var(--header-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--space-md);
  border-bottom: 1px solid var(--border);
  background: var(--bg-secondary);
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.header-title {
  font-size: var(--fs-lg);
  font-weight: 700;
  letter-spacing: -0.02em;
}

.header-actions { display: flex; gap: var(--space-sm); align-items: center; }
.header-btn {
  width: 36px; height: 36px;
  display: flex; align-items: center; justify-content: center;
  border-radius: var(--radius-sm);
  transition: background var(--duration) var(--ease);
  font-size: var(--fs-lg);
}
.header-btn:hover { background: var(--bg-card); }

/* Main content */
.main {
  flex: 1;
  padding: var(--space-md);
  padding-bottom: calc(var(--nav-height) + var(--space-lg));
  overflow-y: auto;
}

/* Bottom nav */
.nav {
  position: fixed;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 100%;
  max-width: var(--max-width);
  height: var(--nav-height);
  display: flex;
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  z-index: 100;
}

.nav-tab {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
  color: var(--text-muted);
  transition: color var(--duration) var(--ease);
  position: relative;
}

.nav-tab.active { color: var(--accent-text); }
.nav-tab.active::before {
  content: '';
  position: absolute;
  top: 0;
  left: 25%;
  right: 25%;
  height: 2px;
  background: var(--accent);
  border-radius: 0 0 2px 2px;
}

.nav-icon { font-size: 1.3rem; line-height: 1; }
.nav-label { font-size: var(--fs-xs); font-weight: 500; }

/* Tab panels */
.tab-panel { display: none; }
.tab-panel.active { display: block; }

/* Cards */
.card {
  background: var(--bg-card);
  border-radius: var(--radius-md);
  padding: var(--space-md);
  box-shadow: var(--shadow-card);
  margin-bottom: var(--space-md);
}

.card-title {
  font-size: var(--fs-sm);
  font-weight: 600;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: var(--space-sm);
}

/* Utility */
.empty-state {
  text-align: center;
  color: var(--text-muted);
  padding: var(--space-xl);
  font-size: var(--fs-sm);
}

.sr-only {
  position: absolute; width: 1px; height: 1px;
  padding: 0; margin: -1px; overflow: hidden;
  clip: rect(0,0,0,0); border: 0;
}

/* Scrollbar */
::-webkit-scrollbar { width: 4px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: 4px; }