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

:root {
  --bg-primary: #1a1a2e;
  --bg-secondary: #16213e;
  --bg-panel: #0f0f1a;
  --accent: #e94560;
  --accent-hover: #ff6b81;
  --text-primary: #eaeaea;
  --text-secondary: #a0a0b0;
  --border: #2a2a4a;
  --success: #4ecca3;
  --warning: #f0a500;
  --radius: 8px;
  --shadow: 0 4px 24px rgba(0, 0, 0, 0.4);
}

html, body {
  height: 100%;
  font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.5;
}

/* ── Index page ── */

.landing {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 2rem;
  gap: 2rem;
}

.landing__header {
  text-align: center;
}

.landing__title {
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}

.landing__subtitle {
  color: var(--text-secondary);
  font-size: 1.1rem;
  max-width: 520px;
}

.dropzone {
  width: 100%;
  max-width: 560px;
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  padding: 3rem 2rem;
  text-align: center;
  cursor: pointer;
  transition: border-color 0.2s, background 0.2s;
  background: var(--bg-secondary);
}

.dropzone:hover,
.dropzone--active {
  border-color: var(--accent);
  background: rgba(233, 69, 96, 0.05);
}

.dropzone__icon {
  font-size: 3rem;
  margin-bottom: 1rem;
  opacity: 0.6;
}

.dropzone__text {
  color: var(--text-secondary);
  margin-bottom: 1rem;
}

.dropzone__filename {
  color: var(--success);
  font-weight: 600;
  margin-top: 0.75rem;
  word-break: break-all;
}

.instructions {
  max-width: 560px;
  color: var(--text-secondary);
  font-size: 0.9rem;
}

.instructions ol {
  padding-left: 1.25rem;
}

.instructions li {
  margin-bottom: 0.4rem;
}

.browser-warning {
  max-width: 560px;
  padding: 0.75rem 1rem;
  background: rgba(240, 165, 0, 0.15);
  border: 1px solid var(--warning);
  border-radius: var(--radius);
  color: var(--warning);
  font-size: 0.85rem;
  display: none;
}

.browser-warning--visible {
  display: block;
}

/* ── Buttons ── */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.65rem 1.4rem;
  border: none;
  border-radius: var(--radius);
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.2s, opacity 0.2s;
}

.btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.btn--primary {
  background: var(--accent);
  color: #fff;
}

.btn--primary:not(:disabled):hover {
  background: var(--accent-hover);
}

.btn--secondary {
  background: var(--bg-secondary);
  color: var(--text-primary);
  border: 1px solid var(--border);
}

.btn--secondary:not(:disabled):hover {
  background: var(--border);
}

.btn--danger {
  background: transparent;
  color: var(--accent);
  border: 1px solid var(--accent);
}

.btn--danger:not(:disabled):hover {
  background: rgba(233, 69, 96, 0.15);
}

.btn--icon {
  padding: 0.5rem 0.75rem;
  font-size: 1.1rem;
  min-width: 2.5rem;
  justify-content: center;
}

/* ── Presenter page ── */

.presenter {
  height: 100vh;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.presenter__main {
  flex: 1;
  display: grid;
  grid-template-columns: 1fr 280px;
  gap: 1rem;
  padding: 1rem;
  min-height: 0;
  overflow: hidden;
}

.presenter__current {
  display: flex;
  flex-direction: column;
  min-height: 0;
  overflow: hidden;
}

.presenter__current-label,
.presenter__next-label {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
}

.slide-frame {
  flex: 1;
  width: 100%;
  min-height: 0;
  background: var(--bg-panel);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  box-shadow: var(--shadow);
}

.slide-frame canvas {
  display: block;
  max-width: 100%;
  max-height: 100%;
}

.presenter__sidebar {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  min-height: 0;
  overflow: hidden;
}

.presenter__next {
  display: flex;
  flex-direction: column;
  flex: 1;
  min-height: 0;
}

.presenter__next .slide-frame {
  flex: 1;
}

.presenter__next-end {
  flex: 1;
  background: var(--bg-panel);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  font-size: 0.9rem;
  text-align: center;
  padding: 1rem;
}

.presenter__timer-panel {
  background: var(--bg-secondary);
  border-radius: var(--radius);
  padding: 1rem;
  text-align: center;
}

.timer-display {
  font-size: 2rem;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.05em;
  margin-bottom: 0.75rem;
}

.timer-controls {
  display: flex;
  gap: 0.5rem;
  justify-content: center;
  margin-bottom: 0.75rem;
}

.slide-counter {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.slide-counter strong {
  color: var(--text-primary);
}

.presenter__toolbar {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem 1rem;
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  flex-shrink: 0;
}

.presenter__toolbar-spacer {
  flex: 1;
}

.presenter__status {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.presenter__status--warning {
  color: var(--warning);
}

.presenter__loading {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.7);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  z-index: 100;
}

.presenter__loading.hidden {
  display: none;
}

.spinner {
  width: 48px;
  height: 48px;
  border: 4px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* ── Audience page ── */

.audience {
  height: 100vh;
  background: #000;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  position: relative;
}

.audience__slide {
  width: 100vw;
  height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
}

.audience__slide canvas {
  display: block;
  max-width: 100vw;
  max-height: 100vh;
}

.audience__overlay {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.85);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  cursor: pointer;
  z-index: 10;
}

.audience__overlay.hidden {
  display: none;
}

.audience__overlay-text {
  font-size: 1.5rem;
  color: var(--text-primary);
  text-align: center;
  padding: 0 2rem;
}

.audience__overlay-hint {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.audience__loading {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: #000;
}

.audience__loading.hidden {
  display: none;
}

.hidden {
  display: none !important;
}