/* Reset */
* { margin: 0; padding: 0; box-sizing: border-box; }
body { background: #1a1a2e; font-family: 'Nunito Sans', sans-serif; min-height: 100vh; }

/* ── Phone frame (student app) ── */
.phone-frame {
  width: 390px;
  background: #000;
  border-radius: 50px;
  padding: 12px;
  box-shadow: 0 0 0 2px #333, 0 20px 60px rgba(0,0,0,0.5);
  position: relative;
  margin: 0 auto;
}
.phone-screen {
  width: 100%;
  border-radius: 40px;
  overflow: hidden;
  position: relative;
  background: #fff;
}
.phone-screen img.screen-bg {
  width: 100%;
  height: auto;
  display: block;
}

/* ── Browser frame (teacher dashboard) ── */
.browser-frame {
  width: 1200px;
  background: #2d2d2d;
  border-radius: 10px;
  overflow: hidden;
  margin: 0 auto;
  box-shadow: 0 20px 60px rgba(0,0,0,0.5);
}
.browser-chrome {
  background: #3c3c3c;
  padding: 10px 16px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.browser-dot { width: 12px; height: 12px; border-radius: 50%; }
.browser-dot.red { background: #ff5f57; }
.browser-dot.yellow { background: #ffbd2e; }
.browser-dot.green { background: #28c840; }
.browser-url {
  background: #fff;
  border-radius: 6px;
  padding: 4px 12px;
  font-size: 13px;
  color: #555;
  flex: 1;
  margin-left: 8px;
}
.browser-screen {
  position: relative;
  width: 100%;
}
.browser-screen img.screen-bg {
  width: 100%;
  display: block;
}

/* ── Clickable hotspots ── */
.hotspot {
  position: absolute;
  cursor: pointer;
  /* Debug: uncomment to visualize hotspots */
  /* background: rgba(255,100,100,0.3); border: 2px solid red; */
  border-radius: 8px;
  transition: background 0.15s;
}
.hotspot:hover { background: rgba(255,255,255,0.15); }

/* ── Navigation bar ── */
.nav {
  position: fixed;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  background: rgba(255,255,255,0.1);
  backdrop-filter: blur(10px);
  border-radius: 30px;
  padding: 10px 24px;
  display: flex;
  gap: 16px;
  z-index: 100;
}
.nav a {
  color: #fff;
  text-decoration: none;
  font-size: 14px;
  opacity: 0.7;
  transition: opacity 0.2s;
}
.nav a:hover, .nav a.active { opacity: 1; }

/* ── Screen wrapper ── */
.screen-wrapper {
  display: none;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  padding: 40px 20px 80px;
  gap: 20px;
}
.screen-wrapper.active { display: flex; }

.screen-label {
  color: rgba(255,255,255,0.5);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 2px;
  text-align: center;
}

/* ── Entry page ── */
.entry-page {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  gap: 32px;
  color: #fff;
  text-align: center;
  padding: 40px;
}
.entry-logo { font-size: 48px; font-weight: 800; letter-spacing: -2px; }
.entry-subtitle { opacity: 0.6; font-size: 16px; max-width: 400px; line-height: 1.5; }
.entry-cards {
  display: flex;
  gap: 24px;
  margin-top: 16px;
}
.entry-card {
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.12);
  border-radius: 16px;
  padding: 32px;
  cursor: pointer;
  transition: all 0.2s;
  min-width: 200px;
  text-decoration: none;
  color: #fff;
}
.entry-card:hover {
  background: rgba(255,255,255,0.14);
  transform: translateY(-2px);
}
.entry-card-icon { font-size: 36px; margin-bottom: 12px; }
.entry-card-title { font-size: 20px; font-weight: 700; }
.entry-card-desc { font-size: 13px; opacity: 0.6; margin-top: 6px; }

/* ── Quick nav buttons ── */
.quick-nav {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  justify-content: center;
  max-width: 500px;
}
.quick-nav button {
  background: rgba(255,255,255,0.1);
  border: none;
  color: #fff;
  padding: 6px 14px;
  border-radius: 20px;
  cursor: pointer;
  font-size: 13px;
  font-family: inherit;
  transition: background 0.15s;
}
.quick-nav button:hover { background: rgba(255,255,255,0.2); }
.quick-nav button.danger { background: rgba(255,100,100,0.2); }