@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&display=swap');

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: linear-gradient(135deg, #1e293b 0%, #0f172a 100%);
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1rem;
  color: #fff;
}

.phone-app {
  width: 100%;
  max-width: 400px;
  height: 700px;
  background: #000;
  border-radius: 40px;
  position: relative;
  overflow: hidden;
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
  display: flex;
  flex-direction: column;
}

/* Screen Management */
.screen {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 2rem;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.4s ease;
  z-index: 1;
}

.screen.active {
  opacity: 1;
  pointer-events: all;
  z-index: 10;
}

/* START SCREEN */
.logo-area {
  margin-bottom: 3rem;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.logo-circle {
  width: 100px;
  height: 100px;
  background: #2563eb;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.5rem;
  box-shadow: 0 0 30px rgba(37, 99, 235, 0.3);
}

.app-title {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  text-align: center;
}

.app-subtitle {
  color: #94a3b8;
  font-size: 0.875rem;
  text-align: center;
}

.btn-large {
  width: 100%;
  padding: 1.25rem;
  border-radius: 99px;
  border: none;
  font-weight: 600;
  font-size: 1.125rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
  transition: transform 0.2s, filter 0.2s;
}

.btn-large:active {
  transform: scale(0.98);
}

.btn-start {
  background: #10b981;
  color: #fff;
  box-shadow: 0 10px 30px rgba(16, 185, 129, 0.3);
}

.btn-start:hover {
  background: #059669;
}

/* CALL SCREEN */
.contact-info {
  margin-top: 2rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  margin-bottom: auto;
}

.avatar-large {
  width: 120px;
  height: 120px;
  background: #2563eb;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.5rem;
  font-size: 3rem;
}

.contact-name {
  font-size: 1.75rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.call-status {
  color: #10b981;
  font-weight: 500;
  font-size: 0.875rem;
  margin-bottom: 0.5rem;
}

.call-timer {
  font-family: monospace;
  color: #94a3b8;
  font-size: 1rem;
}

/* WAVEFORM */
.waveform {
  display: flex;
  align-items: center;
  gap: 6px;
  height: 60px;
  margin-bottom: 4rem;
}

.bar {
  width: 6px;
  background: #3b82f6;
  border-radius: 99px;
  height: 10%;
  animation: none;
}

.waveform.active .bar {
  animation: wave 1s ease-in-out infinite;
}

@keyframes wave {
  0%, 100% { height: 10%; }
  50% { height: 100%; }
}

.waveform.active .bar:nth-child(1) { animation-delay: 0.0s; }
.waveform.active .bar:nth-child(2) { animation-delay: 0.1s; }
.waveform.active .bar:nth-child(3) { animation-delay: 0.2s; }
.waveform.active .bar:nth-child(4) { animation-delay: 0.3s; }
.waveform.active .bar:nth-child(5) { animation-delay: 0.4s; }

/* CONTROLS */
.controls {
  margin-bottom: 3rem;
  display: flex;
  gap: 2rem;
}

.btn-control {
  width: 64px;
  height: 64px;
  border-radius: 50%;
  border: none;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  background: rgba(255, 255, 255, 0.1);
  color: #fff;
  transition: background 0.2s;
}

.btn-control:hover {
  background: rgba(255, 255, 255, 0.2);
}

.btn-end {
  background: #ef4444;
  width: 72px;
  height: 72px;
  box-shadow: 0 10px 30px rgba(239, 68, 68, 0.3);
}

.btn-end:hover {
  background: #dc2626;
}

/* END SCREEN */
.end-message {
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: 2rem;
}