/* --- Global & Reset --- */
:root {
  /* Cosmic Colors */
  --primary-bg: #0a0e17; /* Deep space */
  --secondary-bg: #121826; /* Slightly lighter space */
  --card-bg: rgba(18, 24, 38, 0.85); /* Message card bg */
  --accent-glow: #00f0ff; /* Neon blue */
  --accent-accent: #b027ff; /* Neon purple */
  --text-primary: #e0e0ff; /* Light text */
  --text-secondary: #a0a0c0; /* Muted text */
  --success: #00ff9d; /* Success/good state */

  /* Fonts */
  --font-main: 'Orbitron', monospace;
  --font-ui: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;

  /* Responsive Base Sizes */
  --base-font-size: clamp(0.8rem, 2vw, 1rem);
  --base-padding: clamp(8px, 3vw, 20px);
  --base-margin: clamp(4px, 2vw, 10px);
  --border-radius: clamp(8px, 2vw, 12px);
  --avatar-size-lg: clamp(32px, 5vw, 36px);
  --avatar-size-sm: clamp(28px, 4vw, 32px);
  --max-message-width: 90%;
}

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

body {
  font-family: var(--font-ui);
  background: var(--primary-bg);
  color: var(--text-primary);
  min-height: 100vh;
  overflow: hidden; /* Prevent default scroll */
  position: relative;
  font-size: var(--base-font-size); /* Apply responsive base font size */
}

body::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: radial-gradient(circle at 10% 20%, rgba(176, 39, 255, 0.1) 0%, transparent 20%),              radial-gradient(circle at 90% 80%, rgba(0, 240, 255, 0.1) 0%, transparent 20%);
  z-index: -1;
  pointer-events: none;
}


/* --- Screens --- */
.screen {
  display: none;
  height: 100vh;
  width: 100%;
  padding: var(--base-padding);
  flex-direction: column;
  justify-content: center;
  align-items: center;
}

.screen.active {
  display: flex;
  animation: fadeInScale 0.4s ease-out forwards;
}

@keyframes fadeInScale {
  from { opacity: 0; transform: scale(0.95); }
  to { opacity: 1; transform: scale(1); }
}


/* --- Join Screen --- */
.welcome-container {
  text-align: center;
  max-width: min(400px, 95vw); /* Max 400px, or 95% of viewport width if smaller */
  width: 100%;
}

.logo {
  font-family: var(--font-main);
  font-size: clamp(2rem, 5vw, 2.8rem); /* Responsive size */
  margin-bottom: calc(var(--base-margin) * 0.5);
  background: linear-gradient(45deg, var(--accent-glow), var(--accent-accent));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  text-shadow: 0 0 10px rgba(0, 240, 255, 0.3);
  display: inline-block;
}

.welcome-container p {
  color: var(--text-secondary);
  margin-bottom: calc(var(--base-margin) * 2);  font-size: clamp(0.9rem, 3vw, 1.1rem); /* Responsive size */
}

.input-group {
  display: flex;
  flex-direction: column;
  gap: var(--base-margin);
  width: 100%;
}

.input-group input {
  padding: calc(var(--base-padding) * 0.7) var(--base-padding);
  background: var(--card-bg);
  border: 1px solid rgba(0, 240, 255, 0.3);
  border-radius: var(--border-radius);
  color: var(--text-primary);
  font-size: var(--base-font-size);
  outline: none;
  transition: border-color 0.3s, box-shadow 0.3s;
}

.input-group input:focus {
  border-color: var(--accent-glow);
  box-shadow: 0 0 15px rgba(0, 240, 255, 0.4);
}

.input-group button {
  padding: calc(var(--base-padding) * 0.7) calc(var(--base-padding) * 1.1);
  background: linear-gradient(45deg, var(--accent-glow), var(--accent-accent));
  border: none;
  border-radius: var(--border-radius);
  color: #0a0e17;
  font-weight: bold;
  font-size: var(--base-font-size);
  cursor: pointer;
  transition: transform 0.2s, filter brightness(0.9);
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 0.5rem;
}

.input-group button:hover {
  transform: translateY(-2px);
  filter: brightness(1.1);
}

/* --- Chat Screen Layout --- */
#chat-screen {
  flex-direction: column;}

/* --- Chat Header --- */
.chat-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: calc(var(--base-padding) * 0.6) var(--base-padding);
  background: var(--card-bg);
  border-bottom: 1px solid rgba(0, 240, 255, 0.2);
  backdrop-filter: blur(10px);
  border-radius: var(--border-radius) var(--border-radius) 0 0;
}

.room-info, .user-status {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-main);
  font-size: clamp(0.9rem, 3vw, 1.1rem); /* Responsive size */
}

.room-info span {
  color: var(--accent-glow);
}

.user-status i {
  font-size: 0.8em; /* Relative to parent font size */
}


/* --- Messages Container --- */
#messages {
  flex: 1;
  overflow-y: auto;
  padding: var(--base-padding);
  display: flex;
  flex-direction: column;
  gap: var(--base-margin); /* Space between messages */
  background: var(--secondary-bg);
  border-left: 1px solid rgba(0, 240, 255, 0.1);
  border-right: 1px solid rgba(0, 240, 255, 0.1);
  /* Scrollbar styling */
  scrollbar-width: thin;
  scrollbar-color: var(--accent-glow) var(--secondary-bg);
}

#messages::-webkit-scrollbar {
  width: clamp(6px, 2vw, 8px); /* Responsive scrollbar width */
}
#messages::-webkit-scrollbar-track {
  background: var(--secondary-bg);
}

#messages::-webkit-scrollbar-thumb {
  background-color: var(--accent-glow);
  border-radius: calc(var(--border-radius) * 0.5);
}


/* --- Individual Message --- */
.message {
  display: flex;
  gap: var(--base-margin);
  align-items: flex-start;
  padding: calc(var(--base-padding) * 0.7) var(--base-padding);
  background: var(--card-bg);
  border-radius: calc(var(--border-radius) * 1.33); /* Slightly larger radius */
  border: 1px solid rgba(0, 240, 255, 0.15);
  max-width: var(--max-message-width); /* Responsive max width */
  animation: messageAppear 0.3s ease-out forwards;
  opacity: 0;
  transform: translateY(10px);
}

@keyframes messageAppear {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.avatar {
  width: var(--avatar-size-lg); /* Responsive size */
  height: var(--avatar-size-lg); /* Responsive size */
  border-radius: 50%;
  background: linear-gradient(45deg, var(--accent-glow), var(--accent-accent));
  display: flex;
  justify-content: center;
  align-items: center;
  flex-shrink: 0;
  font-weight: bold;
  font-size: calc(var(--base-font-size) * 0.9); /* Responsive font size */
  color: var(--primary-bg);
  font-family: var(--font-main);
  /* Optional glow */
  box-shadow: 0 0 8px rgba(0, 240, 255, 0.3);
}
.message-content {
  flex: 1;
}

.username {
  font-weight: bold;
  color: var(--accent-glow);
  margin-bottom: calc(var(--base-margin) * 0.4);
  font-size: calc(var(--base-font-size) * 0.95); /* Responsive font size */
  font-family: var(--font-main);
}

.text {
  color: var(--text-primary);
  line-height: 1.5;
  font-size: var(--base-font-size); /* Consistent with body */
}


/* --- Input Area (Footer) --- */
.input-area {
  padding: var(--base-padding);
  background: var(--card-bg);
  border-top: 1px solid rgba(0, 240, 255, 0.2);
  backdrop-filter: blur(10px);
  border-radius: 0 0 var(--border-radius) var(--border-radius);
}

.input-box {
  display: flex;
  gap: calc(var(--base-margin) * 0.5);
}

.input-box input {
  flex: 1;
  padding: calc(var(--base-padding) * 0.7) var(--base-padding);
  background: var(--secondary-bg);
  border: 1px solid rgba(0, 240, 255, 0.2);
  border-radius: var(--border-radius);
  color: var(--text-primary);
  font-size: var(--base-font-size);
  outline: none;
  transition: border-color 0.3s;
}

.input-box input:focus {
  border-color: var(--accent-glow);
}

.input-box button {  padding: calc(var(--base-padding) * 0.7) calc(var(--base-padding) * 1.1);
  background: var(--accent-glow);
  color: var(--primary-bg);
  border: none;
  border-radius: var(--border-radius);
  cursor: pointer;
  font-size: calc(var(--base-font-size) * 1.1); /* Responsive icon size */
  display: flex;
  justify-content: center;
  align-items: center;
  transition: background 0.3s, transform 0.2s;
  min-width: fit-content; /* Ensure button doesn't shrink too much */
}

.input-box button:hover {
  background: #00ccdd; /* Slightly darker on hover */
  transform: scale(1.03);
}

/* --- Responsive Adjustments --- */
@media (max-width: 768px) {
    /* Adjust max message width for smaller screens */
    :root {
        --max-message-width: 95%;
    }
    /* Adjust avatar size */
    .avatar {
        width: var(--avatar-size-sm);
        height: var(--avatar-size-sm);
        font-size: calc(var(--base-font-size) * 0.8);
    }
    /* Adjust header font size slightly */
    .room-info, .user-status {
        font-size: clamp(0.85rem, 2.8vw, 1rem);
    }
    /* Adjust message font sizes */
    .username {
        font-size: calc(var(--base-font-size) * 0.9);
    }
    .text {
        font-size: var(--base-font-size);
    }
    /* Adjust input area padding */
    .input-area {
        padding: calc(var(--base-padding) * 0.8);
    }
    /* Ensure input box items don't wrap unexpectedly */
    .input-box {
        flex-wrap: nowrap; /* Keep inputs and button on same line */
    }    .input-box input {
        min-width: 0; /* Allow input to shrink */
    }
}

@media (max-width: 480px) {
    /* Further adjust max message width */
    :root {
        --max-message-width: 100%;
        --border-radius: 10px; /* Slightly smaller radius on very small screens */
    }
    /* Adjust logo size */
    .logo {
        font-size: clamp(1.8rem, 6vw, 2.2rem);
    }
    /* Adjust welcome text */
    .welcome-container p {
        font-size: clamp(0.8rem, 2.8vw, 1rem);
        margin-bottom: calc(var(--base-margin) * 1.5);
    }
    /* Adjust button text size */
    .input-group button {
        font-size: calc(var(--base-font-size) * 0.95);
        padding: calc(var(--base-padding) * 0.6) calc(var(--base-padding) * 0.9);
    }
    /* Adjust message padding */
    .message {
        padding: calc(var(--base-padding) * 0.6) calc(var(--base-padding) * 0.8);
        gap: calc(var(--base-margin) * 0.8);
    }
    /* Adjust input box padding */
    .input-box input {
        padding: calc(var(--base-padding) * 0.6) calc(var(--base-padding) * 0.8);
    }
    .input-box button {
        padding: calc(var(--base-padding) * 0.6) calc(var(--base-padding) * 0.9);
        font-size: calc(var(--base-font-size) * 1.0);
    }
}

/* --- Landscape Orientation Adjustment --- */
@media (orientation: landscape) and (max-height: 500px) {
    /* Adjust for short landscape screens */
    .screen {
        justify-content: flex-start;
        padding-top: 10vh; /* Add some top padding */
    }
    #messages {
        height: 60vh; /* Reduce messages area height */
    }}