/* ========== CSS Variables ========== */
:root {
  --bg-start: #0a0e27;
  --bg-end: #1a0a2e;
  --card-bg: rgba(15, 15, 35, 0.85);
  --card-border: rgba(255, 255, 255, 0.08);
  --accent: #a78bfa;
  --accent-dim: rgba(167, 139, 250, 0.3);
  --user-bubble-start: #667eea;
  --user-bubble-end: #764ba2;
  --bot-bubble: rgba(255, 255, 255, 0.06);
  --text-primary: rgba(255, 255, 255, 0.9);
  --text-secondary: rgba(255, 255, 255, 0.55);
  --text-dim: rgba(255, 255, 255, 0.35);
  --online-green: #34d399;
  --glow-purple: #c084fc;
  --glow-pink: #f9a8d4;
  --danger: #f87171;
  --radius-lg: 24px;
  --radius-md: 16px;
  --radius-sm: 12px;
  --radius-xs: 8px;
}

/* ========== Reset & Base ========== */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
}

html, body {
  height: 100vh;
  height: 100dvh;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  font-size: 15px;
  line-height: 1.6;
  color: var(--text-primary);
  background: linear-gradient(135deg, var(--bg-start), var(--bg-end));
  overflow: hidden;
  overscroll-behavior: none;
  -webkit-font-smoothing: antialiased;
}

/* ========== Card Container ========== */
.card {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  width: 100%;
  height: 100vh;
  height: 100dvh;
  max-height: 100vh;
  max-height: 100dvh;
  background: var(--card-bg);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
}

/* ========== Card Header ========== */
.card-header {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: calc(18px + env(safe-area-inset-top, 0px)) max(20px, env(safe-area-inset-right, 0px)) 18px max(20px, env(safe-area-inset-left, 0px));
  border-bottom: 1px solid var(--card-border);
  flex-shrink: 0;
}

.avatar-wrapper {
  position: relative;
  flex-shrink: 0;
}

.avatar {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  object-fit: cover;
  position: relative;
  z-index: 1;
  background: var(--bot-bubble);
}

.header-info {
  flex: 1;
  min-width: 0;
}

.char-name {
  font-size: 17px;
  font-weight: 600;
  color: var(--text-primary);
  letter-spacing: 0.5px;
}

.char-title {
  font-size: 12px;
  color: var(--text-secondary);
  margin-top: 2px;
}

.status {
  display: flex;
  align-items: center;
  gap: 5px;
  margin-top: 4px;
}

.status-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--online-green);
  box-shadow: 0 0 6px var(--online-green);
}

.status-text {
  font-size: 11px;
  color: var(--text-dim);
}

.header-actions {
  display: flex;
  gap: 4px;
  flex-shrink: 0;
}

.icon-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border: none;
  border-radius: 50%;
  background: transparent;
  color: var(--text-dim);
  cursor: pointer;
  transition: all 0.2s ease;
  user-select: none;
}

/* ========== Chat Area ========== */
.chat-area {
  flex: 1;
  overflow-y: auto;
  overflow-x: hidden;
  padding: 16px max(20px, env(safe-area-inset-right, 0px)) 16px max(20px, env(safe-area-inset-left, 0px));
  scroll-behavior: smooth;
  -webkit-overflow-scrolling: touch;
}

.chat-area::-webkit-scrollbar {
  width: 4px;
}

.chat-area::-webkit-scrollbar-track {
  background: transparent;
}

.chat-area::-webkit-scrollbar-thumb {
  background: rgba(255, 255, 255, 0.1);
  border-radius: 4px;
}

/* ========== Input Area ========== */
.input-area {
  padding: 14px max(20px, env(safe-area-inset-right, 0px)) calc(20px + env(safe-area-inset-bottom, 0px)) max(20px, env(safe-area-inset-left, 0px));
  border-top: 1px solid var(--card-border);
  flex-shrink: 0;
}

.input-wrapper {
  display: flex;
  align-items: flex-end;
  gap: 10px;
  background: rgba(255, 255, 255, 0.05);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-md);
  padding: 8px 8px 8px 16px;
  transition: border-color 0.2s ease;
}

.input-wrapper:focus-within {
  border-color: var(--accent-dim);
}

#userInput {
  flex: 1;
  background: none;
  border: none;
  outline: none;
  color: var(--text-primary);
  font-size: 16px;
  font-family: inherit;
  line-height: 1.5;
  resize: none;
  max-height: 96px;
  padding: 4px 0;
}

#userInput::placeholder {
  color: var(--text-dim);
}

.send-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border: none;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--user-bubble-start), var(--user-bubble-end));
  color: #fff;
  cursor: pointer;
  flex-shrink: 0;
  transition: all 0.2s ease;
  opacity: 0.7;
  user-select: none;
}

.send-btn:active {
  opacity: 1;
  transform: scale(0.95);
}

.send-btn:disabled {
  opacity: 0.3;
  cursor: not-allowed;
  transform: none;
}

/* ========== Modal ========== */
.modal-overlay {
  position: fixed;
  inset: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(8px);
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s ease;
}

.modal-overlay.active {
  opacity: 1;
  visibility: visible;
}

.modal {
  width: 90%;
  max-width: 380px;
  background: #1a1a2e;
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  padding: 28px 24px;
  transform: translateY(20px) scale(0.95);
  transition: transform 0.3s ease;
}

.modal-overlay.active .modal {
  transform: translateY(0) scale(1);
}

.modal-header h2 {
  font-size: 18px;
  font-weight: 600;
  color: var(--text-primary);
}

.modal-header p {
  font-size: 13px;
  color: var(--text-secondary);
  margin-top: 6px;
}

.modal-body {
  margin-top: 20px;
}

.modal-body input {
  width: 100%;
  padding: 14px 16px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-xs);
  color: var(--text-primary);
  font-size: 16px;
  font-family: monospace;
  outline: none;
  transition: border-color 0.2s ease;
}

.modal-body input:focus {
  border-color: var(--accent-dim);
}

.modal-hint {
  font-size: 11px;
  color: var(--text-dim);
  margin-top: 10px;
  line-height: 1.5;
}

.modal-footer {
  display: flex;
  gap: 10px;
  margin-top: 20px;
}

.btn {
  flex: 1;
  padding: 14px 0;
  border: none;
  border-radius: var(--radius-xs);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s ease;
  user-select: none;
}

.btn-primary {
  background: linear-gradient(135deg, var(--user-bubble-start), var(--user-bubble-end));
  color: #fff;
}

.btn-primary:active {
  opacity: 0.85;
}

.btn-ghost {
  background: rgba(255, 255, 255, 0.06);
  color: var(--text-secondary);
}

.btn-ghost:active {
  background: rgba(255, 255, 255, 0.1);
}

/* ========== Toast ========== */
.toast {
  position: fixed;
  top: calc(24px + env(safe-area-inset-top, 0px));
  left: 50%;
  transform: translateX(-50%) translateY(-20px);
  padding: 10px 20px;
  background: #1a1a2e;
  border: 1px solid var(--card-border);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-size: 13px;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s ease;
  z-index: 200;
  white-space: nowrap;
}

.toast.show {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
}

.toast.error {
  border-color: rgba(248, 113, 113, 0.3);
  color: var(--danger);
}

/* ========== Page Switching ========== */
.page {
  position: fixed;
  inset: 0;
  z-index: 1;
  display: flex;
  width: 100%;
  height: 100vh;
  height: 100dvh;
  opacity: 0;
  visibility: hidden;
  transform: translateX(-8%);
  transition: opacity 0.3s ease, transform 0.3s ease, visibility 0.3s;
  pointer-events: none;
}

.page.active {
  opacity: 1;
  visibility: visible;
  transform: translateX(0);
  pointer-events: auto;
}

/* ========== Character Select Page ========== */
.select-container {
  width: 100%;
  padding: calc(40px + env(safe-area-inset-top, 0px)) max(20px, env(safe-area-inset-right, 0px)) max(20px, env(safe-area-inset-bottom, 0px)) max(20px, env(safe-area-inset-left, 0px));
  display: flex;
  flex-direction: column;
  align-items: center;
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
}

.select-header {
  text-align: center;
  margin-bottom: 40px;
  animation: titleFadeDown 0.5s ease both;
}

.select-title {
  font-size: 28px;
  font-weight: 700;
  letter-spacing: 2px;
  background: linear-gradient(135deg, var(--text-primary), var(--glow-purple));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  text-shadow: none;
  filter: drop-shadow(0 0 30px rgba(192, 132, 252, 0.15));
}

.select-deco {
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 16px auto 0;
  width: 60px;
}

.select-deco span {
  width: 6px;
  height: 6px;
  background: var(--glow-purple);
  border-radius: 1px;
  transform: rotate(45deg);
  opacity: 0.5;
  box-shadow: -16px 0 0 -1px var(--glow-pink), 16px 0 0 -1px var(--glow-pink);
}

.select-subtitle {
  font-size: 13px;
  color: var(--text-dim);
  margin-top: 14px;
  letter-spacing: 2px;
}

.char-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
  width: 100%;
}

.char-card {
  background: var(--card-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-md);
  padding: 20px 16px;
  cursor: pointer;
  transition: all 0.25s ease;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 12px;
  user-select: none;
}

.char-card:active {
  transform: scale(0.97);
  border-color: var(--accent-dim);
}

.char-card-avatar-wrap {
  position: relative;
  width: 72px;
  height: 72px;
  border-radius: 50%;
  overflow: hidden;
  flex-shrink: 0;
  border: 2px solid rgba(255, 255, 255, 0.1);
}

.char-card-avatar {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.char-card-info {
  min-width: 0;
}

.char-card-name {
  font-size: 16px;
  font-weight: 600;
  color: var(--text-primary);
}

.char-card-title {
  font-size: 11px;
  color: var(--text-secondary);
  margin-top: 3px;
}

.char-card-tagline {
  font-size: 12px;
  color: var(--text-dim);
  margin-top: 8px;
  font-style: italic;
  line-height: 1.5;
}

/* ========== Gender Select ========== */
.gender-select {
  display: flex;
  flex-direction: column;
  gap: 20px;
  justify-content: center;
  align-items: center;
  width: 100%;
  max-width: 360px;
  margin-bottom: 40px;
}

.gender-btn {
  width: 100%;
  padding: 32px 28px;
  border-radius: 20px;
  background: var(--card-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--card-border);
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  display: flex;
  flex-direction: column;
  align-items: center;
  color: var(--text-primary);
  user-select: none;
  position: relative;
  overflow: hidden;
  min-height: 140px;
  justify-content: center;
  animation: genderCardEnter 0.6s cubic-bezier(0.16, 1, 0.3, 1) both;
}

.gender-btn:nth-child(1) {
  animation-delay: 0.1s;
}

.gender-btn:nth-child(2) {
  animation-delay: 0.25s;
}

/* Female card warm glow */
.gender-btn[data-gender="female"] {
  background: radial-gradient(ellipse at bottom, rgba(249, 168, 212, 0.08), transparent 70%), var(--card-bg);
}

/* Male card cool glow */
.gender-btn[data-gender="male"] {
  background: radial-gradient(ellipse at bottom, rgba(96, 165, 250, 0.08), transparent 70%), var(--card-bg);
}

/* Rotating gradient border */
.gender-btn::before {
  content: '';
  position: absolute;
  inset: -1px;
  border-radius: inherit;
  padding: 1px;
  background: conic-gradient(from var(--border-angle, 0deg), transparent 30%, var(--glow-purple) 50%, var(--glow-pink) 60%, transparent 80%);
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  opacity: 0.4;
  animation: borderRotate 6s linear infinite;
  pointer-events: none;
}

.gender-btn[data-gender="male"]::before {
  background: conic-gradient(from var(--border-angle, 0deg), transparent 30%, #60a5fa 50%, var(--glow-purple) 60%, transparent 80%);
}

/* Shimmer sweep effect */
.gender-btn::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(105deg, transparent 40%, rgba(255, 255, 255, 0.04) 44%, rgba(255, 255, 255, 0.1) 50%, rgba(255, 255, 255, 0.04) 56%, transparent 60%);
  background-size: 250% 100%;
  animation: shimmerSweep 5s ease-in-out infinite;
  pointer-events: none;
  border-radius: inherit;
}

.gender-btn:active {
  transform: scale(0.97);
  border-color: var(--accent-dim);
}

.gender-btn:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 4px;
}

/* Card content area */
.gender-card-content {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}

.gender-btn-icon {
  font-size: 14px;
  line-height: 1;
  opacity: 0.5;
}

.gender-btn[data-gender="female"] .gender-btn-icon {
  color: var(--glow-pink);
}

.gender-btn[data-gender="male"] .gender-btn-icon {
  color: #60a5fa;
}

.gender-btn-label {
  font-size: 24px;
  font-weight: 700;
  letter-spacing: 4px;
}

.gender-btn[data-gender="female"] .gender-btn-label {
  text-shadow: 0 0 24px rgba(249, 168, 212, 0.3);
}

.gender-btn[data-gender="male"] .gender-btn-label {
  text-shadow: 0 0 24px rgba(96, 165, 250, 0.3);
}

.gender-btn-subtitle {
  font-size: 13px;
  color: var(--text-dim);
  font-style: italic;
  letter-spacing: 0.5px;
  margin-top: 2px;
}

.gender-card-divider {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: 8px;
  opacity: 0.4;
}

.divider-line {
  width: 32px;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--text-dim), transparent);
}

.hidden {
  display: none !important;
}

/* ========== Responsive: Desktop Enhancement ========== */
@media (min-width: 768px) {
  .card {
    max-width: 520px;
    max-height: 900px;
    margin: 0 auto;
    border-radius: var(--radius-lg);
    box-shadow: 0 0 60px rgba(0, 0, 0, 0.4);
    border: 1px solid var(--card-border);
  }

  .card-header {
    padding: 18px 20px;
  }

  .chat-area {
    padding: 16px 20px;
  }

  .input-area {
    padding: 14px 20px 20px;
  }

  .select-container {
    max-width: 560px;
    margin: 0 auto;
    padding: 40px 20px;
  }

  .gender-select {
    flex-direction: row;
    max-width: 100%;
  }

  .gender-btn {
    flex: 1;
    min-height: 200px;
  }
}

/* ========== Hover: Mouse devices only ========== */
@media (hover: hover) and (pointer: fine) {
  .icon-btn:hover {
    background: rgba(255, 255, 255, 0.08);
    color: var(--text-secondary);
  }

  .send-btn:hover {
    opacity: 1;
    transform: scale(1.05);
  }

  .char-card:hover {
    border-color: var(--accent-dim);
    transform: translateY(-4px);
    box-shadow: 0 8px 30px rgba(167, 139, 250, 0.12);
  }

  .char-card:hover .char-card-avatar-wrap {
    border-color: var(--accent-dim);
  }

  .gender-btn:hover {
    transform: translateY(-6px) scale(1.02);
    border-color: var(--accent-dim);
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3), 0 0 40px rgba(167, 139, 250, 0.12);
  }

  .gender-btn:hover::before {
    opacity: 0.8;
  }

  .gender-btn[data-gender="female"]:hover {
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3), 0 0 40px rgba(249, 168, 212, 0.15);
  }

  .gender-btn[data-gender="male"]:hover {
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3), 0 0 40px rgba(96, 165, 250, 0.15);
  }

  .btn-primary:hover {
    opacity: 0.9;
  }

  .btn-ghost:hover {
    background: rgba(255, 255, 255, 0.1);
  }
}