/* ===== 全局重置 ===== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: 'Microsoft YaHei', 'PingFang SC', sans-serif;
  background: linear-gradient(135deg, #0a0e27 0%, #0d1b3e 50%, #0a2040 100%);
  min-height: 100vh;
  color: #e0f0ff;
}

.page-wrapper {
  max-width: 960px;
  margin: 0 auto;
  padding: 24px 16px 40px;
}

/* ===== 标题 ===== */
.title {
  text-align: center;
  font-size: 2rem;
  font-weight: 700;
  color: #7dd3fc;
  text-shadow: 0 0 20px rgba(125, 211, 252, 0.5);
  margin-bottom: 6px;
}

.subtitle {
  text-align: center;
  font-size: 0.9rem;
  color: #94a3b8;
  margin-bottom: 24px;
}

/* ===== 海洋容器 ===== */
.ocean-container {
  position: relative;
  width: 100%;
  height: 480px;
  background: linear-gradient(
    to bottom,
    #0ea5e9 0%,
    #0284c7 8%,
    #0369a1 20%,
    #075985 40%,
    #0c4a6e 65%,
    #082f49 85%,
    #041f30 100%
  );
  border-radius: 20px;
  overflow: hidden;
  border: 2px solid rgba(125, 211, 252, 0.3);
  box-shadow: 0 0 40px rgba(14, 165, 233, 0.2), inset 0 0 60px rgba(0,0,0,0.3);
  margin-bottom: 24px;
}

/* ===== 水面波纹 ===== */
.surface-waves {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 40px;
  z-index: 10;
  overflow: hidden;
}

.wave {
  position: absolute;
  width: 200%;
  height: 40px;
  background: rgba(255, 255, 255, 0.08);
  border-radius: 50%;
  top: -20px;
}

.wave1 {
  animation: waveMove 4s linear infinite;
  background: rgba(255, 255, 255, 0.1);
}

.wave2 {
  animation: waveMove 6s linear infinite reverse;
  background: rgba(125, 211, 252, 0.08);
  top: -15px;
}

.wave3 {
  animation: waveMove 8s linear infinite;
  background: rgba(255, 255, 255, 0.05);
  top: -10px;
}

@keyframes waveMove {
  0% { transform: translateX(0); }
  100% { transform: translateX(-50%); }
}

/* ===== 气泡 ===== */
.bubbles-container {
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 5;
}

.bubble {
  position: absolute;
  border-radius: 50%;
  background: radial-gradient(circle at 30% 30%, rgba(255,255,255,0.6), rgba(125,211,252,0.2));
  border: 1px solid rgba(255,255,255,0.3);
  animation: bubbleRise linear infinite;
}

@keyframes bubbleRise {
  0% { transform: translateY(0) translateX(0); opacity: 0.8; }
  50% { transform: translateY(-50%) translateX(8px); opacity: 0.5; }
  100% { transform: translateY(-100%) translateX(-4px); opacity: 0; }
}

/* ===== 深度标尺 ===== */
.depth-ruler {
  position: absolute;
  right: 12px;
  top: 0;
  bottom: 0;
  width: 40px;
  z-index: 8;
}

.ruler-mark {
  position: absolute;
  right: 0;
  transform: translateY(-50%);
  display: flex;
  align-items: center;
  gap: 4px;
}

.ruler-mark::before {
  content: '';
  display: block;
  width: 8px;
  height: 1px;
  background: rgba(125, 211, 252, 0.4);
}

.ruler-mark span {
  font-size: 0.65rem;
  color: rgba(125, 211, 252, 0.5);
  white-space: nowrap;
}

/* ===== 潜水艇包装器 ===== */
.submarine-wrapper {
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  top: 5%;
  transition: top 1.8s cubic-bezier(0.4, 0, 0.2, 1);
  z-index: 20;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
}

/* ===== 潜水艇主体 ===== */
.submarine {
  position: relative;
  width: 220px;
  height: 80px;
  filter: drop-shadow(0 4px 12px rgba(0,0,0,0.5));
}

.sub-body {
  position: absolute;
  left: 20px;
  top: 20px;
  width: 180px;
  height: 50px;
  background: linear-gradient(135deg, #fbbf24 0%, #f59e0b 40%, #d97706 70%, #b45309 100%);
  border-radius: 50px;
  box-shadow:
    inset 0 4px 8px rgba(255,255,255,0.3),
    inset 0 -4px 8px rgba(0,0,0,0.3),
    0 4px 16px rgba(0,0,0,0.4);
}

/* 指挥塔 */
.conning-tower {
  position: absolute;
  top: -28px;
  left: 55px;
  width: 44px;
  height: 30px;
  background: linear-gradient(135deg, #f59e0b, #d97706);
  border-radius: 8px 8px 0 0;
  box-shadow: inset 0 2px 4px rgba(255,255,255,0.2);
}

.periscope {
  position: absolute;
  top: -18px;
  left: 50%;
  transform: translateX(-50%);
  width: 4px;
  height: 20px;
  background: #92400e;
  border-radius: 2px;
  transition: transform 0.5s ease;
}

.periscope::after {
  content: '';
  position: absolute;
  top: 0;
  left: -4px;
  width: 12px;
  height: 4px;
  background: #92400e;
  border-radius: 2px;
}

.antenna {
  position: absolute;
  top: -10px;
  right: 8px;
  width: 2px;
  height: 12px;
  background: #78350f;
  border-radius: 1px;
}

/* 舷窗 */
.porthole {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: #1e3a5f;
  border: 3px solid #92400e;
  box-shadow: inset 0 0 6px rgba(125, 211, 252, 0.5), 0 0 4px rgba(0,0,0,0.5);
  overflow: hidden;
}

.porthole-inner {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  background: radial-gradient(circle at 35% 35%, rgba(125,211,252,0.6), rgba(14,165,233,0.2));
  animation: portholePulse 3s ease-in-out infinite;
}

@keyframes portholePulse {
  0%, 100% { opacity: 0.7; }
  50% { opacity: 1; }
}

.porthole-1 { left: 30px; }
.porthole-2 { left: 60px; }

/* 螺旋桨 */
.propeller {
  position: absolute;
  right: -14px;
  top: 50%;
  transform: translateY(-50%);
  width: 28px;
  height: 28px;
  animation: propellerSpin 0.4s linear infinite;
}

.blade {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 12px;
  height: 4px;
  background: linear-gradient(90deg, #92400e, #b45309);
  border-radius: 2px;
  transform-origin: 0 50%;
}

.blade-1 { transform: translateY(-50%) rotate(0deg); }
.blade-2 { transform: translateY(-50%) rotate(90deg); }
.blade-3 { transform: translateY(-50%) rotate(180deg); }
.blade-4 { transform: translateY(-50%) rotate(270deg); }

@keyframes propellerSpin {
  from { transform: translateY(-50%) rotate(0deg); }
  to { transform: translateY(-50%) rotate(360deg); }
}

/* 舵 */
.rudder-front {
  position: absolute;
  left: 10px;
  top: -8px;
  width: 20px;
  height: 8px;
  background: #d97706;
  border-radius: 2px 2px 0 0;
  transform: skewX(-10deg);
}

.rudder-rear {
  position: absolute;
  right: 8px;
  top: -10px;
  width: 16px;
  height: 10px;
  background: #d97706;
  border-radius: 2px 2px 0 0;
}

/* ===== 压载水舱 ===== */
.ballast-tanks {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  pointer-events: none;
}

.ballast-tank {
  position: absolute;
  width: 36px;
  height: 44px;
  border: 2px solid rgba(146, 64, 14, 0.8);
  border-radius: 6px;
  background: rgba(0, 0, 0, 0.3);
  overflow: hidden;
  top: 50%;
  transform: translateY(-50%);
}

.tank-left {
  left: 28px;
  top: calc(50% + 28px);
}

.tank-right {
  right: 28px;
  top: calc(50% + 28px);
}

.tank-label {
  position: absolute;
  top: -18px;
  left: 50%;
  transform: translateX(-50%);
  font-size: 0.55rem;
  color: rgba(251, 191, 36, 0.8);
  white-space: nowrap;
  pointer-events: none;
}

.tank-water {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 0%;
  background: linear-gradient(to top, rgba(14, 165, 233, 0.9), rgba(56, 189, 248, 0.6));
  transition: height 1.5s cubic-bezier(0.4, 0, 0.2, 1);
  border-radius: 0 0 4px 4px;
}

.tank-bubbles {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

/* ===== 状态标签 ===== */
.status-badge {
  padding: 4px 14px;
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 600;
  background: rgba(14, 165, 233, 0.2);
  border: 1px solid rgba(125, 211, 252, 0.4);
  color: #7dd3fc;
  transition: all 0.5s ease;
  white-space: nowrap;
}

.status-badge.floating { background: rgba(34, 197, 94, 0.2); border-color: rgba(74, 222, 128, 0.5); color: #4ade80; }
.status-badge.hovering { background: rgba(59, 130, 246, 0.2); border-color: rgba(96, 165, 250, 0.5); color: #60a5fa; }
.status-badge.sinking  { background: rgba(251, 146, 60, 0.2); border-color: rgba(251, 146, 60, 0.5); color: #fb923c; }
.status-badge.bottom   { background: rgba(239, 68, 68, 0.2); border-color: rgba(248, 113, 113, 0.5); color: #f87171; }

/* ===== 海底 ===== */
.seabed {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 60px;
  background: linear-gradient(to top, #1a0a00, #2d1500, #3d1f00);
  border-radius: 0 0 18px 18px;
}

.seabed-rocks {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 20px;
  background: radial-gradient(ellipse 30px 12px at 10% 100%, #4a2800 50%, transparent 51%),
              radial-gradient(ellipse 20px 10px at 25% 100%, #3d2000 50%, transparent 51%),
              radial-gradient(ellipse 40px 15px at 45% 100%, #5a3200 50%, transparent 51%),
              radial-gradient(ellipse 25px 12px at 65% 100%, #4a2800 50%, transparent 51%),
              radial-gradient(ellipse 35px 14px at 82% 100%, #3d2000 50%, transparent 51%),
              radial-gradient(ellipse 20px 10px at 95% 100%, #5a3200 50%, transparent 51%);
}

.seabed-plants {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 50px;
  display: flex;
  align-items: flex-end;
  gap: 0;
}

.seaweed {
  position: absolute;
  bottom: 0;
  width: 8px;
  border-radius: 4px;
  background: linear-gradient(to top, #166534, #15803d, #16a34a);
  transform-origin: bottom center;
  animation: seaweedSway 3s ease-in-out infinite;
}

.sw1 { left: 8%; height: 30px; animation-delay: 0s; }
.sw2 { left: 20%; height: 22px; animation-delay: 0.5s; }
.sw3 { left: 40%; height: 35px; animation-delay: 1s; }
.sw4 { left: 60%; height: 28px; animation-delay: 0.3s; }
.sw5 { left: 78%; height: 32px; animation-delay: 0.8s; }

@keyframes seaweedSway {
  0%, 100% { transform: rotate(-8deg); }
  50% { transform: rotate(8deg); }
}

.fish {
  position: absolute;
  font-size: 1.2rem;
  animation: fishSwim linear infinite;
  bottom: 60px;
}

.fish1 { animation-duration: 12s; animation-delay: 0s; bottom: 80px; }
.fish2 { animation-duration: 18s; animation-delay: -6s; bottom: 120px; }
.fish3 { animation-duration: 22s; animation-delay: -10s; bottom: 160px; }

@keyframes fishSwim {
  0% { left: -5%; transform: scaleX(1); }
  49% { left: 105%; transform: scaleX(1); }
  50% { left: 105%; transform: scaleX(-1); }
  99% { left: -5%; transform: scaleX(-1); }
  100% { left: -5%; transform: scaleX(1); }
}

/* ===== 控制面板 ===== */
.control-panel {
  background: rgba(15, 23, 42, 0.8);
  border: 1px solid rgba(125, 211, 252, 0.2);
  border-radius: 16px;
  overflow: hidden;
  margin-bottom: 24px;
  backdrop-filter: blur(10px);
}

.panel-header {
  background: linear-gradient(90deg, rgba(14, 165, 233, 0.2), rgba(59, 130, 246, 0.1));
  padding: 12px 20px;
  font-size: 1rem;
  font-weight: 600;
  color: #7dd3fc;
  display: flex;
  align-items: center;
  gap: 8px;
  border-bottom: 1px solid rgba(125, 211, 252, 0.15);
}

.panel-body {
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

/* ===== 水舱控制 ===== */
.tanks-control {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.tank-control-item {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(125, 211, 252, 0.1);
  border-radius: 12px;
  padding: 14px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.tank-control-header {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 0.85rem;
  color: #cbd5e1;
}

.tank-icon { font-size: 1rem; }

.tank-percent {
  margin-left: auto;
  font-weight: 700;
  color: #38bdf8;
  font-size: 0.9rem;
  min-width: 36px;
  text-align: right;
}

.slider-wrapper {
  display: flex;
  align-items: center;
  gap: 8px;
}

.slider-label {
  font-size: 0.7rem;
  color: #64748b;
  white-space: nowrap;
}

.tank-slider {
  flex: 1;
  -webkit-appearance: none;
  appearance: none;
  height: 6px;
  border-radius: 3px;
  background: linear-gradient(to right, #0ea5e9 0%, #0ea5e9 var(--val, 0%), rgba(255,255,255,0.1) var(--val, 0%));
  outline: none;
  cursor: pointer;
}

.tank-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: linear-gradient(135deg, #38bdf8, #0ea5e9);
  border: 2px solid rgba(255,255,255,0.3);
  box-shadow: 0 0 8px rgba(14, 165, 233, 0.5);
  cursor: pointer;
  transition: transform 0.2s;
}

.tank-slider::-webkit-slider-thumb:hover {
  transform: scale(1.2);
}

.tank-visual-mini {
  height: 8px;
  background: rgba(255,255,255,0.06);
  border-radius: 4px;
  overflow: hidden;
  border: 1px solid rgba(125, 211, 252, 0.1);
}

.tank-mini-water {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, #0ea5e9, #38bdf8);
  border-radius: 4px;
  transition: width 1.5s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ===== 快捷按钮 ===== */
.quick-buttons {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
}

.quick-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  padding: 12px 8px;
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: 12px;
  background: rgba(255,255,255,0.04);
  cursor: pointer;
  transition: all 0.25s ease;
  color: #e2e8f0;
}

.quick-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(0,0,0,0.3);
}

.quick-btn:active { transform: translateY(0); }

.btn-icon { font-size: 1.4rem; }
.btn-text { font-size: 0.85rem; font-weight: 600; }
.btn-desc { font-size: 0.65rem; color: #64748b; }

.btn-float { border-color: rgba(74, 222, 128, 0.3); }
.btn-float:hover { background: rgba(34, 197, 94, 0.15); border-color: rgba(74, 222, 128, 0.6); }

.btn-hover { border-color: rgba(96, 165, 250, 0.3); }
.btn-hover:hover { background: rgba(59, 130, 246, 0.15); border-color: rgba(96, 165, 250, 0.6); }

.btn-sink { border-color: rgba(251, 146, 60, 0.3); }
.btn-sink:hover { background: rgba(249, 115, 22, 0.15); border-color: rgba(251, 146, 60, 0.6); }

.btn-bottom { border-color: rgba(248, 113, 113, 0.3); }
.btn-bottom:hover { background: rgba(239, 68, 68, 0.15); border-color: rgba(248, 113, 113, 0.6); }

.quick-btn.active {
  box-shadow: 0 0 16px rgba(14, 165, 233, 0.4);
}

.btn-float.active { background: rgba(34, 197, 94, 0.2); border-color: #4ade80; }
.btn-hover.active { background: rgba(59, 130, 246, 0.2); border-color: #60a5fa; }
.btn-sink.active  { background: rgba(249, 115, 22, 0.2); border-color: #fb923c; }
.btn-bottom.active{ background: rgba(239, 68, 68, 0.2); border-color: #f87171; }

/* ===== 状态信息 ===== */
.status-info {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
}

.info-item {
  background: rgba(255,255,255,0.04);
  border: 1px solid rgba(125, 211, 252, 0.1);
  border-radius: 10px;
  padding: 10px 12px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.info-label {
  font-size: 0.7rem;
  color: #64748b;
}

.info-value {
  font-size: 0.9rem;
  font-weight: 600;
  color: #38bdf8;
}

/* ===== 原理说明 ===== */
.principle-card {
  background: rgba(15, 23, 42, 0.7);
  border: 1px solid rgba(125, 211, 252, 0.15);
  border-radius: 16px;
  padding: 20px;
  margin-bottom: 24px;
}

.principle-card h3 {
  font-size: 1rem;
  color: #7dd3fc;
  margin-bottom: 16px;
}

.principle-steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
}

.step {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  text-align: center;
  padding: 12px;
  background: rgba(255,255,255,0.03);
  border-radius: 10px;
  border: 1px solid rgba(255,255,255,0.06);
}

.step-icon { font-size: 1.6rem; }

.step-content strong {
  display: block;
  font-size: 0.85rem;
  color: #cbd5e1;
  margin-bottom: 4px;
}

.step-content p {
  font-size: 0.72rem;
  color: #64748b;
  line-height: 1.5;
}

/* ===== 页脚 ===== */
footer {
  text-align: center;
  color: #475569;
  font-size: 0.8rem;
  padding-top: 8px;
}

footer a { text-decoration: none; }
footer a:hover { text-decoration: underline; }

/* ===== 响应式 ===== */
@media (max-width: 640px) {
  .title { font-size: 1.5rem; }
  .ocean-container { height: 360px; }
  .tanks-control { grid-template-columns: 1fr; }
  .quick-buttons { grid-template-columns: repeat(2, 1fr); }
  .status-info { grid-template-columns: repeat(2, 1fr); }
  .principle-steps { grid-template-columns: repeat(2, 1fr); }
  .submarine { width: 160px; height: 60px; }
  .sub-body { left: 14px; top: 14px; width: 132px; height: 38px; }
}