/* ==========================================================
   深空制图仪 · 视觉层
   深靛蓝的夜空 + 象牙白的陆地 + 一点黄铜色信号
   （不用霓虹青绿，不做 HUD 边框，让画面自己说话）
   ========================================================== */

:root {
  --void: #04060c;                 /* 视场之外 */
  --ink: #e9e5da;                  /* 数据白（偏暖，像仪器刻度） */
  --ink-dim: rgba(233, 229, 218, 0.68);
  --ink-faint: rgba(233, 229, 218, 0.52);
  --brass: #e3a04c;                /* 唯一的暖色信号 */
  --rule: rgba(233, 229, 218, 0.20);

  --sans: "PingFang SC", "Helvetica Neue", Helvetica, sans-serif;
  --mono: "SF Mono", "Menlo", "PingFang SC", monospace;
}

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

html, body {
  height: 100%;
  overflow: hidden;
  background: var(--void);
  color: var(--ink);
  font-family: var(--sans);
  -webkit-font-smoothing: antialiased;
}

canvas { display: block; }

/* 左侧渐隐底：只帮助文字从地球和星空中分离，不做卡片 */
#left-scrim {
  position: fixed;
  z-index: 1;
  inset: 0 auto 0 0;
  width: min(280px, 30vw);
  pointer-events: none;
  background: linear-gradient(90deg, rgba(2, 4, 9, 0.80), rgba(2, 4, 9, 0.30) 62%, transparent);
}

/* ---------- 左上角仪器读数 ---------- */
#hud {
  position: fixed;
  z-index: 3;
  left: 30px;
  top: 26px;
  width: 208px;
  pointer-events: none;
}

#hud h1 {
  font-size: 17px;
  font-weight: 500;
  letter-spacing: 0.08em;
}

#hud .serial {
  margin-top: 5px;
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--ink-dim);
}

#hud hr {
  margin: 14px 0 12px;
  border: 0;
  height: 1px;
  width: 44px;
  background: var(--rule);
}

#hud dl { font-size: 12px; }

#hud dl > div {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding: 3px 0;
}

#hud dt {
  font-size: 11.5px;
  letter-spacing: 0.04em;
  color: var(--ink-dim);
}

#hud dd {
  font-family: var(--mono);
  font-size: 12px;
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.02em;
  color: var(--ink);
  text-align: right;
}

#hud #warn {
  margin-top: 10px;
  font-size: 11.5px;
  line-height: 1.7;
  color: var(--brass);
  min-height: 1px;
}

#hud .hud-break {
  margin-top: 7px;
  padding-top: 10px;
  border-top: 1px solid var(--rule);
}

/* ---------- 底部操作提示：安静，不抢戏 ---------- */
#hint {
  position: fixed;
  z-index: 3;
  left: 30px;
  bottom: 24px;
  max-width: min(560px, calc(100vw - 60px));
  font-size: 12px;
  line-height: 1.9;
  letter-spacing: 0.03em;
  color: var(--ink-faint);
  pointer-events: none;
}

/* ---------- 左侧按键提示：与手势提示分开 ---------- */
#key-hint {
  position: fixed;
  z-index: 3;
  left: 30px;
  top: 52%;
  transform: translateY(-50%);
  width: 150px;
  font-size: 11.5px;
  line-height: 1.75;
  letter-spacing: 0.03em;
  color: var(--ink-faint);
  pointer-events: none;
}

#key-hint span {
  display: flex;
  align-items: baseline;
  gap: 8px;
}

#key-hint b {
  width: 32px;
  font-weight: 500;
  color: var(--ink-dim);
}

body.ui-hidden #hud,
body.ui-hidden #hint,
body.ui-hidden #key-hint,
body.ui-hidden #tutorial-button,
body.ui-hidden #observer-city,
body.ui-hidden #meteor-shower-label,
body.ui-hidden #observer-toast,
body.ui-hidden #left-scrim {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

/* ---------- 详细教程 ---------- */
#tutorial-button {
  position: fixed;
  z-index: 4;
  left: 30px;
  bottom: 122px;
  min-height: 36px;
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 7px 12px;
  border: 1px solid var(--rule);
  border-radius: 2px;
  background: rgba(4, 6, 12, 0.42);
  color: var(--ink-dim);
  font-family: var(--sans);
  font-size: 11px;
  letter-spacing: 0.08em;
  cursor: pointer;
  pointer-events: auto;
  transition: color 0.2s ease, border-color 0.2s ease, background 0.2s ease;
}

#tutorial-button svg {
  width: 15px;
  height: 15px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.5;
  stroke-linecap: round;
  stroke-linejoin: round;
}

#tutorial-button:hover {
  color: var(--ink);
  border-color: rgba(227, 160, 76, 0.62);
  background: rgba(4, 6, 12, 0.72);
}

#tutorial-overlay {
  position: fixed;
  inset: 0;
  z-index: 20;
  display: grid;
  place-items: center;
  overflow: hidden;
  padding: 22px;
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  background: rgba(2, 4, 9, 0.78);
  backdrop-filter: blur(9px);
  transition: opacity 0.24s ease, visibility 0.24s ease;
}

#tutorial-overlay.show {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

.tutorial-hand-sprite {
  position: absolute;
  width: 0;
  height: 0;
  overflow: hidden;
  pointer-events: none;
}

#tutorial-panel {
  width: min(980px, calc(100vw - 44px));
  height: min(86vh, 760px);
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  padding: clamp(18px, 3vw, 30px);
  border: 1px solid rgba(233, 229, 218, 0.18);
  border-radius: 2px;
  background:
    linear-gradient(140deg, rgba(18, 25, 40, 0.96), rgba(5, 8, 15, 0.98) 62%),
    radial-gradient(circle at 18% 0%, rgba(227, 160, 76, 0.08), transparent 34%);
  box-shadow: 0 24px 80px rgba(0, 0, 0, 0.64);
}

.tutorial-head {
  flex: 0 0 auto;
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 24px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--rule);
}

.tutorial-head h2 {
  font-size: clamp(20px, 2vw, 25px);
  font-weight: 500;
  letter-spacing: 0.08em;
}

.tutorial-head p {
  margin-top: 4px;
  color: var(--ink-dim);
  font-size: 12px;
  letter-spacing: 0.05em;
}

#tutorial-close {
  flex: 0 0 auto;
  min-width: 38px;
  min-height: 32px;
  padding: 6px 9px;
  border: 1px solid var(--rule);
  border-radius: 2px;
  background: transparent;
  color: var(--ink-dim);
  font-family: var(--sans);
  font-size: 11px;
  cursor: pointer;
}

#tutorial-close:hover { color: var(--ink); border-color: var(--brass); }

.tutorial-pace {
  flex: 0 0 auto;
  margin: 11px 0 0;
  padding: 8px 12px;
  border-left: 2px solid var(--brass);
  color: var(--ink-dim);
  font-size: 11.5px;
  line-height: 1.6;
}

.tutorial-pace strong { color: var(--ink); font-weight: 500; }

.tutorial-list {
  flex: 1 1 auto;
  min-height: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  grid-template-rows: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: 12px;
  overflow: hidden;
  border: 1px solid var(--rule);
  background: var(--rule);
}

.tutorial-step {
  display: grid;
  grid-template-columns: minmax(105px, 0.78fr) minmax(0, 1.22fr);
  gap: clamp(10px, 1.8vw, 18px);
  align-items: center;
  min-width: 0;
  min-height: 0;
  padding: 13px 15px;
  overflow: hidden;
  background: rgba(8, 13, 22, 0.94);
}

.tutorial-figure {
  display: flex;
  align-items: center;
  justify-content: center;
  min-width: 0;
  min-height: 0;
  height: 100%;
  padding-right: 11px;
  border-right: 1px solid var(--rule);
}

.tutorial-figure svg {
  width: 100%;
  max-width: 150px;
  height: auto;
  overflow: visible;
}

.tutorial-figure .ink {
  fill: none;
  stroke: rgba(233, 229, 218, 0.7);
  stroke-width: 5;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.tutorial-figure .ink-thin {
  fill: none;
  stroke: rgba(233, 229, 218, 0.34);
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.tutorial-figure .brass { fill: var(--brass); stroke: var(--brass); }

.tutorial-figure .brass-line {
  fill: none;
  stroke: var(--brass);
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.tutorial-figure text {
  fill: rgba(233, 229, 218, 0.56);
  font-family: var(--sans);
  font-size: 10px;
  letter-spacing: 0.03em;
}

.tutorial-figure .five-tip-lines {
  fill: none;
  stroke: var(--brass);
  stroke-width: 1.5;
  stroke-dasharray: 3 4;
  opacity: 0.82;
}

.tutorial-copy h3 {
  margin-bottom: 5px;
  color: var(--ink);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.06em;
}

.tutorial-copy p {
  max-width: 64ch;
  color: var(--ink-dim);
  font-size: 11.5px;
  line-height: 1.65;
}

.tutorial-tip { margin-top: 6px; font-size: 10.5px; }
.tutorial-tip span {
  color: var(--brass);
  letter-spacing: 0.1em;
}

/* ---------- 观察者模式城市牌：屏幕下方，中英文上下排列 ---------- */
#observer-city {
  position: fixed;
  z-index: 3;
  left: 50%;
  bottom: 108px;
  transform: translate(-50%, 12px);
  opacity: 0;
  pointer-events: none;
  text-align: center;
  transition: opacity 0.35s ease, transform 0.35s ease, bottom 0.35s ease;
}

#observer-city.show {
  opacity: 1;
  transform: translate(-50%, 0);
}

#observer-city-zh {
  font-size: clamp(36px, 4.2vw, 48px);
  font-weight: 500;
  letter-spacing: 0.12em;
  color: var(--ink);
  text-shadow: 0 0 18px rgba(233, 229, 218, 0.22), 0 2px 8px rgba(0, 0, 0, 0.7);
}

#observer-city-en {
  margin-top: 6px;
  font-size: clamp(15px, 1.45vw, 19px);
  font-weight: 400;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--brass);
  text-shadow: 0 0 12px rgba(227, 160, 76, 0.22);
}

/* ---------- 流星雨名称：与城市名牌同构，中英文上下排列 ---------- */
#meteor-shower-label {
  position: fixed;
  z-index: 3;
  left: 50%;
  bottom: 108px;
  transform: translate(-50%, 12px);
  opacity: 0;
  pointer-events: none;
  text-align: center;
  transition: opacity 0.35s ease, transform 0.35s ease;
}

#meteor-shower-label.show {
  opacity: 1;
  transform: translate(-50%, 0);
}

#meteor-shower-zh {
  font-size: clamp(34px, 4vw, 46px);
  font-weight: 500;
  letter-spacing: 0.14em;
  color: var(--ink);
  text-shadow: 0 0 18px rgba(180, 208, 236, 0.24), 0 2px 8px rgba(0, 0, 0, 0.72);
}

#meteor-shower-en {
  margin-top: 6px;
  font-size: clamp(14px, 1.35vw, 18px);
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--brass);
  text-shadow: 0 0 12px rgba(227, 160, 76, 0.22);
}

body.shower-active #observer-city { bottom: 224px; }

/* ---------- 观察者模式提示：短暂出现，不常驻 ---------- */
#observer-toast {
  position: fixed;
  z-index: 3;
  left: 50%;
  bottom: 72px;
  transform: translate(-50%, 8px);
  opacity: 0;
  pointer-events: none;
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--brass);
  text-shadow: 0 0 12px rgba(227, 160, 76, 0.28);
  transition: opacity 0.28s ease, transform 0.28s ease;
}

#observer-toast.show {
  opacity: 0.92;
  transform: translate(-50%, 0);
}

#observer-toast.camera-switch {
  bottom: 82px;
  font-size: clamp(18px, 2vw, 24px);
  font-weight: 500;
  letter-spacing: 0.18em;
  color: var(--ink);
  text-shadow: 0 0 18px rgba(233, 229, 218, 0.32), 0 2px 10px rgba(0, 0, 0, 0.72);
}

#observer-toast.camera-switch::before {
  content: "";
  display: inline-block;
  width: 7px;
  height: 7px;
  margin-right: 12px;
  border-radius: 50%;
  background: var(--brass);
  box-shadow: 0 0 14px rgba(227, 160, 76, 0.62);
  vertical-align: 0.08em;
}

#observer-toast.camera-switch.camera-off {
  color: var(--ink-dim);
  text-shadow: 0 2px 10px rgba(0, 0, 0, 0.72);
}

#observer-toast.camera-switch.camera-off::before {
  background: var(--ink-faint);
  box-shadow: none;
}

/* ---------- 光学质感：暗角 + 极细颗粒 ---------- */
#vignette {
  position: fixed;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(120% 90% at 50% 42%, rgba(4, 6, 12, 0) 40%, rgba(4, 6, 12, 0.62) 100%);
}

#grain {
  position: fixed;
  inset: 0;
  pointer-events: none;
  opacity: 0.05;
  mix-blend-mode: screen;
  background-image: url("data:image/svg+xml;utf8,\
<svg xmlns='http://www.w3.org/2000/svg' width='160' height='160'>\
<filter id='n'><feTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/>\
<feColorMatrix type='saturate' values='0'/></filter>\
<rect width='160' height='160' filter='url(%23n)'/></svg>");
}

/* 键盘焦点可见（无障碍） */
:focus-visible { outline: 1px solid var(--brass); outline-offset: 3px; }


@media (max-width: 760px) {
  #key-hint {
    top: auto;
    bottom: 118px;
    left: 18px;
    transform: none;
    width: auto;
    display: block;
  }
  #left-scrim { width: 72vw; }
  #hint .hint-detail,
  #hint .hint-break { display: none; }
  #hint {
    left: 18px;
    bottom: 20px;
    max-width: calc(100vw - 36px);
    font-size: 11.5px;
    line-height: 1.7;
  }
  #tutorial-button {
    left: 18px;
    bottom: 58px;
    min-height: 44px;
    padding: 9px 13px;
  }
  #tutorial-close { min-width: 44px; min-height: 44px; }
  #tutorial-overlay { padding: 6px; }
  #tutorial-panel {
    width: calc(100vw - 12px);
    height: calc(100vh - 12px);
    padding: 10px;
  }
  .tutorial-head { padding-bottom: 7px; }
  .tutorial-head h2 { font-size: 16px; }
  .tutorial-head p { font-size: 10px; }
  .tutorial-pace { margin-top: 6px; padding: 5px 7px; font-size: 9.5px; }
  .tutorial-list { margin-top: 6px; }
  .tutorial-step {
    grid-template-columns: 1fr;
    grid-template-rows: minmax(52px, 0.75fr) minmax(0, 1.25fr);
    gap: 4px;
    padding: 6px 7px;
  }
  .tutorial-figure {
    min-height: 0;
    padding: 0 0 4px;
    border-right: 0;
    border-bottom: 1px solid var(--rule);
  }
  .tutorial-figure svg { max-width: 86px; max-height: 58px; }
  .tutorial-copy h3 { margin-bottom: 2px; font-size: 10.5px; }
  .tutorial-copy p { font-size: 9px; line-height: 1.4; }
  .tutorial-tip { margin-top: 2px; font-size: 8.5px; }
}

@media (min-width: 761px) and (max-height: 720px) {
  #hud dl > div { padding: 2px 0; }
  #hud hr { margin: 10px 0 9px; }
  #key-hint {
    top: auto;
    bottom: 166px;
    transform: none;
  }
}


/* 手机横屏入口与安全区域，桌面保持原布局。 */
#landscape-button, #landscape-help { display: none; }
@media (pointer: coarse) and (max-width: 1100px) {
  #landscape-button {
    display: block; position: fixed; z-index: 4;
    right: max(16px, env(safe-area-inset-right));
    top: max(16px, env(safe-area-inset-top));
    min-height: 44px; padding: 9px 13px;
    color: var(--ink); background: rgba(4,6,12,.85);
    border: 1px solid var(--brass); border-radius: 4px; font: inherit;
  }
  #landscape-help:not([hidden]) {
    display: block; position: fixed; z-index: 4;
    top: max(68px, calc(env(safe-area-inset-top) + 52px));
    right: max(16px, env(safe-area-inset-right));
    width: min(240px, 65vw); padding: 12px;
    color: var(--ink); background: rgba(4,6,12,.95); font-size: 13px;
  }
  #key-hint { display: none; }
}
@media (pointer: coarse) and (orientation: landscape) and (max-height: 600px) {
  #hud { left: max(14px, env(safe-area-inset-left)); top: max(12px, env(safe-area-inset-top)); width: 145px; }
  #hud h1 { font-size: 18px; }
  #hud .serial, #hud hr, #hud dl > div:nth-child(n+4) { display: none; }
  #hud dl > div { padding: 2px 0; }
  #hint { display: none; }
  #tutorial-button { left: max(14px, env(safe-area-inset-left)); bottom: max(12px, env(safe-area-inset-bottom)); min-height: 44px; }
  #left-scrim { width: 180px; }
  #tutorial-panel { height: calc(100dvh - 12px); overflow-y: auto; }
  .tutorial-list { display: block; }
  .tutorial-step { display: grid; grid-template-columns: 110px 1fr; margin-bottom: 8px; min-height: 150px; }
}
body.ui-hidden #landscape-button, body.ui-hidden #landscape-help { display: none; }