/* === 智能導航 CSS - 最佳化版本 === */

/* =========================
   變數定義系統
========================= */
:root {
  /* 顏色系統 - 溫暖大地色系 */
  --nav-color-primary: #8B4513;
  --nav-color-secondary: #D2691E;
  --nav-color-accent: #F9A825;
  --nav-color-back: #C23B22;
  /* 返回：赭紅色 */
  --nav-color-section: #5D4037;
  /* 分區：深褐色 */
  --nav-color-home: #2C2416;
  /* 首頁：深巧克力色 */
  --nav-color-top: #8B4513;
  /* 頂部：棕色 */

  /* 背景與陰影系統 */
  --nav-bg-light: rgba(255, 255, 255, 0.92);
  --nav-bg-dark: rgba(40, 40, 40, 0.92);
  --nav-shadow: 0 4px 20px rgba(139, 69, 19, 0.15);
  --nav-border: rgba(139, 69, 19, 0.2);
  --nav-border-hover: rgba(249, 168, 37, 0.3);
  --nav-border-active: rgba(249, 168, 37, 0.5);

  /* 尺寸系統 */
  --nav-desktop-btn: 58px;
  --nav-desktop-icon: 28px;
  --nav-desktop-label-offset: 7px;
  --nav-mobile-core: 68px;
  --nav-mobile-item: 48px;
  --nav-mobile-offset: 75px;
  --nav-mobile-label-offset: 28px;

  /* 動畫系統 */
  --nav-transition: 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  --nav-animation-duration: 0.4s;
  --nav-float-duration: 4s;

  /* 定位系統 */
  --nav-desktop-top: clamp(80px, 10vh, 120px);
  --nav-desktop-bottom: clamp(70px, 8vh, 90px);
  --nav-desktop-left: 25px;
  --nav-desktop-right: 25px;
  --nav-mobile-safe: 20px;
}

/* 減少動畫偏好 */
@media (prefers-reduced-motion: reduce) {
  :root {
    --nav-transition: 0.1s ease;
    --nav-animation-duration: 0.1s;
    --nav-float-duration: 0s;
  }
}

/* =========================
   基礎樣式與容器
========================= */
.smart-nav-system {
  position: fixed;
  z-index: 99999;
  pointer-events: none;
  contain: layout style paint;
  will-change: transform;
  isolation: isolate;
}

.smart-nav-system * {
  pointer-events: auto;
  box-sizing: border-box;
}

/* 性能優化：GPU加速 */
.gpu-accelerate {
  transform: translateZ(0);
  backface-visibility: hidden;
}

/* 支持 backdrop-filter 的瀏覽器 */
@supports (backdrop-filter: blur(8px)) or (-webkit-backdrop-filter: blur(8px)) {

  .smart-nav-desktop-btn,
  .smart-nav-core,
  .smart-nav-item {
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
  }
}

/* =========================
   動畫定義
========================= */
@keyframes nav-float {

  0%,
  100% {
    transform: translateY(0) translateZ(0);
  }

  50% {
    transform: translateY(-6px) translateZ(0);
  }
}

@keyframes nav-ripple {
  0% {
    transform: scale(0) translateZ(0);
    opacity: 0.6;
  }

  100% {
    transform: scale(2) translateZ(0);
    opacity: 0;
  }
}

@keyframes nav-expand {
  0% {
    opacity: 0;
    transform: scale(0) translateZ(0);
  }

  70% {
    opacity: 0.7;
    transform: scale(1.1) translateZ(0);
  }

  100% {
    opacity: 1;
    transform: scale(1) translateZ(0);
  }
}

/* 減少動畫支持 */
@media (prefers-reduced-motion: reduce) {
  @keyframes nav-float {

    0%,
    100% {
      transform: translateY(0) translateZ(0);
    }
  }

  @keyframes nav-ripple {

    0%,
    100% {
      opacity: 0;
      transform: scale(0) translateZ(0);
    }
  }

  @keyframes nav-expand {

    0%,
    100% {
      opacity: 1;
      transform: scale(1) translateZ(0);
    }
  }
}

/* =========================
   桌面模式 (≥1190px)
========================= */
@media (min-width: 1190px) {
  .smart-nav-desktop {
    position: fixed;
    z-index: 99999;
    isolation: isolate;
    contain: layout style paint;
  }

  /* 按鈕基礎樣式 */
  .smart-nav-desktop-btn {
    position: absolute;
    width: var(--nav-desktop-btn);
    height: var(--nav-desktop-btn);
    border-radius: 50%;
    background: var(--nav-bg-light);
    border: 1.5px solid var(--nav-border);
    box-shadow: var(--nav-shadow),
      inset 0 1px 0 rgba(255, 255, 255, 0.9);
    display: flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    transition: all var(--nav-transition);
    animation: nav-float var(--nav-float-duration) ease-in-out infinite;
    cursor: pointer;
    padding: 0;
    will-change: transform, box-shadow;
    transform: translateZ(0);
    overflow: hidden;
  }

  /* 按鈕懸停效果 */
  .smart-nav-desktop-btn:hover {
    transform: scale(1.12) translateZ(0);
    box-shadow: 0 6px 25px rgba(139, 69, 19, 0.25),
      0 0 0 2px var(--nav-border-hover);
  }

  /* 按鈕點擊效果 */
  .smart-nav-desktop-btn:active {
    transform: scale(0.95) translateZ(0);
    border-color: var(--nav-border-active);
  }

  /* 按鈕位置 */
  .smart-nav-back {
    top: var(--nav-desktop-top);
    left: var(--nav-desktop-left);
    animation-delay: 0s;
    border-color: rgba(194, 59, 34, 0.3);
  }

  .smart-nav-section {
    top: calc(var(--nav-desktop-top) + 68px);
    left: var(--nav-desktop-left);
    animation-delay: 0.2s;
    border-color: rgba(92, 64, 55, 0.3);
  }

  .smart-nav-home {
    bottom: var(--nav-desktop-bottom);
    left: var(--nav-desktop-left);
    animation-delay: 0.4s;
    border-color: rgba(44, 36, 22, 0.3);
  }

  .smart-nav-top {
    bottom: var(--nav-desktop-bottom);
    right: var(--nav-desktop-right);
    animation-delay: 0.6s;
    border-color: rgba(139, 69, 19, 0.3);
  }

  /* 圖標樣式 */
  .smart-nav-icon {
    width: var(--nav-desktop-icon);
    height: var(--nav-desktop-icon);
    stroke-width: 2.3;
    stroke-linecap: round;
    stroke-linejoin: round;
    fill: none;
    transition: all 0.3s ease;
    will-change: stroke-width;
    pointer-events: none;
  }

  /* 按鈕懸停時的圖標效果 */
  .smart-nav-desktop-btn:hover .smart-nav-icon {
    stroke-width: 2.6;
  }

  /* 各按鈕圖標顏色 */
  .smart-nav-back .smart-nav-icon {
    stroke: var(--nav-color-back);
  }

  .smart-nav-section .smart-nav-icon {
    stroke: var(--nav-color-section);
  }

  .smart-nav-home .smart-nav-icon {
    stroke: var(--nav-color-home);
  }

  .smart-nav-top .smart-nav-icon {
    stroke: var(--nav-color-top);
  }

  /* 標籤樣式 */
  .smart-nav-label {
    position: absolute;
    left: calc(var(--nav-desktop-btn) + var(--nav-desktop-label-offset));
    background: rgba(0, 0, 0, 0.85);
    color: #fff;
    padding: 6px 12px;
    border-radius: 6px;
    font-size: 0.8rem;
    line-height: 1.2;
    white-space: nowrap;
    opacity: 0;
    transition: all var(--nav-transition);
    pointer-events: none;
    font-family: 'Noto Serif TC', serif;
    font-weight: 500;
    z-index: 100000;
    transform: translateX(-5px);
    will-change: opacity, transform;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
    backdrop-filter: blur(4px);
  }

  /* 懸停顯示標籤 */
  .smart-nav-desktop-btn:hover .smart-nav-label {
    opacity: 1;
    transform: translateX(0);
  }
}

/* 桌面深色模式 */
@media (min-width: 1190px) and (prefers-color-scheme: dark) {
  .smart-nav-desktop-btn {
    background: var(--nav-bg-dark);
    border-color: rgba(249, 168, 37, 0.25);
  }

  .smart-nav-label {
    background: rgba(0, 0, 0, 0.9);
    color: #f0f0f0;
  }
}

/* 桌面減少動畫 */
@media (min-width: 1190px) and (prefers-reduced-motion: reduce) {
  .smart-nav-desktop-btn {
    animation: none;
  }

  .smart-nav-desktop-btn:hover {
    transform: scale(1.05);
  }

  .smart-nav-label {
    transition: opacity 0.1s ease;
  }
}

/* =========================
   移動模式 (≤1189px)
========================= */
@media (max-width: 1189px) {
  .smart-nav-mobile {
    position: fixed;
    bottom: max(var(--nav-mobile-safe), env(safe-area-inset-bottom));
    right: max(var(--nav-mobile-safe), env(safe-area-inset-right));
    width: var(--nav-mobile-core);
    height: var(--nav-mobile-core);
    z-index: 99999;
    isolation: isolate;
    contain: layout style paint;
  }

  /* 核心按鈕 */
  .smart-nav-core {
    position: absolute;
    width: 100%;
    height: 100%;
    border-radius: 50%;
    background: var(--nav-bg-light);
    border: 2px solid var(--nav-border);
    box-shadow: var(--nav-shadow);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all var(--nav-transition);
    will-change: transform, box-shadow;
    transform: translateZ(0);
    overflow: hidden;
  }

  /* 核心按鈕狀態 */
  .smart-nav-core:hover,
  .smart-nav-core.expanded {
    border-color: var(--nav-color-accent);
    box-shadow: 0 0 0 1px var(--nav-border-hover),
      0 8px 32px rgba(249, 168, 37, 0.2);
  }

  /* 核心圖標 */
  .smart-nav-core-icon {
    width: 22px;
    height: 22px;
    stroke: var(--nav-color-primary);
    stroke-width: 2;
    stroke-linecap: round;
    stroke-linejoin: round;
    fill: none;
    transition: all var(--nav-transition);
    will-change: transform;
    pointer-events: none;
  }

  /* 展開時的核心圖標 */
  .smart-nav-core.expanded .smart-nav-core-icon {
    transform: rotate(45deg);
    stroke: var(--nav-color-accent);
  }

  /* 子按鈕基礎樣式 */
  .smart-nav-item {
    position: absolute;
    width: var(--nav-mobile-item);
    height: var(--nav-mobile-item);
    border-radius: 50%;
    background: var(--nav-bg-light);
    border: 1.5px solid var(--nav-border);
    box-shadow: var(--nav-shadow);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    opacity: 0;
    transform: scale(0) translateZ(0);
    transition: all var(--nav-transition);
    will-change: transform, opacity;
    overflow: hidden;
  }

  /* 子按鈕懸停效果 */
  .smart-nav-item:hover {
    border-color: var(--nav-color-accent);
    box-shadow: 0 0 0 2px var(--nav-border-hover);
  }

  /* 各子按鈕邊框顏色 */
  .smart-nav-back {
    border-color: rgba(194, 59, 34, 0.4);
  }

  .smart-nav-section {
    border-color: rgba(92, 64, 55, 0.4);
  }

  .smart-nav-home {
    border-color: rgba(44, 36, 22, 0.4);
  }

  .smart-nav-top {
    border-color: rgba(139, 69, 19, 0.4);
  }

  /* 展開狀態 */
  .smart-nav-mobile.expanded .smart-nav-item {
    opacity: 1;
    transform: scale(1) translateZ(0);
    animation: nav-expand var(--nav-animation-duration) ease-out;
  }

  /* 四個按鈕的展開佈局 */
  .smart-nav-mobile.expanded .smart-nav-back {
    transform: scale(1) translate(calc(-1 * var(--nav-mobile-offset)), 0) translateZ(0) !important;
    animation-delay: 0.1s;
  }

  .smart-nav-mobile.expanded .smart-nav-section {
    transform: scale(1) translate(0, calc(-1 * var(--nav-mobile-offset))) translateZ(0) !important;
    animation-delay: 0.2s;
  }

  .smart-nav-mobile.expanded .smart-nav-home {
    transform: scale(1) translate(var(--nav-mobile-offset), 0) translateZ(0) !important;
    animation-delay: 0.3s;
  }

  .smart-nav-mobile.expanded .smart-nav-top {
    transform: scale(1) translate(0, var(--nav-mobile-offset)) translateZ(0) !important;
    animation-delay: 0.4s;
  }

  /* 子按鈕圖標 */
  .smart-nav-item-icon {
    width: 20px;
    height: 20px;
    stroke-width: 2;
    stroke-linecap: round;
    stroke-linejoin: round;
    fill: none;
    will-change: stroke;
    pointer-events: none;
  }

  /* 各子按鈕圖標顏色 */
  .smart-nav-back .smart-nav-item-icon {
    stroke: var(--nav-color-back);
  }

  .smart-nav-section .smart-nav-item-icon {
    stroke: var(--nav-color-section);
  }

  .smart-nav-home .smart-nav-item-icon {
    stroke: var(--nav-color-home);
  }

  .smart-nav-top .smart-nav-item-icon {
    stroke: var(--nav-color-top);
  }

  /* 子按鈕標籤 */
  .smart-nav-item-label {
    position: absolute;
    bottom: calc(-1 * var(--nav-mobile-label-offset));
    background: rgba(0, 0, 0, 0.85);
    color: #fff;
    padding: 4px 10px;
    border-radius: 5px;
    font-size: 0.7rem;
    line-height: 1.2;
    white-space: nowrap;
    opacity: 0;
    transition: opacity var(--nav-transition);
    pointer-events: none;
    font-family: 'Noto Serif TC', serif;
    font-weight: 500;
    will-change: opacity;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.2);
    backdrop-filter: blur(4px);
  }

  /* 懸停顯示標籤 */
  .smart-nav-item:hover .smart-nav-item-label {
    opacity: 1;
  }
}

/* 移動端觸控設備優化 */
@media (max-width: 1189px) and (hover: none) and (pointer: coarse) {

  .smart-nav-core:hover,
  .smart-nav-item:hover {
    border-color: var(--nav-border);
    box-shadow: var(--nav-shadow);
  }

  .smart-nav-core:active,
  .smart-nav-item:active {
    border-color: var(--nav-color-accent);
    box-shadow: 0 0 0 2px var(--nav-border-hover);
    transform: scale(0.95) translateZ(0);
  }

  .smart-nav-item:hover .smart-nav-item-label {
    opacity: 0;
  }

  .smart-nav-item:active .smart-nav-item-label {
    opacity: 1;
  }
}

/* =========================
   斷點微調
========================= */

/* Tablet 微調 (≤1189px) — 已合併至上方 Tablet 區段 */
@media (max-width: 1189px) {
  :root {
    --nav-shadow: 0 4px 15px rgba(139, 69, 19, 0.12);
    --nav-desktop-btn: 52px;
    --nav-desktop-icon: 24px;
    --nav-mobile-core: 62px;
    --nav-mobile-item: 44px;
    --nav-mobile-offset: 65px;
    --nav-mobile-label-offset: 26px;
    --nav-mobile-safe: 15px;
    --nav-float-duration: 6s;
  }

  .smart-nav-mobile {
    bottom: max(var(--nav-mobile-safe), env(safe-area-inset-bottom));
    right: max(var(--nav-mobile-safe), env(safe-area-inset-right));
  }
}

/* 手機 (≤575px) */
@media (max-width: 575px) {
  :root {
    --nav-desktop-btn: 48px;
    --nav-desktop-icon: 22px;
    --nav-mobile-core: 58px;
    --nav-mobile-item: 40px;
    --nav-mobile-offset: 55px;
    --nav-mobile-label-offset: 24px;
    --nav-mobile-safe: 10px;
    --nav-desktop-label-offset: 5px;
  }

  .smart-nav-mobile {
    bottom: max(var(--nav-mobile-safe), env(safe-area-inset-bottom));
    right: max(var(--nav-mobile-safe), env(safe-area-inset-right));
  }

  .smart-nav-item-icon {
    width: 18px;
    height: 18px;
  }

  .smart-nav-label {
    font-size: 0.7rem;
    padding: 4px 8px;
  }

  .smart-nav-item-label {
    font-size: 0.65rem;
    padding: 3px 8px;
  }
}

/* 大螢幕 (≥1600px) */
@media (min-width: 1600px) {
  :root {
    --nav-desktop-btn: 64px;
    --nav-desktop-icon: 32px;
    --nav-desktop-left: max(25px, env(safe-area-inset-left));
    --nav-desktop-right: max(25px, env(safe-area-inset-right));
  }

  .smart-nav-back,
  .smart-nav-section,
  .smart-nav-home {
    left: var(--nav-desktop-left);
  }

  .smart-nav-top {
    right: var(--nav-desktop-right);
  }
}

/* =========================
   深色模式
========================= */
@media (prefers-color-scheme: dark) {

  .smart-nav-core,
  .smart-nav-item {
    background: var(--nav-bg-dark);
    border-color: rgba(249, 168, 37, 0.25);
  }

  .smart-nav-label,
  .smart-nav-item-label {
    background: rgba(30, 30, 30, 0.95);
    color: #f0f0f0;
  }
}

/* =========================
   顯示/隱藏邏輯
========================= */
/* 在移動端隱藏桌面模式 */
@media (max-width: 1189px) {
  .smart-nav-desktop {
    display: none !important;
  }
}

/* 在桌面端隱藏移動模式 */
@media (min-width: 1190px) {
  .smart-nav-mobile {
    display: none !important;
  }
}

/* =========================
   輔助類別
========================= */
/* 隱藏類 */
.smart-nav-hidden {
  display: none !important;
  visibility: hidden !important;
  opacity: 0 !important;
  pointer-events: none !important;
}

/* 無動畫類 */
.smart-nav-no-animation * {
  animation: none !important;
  transition: none !important;
}

/* 高對比模式支持 */
@media (prefers-contrast: high) {

  .smart-nav-desktop-btn,
  .smart-nav-core,
  .smart-nav-item {
    border-width: 2px;
    border-style: solid;
  }

  .smart-nav-label,
  .smart-nav-item-label {
    background: #000;
    color: #fff;
    border: 1px solid #fff;
  }
}