/* ================================
   时光胶片 - 六周年纪念网页重设计
   Design Concept: Vintage Film Aesthetic
   ================================ */

/* Google Fonts Import - 优雅的衬线字体 + 手写风格 */
@import url('https://fonts.googleapis.com/css2?family=Crimson+Pro:wght@300;400;600;700&family=Lora:ital,wght@0,400;0,600;1,400&family=Caveat:wght@400;600&display=swap');

:root {
  /* 复古胶片配色 - 温暖的模拟色调 */
  --film-cream: #FFF8E8;
  --film-sepia: #E8D5B7;
  --film-amber: #D4A574;
  --film-gold: #B8860B;
  --film-brown: #8B7355;
  --film-dark: #3E2723;

  /* 强调色 - 柔和的琥珀和玫瑰金 */
  --accent-amber: #FFB84D;
  --accent-rose: #D4A5A5;
  --accent-sage: #A8B8A0;

  /* 纸张质感 */
  --paper-white: #FFFEF9;
  --paper-aged: #F5E6D3;

  /* 字体 */
  --font-display: 'Crimson Pro', serif;
  --font-body: 'Lora', serif;
  --font-handwrite: 'Caveat', cursive;

  /* 间距 */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 2rem;
  --spacing-lg: 4rem;
  --spacing-xl: 6rem;

  /* 阴影 - 柔和的胶片风格阴影 */
  --shadow-soft: 0 4px 20px rgba(62, 39, 35, 0.08);
  --shadow-medium: 0 8px 30px rgba(62, 39, 35, 0.12);
  --shadow-strong: 0 12px 40px rgba(62, 39, 35, 0.18);
}

/* ================================
   全局重置与基础样式
   ================================ */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  overflow-x: hidden;
}

body {
  font-family: var(--font-body);
  /* 金色麦田笔触 - 梵高干草堆风格 */
  background:
    /* 厚重油彩层 - 最上层高光 */
    radial-gradient(ellipse 80% 50% at 30% 20%, rgba(255, 223, 128, 0.35) 0%, transparent 50%),
    radial-gradient(ellipse 60% 40% at 70% 80%, rgba(255, 184, 77, 0.25) 0%, transparent 50%),
    radial-gradient(ellipse 50% 35% at 85% 30%, rgba(212, 165, 116, 0.2) 0%, transparent 45%),
    /* 笔触纹理层 */
    repeating-linear-gradient(
      -45deg,
      transparent 0px,
      transparent 2px,
      rgba(184, 134, 11, 0.06) 2px,
      rgba(184, 134, 11, 0.06) 4px
    ),
    repeating-linear-gradient(
      45deg,
      transparent 0px,
      transparent 3px,
      rgba(139, 90, 43, 0.04) 3px,
      rgba(139, 90, 43, 0.04) 6px
    ),
    /* 基础渐变 - 模拟干草堆色调 */
    linear-gradient(
      160deg,
      #F7E8C8 0%,
      #E8D5A8 15%,
      #D4B896 30%,
      #C9A87C 50%,
      #BF9B6A 70%,
      #A8845A 85%,
      #8B6B4A 100%
    );
  color: var(--film-dark);
  line-height: 1.7;
  overflow-x: hidden;
  position: relative;
}

/* 油画笔触纹理层 */
body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 500 500' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='brush'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.04' numOctaves='5' seed='15' stitchTiles='stitch'/%3E%3CfeDisplacementMap in='SourceGraphic' scale='8'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23brush)' fill='%23D4A574' opacity='0.15'/%3E%3C/svg%3E");
  pointer-events: none;
  z-index: 1;
  opacity: 0.7;
  mix-blend-mode: overlay;
}

/* 油画颗粒质感 */
body::after {
  content: '';
  position: fixed;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='grain'%3E%3CfeTurbulence type='turbulence' baseFrequency='0.7' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23grain)' opacity='0.06'/%3E%3C/svg%3E");
  pointer-events: none;
  z-index: 2;
  animation: grain 10s steps(8) infinite;
  opacity: 0.5;
}

@keyframes grain {
  0%, 100% { transform: translate(0, 0); }
  10% { transform: translate(-3%, -8%); }
  20% { transform: translate(-10%, 3%); }
  30% { transform: translate(5%, -15%); }
  40% { transform: translate(-3%, 18%); }
  50% { transform: translate(-10%, 8%); }
  60% { transform: translate(10%, 0%); }
  70% { transform: translate(0%, 10%); }
  80% { transform: translate(2%, 20%); }
  90% { transform: translate(-8%, 5%); }
}

/* ================================
   密码保护页面
   ================================ */
.password-screen {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, var(--film-cream) 0%, var(--film-sepia) 100%);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 10000;
  transition: opacity 0.6s ease, visibility 0.6s ease;
}

.password-screen.hidden {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

.password-container {
  background: linear-gradient(135deg, var(--paper-white) 0%, var(--paper-aged) 100%);
  padding: 3rem 2.5rem;
  border-radius: 12px;
  box-shadow: var(--shadow-strong);
  border: 2px solid var(--film-gold);
  text-align: center;
  max-width: 380px;
  width: 90%;
  animation: modalSlideIn 0.6s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.password-container h2 {
  font-family: var(--font-display);
  font-size: 2rem;
  color: var(--film-gold);
  margin-bottom: 0.5rem;
  font-weight: 700;
}

.password-container > p {
  font-family: var(--font-body);
  color: var(--film-brown);
  margin-bottom: 1.5rem;
  font-size: 1rem;
}

.password-container input {
  width: 100%;
  padding: 14px 18px;
  font-family: var(--font-body);
  font-size: 1.1rem;
  border: 2px solid var(--film-amber);
  border-radius: 8px;
  background: var(--paper-white);
  color: var(--film-dark);
  text-align: center;
  letter-spacing: 0.15em;
  transition: all 0.3s ease;
  margin-bottom: 1rem;
}

.password-container input:focus {
  outline: none;
  border-color: var(--film-gold);
  box-shadow: 0 0 0 3px rgba(184, 134, 11, 0.2);
}

.password-container input::placeholder {
  color: var(--film-brown);
  opacity: 0.5;
  letter-spacing: 0.05em;
}

.password-container button {
  width: 100%;
  padding: 14px 32px;
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 600;
  background: linear-gradient(135deg, var(--film-gold) 0%, var(--accent-amber) 100%);
  color: var(--paper-white);
  border: none;
  border-radius: 50px;
  cursor: pointer;
  box-shadow: var(--shadow-medium);
  transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.2);
}

.password-container button:hover {
  transform: translateY(-2px) scale(1.02);
  box-shadow: var(--shadow-strong);
}

.password-container button:active {
  transform: translateY(0) scale(1);
}

.password-error {
  color: #c0392b;
  font-family: var(--font-body);
  font-size: 0.95rem;
  margin-top: 1rem;
  min-height: 1.2em;
  opacity: 0;
  transition: opacity 0.3s ease;
}

.password-error.show {
  opacity: 1;
}

.password-hint {
  font-family: var(--font-handwrite);
  color: var(--film-brown);
  font-size: 1rem;
  margin-top: 1.5rem !important;
  margin-bottom: 0 !important;
  opacity: 0.7;
}

@keyframes shake {
  0%, 100% { transform: translateX(0); }
  10%, 30%, 50%, 70%, 90% { transform: translateX(-8px); }
  20%, 40%, 60%, 80% { transform: translateX(8px); }
}

/* ================================
   Loading 动画 - 胶片卷轴风格
   ================================ */
.loading {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, var(--film-cream) 0%, var(--film-sepia) 100%);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  z-index: 9999;
  transition: opacity 0.8s ease-out, visibility 0.8s ease-out;
}

.loading.hidden {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

.loading-spinner {
  width: 80px;
  height: 80px;
  position: relative;
  animation: rotate 2s linear infinite;
}

.loading-spinner::before,
.loading-spinner::after {
  content: '';
  position: absolute;
  width: 100%;
  height: 100%;
  border: 3px solid transparent;
  border-top-color: var(--film-gold);
  border-radius: 50%;
}

.loading-spinner::before {
  animation: rotate 1.5s linear infinite;
}

.loading-spinner::after {
  border-top-color: var(--accent-amber);
  animation: rotate 2.5s linear infinite reverse;
}

@keyframes rotate {
  to { transform: rotate(360deg); }
}

.loading p {
  margin-top: var(--spacing-md);
  font-family: var(--font-display);
  font-size: 1.2rem;
  color: var(--film-brown);
  letter-spacing: 0.1em;
  animation: pulse-text 2s ease-in-out infinite;
}

@keyframes pulse-text {
  0%, 100% { opacity: 0.6; }
  50% { opacity: 1; }
}

/* ================================
   背景音乐控制 - 复古收音机风格
   ================================ */
.music-control {
  position: fixed;
  top: 30px;
  right: 30px;
  z-index: 1000;
}

.music-btn {
  width: 60px;
  height: 60px;
  border-radius: 50%;
  border: 3px solid var(--film-gold);
  background: linear-gradient(135deg, var(--paper-white) 0%, var(--film-sepia) 100%);
  box-shadow: var(--shadow-medium), inset 0 2px 10px rgba(255, 255, 255, 0.5);
  cursor: pointer;
  font-size: 26px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
  position: relative;
  overflow: hidden;
}

.music-btn::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 0;
  height: 0;
  border-radius: 50%;
  background: radial-gradient(circle, var(--accent-amber) 0%, transparent 70%);
  transform: translate(-50%, -50%);
  transition: width 0.6s ease, height 0.6s ease;
  opacity: 0;
}

.music-btn:hover {
  transform: scale(1.1) rotate(5deg);
  box-shadow: var(--shadow-strong), inset 0 2px 15px rgba(255, 255, 255, 0.7);
}

.music-btn.playing::before {
  width: 200%;
  height: 200%;
  opacity: 0.2;
  animation: ripple 2s ease-out infinite;
}

@keyframes ripple {
  0% { transform: translate(-50%, -50%) scale(0); opacity: 0.4; }
  100% { transform: translate(-50%, -50%) scale(1); opacity: 0; }
}

.music-icon {
  position: relative;
  z-index: 1;
  animation: music-note 3s ease-in-out infinite;
}

@keyframes music-note {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-3px); }
}

/* ================================
   主容器 - 胶片卷轴布局
   ================================ */
.book-container {
  position: relative;
  width: 100%;
  min-height: 100vh;
  z-index: 3;
}

/* ================================
   页面基础样式 - 胶片帧风格
   ================================ */
.page {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transform: translateY(40px) scale(0.95);
  transition:
    opacity 0.8s cubic-bezier(0.4, 0, 0.2, 1),
    transform 0.8s cubic-bezier(0.4, 0, 0.2, 1),
    visibility 0.8s;
  padding: var(--spacing-md);
}

.page.active {
  opacity: 1;
  visibility: visible;
  position: relative;
  transform: translateY(0) scale(1);
}

/* 胶片边框装饰 */
.page::before {
  content: '';
  position: absolute;
  top: 20px;
  left: 20px;
  right: 20px;
  bottom: 20px;
  border: 2px solid var(--film-amber);
  border-radius: 4px;
  opacity: 0.3;
  pointer-events: none;
}

/* ================================
   纯文字页面 - 手写信件风格
   ================================ */
.text-only-page {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  padding: var(--spacing-lg) var(--spacing-md);
  width: 100%;
}

.text-only-page .text-content {
  max-width: 700px;
  padding: var(--spacing-xl) var(--spacing-lg);
  background:
    linear-gradient(135deg, var(--paper-white) 0%, var(--paper-aged) 100%);
  border-radius: 8px;
  box-shadow:
    var(--shadow-strong),
    inset 0 1px 0 rgba(255, 255, 255, 0.8);
  position: relative;
  border: 1px solid rgba(184, 134, 11, 0.2);
}

/* 纸张折痕效果 */
.text-only-page .text-content::before {
  content: '';
  position: absolute;
  top: 0;
  left: 30%;
  width: 1px;
  height: 100%;
  background: linear-gradient(to bottom,
    transparent 0%,
    rgba(139, 115, 85, 0.1) 20%,
    rgba(139, 115, 85, 0.15) 50%,
    rgba(139, 115, 85, 0.1) 80%,
    transparent 100%
  );
}

/* 邮票装饰 */
.text-only-page .text-content::after {
  content: '';
  position: absolute;
  top: 30px;
  right: 30px;
  width: 60px;
  height: 80px;
  background: linear-gradient(135deg, var(--accent-rose) 0%, var(--film-amber) 100%);
  border: 3px dashed var(--film-brown);
  opacity: 0.15;
  border-radius: 2px;
}

.text-content h1 {
  font-family: var(--font-display);
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 700;
  color: var(--film-gold);
  margin-bottom: var(--spacing-lg);
  line-height: 1.2;
  position: relative;
  display: inline-block;
  text-shadow: 2px 2px 4px rgba(62, 39, 35, 0.1);
}

/* 手写下划线效果 */
.text-content h1::after {
  content: '';
  position: absolute;
  bottom: -10px;
  left: 0;
  width: 100%;
  height: 3px;
  background: linear-gradient(to right,
    var(--accent-amber) 0%,
    var(--accent-amber) 60%,
    transparent 100%
  );
  transform: skewY(-1deg);
  opacity: 0.6;
}

.text-content p {
  font-family: var(--font-body);
  font-size: clamp(1.1rem, 2.5vw, 1.3rem);
  line-height: 2;
  color: var(--film-dark);
  margin-bottom: var(--spacing-md);
  text-indent: 2em;
  position: relative;
}

.text-content p:first-of-type {
  margin-top: var(--spacing-md);
}

/* 手写批注风格 */
.text-content .large-text {
  font-family: var(--font-handwrite);
  font-size: clamp(1.5rem, 3vw, 2rem);
  color: var(--film-gold);
  font-weight: 600;
  text-indent: 0;
  margin: var(--spacing-lg) 0;
  padding-left: var(--spacing-md);
  border-left: 4px solid var(--accent-amber);
  line-height: 1.6;
}

.text-content .signature {
  font-family: var(--font-handwrite);
  font-size: clamp(1.3rem, 2.5vw, 1.6rem);
  color: var(--film-brown);
  text-align: right;
  margin-top: var(--spacing-lg);
  text-indent: 0;
  font-weight: 600;
}

/* ================================
   按钮样式 - 复古胶片按钮
   ================================ */
.start-btn,
.restart-btn {
  margin-top: var(--spacing-lg);
  padding: 16px 40px;
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  background: linear-gradient(135deg, var(--film-gold) 0%, var(--accent-amber) 100%);
  color: var(--paper-white);
  border: none;
  border-radius: 50px;
  cursor: pointer;
  box-shadow:
    var(--shadow-medium),
    inset 0 1px 0 rgba(255, 255, 255, 0.3);
  transition: all 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
  position: relative;
  overflow: hidden;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.2);
}

.start-btn::before,
.restart-btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg,
    transparent 0%,
    rgba(255, 255, 255, 0.3) 50%,
    transparent 100%
  );
  transition: left 0.6s ease;
}

.start-btn:hover,
.restart-btn:hover {
  transform: translateY(-3px) scale(1.05);
  box-shadow:
    var(--shadow-strong),
    inset 0 1px 0 rgba(255, 255, 255, 0.4);
}

.start-btn:hover::before,
.restart-btn:hover::before {
  left: 100%;
}

.start-btn:active,
.restart-btn:active {
  transform: translateY(-1px) scale(1.02);
}

/* ================================
   照片页面 - 胶片相框风格
   ================================ */
.photo-page {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: var(--spacing-xl);
  align-items: center;
  justify-content: center;
  max-width: 1400px;
  margin: 0 auto;
  padding: var(--spacing-lg) var(--spacing-md);
}

.photo-text {
  padding: var(--spacing-lg);
  position: relative;
  animation: slideInLeft 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

@keyframes slideInLeft {
  from {
    opacity: 0;
    transform: translateX(-40px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

.photo-text .part-title {
  font-family: var(--font-display);
  font-size: 0.9rem;
  color: var(--film-brown);
  text-transform: uppercase;
  letter-spacing: 0.2em;
  margin-bottom: var(--spacing-sm);
  opacity: 0.7;
  font-weight: 600;
}

.photo-text .sentence {
  font-family: var(--font-body);
  font-size: clamp(1.4rem, 3vw, 2rem);
  line-height: 1.8;
  color: var(--film-dark);
  font-weight: 400;
  position: relative;
  padding-left: var(--spacing-md);
}

/* 引号装饰 */
.photo-text .sentence::before {
  content: '"';
  position: absolute;
  left: -10px;
  top: -20px;
  font-family: var(--font-display);
  font-size: 5rem;
  color: var(--film-amber);
  opacity: 0.3;
  line-height: 1;
}

/* ================================
   照片容器 - 拍立得相片效果
   ================================ */
.photo-container {
  position: relative;
  padding: 20px 20px 60px 20px; /* 底部更宽，模拟拍立得 */
  background: linear-gradient(to bottom,
    var(--paper-white) 0%,
    var(--paper-white) 95%,
    #F8F4EE 100%
  );
  box-shadow:
    0 10px 40px rgba(62, 39, 35, 0.15),
    0 2px 8px rgba(62, 39, 35, 0.1);
  border-radius: 2px;
  animation: slideInRight 0.8s cubic-bezier(0.4, 0, 0.2, 1);
  transform-origin: center center;
  transition: all 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

/* 每张照片随机倾斜角度（通过 nth-child 实现） */
.photo-container:nth-child(odd) {
  transform: rotate(-1.5deg);
}

.photo-container:nth-child(even) {
  transform: rotate(1.2deg);
}

.photo-container:nth-child(3n) {
  transform: rotate(-0.8deg);
}

.photo-container:nth-child(5n) {
  transform: rotate(2deg);
}

@keyframes slideInRight {
  from {
    opacity: 0;
    transform: translateX(40px) rotate(3deg);
  }
  to {
    opacity: 1;
  }
}

/* 拍立得照片底部手写区域 */
.photo-container::after {
  content: attr(data-caption);
  position: absolute;
  bottom: 12px;
  left: 20px;
  right: 20px;
  font-family: var(--font-handwrite);
  font-size: 1rem;
  color: rgba(62, 39, 35, 0.6);
  text-align: center;
  letter-spacing: 0.05em;
  pointer-events: none;
}

.photo-container img {
  width: 100%;
  height: auto;
  display: block;
  border-radius: 0;
  transition: transform 0.4s ease;
  filter: sepia(10%) brightness(1.02) contrast(1.05) saturate(0.95);
  box-shadow: inset 0 0 20px rgba(0, 0, 0, 0.05);
}

/* 悬停效果 - 轻微抬起 */
.photo-container:hover {
  transform: translateY(-8px) rotate(0deg) !important;
  box-shadow:
    0 20px 60px rgba(62, 39, 35, 0.25),
    0 5px 15px rgba(62, 39, 35, 0.15);
}

.photo-container:hover img {
  filter: sepia(5%) brightness(1.05) contrast(1.08) saturate(1);
}

/* 拍立得胶带粘贴效果（可选装饰） */
.photo-container::before {
  content: '';
  position: absolute;
  top: -8px;
  left: 50%;
  transform: translateX(-50%);
  width: 80px;
  height: 25px;
  background: rgba(255, 248, 232, 0.7);
  border-left: 1px solid rgba(212, 165, 116, 0.3);
  border-right: 1px solid rgba(212, 165, 116, 0.3);
  box-shadow:
    0 1px 3px rgba(0, 0, 0, 0.1),
    inset 0 0 10px rgba(255, 255, 255, 0.5);
  opacity: 0.8;
  pointer-events: none;
}

/* ================================
   视频背景页面
   ================================ */
.video-background {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;
  z-index: 1;
}

.video-background video {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: sepia(15%) brightness(0.9) contrast(1.1);
}

/* 视频复古光晕效果 */
.video-background::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: radial-gradient(
    ellipse at center,
    transparent 0%,
    rgba(232, 213, 183, 0.3) 100%
  );
  pointer-events: none;
}

.video-overlay {
  position: absolute;
  bottom: 60px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 2;
}

/* ================================
   导航控制 - 胶片卷轴控制器
   ================================ */
.controls {
  position: fixed;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  z-index: 100;
  background:
    linear-gradient(135deg, rgba(255, 255, 255, 0.95) 0%, rgba(245, 230, 211, 0.95) 100%);
  backdrop-filter: blur(10px);
  padding: 16px 32px;
  border-radius: 60px;
  box-shadow: var(--shadow-strong);
  border: 2px solid rgba(184, 134, 11, 0.2);
}

.nav-btn {
  width: 50px;
  height: 50px;
  border-radius: 50%;
  border: 2px solid var(--film-gold);
  background: linear-gradient(135deg, var(--paper-white) 0%, var(--film-sepia) 100%);
  cursor: pointer;
  font-size: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
  color: var(--film-gold);
  box-shadow: var(--shadow-soft);
}

.nav-btn:hover:not(:disabled) {
  background: linear-gradient(135deg, var(--film-gold) 0%, var(--accent-amber) 100%);
  color: var(--paper-white);
  transform: scale(1.15);
  box-shadow: var(--shadow-medium);
}

.nav-btn:disabled {
  opacity: 0.3;
  cursor: not-allowed;
  border-color: var(--film-brown);
}

.page-indicator {
  font-family: var(--font-display);
  font-size: 1.1rem;
  color: var(--film-dark);
  font-weight: 600;
  min-width: 90px;
  text-align: center;
  letter-spacing: 0.05em;
}

/* ================================
   互动问题弹窗 - 复古信封风格
   ================================ */
.modal {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(62, 39, 35, 0.7);
  backdrop-filter: blur(8px);
  z-index: 2000;
  align-items: center;
  justify-content: center;
  animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.modal.show {
  display: flex;
}

.modal-content {
  background: linear-gradient(135deg, var(--paper-white) 0%, var(--paper-aged) 100%);
  padding: var(--spacing-xl) var(--spacing-lg);
  border-radius: 12px;
  max-width: 600px;
  width: 90%;
  box-shadow: var(--shadow-strong);
  border: 3px solid var(--film-gold);
  position: relative;
  animation: modalSlideIn 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

@keyframes modalSlideIn {
  from {
    opacity: 0;
    transform: translateY(-50px) scale(0.9);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

/* 信封邮戳装饰 */
.modal-content::before {
  content: '';
  position: absolute;
  top: 20px;
  right: 20px;
  width: 80px;
  height: 80px;
  border: 3px solid var(--film-brown);
  border-radius: 50%;
  opacity: 0.2;
}

.modal-content h3 {
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 3vw, 2rem);
  color: var(--film-gold);
  margin-bottom: var(--spacing-lg);
  text-align: center;
  font-weight: 700;
}

.question-options {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

.question-options button {
  padding: 16px 24px;
  font-family: var(--font-body);
  font-size: 1.1rem;
  background: var(--paper-white);
  border: 2px solid var(--film-amber);
  border-radius: 8px;
  cursor: pointer;
  transition: all 0.3s ease;
  color: var(--film-dark);
  text-align: left;
  position: relative;
  overflow: hidden;
}

.question-options button::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent 0%, var(--film-sepia) 50%, transparent 100%);
  transition: left 0.5s ease;
}

.question-options button:hover {
  background: var(--film-sepia);
  border-color: var(--film-gold);
  transform: translateX(8px);
  box-shadow: var(--shadow-soft);
}

.question-options button:hover::before {
  left: 100%;
}

.question-feedback {
  text-align: center;
  margin-top: var(--spacing-md);
  animation: fadeIn 0.5s ease;
}

.question-feedback p {
  font-family: var(--font-handwrite);
  font-size: 1.4rem;
  color: var(--accent-amber);
  margin-bottom: var(--spacing-md);
  font-weight: 600;
}

.question-feedback button {
  padding: 12px 32px;
  font-family: var(--font-display);
  font-size: 1rem;
  background: linear-gradient(135deg, var(--film-gold) 0%, var(--accent-amber) 100%);
  color: var(--paper-white);
  border: none;
  border-radius: 30px;
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: var(--shadow-soft);
  font-weight: 600;
}

.question-feedback button:hover {
  transform: scale(1.08);
  box-shadow: var(--shadow-medium);
}

/* ================================
   渐现动画
   ================================ */
.fade-in {
  animation: fadeInUp 1s cubic-bezier(0.4, 0, 0.2, 1);
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ================================
   响应式设计 - 移动端优化
   ================================ */
@media (max-width: 768px) {
  :root {
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
  }

  .music-btn {
    width: 50px;
    height: 50px;
    font-size: 22px;
  }

  .music-control {
    top: 20px;
    right: 20px;
  }

  .text-only-page .text-content {
    padding: var(--spacing-lg) var(--spacing-md);
  }

  .text-content h1 {
    font-size: 2rem;
  }

  .text-content p {
    font-size: 1.1rem;
    text-indent: 1.5em;
  }

  /* 移动端照片页面改为上下布局 */
  .photo-page {
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
    padding: var(--spacing-md);
  }

  .photo-text {
    padding: var(--spacing-md);
    order: 2;
  }

  .photo-container {
    order: 1;
    padding: 15px 15px 50px 15px; /* 移动端拍立得底部间距 */
    transform: rotate(0deg) !important; /* 移动端不倾斜 */
  }

  /* 移动端拍立得底部文字 */
  .photo-container::after {
    font-size: 0.9rem;
    bottom: 10px;
  }

  .photo-text .sentence {
    font-size: 1.3rem;
    text-align: center;
    padding-left: 0;
  }

  .photo-text .sentence::before {
    display: none;
  }

  /* 移动端完全隐藏底部导航栏 */
  .controls {
    display: none !important;
  }

  .modal-content {
    padding: var(--spacing-lg) var(--spacing-md);
  }

  .start-btn,
  .restart-btn {
    padding: 14px 32px;
    font-size: 1rem;
  }
}

/* ================================
   特殊效果 - 光晕动画
   ================================ */
@keyframes glow {
  0%, 100% {
    box-shadow:
      0 0 20px rgba(255, 184, 77, 0.3),
      0 0 40px rgba(255, 184, 77, 0.2),
      0 0 60px rgba(255, 184, 77, 0.1);
  }
  50% {
    box-shadow:
      0 0 30px rgba(255, 184, 77, 0.4),
      0 0 60px rgba(255, 184, 77, 0.3),
      0 0 90px rgba(255, 184, 77, 0.2);
  }
}

/* 页面切换时的光晕效果 */
.page.active {
  animation: pageGlow 1.5s ease-out;
}

@keyframes pageGlow {
  0% {
    filter: brightness(1.2);
  }
  100% {
    filter: brightness(1);
  }
}

/* ================================
   移动端增强功能
   ================================ */

/* 触摸反馈效果 */
.tap-feedback {
  position: fixed;
  pointer-events: none;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(212, 165, 116, 0.4) 0%, transparent 70%);
  width: 100px;
  height: 100px;
  transform: translate(-50%, -50%) scale(0);
  opacity: 0;
  z-index: 999;
  transition: all 0.6s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.tap-feedback.active {
  transform: translate(-50%, -50%) scale(2);
  opacity: 1;
  animation: tapRipple 0.6s ease-out forwards;
}

@keyframes tapRipple {
  0% {
    transform: translate(-50%, -50%) scale(0);
    opacity: 1;
  }
  100% {
    transform: translate(-50%, -50%) scale(2);
    opacity: 0;
  }
}

/* 首次访问引导提示 */
.navigation-hint {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(62, 39, 35, 0.85);
  backdrop-filter: blur(8px);
  z-index: 9998;
  display: none;
  justify-content: center;
  align-items: center;
  animation: fadeIn 0.5s ease;
}

.navigation-hint.show {
  display: flex;
}

.hint-content {
  background: linear-gradient(135deg, var(--paper-white) 0%, var(--paper-aged) 100%);
  padding: 3rem 2rem;
  border-radius: 12px;
  text-align: center;
  max-width: 350px;
  margin: 0 20px;
  box-shadow: var(--shadow-strong);
  border: 2px solid var(--film-gold);
  animation: modalSlideIn 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.hint-content h3 {
  font-family: var(--font-display);
  color: var(--film-gold);
  margin-bottom: 1.5rem;
  font-size: 1.5rem;
  font-weight: 700;
}

.hint-content p {
  font-family: var(--font-body);
  color: var(--film-dark);
  line-height: 1.8;
  margin-bottom: 0.5rem;
  font-size: 1.1rem;
}

.hint-arrows {
  display: flex;
  justify-content: space-around;
  margin: 2rem 0;
  font-size: 3rem;
  color: var(--film-gold);
}

.hint-content button {
  padding: 12px 32px;
  font-family: var(--font-display);
  background: linear-gradient(135deg, var(--film-gold) 0%, var(--accent-amber) 100%);
  color: var(--paper-white);
  border: none;
  border-radius: 30px;
  cursor: pointer;
  font-size: 1rem;
  font-weight: 600;
  margin-top: 1rem;
  box-shadow: var(--shadow-soft);
  transition: all 0.3s ease;
}

.hint-content button:hover {
  transform: scale(1.05);
  box-shadow: var(--shadow-medium);
}

/* 移动端进度条 */
.mobile-progress {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: rgba(212, 165, 116, 0.2);
  z-index: 999;
}

.mobile-progress-bar {
  height: 100%;
  background: linear-gradient(90deg, var(--film-gold) 0%, var(--accent-amber) 100%);
  transition: width 0.6s cubic-bezier(0.4, 0, 0.2, 1);
  box-shadow: 0 0 10px rgba(255, 184, 77, 0.5);
  width: 0%;
}

@media (max-width: 768px) {
  .mobile-progress {
    display: block;
  }
}