@import url('https://fonts.googleapis.com/css2?family=Noto+Serif+SC:wght@400;700;900&display=swap');

:root {
    --bg-deep: #08080c;
    --bg-card: rgba(16, 14, 20, 0.92);
    --bg-overlay: rgba(10, 8, 14, 0.85);
    --red: #c0392b;
    --red-bright: #e8453c;
    --red-glow: #ff4444;
    --gold: #c9a96e;
    --gold-light: #e8d5a3;
    --gold-dark: #8b6914;
    --text: #e8e6e3;
    --text-dim: #9a9690;
    --text-muted: #6b6660;
    --border: rgba(201, 169, 110, 0.25);
    --border-glow: rgba(201, 169, 110, 0.5);
    --shadow-red: 0 0 30px rgba(200, 40, 30, 0.3);
    --shadow-gold: 0 0 20px rgba(201, 169, 110, 0.25);
    --radius: 12px;
    --radius-lg: 20px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Noto Serif SC', 'SimSun', 'STSong', serif;
    background: var(--bg-deep);
    color: var(--text);
    min-height: 100vh;
    overflow-x: hidden;
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
}

/* ===== 背景层 ===== */
.bg-layer {
    position: fixed;
    inset: 0;
    z-index: 0;
    pointer-events: none;
}
.bg-layer::before {
    content: '';
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse 80% 60% at 50% 0%, rgba(180, 40, 30, 0.08) 0%, transparent 60%),
        radial-gradient(ellipse 60% 50% at 80% 30%, rgba(201, 169, 110, 0.04) 0%, transparent 50%),
        radial-gradient(ellipse 50% 40% at 20% 70%, rgba(180, 40, 30, 0.05) 0%, transparent 50%);
}
.bg-particles {
    position: fixed;
    inset: 0;
    z-index: 0;
    pointer-events: none;
    opacity: 0.4;
}

/* ===== 导航栏 ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(8, 8, 12, 0.88);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(201, 169, 110, 0.12);
    transition: all 0.3s ease;
}
.navbar.scrolled {
    background: rgba(6, 5, 9, 0.95);
    border-bottom-color: rgba(201, 169, 110, 0.25);
    box-shadow: 0 4px 30px rgba(0,0,0,0.5);
}
.nav-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    height: 64px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}
.nav-logo {
    display: flex;
    align-items: center;
    gap: 12px;
    text-decoration: none;
    color: var(--gold-light);
    font-size: 1.3rem;
    font-weight: 900;
    letter-spacing: 3px;
}
.nav-logo img {
    width: 40px;
    height: 40px;
    border-radius: 8px;
    object-fit: cover;
}
.nav-links {
    display: flex;
    gap: 32px;
    list-style: none;
}
.nav-links a {
    color: var(--text-dim);
    text-decoration: none;
    font-size: 0.92rem;
    letter-spacing: 2px;
    transition: color 0.3s;
    position: relative;
}
.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 50%;
    transform: translateX(-50%) scaleX(0);
    width: 20px;
    height: 2px;
    background: var(--red-bright);
    transition: transform 0.3s ease;
}
.nav-links a:hover,
.nav-links a.active {
    color: var(--gold-light);
}
.nav-links a:hover::after,
.nav-links a.active::after {
    transform: translateX(-50%) scaleX(1);
}
.nav-cta {
    background: linear-gradient(135deg, var(--red), var(--red-bright));
    color: #fff !important;
    padding: 8px 22px !important;
    border-radius: 25px;
    font-weight: 700 !important;
    letter-spacing: 2px !important;
    font-size: 0.85rem !important;
    transition: all 0.3s ease !important;
    box-shadow: 0 4px 20px rgba(200, 40, 30, 0.4);
}
.nav-cta:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(200, 40, 30, 0.6);
}
.nav-cta::after { display: none !important; }

.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    background: none;
    border: none;
    padding: 8px;
}
.menu-toggle span {
    display: block;
    width: 26px;
    height: 2px;
    background: var(--gold-light);
    transition: all 0.3s ease;
    border-radius: 2px;
}
.menu-toggle.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.menu-toggle.active span:nth-child(2) { opacity: 0; }
.menu-toggle.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

/* ===== Hero区域 ===== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 120px 24px 80px;
    z-index: 1;
}
.hero-bg {
    position: absolute;
    inset: 0;
    z-index: -1;
    background-image: url('images/banner/banner4a2b840cd896184e4c5020756d0e16421784108260.jpg');
    background-size: cover;
    background-position: center top;
    background-repeat: no-repeat;
}
.hero-bg::before {
    content: '';
    position: absolute;
    inset: 0;
    background: rgba(6, 4, 10, 0.7);
    z-index: 1;
}
.hero-bg::after {
    content: '';
    position: absolute;
    inset: 0;
    z-index: 2;
    background:
        radial-gradient(circle at 50% 30%, rgba(200, 40, 30, 0.15) 0%, transparent 50%),
        radial-gradient(circle at 30% 60%, rgba(201, 169, 110, 0.06) 0%, transparent 40%),
        radial-gradient(circle at 70% 50%, rgba(160, 30, 25, 0.1) 0%, transparent 40%),
        linear-gradient(180deg, transparent 0%, rgba(8, 8, 12, 0.6) 70%, var(--bg-deep) 100%);
}
.hero-bg .talisman {
    position: absolute;
    font-size: clamp(120px, 25vw, 300px);
    opacity: 0.04;
    color: var(--gold);
    user-select: none;
    pointer-events: none;
}
.hero-bg .talisman-1 { top: 5%; left: 5%; transform: rotate(-15deg); }
.hero-bg .talisman-2 { bottom: 10%; right: 5%; transform: rotate(10deg); font-size: clamp(80px, 18vw, 220px); }

.hero-content {
    max-width: 800px;
    z-index: 2;
}
.hero-badge {
    display: inline-block;
    background: rgba(200, 40, 30, 0.15);
    border: 1px solid rgba(200, 40, 30, 0.35);
    color: var(--red-bright);
    padding: 6px 20px;
    border-radius: 25px;
    font-size: 0.85rem;
    letter-spacing: 4px;
    margin-bottom: 24px;
    animation: fadeInDown 0.8s ease;
}
.hero-title {
    font-size: clamp(2.2rem, 6vw, 3.8rem);
    font-weight: 900;
    letter-spacing: 8px;
    margin-bottom: 8px;
    background: linear-gradient(180deg, #fff8e7 0%, #d4a574 50%, #a67c3d 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    filter: drop-shadow(0 2px 8px rgba(201, 169, 110, 0.3));
    animation: fadeInUp 0.8s ease;
}
.hero-subtitle {
    font-size: clamp(1rem, 2vw, 1.35rem);
    color: var(--text-dim);
    letter-spacing: 6px;
    margin-bottom: 12px;
    animation: fadeInUp 0.8s ease 0.1s both;
}
.hero-slogan {
    font-size: 1rem;
    color: var(--red-bright);
    letter-spacing: 4px;
    margin-bottom: 36px;
    animation: fadeInUp 0.8s ease 0.2s both;
    text-shadow: 0 0 20px rgba(232, 69, 60, 0.4);
}
.hero-btns {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
    animation: fadeInUp 0.8s ease 0.3s both;
}
/* QR码弹窗 */
.btn-qr-wrapper {
    position: relative;
    display: inline-flex;
}
.qr-popup {
    position: absolute;
    bottom: calc(100% + 16px);
    left: 50%;
    transform: translateX(-50%);
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    transition: opacity 0.25s ease, visibility 0.25s ease;
    z-index: 100;
}
.qr-popup.show {
    opacity: 1;
    visibility: visible;
}
.qr-popup-inner {
    background: rgba(20, 16, 36, 0.97);
    border: 1px solid var(--gold);
    border-radius: var(--radius-md);
    padding: 12px;
    text-align: center;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.6), 0 0 20px rgba(201, 169, 110, 0.15);
}
.qr-popup-inner .qr-code {
    width: 160px;
    height: 160px;
}
.qr-popup-inner .qr-code canvas,
.qr-popup-inner .qr-code img {
    display: block;
    width: 160px;
    height: 160px;
}
.qr-popup-inner p {
    margin: 8px 0 0;
    font-size: 0.8rem;
    color: var(--gold);
    letter-spacing: 1px;
}
/* CTA二维码 */
.cta-qr {
    margin-top: 24px;
    display: flex;
    justify-content: center;
}
.cta-qr .qr-code {
    width: 160px;
    height: 160px;
}
.cta-qr .qr-code canvas,
.cta-qr .qr-code img {
    display: block;
    width: 160px;
    height: 160px;
}
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 36px;
    border-radius: 30px;
    font-size: 1rem;
    font-weight: 700;
    letter-spacing: 3px;
    text-decoration: none;
    cursor: pointer;
    border: none;
    transition: all 0.35s ease;
    font-family: inherit;
    position: relative;
    overflow: hidden;
}
.btn::after {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: 30px;
    opacity: 0;
    transition: opacity 0.35s ease;
}
.btn:hover::after { opacity: 1; }
.btn-primary {
    background: linear-gradient(135deg, #b5281c, #d94030, #b5281c);
    color: #fff;
    box-shadow: 0 6px 30px rgba(200, 40, 30, 0.45);
    background-size: 200% 100%;
    animation: shimmer 3s ease infinite;
}
.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 40px rgba(220, 50, 35, 0.6);
}
.btn-secondary {
    background: transparent;
    color: var(--gold-light);
    border: 2px solid var(--border);
}
.btn-secondary:hover {
    border-color: var(--gold-light);
    background: rgba(201, 169, 110, 0.08);
    transform: translateY(-3px);
    box-shadow: var(--shadow-gold);
}
.hero-stats {
    display: flex;
    justify-content: center;
    gap: clamp(24px, 5vw, 60px);
    margin-top: 56px;
    animation: fadeInUp 0.8s ease 0.4s both;
}
.hero-stat {
    text-align: center;
}
.hero-stat .num {
    font-size: clamp(1.5rem, 3vw, 2.2rem);
    font-weight: 900;
    color: var(--gold-light);
    letter-spacing: 2px;
}
.hero-stat .label {
    font-size: 0.8rem;
    color: var(--text-muted);
    letter-spacing: 3px;
    margin-top: 4px;
}
.hero-scroll {
    position: absolute;
    bottom: 32px;
    left: 50%;
    transform: translateX(-50%);
    animation: bounce 2s ease infinite;
    opacity: 0.5;
}
.hero-scroll span {
    display: block;
    width: 24px;
    height: 24px;
    border-right: 2px solid var(--gold-light);
    border-bottom: 2px solid var(--gold-light);
    transform: rotate(45deg);
}

/* ===== 通用区块 ===== */
.section {
    position: relative;
    z-index: 1;
    padding: 100px 24px;
}
.section-inner {
    max-width: 1200px;
    margin: 0 auto;
}
.section-label {
    text-align: center;
    font-size: 0.8rem;
    letter-spacing: 6px;
    color: var(--red-bright);
    margin-bottom: 12px;
    text-transform: uppercase;
}
.section-title {
    text-align: center;
    font-size: clamp(1.6rem, 3.5vw, 2.4rem);
    font-weight: 900;
    letter-spacing: 6px;
    margin-bottom: 16px;
    color: var(--gold-light);
}
.section-desc {
    text-align: center;
    color: var(--text-dim);
    font-size: 0.95rem;
    letter-spacing: 2px;
    max-width: 600px;
    margin: 0 auto 60px;
    line-height: 1.8;
}
.divider {
    width: 60px;
    height: 3px;
    background: linear-gradient(90deg, transparent, var(--red-bright), transparent);
    margin: 16px auto;
    border-radius: 2px;
}

/* ===== 关于游戏 ===== */
.about {
    background: linear-gradient(180deg, var(--bg-deep) 0%, rgba(12,10,16,1) 40%, var(--bg-deep) 100%);
}
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: center;
}
.about-visual {
    position: relative;
    border-radius: var(--radius-lg);
    overflow: hidden;
    aspect-ratio: 16/10;
    box-shadow: 0 20px 60px rgba(0,0,0,0.6);
}
.about-visual img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}
.about-visual::after {
    content: '';
    position: absolute;
    inset: 0;
    border: 2px solid var(--border);
    border-radius: var(--radius-lg);
    pointer-events: none;
}
.about-visual::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(180deg, transparent 60%, rgba(8,8,12,0.7) 100%);
    z-index: 1;
    pointer-events: none;
}
.about-text h3 {
    font-size: 1.4rem;
    color: var(--gold-light);
    letter-spacing: 4px;
    margin-bottom: 20px;
}
.about-text p {
    color: var(--text-dim);
    font-size: 0.95rem;
    letter-spacing: 1.5px;
    line-height: 2;
    margin-bottom: 16px;
}
.about-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 24px;
}
.tag {
    padding: 6px 18px;
    border: 1px solid var(--border);
    border-radius: 20px;
    color: var(--gold-light);
    font-size: 0.8rem;
    letter-spacing: 2px;
    transition: all 0.3s;
}
.tag:hover {
    background: rgba(201, 169, 110, 0.1);
    border-color: var(--gold-light);
}

/* ===== 特色功能 ===== */
.features {
    background:
        radial-gradient(ellipse 60% 50% at 50% 0%, rgba(200, 40, 30, 0.05) 0%, transparent 70%);
}
.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}
.feature-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 40px 28px;
    text-align: center;
    transition: all 0.4s ease;
    position: relative;
    overflow: hidden;
}
.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60%;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--border-glow), transparent);
    transition: width 0.4s ease;
}
.feature-card:hover {
    transform: translateY(-8px);
    border-color: var(--border-glow);
    box-shadow: 0 20px 50px rgba(0,0,0,0.5), 0 0 30px rgba(201, 169, 110, 0.08);
}
.feature-card:hover::before {
    width: 80%;
}
.feature-icon {
    font-size: 3rem;
    margin-bottom: 16px;
    display: block;
    filter: drop-shadow(0 0 10px rgba(201,169,110,0.3));
}
.feature-card h4 {
    font-size: 1.1rem;
    color: var(--gold-light);
    letter-spacing: 4px;
    margin-bottom: 12px;
}
.feature-card p {
    color: var(--text-dim);
    font-size: 0.85rem;
    letter-spacing: 1.5px;
    line-height: 1.8;
}

/* ===== 福利模块 ===== */
.rewards {
    background: linear-gradient(180deg, var(--bg-deep) 0%, rgba(14, 10, 18, 1) 50%, var(--bg-deep) 100%);
}
.rewards-hero-card {
    background: linear-gradient(135deg, rgba(180, 35, 25, 0.12), rgba(201, 169, 110, 0.06));
    border: 1px solid rgba(200, 40, 30, 0.3);
    border-radius: var(--radius-lg);
    padding: 48px 36px;
    text-align: center;
    margin-bottom: 40px;
    position: relative;
    overflow: hidden;
}
.rewards-hero-card::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: conic-gradient(from 0deg, transparent, rgba(200,40,30,0.05), transparent, rgba(201,169,110,0.04), transparent);
    animation: rotateConic 20s linear infinite;
}
.rewards-hero-card > * { position: relative; z-index: 1; }
.rewards-big-num {
    font-size: clamp(3rem, 8vw, 5rem);
    font-weight: 900;
    letter-spacing: 6px;
    background: linear-gradient(180deg, #fff8e7 0%, #e8c97a 40%, #c9a96e 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    filter: drop-shadow(0 4px 15px rgba(201, 169, 110, 0.4));
}
.rewards-big-label {
    color: var(--text-dim);
    letter-spacing: 4px;
    margin-top: 8px;
    font-size: 1rem;
}
.rewards-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
}
.reward-item {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 28px 24px;
    display: flex;
    align-items: center;
    gap: 20px;
    transition: all 0.35s ease;
}
.reward-item:hover {
    border-color: var(--border-glow);
    transform: translateY(-4px);
    box-shadow: 0 12px 40px rgba(0,0,0,0.4);
}
.reward-icon {
    font-size: 2.5rem;
    flex-shrink: 0;
}
.reward-info h5 {
    color: var(--gold-light);
    letter-spacing: 3px;
    font-size: 0.95rem;
    margin-bottom: 6px;
}
.reward-info p {
    color: var(--text-dim);
    font-size: 0.82rem;
    letter-spacing: 1.5px;
    line-height: 1.6;
}

/* ===== 截图展示 ===== */
.screenshots {
    overflow: hidden;
}
.screenshot-wrapper {
    position: relative;
    display: flex;
    align-items: center;
}
.screenshot-arrow {
    flex-shrink: 0;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    border: 1px solid var(--border);
    background: rgba(12, 10, 24, 0.85);
    color: var(--gold);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
    z-index: 2;
    backdrop-filter: blur(8px);
}
.screenshot-arrow:hover {
    border-color: var(--gold);
    background: rgba(201, 169, 110, 0.15);
    box-shadow: 0 0 20px rgba(201, 169, 110, 0.25);
}
.screenshot-arrow:active {
    transform: scale(0.92);
}
.screenshot-arrow svg {
    width: 22px;
    height: 22px;
}
.screenshot-arrow-left {
    margin-right: 12px;
}
.screenshot-arrow-right {
    margin-left: 12px;
}
.screenshot-scroll {
    display: flex;
    gap: 20px;
    overflow-x: auto;
    scroll-snap-type: x mandatory;
    padding: 10px 0 20px;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
}
.screenshot-scroll::-webkit-scrollbar { display: none; }
.screenshot-item {
    flex: 0 0 clamp(400px, 55vw, 780px);
    scroll-snap-align: start;
    border-radius: var(--radius-lg);
    overflow: hidden;
    border: 1px solid var(--border);
    transition: all 0.35s ease;
    cursor: pointer;
}
.screenshot-item:hover {
    border-color: var(--border-glow);
    transform: translateY(-6px);
    box-shadow: 0 16px 50px rgba(0,0,0,0.6);
}
.screenshot-item img {
    width: 100%;
    display: block;
    aspect-ratio: 1556 / 894;
    object-fit: cover;
}
.screenshot-nav {
    display: flex;
    justify-content: center;
    gap: 12px;
    margin-top: 24px;
}
.screenshot-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--border);
    border: none;
    cursor: pointer;
    transition: all 0.3s;
}
.screenshot-dot.active {
    background: var(--red-bright);
    box-shadow: 0 0 10px rgba(200,40,30,0.6);
    transform: scale(1.3);
}

/* ===== CTA区域 ===== */
.cta-section {
    text-align: center;
    background:
        radial-gradient(ellipse 60% 40% at 50% 50%, rgba(200, 40, 30, 0.08) 0%, transparent 70%);
}
.cta-section .section-title {
    font-size: clamp(1.8rem, 4vw, 2.6rem);
}
.cta-btns {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
    margin-top: 36px;
}
.cta-note {
    color: var(--text-muted);
    font-size: 0.8rem;
    letter-spacing: 2px;
    margin-top: 24px;
}

/* ===== 页脚 ===== */
.footer {
    border-top: 1px solid rgba(201, 169, 110, 0.1);
    padding: 40px 24px;
    text-align: center;
    z-index: 1;
    position: relative;
}
.footer-inner {
    max-width: 1200px;
    margin: 0 auto;
}
.footer-links {
    display: flex;
    justify-content: center;
    gap: 24px;
    flex-wrap: wrap;
    margin-bottom: 16px;
}
.footer-links a {
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.8rem;
    letter-spacing: 2px;
    transition: color 0.3s;
}
.footer-links a:hover { color: var(--gold-light); }
.footer-friend-links {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 16px;
    flex-wrap: wrap;
    margin-bottom: 16px;
    padding-top: 12px;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
}
.friend-links-label {
    color: var(--text-muted);
    font-size: 0.78rem;
    letter-spacing: 1px;
}
.footer-friend-links a {
    color: var(--text-dim);
    text-decoration: none;
    font-size: 0.78rem;
    letter-spacing: 1px;
    transition: color 0.3s, transform 0.3s;
}
.footer-friend-links a:hover {
    color: var(--gold-light);
    transform: translateY(-1px);
}
.footer-copy {
    color: var(--text-muted);
    font-size: 0.75rem;
    letter-spacing: 2px;
}

/* ===== 光效动画 ===== */
@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}
@keyframes fadeInDown {
    from { opacity: 0; transform: translateY(-20px); }
    to { opacity: 1; transform: translateY(0); }
}
@keyframes shimmer {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}
@keyframes bounce {
    0%, 100% { transform: translateX(-50%) translateY(0); }
    50% { transform: translateX(-50%) translateY(12px); }
}
@keyframes rotateConic {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}
@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}
@keyframes pulse {
    0%, 100% { opacity: 0.5; }
    50% { opacity: 1; }
}

/* ===== 返回顶部 ===== */
.back-to-top {
    position: fixed;
    right: 32px;
    bottom: 32px;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    border: 1px solid var(--gold);
    background: rgba(12, 10, 24, 0.85);
    color: var(--gold);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 99;
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: all 0.35s ease;
    backdrop-filter: blur(8px);
}
.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}
.back-to-top:hover {
    border-color: var(--gold);
    background: rgba(201, 169, 110, 0.15);
    box-shadow: 0 0 20px rgba(201, 169, 110, 0.25);
    transform: translateY(-3px);
}
.back-to-top.visible:hover {
    transform: translateY(-3px);
}
.back-to-top svg {
    width: 22px;
    height: 22px;
}

.reveal {
    opacity: 0;
    transform: translateY(40px);
    transition: all 0.7s cubic-bezier(0.22, 0.61, 0.36, 1);
}
.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ===== 响应式 ===== */
@media (max-width: 968px) {
    .about-grid {
        grid-template-columns: 1fr;
        gap: 32px;
    }
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .rewards-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 640px) {
    .nav-links {
        position: fixed;
        top: 64px;
        left: 0;
        right: 0;
        flex-direction: column;
        background: rgba(6, 5, 9, 0.97);
        backdrop-filter: blur(20px);
        padding: 24px;
        gap: 20px;
        align-items: center;
        border-bottom: 1px solid var(--border);
        transform: translateY(-120%);
        opacity: 0;
        transition: all 0.35s ease;
        pointer-events: none;
    }
    .nav-links.open {
        transform: translateY(0);
        opacity: 1;
        pointer-events: auto;
    }
    .menu-toggle {
        display: flex;
    }
    .features-grid {
        grid-template-columns: 1fr;
    }
    .hero-stats {
        gap: 28px;
    }
    .about-visual {
        aspect-ratio: 16/11;
    }
    .btn {
        padding: 12px 28px;
        font-size: 0.9rem;
    }
    .section {
        padding: 64px 16px;
    }
    .rewards-hero-card {
        padding: 32px 20px;
    }
    .reward-item {
        flex-direction: column;
        text-align: center;
    }
    .screenshot-arrow {
        display: none;
    }
    .back-to-top {
        right: 16px;
        bottom: 16px;
        width: 40px;
        height: 40px;
    }
}