/* Reset and base styles */
:root {
    --bg-dark: #121212; /* 钛合金暗灰背景 */
    --bg-panel: #1a1a1a;
    --primary: #FFD700; /* 高能警示黄 */
    --secondary: #00F0FF; /* 机甲电光蓝 */
    --danger: #FF003C; /* 警告红 */
    --text-main: #e0e0e0;
    --text-muted: #888899;
    --border-color: #333344;
}

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

body {
    font-family: 'Courier New', Courier, monospace; /* Cyberpunk/HUD feel */
    line-height: 1.6;
    color: var(--text-main);
    background-color: var(--bg-dark);
    position: relative;
    overflow-x: hidden;
}

/* 雷达扫描网格线 */
body::before {
    content: "";
    position: fixed;
    top: 0; left: 0; width: 100vw; height: 100vh;
    background-image: 
        linear-gradient(rgba(0, 240, 255, 0.05) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0, 240, 255, 0.05) 1px, transparent 1px);
    background-size: 50px 50px;
    z-index: -2;
    pointer-events: none;
}

/* 红色警告扫描光束 */
body::after {
    content: "";
    position: fixed;
    top: -10px; left: 0; width: 100vw; height: 2px;
    background: var(--danger);
    box-shadow: 0 0 10px var(--danger), 0 0 20px var(--danger);
    z-index: 9999;
    pointer-events: none;
    animation: scanline 8s linear infinite;
    opacity: 0.7;
}

@keyframes scanline {
    0% { top: -10px; }
    100% { top: 100vh; }
}

a {
    text-decoration: none;
    color: var(--secondary);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    position: relative;
    z-index: 10;
}

/* Header */
header {
    background-color: rgba(18, 18, 18, 0.9);
    border-bottom: 2px solid var(--primary);
    box-shadow: 0 0 20px rgba(255, 215, 0, 0.2);
    position: sticky;
    top: 0;
    z-index: 1000;
    backdrop-filter: blur(10px);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 0;
}

.logo {
    font-size: 1.5rem;
    font-weight: 900;
    color: var(--primary);
    text-transform: uppercase;
    letter-spacing: 2px;
    text-shadow: 0 0 10px rgba(255, 215, 0, 0.5);
}

.main-nav {
    display: flex;
    align-items: center;
    gap: 25px;
}

.main-nav a:not(.btn-sm) {
    color: var(--text-main);
    font-weight: bold;
    text-transform: uppercase;
    transition: all 0.3s;
    border-bottom: 2px solid transparent;
}

.main-nav a:not(.btn-sm):hover {
    color: var(--secondary);
    border-bottom: 2px solid var(--secondary);
    text-shadow: 0 0 8px var(--secondary);
}

/* Buttons */
.btn, .btn-sm {
    display: inline-block;
    padding: 12px 30px;
    background-color: transparent;
    color: var(--primary) !important;
    font-weight: bold;
    text-transform: uppercase;
    text-align: center;
    transition: all 0.3s;
    border: 2px solid var(--primary);
    cursor: pointer;
    /* 切角装甲造型 */
    clip-path: polygon(15px 0, 100% 0, 100% calc(100% - 15px), calc(100% - 15px) 100%, 0 100%, 0 15px);
    position: relative;
}
.btn-sm { padding: 8px 20px; }

.btn:hover, .btn-sm:hover {
    background-color: var(--primary);
    color: var(--bg-dark) !important;
    box-shadow: 0 0 20px var(--primary);
}

/* Hero Section */
.hero {
    text-align: center;
    padding: 100px 20px;
    background: transparent;
    position: relative;
    border-bottom: 1px dashed var(--border-color);
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 20px;
    font-weight: 900;
    color: var(--primary);
    text-shadow: 3px 3px 0px var(--danger);
    letter-spacing: 2px;
}

.hero p {
    font-size: 1.25rem;
    color: var(--secondary);
    margin-bottom: 40px;
    text-shadow: 0 0 8px rgba(0, 240, 255, 0.4);
    max-width: 60%;
    margin-left: auto;
    margin-right: auto;
}

/* Section Common */
section {
    padding: 80px 0;
}

.bg-white {
    background-color: transparent !important;
}

h2.section-title {
    text-align: center;
    font-size: 2.2rem;
    margin-bottom: 50px;
    font-weight: 900;
    color: var(--text-main);
    text-transform: uppercase;
}

h2.section-title::before, h2.section-title::after {
    content: " /// ";
    color: var(--secondary);
    opacity: 0.5;
}

/* Grid Layout */
.grid-3 {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}
.grid-2 {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 30px;
}

/* Tactical Armor Plates (Cards) */
.card {
    background: linear-gradient(135deg, var(--bg-panel) 0%, #111 100%);
    padding: 40px 30px;
    text-align: center;
    transition: transform 0.3s ease;
    border: 1px solid var(--border-color);
    border-left: 4px solid var(--secondary);
    clip-path: polygon(25px 0, 100% 0, 100% calc(100% - 25px), calc(100% - 25px) 100%, 0 100%, 0 25px);
    position: relative;
}

/* Rivets */
.card::before {
    content: "●";
    position: absolute;
    top: 10px; right: 15px;
    color: #444;
    font-size: 12px;
}

.card:hover {
    transform: translateY(-5px);
    border-left-color: var(--primary);
    box-shadow: 0 0 30px rgba(0, 240, 255, 0.2);
}

.icon {
    font-size: 3rem;
    margin-bottom: 20px;
    filter: drop-shadow(0 0 10px var(--secondary));
}

.card h3 {
    font-size: 1.5rem;
    margin-bottom: 15px;
    color: var(--primary);
}

.card p {
    color: var(--text-muted);
}

/* Pricing Table (Carousel prepared) */
.pricing-table {
    display: flex;
    justify-content: center;
    gap: 30px;
    perspective: 1000px;
}

.price-card {
    background: linear-gradient(135deg, var(--bg-panel) 0%, #111 100%);
    padding: 50px 30px;
    text-align: center;
    flex: 1;
    max-width: 380px;
    border: 1px solid var(--border-color);
    border-top: 4px solid var(--secondary);
    clip-path: polygon(0 0, calc(100% - 30px) 0, 100% 30px, 100% 100%, 30px 100%, 0 calc(100% - 30px));
    position: relative;
    transition: transform 0.5s ease;
    transform-style: preserve-3d;
}

.price-card:hover {
    transform: translateZ(30px) rotateY(5deg);
    border-top-color: var(--primary);
    box-shadow: -10px 10px 30px rgba(0, 0, 0, 0.8), 0 0 20px rgba(255, 215, 0, 0.2);
}

.price-card.popular {
    border-top: 4px solid var(--danger);
    transform: scale(1.05) translateZ(10px);
}
.price-card.popular:hover {
    transform: scale(1.05) translateZ(40px) rotateY(-5deg);
}

.popular-badge {
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    background: var(--danger);
    color: var(--bg-dark);
    padding: 5px 20px;
    font-weight: 900;
    font-size: 0.9rem;
    clip-path: polygon(10px 0, calc(100% - 10px) 0, 100% 100%, 0 100%);
}

.price-card h3 {
    font-size: 1.8rem;
    margin-bottom: 10px;
    color: var(--primary);
    margin-top: 15px;
}

.price-card .price {
    font-size: 3rem;
    font-weight: 900;
    color: var(--text-main);
    margin: 20px 0;
    text-shadow: 0 0 10px rgba(255, 255, 255, 0.2);
}

.price-card .price span {
    font-size: 1rem;
    color: var(--secondary);
    font-weight: normal;
}

.price-card ul {
    list-style: none;
    margin-bottom: 40px;
    text-align: left;
}

.price-card ul li {
    margin-bottom: 15px;
    padding-left: 30px;
    position: relative;
    color: var(--text-muted);
}
.price-card ul li::before {
    content: ">";
    color: var(--secondary);
    font-weight: bold;
    position: absolute;
    left: 0;
}

/* FAQ Accordion */
.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    background: var(--bg-panel);
    margin-bottom: 15px;
    padding: 20px 25px;
    border: 1px solid var(--border-color);
    border-left: 3px solid var(--primary);
    clip-path: polygon(0 0, 100% 0, 100% calc(100% - 10px), calc(100% - 10px) 100%, 0 100%);
    cursor: pointer;
    transition: all 0.3s;
}

.faq-item:hover, .faq-item.active {
    background: #222;
    border-left-color: var(--danger);
}

.faq-item h4 {
    font-size: 1.1rem;
    color: var(--secondary);
    margin: 0;
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.faq-item h4::after {
    content: "[+]";
    color: var(--text-muted);
}
.faq-item.active h4::after {
    content: "[-]";
    color: var(--primary);
}

.faq-item p {
    color: var(--text-main);
    margin-top: 15px;
    display: none; /* JS will toggle */
    padding-top: 15px;
    border-top: 1px dashed var(--border-color);
}

/* Reviews seamless scroll container */
.reviews-container {
    overflow: hidden;
    position: relative;
    width: 100%;
}
.reviews {
    display: flex;
    gap: 30px;
    width: max-content;
    animation: scroll-left 20s linear infinite;
}
.reviews .card {
    text-align: left;
    width: 350px;
    flex-shrink: 0;
}
.reviews:hover {
    animation-play-state: paused;
}
@keyframes scroll-left {
    0% { transform: translateX(0); }
    100% { transform: translateX(-50%); }
}

.reviews .stars {
    color: var(--primary);
    font-size: 1.2rem;
    margin-bottom: 15px;
    letter-spacing: 2px;
}
.reviews .author {
    font-weight: bold;
    margin-top: 20px;
    color: var(--secondary);
}

/* Footer */
footer {
    background-color: #050505;
    color: var(--text-muted);
    padding: 60px 0 30px;
    text-align: center;
    border-top: 2px solid var(--secondary);
    position: relative;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 30px;
    margin-bottom: 20px;
    flex-wrap: wrap;
}

.footer-links a {
    color: var(--secondary);
    font-size: 1rem;
    text-transform: uppercase;
}

.footer-links a:hover {
    color: var(--primary);
    text-shadow: 0 0 8px var(--primary);
}

.pbn-links {
    margin: 30px 0;
    padding: 15px;
    border: 1px dashed var(--border-color);
    font-size: 0.8rem;
}
.pbn-links span {
    color: #555;
    margin-right: 10px;
}
.pbn-links a {
    color: #666;
    margin: 0 10px;
}
.pbn-links a:hover {
    color: var(--secondary);
}

/* HUD Overlay Display */
.hud-dashboard {
    position: fixed;
    bottom: 20px;
    left: 20px;
    background: rgba(10, 10, 15, 0.85);
    border: 1px solid var(--secondary);
    border-left: 4px solid var(--danger);
    padding: 15px;
    width: 280px;
    height: 100px;
    overflow: hidden;
    z-index: 1000;
    pointer-events: none;
    clip-path: polygon(0 0, 100% 0, 100% calc(100% - 15px), calc(100% - 15px) 100%, 0 100%);
    box-shadow: 0 0 15px rgba(0, 240, 255, 0.2);
}
.hud-title {
    font-size: 0.7rem;
    color: var(--danger);
    margin-bottom: 8px;
    border-bottom: 1px solid #333;
    padding-bottom: 4px;
    letter-spacing: 1px;
}
.hud-text-container {
    position: relative;
    height: 60px;
    overflow: hidden;
}
.hud-scroller {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    color: var(--primary);
    font-size: 0.85rem;
    animation: hud-scroll 8s steps(1, end) infinite;
}
.hud-scroller div {
    height: 60px;
    display: flex;
    align-items: flex-start;
}
@keyframes hud-scroll {
    0% { transform: translateY(0); }
    25% { transform: translateY(-60px); }
    50% { transform: translateY(-120px); }
    75% { transform: translateY(-180px); }
    100% { transform: translateY(0); }
}

/* SVG Mecha Duck Hero Image */
.hero-duck-container {
    position: absolute;
    right: 5%;
    top: 50%;
    transform: translateY(-50%);
    width: 350px;
    height: 350px;
    pointer-events: none;
    z-index: 0;
    animation: hover-mech 4s ease-in-out infinite;
}
@keyframes hover-mech {
    0%, 100% { transform: translateY(-50%); }
    50% { transform: translateY(-55%); }
}

/* Mobile Adjustments */
@media (max-width: 768px) {
    .header-content { flex-direction: column; gap: 15px; }
    .main-nav { flex-wrap: wrap; justify-content: center; gap: 15px; }
    .grid-3, .grid-2 { grid-template-columns: 1fr; }
    .pricing-table { flex-direction: column; align-items: center; }
    .price-card { width: 100%; transform: none !important; }
    .hero { padding: 60px 20px; }
    .hero h1 { font-size: 2.2rem; }
    .hero p { max-width: 100%; }
    .btn, .btn-sm { width: 100%; display: block; box-sizing: border-box; }
    .hud-dashboard { display: none; }
    .hero-duck-container { opacity: 0.2; right: 50%; transform: translate(50%, -50%); }
    .reviews { animation: none; flex-wrap: wrap; width: 100%; }
    .reviews .card { width: 100%; }
}


/* Phase 2 A11y & Layout Fixes */
.skip-link {
    position: absolute;
    top: -40px;
    left: 0;
    background: var(--primary);
    color: #000;
    padding: 8px;
    z-index: 10000;
    transition: top 0.2s;
}
.skip-link:focus {
    top: 0;
}
:target {
    scroll-margin-top: 100px;
}
section, [id] {
    scroll-margin-top: 100px;
}
details.faq-item {
    margin-bottom: 15px;
    border-bottom: 1px solid #222;
    padding-bottom: 10px;
}
details.faq-item summary {
    cursor: pointer;
    font-weight: bold;
    color: var(--secondary);
    padding: 10px 0;
}
details.faq-item summary h4 {
    display: inline;
    margin: 0;
}
details.faq-item div.faq-answer {
    padding: 10px 0;
    color: var(--text-main);
}