/* ==========================================================================
   🍀 本地商户共享私域协作平台 - CSS 视觉系统
   ========================================================================== */

/* 1. Design System & CSS Variables */
:root {
    --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    --font-display: var(--font-sans);
    
    /* Sleek Dark Palette (HSL tailored) */
    --color-bg-deep: hsl(224, 71%, 4%);
    --color-bg-card: hsla(222, 47%, 10%, 0.65);
    --color-bg-card-hover: hsla(222, 47%, 14%, 0.85);
    --color-bg-nav: hsla(224, 71%, 4%, 0.85);
    
    /* Grains of colors */
    --color-text-primary: hsl(210, 40%, 98%);
    --color-text-secondary: hsl(215, 20%, 65%);
    --color-text-muted: hsl(215, 14%, 45%);
    
    /* Accents (Aurora Theme: Emerald Green & Electric Blue) */
    --color-primary: hsl(150, 84%, 48%);
    --color-primary-hover: hsl(152, 90%, 40%);
    --color-primary-glow: hsla(150, 84%, 48%, 0.15);
    
    --color-secondary: hsl(217, 91%, 60%);
    --color-secondary-hover: hsl(217, 91%, 50%);
    --color-secondary-glow: hsla(217, 91%, 60%, 0.15);
    
    --color-accent-red: hsl(354, 70%, 54%);
    --color-accent-red-glow: hsla(354, 70%, 54%, 0.2);
    
    /* Boarders & Shadows */
    --border-glass: 1px solid hsla(217, 30%, 50%, 0.15);
    --border-focus: 1px solid hsl(150, 84%, 48%);
    --shadow-main: 0 8px 32px 0 rgba(0, 0, 0, 0.4);
    --shadow-glow: 0 0 20px 0 hsla(150, 84%, 48%, 0.35);
    
    /* Layout */
    --container-width: 1200px;
    --header-height: 80px;
    --border-radius-lg: 16px;
    --border-radius-md: 8px;
    --transition-fast: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-normal: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

/* 2. Base Reset */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    background-color: var(--color-bg-deep);
    color: var(--color-text-primary);
    font-family: var(--font-sans);
    line-height: 1.6;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

img, svg {
    max-width: 100%;
    height: auto;
    display: block;
}

ul {
    list-style: none;
}

a {
    color: inherit;
    text-decoration: none;
    transition: var(--transition-fast);
}

/* 3. Utility Classes */
.container {
    width: 100%;
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 1.5rem;
}

.text-center { text-align: center; }
.text-gradient {
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-secondary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.highlight-green { color: var(--color-primary); font-weight: 600; }
.highlight-blue { color: var(--color-secondary); font-weight: 600; }
.highlight-red { color: var(--color-accent-red); font-weight: 600; }

.glass-card {
    background: var(--color-bg-card);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: var(--border-glass);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-main);
    transition: var(--transition-normal);
}

.glass-card:hover {
    background: var(--color-bg-card-hover);
    border-color: hsla(217, 30%, 60%, 0.25);
    transform: translateY(-4px);
}

/* 4. Button System */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-family: var(--font-display);
    font-weight: 600;
    border-radius: var(--border-radius-md);
    cursor: pointer;
    transition: var(--transition-fast);
    border: 1px solid transparent;
}

.btn-primary {
    background: linear-gradient(135deg, var(--color-primary) 0%, hsl(160, 90%, 40%) 100%);
    color: hsl(224, 71%, 4%);
    box-shadow: 0 4px 15px rgba(16, 185, 129, 0.3);
}

.btn-primary:hover {
    background: linear-gradient(135deg, hsl(152, 90%, 40%) 0%, hsl(160, 90%, 35%) 100%);
    box-shadow: 0 6px 20px rgba(16, 185, 129, 0.45), var(--shadow-glow);
    transform: translateY(-2px);
}

.btn-secondary {
    background: transparent;
    color: var(--color-text-primary);
    border: 1px solid hsla(210, 40%, 98%, 0.2);
}

.btn-secondary:hover {
    background: hsla(210, 40%, 98%, 0.05);
    border-color: var(--color-text-primary);
    transform: translateY(-2px);
}

.btn-lg {
    padding: 0.9rem 2rem;
    font-size: 1.05rem;
}

.btn-sm {
    padding: 0.5rem 1.2rem;
    font-size: 0.9rem;
}

.btn-block {
    width: 100%;
}

/* 5. Header & Navigation */
.main-header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: var(--header-height);
    background: var(--color-bg-nav);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: var(--border-glass);
    z-index: 1000;
    display: flex;
    align-items: center;
    transition: var(--transition-fast);
}

.main-header.scrolled {
    height: 70px;
    background: var(--color-bg-deep);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.5);
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.6rem;
}

.logo-icon {
    font-size: 1.6rem;
}

.logo-text {
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 1.35rem;
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-secondary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: -0.5px;
}

.nav-links {
    display: flex;
    gap: 2rem;
}

.nav-link {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--color-text-secondary);
}

.nav-link:hover, .nav-link.active {
    color: var(--color-primary);
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: space-between;
    width: 24px;
    height: 18px;
    background: transparent;
    border: none;
    cursor: pointer;
}

.mobile-menu-toggle span {
    width: 100%;
    height: 2px;
    background-color: var(--color-text-primary);
    transition: var(--transition-fast);
}

/* 6. Hero Section */
.hero-section {
    position: relative;
    padding-top: calc(var(--header-height) + 4rem);
    padding-bottom: 8rem;
    min-height: 80vh;
    display: flex;
    align-items: center;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-size: cover;
    background-position: center;
    opacity: 0.25;
    z-index: 1;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at 60% 40%, transparent 20%, var(--color-bg-deep) 75%);
    z-index: 2;
}

.hero-container {
    position: relative;
    z-index: 3;
}

.hero-content {
    max-width: 650px;
}

.badge {
    display: inline-block;
    background: var(--color-primary-glow);
    border: 1px solid rgba(16, 185, 129, 0.3);
    color: var(--color-primary);
    padding: 0.35rem 0.9rem;
    font-size: 0.85rem;
    font-weight: 600;
    border-radius: 50px;
    margin-bottom: 1.5rem;
    font-family: var(--font-display);
    letter-spacing: 0.5px;
}

.hero-title {
    font-family: var(--font-display);
    font-size: 3.5rem;
    font-weight: 700;
    line-height: 1.15;
    letter-spacing: -1.5px;
    margin-bottom: 1.5rem;
}

.hero-subtitle {
    font-size: 1.15rem;
    color: var(--color-text-secondary);
    margin-bottom: 2.5rem;
    line-height: 1.65;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
}

/* 7. Section Shared Styles */
section {
    padding: 6rem 0;
    position: relative;
}

.section-header {
    max-width: 600px;
    margin: 0 auto 4rem;
}

.section-title {
    font-family: var(--font-display);
    font-size: 2.25rem;
    font-weight: 700;
    margin-bottom: 1rem;
    letter-spacing: -0.5px;
}

.section-subtitle {
    color: var(--color-text-secondary);
    font-size: 1.05rem;
}

/* 8. Value Propositions (Tabs) */
.tabs-container {
    max-width: 1000px;
    margin: 0 auto;
}

.tabs-list {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    background: hsla(222, 47%, 8%, 0.7);
    border: var(--border-glass);
    border-radius: var(--border-radius-md);
    padding: 0.4rem;
    gap: 0.4rem;
    margin-bottom: 2.5rem;
}

.tab-btn {
    background: transparent;
    border: none;
    color: var(--color-text-secondary);
    padding: 0.9rem 1rem;
    font-family: var(--font-display);
    font-weight: 600;
    font-size: 0.95rem;
    border-radius: 6px;
    cursor: pointer;
    transition: var(--transition-fast);
}

.tab-btn:hover {
    color: var(--color-text-primary);
    background: hsla(210, 40%, 98%, 0.04);
}

.tab-btn.active {
    color: var(--color-bg-deep);
    background: var(--color-primary);
}

.tab-panel {
    display: none;
    animation: fadeIn 0.4s ease forwards;
}

.tab-panel.active {
    display: block;
}

.panel-grid {
    display: grid;
    grid-template-columns: 1.2fr 0.8fr;
    gap: 3rem;
    align-items: center;
}

.panel-title {
    font-family: var(--font-display);
    font-size: 1.6rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: var(--color-primary);
}

.panel-desc {
    color: var(--color-text-secondary);
    margin-bottom: 1.5rem;
}

.panel-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.panel-list li {
    position: relative;
    padding-left: 1.5rem;
    font-size: 0.95rem;
    color: var(--color-text-secondary);
}

.panel-list li::before {
    content: "✓";
    position: absolute;
    left: 0;
    color: var(--color-primary);
    font-weight: bold;
}

.panel-list li strong {
    color: var(--color-text-primary);
}

.visual-card {
    padding: 2rem;
    background: hsla(222, 47%, 12%, 0.8);
}

.visual-card:hover {
    transform: none;
    border-color: hsla(217, 30%, 50%, 0.15);
}

.visual-header {
    font-family: var(--font-display);
    font-weight: 600;
    font-size: 1.1rem;
    margin-bottom: 1.5rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    padding-bottom: 0.8rem;
}

.stat-row {
    display: flex;
    justify-content: space-between;
    padding: 0.6rem 0;
    font-size: 0.95rem;
}

.stat-row.highlight-row {
    padding-top: 1rem;
    border-top: 1px dashed rgba(255, 255, 255, 0.1);
}

.success-alert {
    background: var(--color-primary-glow);
    border: 1px solid rgba(16, 185, 129, 0.2);
    color: var(--color-primary);
    font-size: 0.85rem;
    padding: 0.75rem 1rem;
    border-radius: var(--border-radius-md);
    margin-top: 1.5rem;
    text-align: center;
}

.safety-indicator {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.85rem;
    background: var(--color-accent-red-glow);
    border: 1px solid rgba(239, 68, 68, 0.25);
    color: var(--color-accent-red);
    padding: 0.5rem 0.8rem;
    border-radius: var(--border-radius-md);
    margin-bottom: 1rem;
}

.indicator-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background-color: var(--color-accent-red);
}

/* 9. Features Grid */
.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.feature-card {
    padding: 2.5rem 2rem;
}

.feature-icon {
    font-size: 2rem;
    margin-bottom: 1.5rem;
    background: rgba(255, 255, 255, 0.03);
    width: 60px;
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--border-radius-md);
    border: var(--border-glass);
}

.feature-card-title {
    font-family: var(--font-display);
    font-size: 1.35rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.feature-card-desc {
    font-size: 0.9rem;
    color: var(--color-text-secondary);
    line-height: 1.6;
}

/* 10. Savings Calculator Section */
.calc-grid {
    display: grid;
    grid-template-columns: 0.95fr 1.05fr;
    gap: 4rem;
    align-items: center;
}

.calc-desc {
    color: var(--color-text-secondary);
    margin-bottom: 2rem;
}

.savings-highlight {
    background: linear-gradient(135deg, var(--color-primary-glow) 0%, var(--color-secondary-glow) 100%);
    border: var(--border-glass);
    border-radius: var(--border-radius-lg);
    padding: 2rem;
    text-align: center;
}

.savings-label {
    font-size: 0.95rem;
    color: var(--color-text-secondary);
    display: block;
    margin-bottom: 0.5rem;
}

.savings-value {
    font-family: var(--font-display);
    font-size: 3rem;
    font-weight: 700;
    color: var(--color-primary);
    text-shadow: 0 0 20px hsla(150, 84%, 48%, 0.2);
}

.savings-note {
    font-size: 0.85rem;
    color: var(--color-text-muted);
    margin-top: 0.5rem;
}

.calc-card {
    padding: 3rem 2.5rem;
}

.calc-card-title {
    font-family: var(--font-display);
    font-size: 1.6rem;
    font-weight: 700;
    margin-bottom: 2rem;
}

.form-group {
    margin-bottom: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.form-label {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--color-text-secondary);
}

.form-input {
    background: hsla(222, 47%, 6%, 0.8);
    border: var(--border-glass);
    border-radius: var(--border-radius-md);
    padding: 0.8rem 1rem;
    color: var(--color-text-primary);
    font-size: 1rem;
    transition: var(--transition-fast);
}

.form-input:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 10px rgba(16, 185, 129, 0.15);
}

.form-range {
    -webkit-appearance: none;
    width: 100%;
    height: 6px;
    border-radius: 5px;
    background: hsla(222, 47%, 6%, 0.8);
    outline: none;
}

.form-range::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--color-primary);
    cursor: pointer;
    box-shadow: 0 0 10px rgba(16, 185, 129, 0.5);
    transition: var(--transition-fast);
}

.form-range::-webkit-slider-thumb:hover {
    transform: scale(1.2);
}

.range-track-static {
    width: 100%;
    height: 6px;
    border-radius: 5px;
    background: hsla(222, 47%, 6%, 0.8);
    position: relative;
    overflow: hidden;
}

.range-track-fill {
    height: 100%;
    background: var(--color-secondary);
}

.calc-divider {
    border: none;
    border-top: 1px solid rgba(255, 255, 255, 0.08);
    margin: 2rem 0;
}

.calc-results {
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
}

.calc-results .result-row {
    display: flex;
    justify-content: space-between;
    font-size: 0.95rem;
}

.calc-results .result-row.highlight-row {
    font-size: 1.1rem;
    font-weight: 600;
    border-top: 1px dashed rgba(255, 255, 255, 0.1);
    padding-top: 0.8rem;
}

.result-val {
    font-family: var(--font-display);
}

/* 11. Splits Flow Section */
.splits-card-container {
    max-width: 1000px;
    margin: 0 auto;
}

.splits-card {
    display: grid;
    grid-template-columns: 0.8fr 1.2fr;
    overflow: hidden;
    padding: 0;
}

.splits-card:hover {
    transform: none;
}

.splits-inputs-panel {
    background: hsla(222, 47%, 6%, 0.5);
    padding: 3rem 2rem;
    border-right: 1px solid rgba(255, 255, 255, 0.05);
}

.splits-results-panel {
    padding: 3rem 2.5rem;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.splits-panel-title {
    font-family: var(--font-display);
    font-weight: 600;
    font-size: 1.15rem;
    margin-bottom: 2rem;
    letter-spacing: -0.2px;
}

.splits-flow {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
}

.flow-step {
    background: hsla(222, 47%, 16%, 0.8);
    border: var(--border-glass);
    border-radius: var(--border-radius-md);
    padding: 0.75rem 1.5rem;
    text-align: center;
    min-width: 200px;
}

.flow-step .step-label {
    font-size: 0.8rem;
    color: var(--color-text-secondary);
}

.flow-step .step-value {
    font-family: var(--font-display);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-primary);
}

.flow-arrow {
    font-size: 1.2rem;
    color: var(--color-text-muted);
}

.flow-dist {
    width: 100%;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1rem;
}

.dist-item {
    background: hsla(222, 47%, 4%, 0.6);
    border: var(--border-glass);
    border-radius: var(--border-radius-md);
    padding: 1rem;
    text-align: center;
}

.dist-item.fee-item {
    grid-column: span 2;
    background: transparent;
    border-style: dashed;
}

.dist-name {
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 0.35rem;
}

.dist-val {
    font-family: var(--font-display);
    font-size: 1.25rem;
    font-weight: 700;
}

.dist-desc {
    font-size: 0.75rem;
    color: var(--color-text-muted);
    margin-top: 0.25rem;
    line-height: 1.3;
}

.splits-verify-banner {
    background: hsla(217, 91%, 60%, 0.05);
    border: 1px solid rgba(59, 130, 246, 0.2);
    color: var(--color-text-secondary);
    padding: 0.8rem 1.2rem;
    border-radius: var(--border-radius-md);
    font-size: 0.8rem;
    line-height: 1.5;
    text-align: center;
    margin-top: 2rem;
}

/* 12. Join Section (WeChat Onboarding Promo) */
.join-container {
    max-width: 1000px;
    margin: 0 auto;
}

.join-promo-card {
    display: grid;
    grid-template-columns: 1fr;
    gap: 4rem;
    padding: 3rem 2.5rem;
}

.promo-item {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.promo-item-title {
    font-family: var(--font-display);
    font-size: 1.35rem;
    font-weight: 700;
    color: var(--color-primary);
}

.promo-item-desc {
    font-size: 0.95rem;
    color: var(--color-text-secondary);
    line-height: 1.6;
    margin-bottom: 0.5rem;
}

.promo-image-wrapper {
    width: 100%;
    background: hsla(222, 47%, 4%, 0.6);
    border: var(--border-glass);
    border-radius: var(--border-radius-md);
    overflow: hidden;
    position: relative;
    box-shadow: inset 0 0 20px rgba(0, 0, 0, 0.5);
    transition: var(--transition-normal);
}

.promo-image-wrapper:hover {
    border-color: var(--color-primary);
    box-shadow: inset 0 0 20px rgba(0, 0, 0, 0.5), 0 0 15px hsla(150, 84%, 48%, 0.2);
}

.promo-img {
    width: 100%;
    height: auto;
    display: block;
    transition: var(--transition-normal);
}

.promo-image-wrapper:hover .promo-img {
    transform: scale(1.01);
}

/* 13. Footer Area */
.main-footer {
    background: hsl(224, 71%, 2%);
    border-top: var(--border-glass);
    padding-top: 5rem;
    padding-bottom: 2rem;
    color: var(--color-text-secondary);
}

.footer-container {
    display: grid;
    grid-template-columns: 1.2fr 1.8fr;
    gap: 5rem;
    margin-bottom: 4rem;
}

.footer-brand {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.footer-desc {
    font-size: 0.9rem;
    line-height: 1.6;
}

.footer-links-group {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.footer-links-col {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.footer-col-title {
    font-family: var(--font-display);
    font-size: 1rem;
    font-weight: 600;
    color: var(--color-text-primary);
    margin-bottom: 0.5rem;
}

.footer-links-col a {
    font-size: 0.9rem;
}

.footer-links-col a:hover {
    color: var(--color-primary);
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    padding-top: 2rem;
}

.footer-bottom-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.8rem;
    color: var(--color-text-muted);
}

.footer-socials {
    display: flex;
    gap: 1.5rem;
}

/* 14. Simulated Modal */


/* 15. Keyframes & Animations */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes scaleIn {
    from { opacity: 0; transform: scale(0.9); }
    to { opacity: 1; transform: scale(1); }
}

.blinking-red {
    animation: blink 2s infinite;
}

@keyframes blink {
    0%, 100% { opacity: 1; box-shadow: 0 0 5px var(--color-accent-red); }
    50% { opacity: 0.4; box-shadow: none; }
}

/* 16. Responsive Queries (Breakpoints) */
@media (max-width: 1024px) {
    .hero-title {
        font-size: 3rem;
    }
    
    .panel-grid, .calc-grid, .splits-card, .join-promo-card {
        grid-template-columns: 1fr;
        gap: 3rem;
    }

    .splits-card {
        padding: 0;
    }

    .splits-inputs-panel {
        border-right: none;
        border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    }
}

@media (max-width: 768px) {
    section {
        padding: 4rem 0;
    }

    .nav-links {
        display: none; /* Mobile menu toggled via JS */
        position: absolute;
        top: var(--header-height);
        left: 0;
        width: 100%;
        background-color: var(--color-bg-deep);
        border-bottom: var(--border-glass);
        flex-direction: column;
        padding: 2rem 1.5rem;
        gap: 1.5rem;
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.8);
    }

    .nav-links.active {
        display: flex;
    }

    .mobile-menu-toggle {
        display: flex;
    }

    .hero-title {
        font-size: 2.5rem;
    }

    .tabs-list {
        grid-template-columns: 1fr 1fr;
    }

    .features-grid {
        grid-template-columns: 1fr;
    }

    .form-grid {
        grid-template-columns: 1fr;
    }

    .form-full {
        grid-column: span 1;
    }

    .footer-container {
        grid-template-columns: 1fr;
        gap: 3rem;
    }

    .footer-links-group {
        grid-template-columns: 1fr 1fr;
    }
}