/**
 * Revend Theme - Main Stylesheet
 *
 * @package Revend_Theme
 * @version 1.0.0
 */

/* ==========================================================================
   CSS Variables
   ========================================================================== */
:root {
    --color-primary: #2563eb;
    --color-primary-dark: #1d4ed8;
    --color-primary-light: #60a5fa;
    --color-secondary: #0f172a;
    --color-text: #1a1a1a;
    --color-text-light: #475569;
    --color-text-muted: #64748b;
    --color-text-slate: #94a3b8;
    --color-background: #ffffff;
    --color-background-light: #f8fafc;
    --color-background-blue: #f0f9ff;
    --color-border: #e2e8f0;
    --color-border-light: #cbd5e1;
    --color-error: #ef4444;
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --border-radius: 12px;
    --border-radius-lg: 16px;
    --border-radius-xl: 20px;
    --border-radius-2xl: 24px;
    --shadow-sm: 0 4px 12px rgba(37, 99, 235, 0.2);
    --shadow-md: 0 8px 24px rgba(37, 99, 235, 0.35);
    --shadow-lg: 0 20px 60px rgba(0, 0, 0, 0.12);
    --transition: all 0.3s ease;
}

/* ==========================================================================
   Reset & Base Styles
   ========================================================================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    line-height: 1.7;
    color: var(--color-text);
    background: var(--color-background);
}

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

img {
    max-width: 100%;
    height: auto;
}

ul, ol {
    list-style: none;
}

/* ==========================================================================
   Layout
   ========================================================================== */
.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 24px;
}

/* ==========================================================================
   Header
   ========================================================================== */
.site-header {
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(10px);
    padding: 20px 0;
    position: sticky;
    top: 0;
    z-index: 100;
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
}

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

.logo {
    display: block;
    text-decoration: none;
}

.logo img,
.custom-logo {
    height: 42px;
    width: auto;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 40px;
}

.nav-link {
    font-size: 15px;
    color: var(--color-text);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s ease;
}

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

.phone {
    font-size: 16px;
    color: var(--color-text);
    text-decoration: none;
    font-weight: 500;
    padding: 12px 24px;
    background: #f5f5f5;
    border-radius: var(--border-radius);
    transition: var(--transition);
}

.phone:hover {
    background: #e8f6ff;
    color: var(--color-primary);
}

.phone-icon {
    margin-right: 4px;
}

/* ==========================================================================
   Buttons
   ========================================================================== */
.cta-button {
    display: inline-block;
    background: var(--color-primary);
    color: var(--color-background);
    padding: 16px 40px;
    font-size: 17px;
    font-weight: 600;
    text-decoration: none;
    border-radius: var(--border-radius);
    transition: var(--transition);
    box-shadow: var(--shadow-sm);
    cursor: pointer;
    border: none;
}

.cta-button:hover {
    background: var(--color-primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.cta-button-white {
    display: inline-block;
    background: var(--color-background);
    color: var(--color-primary);
    padding: 16px 40px;
    font-size: 17px;
    font-weight: 600;
    text-decoration: none;
    border-radius: var(--border-radius);
    transition: var(--transition);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    cursor: pointer;
    border: none;
}

.cta-button-white:hover {
    background: var(--color-background-blue);
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.2);
}

/* ==========================================================================
   Hero Section
   ========================================================================== */
.hero {
    background: linear-gradient(180deg, var(--color-background-blue) 0%, var(--color-background) 100%);
    padding: 80px 0;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(37, 99, 235, 0.2), transparent);
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
}

.hero-text {
    text-align: left;
}

.hero h1 {
    font-size: 56px;
    font-weight: 700;
    margin-bottom: 24px;
    line-height: 1.1;
    color: var(--color-secondary);
    letter-spacing: -0.02em;
}

.hero p {
    font-size: 21px;
    margin-bottom: 40px;
    color: var(--color-text-light);
    font-weight: 400;
}

.hero-image-container {
    position: relative;
}

.hero-img {
    width: 100%;
    height: auto;
    border-radius: var(--border-radius-2xl);
    box-shadow: var(--shadow-lg);
    transition: all 0.5s ease;
}

.hero-img:hover {
    transform: translateY(-8px) scale(1.02);
    box-shadow: 0 30px 80px rgba(0, 0, 0, 0.18);
}

/* ==========================================================================
   Section Transition
   ========================================================================== */
.section-transition {
    padding: 60px 0;
    background: linear-gradient(180deg, var(--color-background) 0%, var(--color-background-blue) 100%);
    text-align: center;
}

.transition-image {
    max-width: 200px;
    height: auto;
    margin: 0 auto;
    display: block;
    animation: float 3s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0px); }
    50% { transform: translateY(-12px); }
}

/* ==========================================================================
   Problem Section
   ========================================================================== */
.problem {
    padding: 100px 0;
    background: var(--color-background);
    position: relative;
}

.problem::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 80%;
    max-width: 600px;
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(0, 0, 0, 0.06), transparent);
}

.problem h2 {
    font-size: 42px;
    font-weight: 700;
    text-align: center;
    margin-bottom: 64px;
    color: var(--color-secondary);
    letter-spacing: -0.02em;
}

.problem-points {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 32px;
    margin-bottom: 40px;
}

.problem-point {
    background: var(--color-background-light);
    padding: 40px;
    border-radius: var(--border-radius-lg);
    border: 1px solid var(--color-border);
    transition: var(--transition);
}

.problem-point:hover {
    border-color: var(--color-border-light);
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.04);
}

.problem-point h3 {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--color-error);
}

.problem-point p {
    color: var(--color-text-muted);
    font-size: 16px;
    line-height: 1.6;
}

/* ==========================================================================
   Solution Section
   ========================================================================== */
.solution {
    padding: 100px 0;
    background: linear-gradient(180deg, var(--color-background) 0%, var(--color-background-blue) 100%);
}

.solution h2 {
    font-size: 42px;
    font-weight: 700;
    text-align: center;
    margin-bottom: 24px;
    color: var(--color-secondary);
    letter-spacing: -0.02em;
}

.solution-intro {
    text-align: center;
    font-size: 19px;
    margin-bottom: 64px;
    max-width: 720px;
    margin-left: auto;
    margin-right: auto;
    color: var(--color-text-light);
}

.benefits {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 24px;
}

.benefit {
    padding: 40px;
    background: var(--color-background);
    border-radius: var(--border-radius-lg);
    border: 1px solid var(--color-border);
    transition: var(--transition);
}

.benefit:hover {
    border-color: var(--color-primary);
    box-shadow: 0 8px 24px rgba(37, 99, 235, 0.08);
    transform: translateY(-4px);
}

.benefit h3 {
    font-size: 19px;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--color-secondary);
}

.benefit p {
    color: var(--color-text-muted);
    font-size: 15px;
    line-height: 1.6;
}

/* ==========================================================================
   Technology Section
   ========================================================================== */
.technology {
    padding: 100px 0;
    background: var(--color-background);
}

.technology h2 {
    font-size: 42px;
    font-weight: 700;
    text-align: center;
    margin-bottom: 24px;
    color: var(--color-secondary);
    letter-spacing: -0.02em;
}

.technology-intro {
    text-align: center;
    font-size: 19px;
    margin-bottom: 64px;
    max-width: 720px;
    margin-left: auto;
    margin-right: auto;
    color: var(--color-text-light);
}

.battery-models {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 40px;
    max-width: 1100px;
    margin: 0 auto;
}

.battery-card {
    background: var(--color-background-light);
    border-radius: var(--border-radius-xl);
    padding: 48px 32px;
    text-align: center;
    border: 1px solid var(--color-border);
    transition: var(--transition);
    overflow: hidden;
}

.battery-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 12px 32px rgba(37, 99, 235, 0.12);
    border-color: var(--color-primary);
}

.battery-image {
    width: 100%;
    max-width: 280px;
    height: 280px;
    object-fit: cover;
    object-position: center bottom;
    margin: 0 auto 32px;
    display: block;
    border-radius: var(--border-radius-lg);
}

.battery-card:first-child .battery-image {
    object-position: center 25%;
}

.battery-card h3 {
    font-size: 24px;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--color-secondary);
}

.battery-card p {
    color: var(--color-text-muted);
    font-size: 15px;
    line-height: 1.6;
    margin-bottom: 24px;
}

.battery-specs {
    display: flex;
    justify-content: center;
    gap: 24px;
    margin-top: 20px;
}

.spec {
    text-align: center;
}

.spec-value {
    font-size: 20px;
    font-weight: 700;
    color: var(--color-primary);
    display: block;
    margin-bottom: 4px;
}

.spec-label {
    font-size: 13px;
    color: var(--color-text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

/* ==========================================================================
   VPA Program Section
   ========================================================================== */
.vpa-program {
    padding: 100px 0;
    background: linear-gradient(135deg, #1e3a8a 0%, #3b82f6 100%);
    color: white;
    position: relative;
    overflow: hidden;
}

.vpa-program::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image:
        radial-gradient(circle at 20% 20%, rgba(255, 255, 255, 0.03) 1px, transparent 1px),
        radial-gradient(circle at 80% 80%, rgba(255, 255, 255, 0.03) 1px, transparent 1px);
    background-size: 50px 50px;
    pointer-events: none;
    opacity: 0.5;
}

.vpa-program::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(circle at 80% 50%, rgba(30, 58, 138, 0.8) 0%, transparent 60%);
    pointer-events: none;
}

.vpa-program .container {
    position: relative;
    z-index: 1;
}

.vpa-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
    margin-bottom: 64px;
}

.vpa-text h2 {
    font-size: 42px;
    font-weight: 700;
    margin-bottom: 24px;
    letter-spacing: -0.02em;
}

.vpa-text p {
    font-size: 18px;
    margin-bottom: 24px;
    opacity: 0.95;
    line-height: 1.7;
}

.vpa-image-container {
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 40px;
    background: rgba(255, 255, 255, 0.05);
    border-radius: var(--border-radius-2xl);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.vpa-battery-image {
    width: 100%;
    max-width: 380px;
    height: auto;
    filter: drop-shadow(0 20px 60px rgba(0, 0, 0, 0.4));
    border-radius: var(--border-radius-lg);
    transition: all 0.4s ease;
}

.vpa-battery-image:hover {
    transform: translateY(-4px);
    filter: drop-shadow(0 30px 80px rgba(0, 0, 0, 0.5));
}

.vpa-highlights {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 24px;
}

.vpa-highlight {
    text-align: center;
    padding: 32px 24px;
    background: rgba(255, 255, 255, 0.08);
    border-radius: var(--border-radius-lg);
    border: 1px solid rgba(255, 255, 255, 0.12);
    backdrop-filter: blur(10px);
    transition: var(--transition);
}

.vpa-highlight:hover {
    background: rgba(255, 255, 255, 0.12);
    transform: translateY(-4px);
}

.vpa-highlight h3 {
    font-size: 48px;
    font-weight: 700;
    margin-bottom: 8px;
    color: #93c5fd;
    letter-spacing: -0.02em;
}

.vpa-highlight p {
    font-size: 16px;
    opacity: 0.9;
    margin-bottom: 0;
}

/* ==========================================================================
   How It Works Section
   ========================================================================== */
.how-it-works {
    padding: 100px 0;
    background: var(--color-background);
}

.how-it-works h2 {
    font-size: 42px;
    font-weight: 700;
    text-align: center;
    margin-bottom: 64px;
    color: var(--color-secondary);
    letter-spacing: -0.02em;
}

.steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 40px;
    max-width: 1000px;
    margin: 0 auto;
}

.step {
    text-align: center;
    padding: 24px;
}

.step-number {
    width: 64px;
    height: 64px;
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-light) 100%);
    color: white;
    border-radius: var(--border-radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 28px;
    font-weight: 700;
    margin: 0 auto 24px;
    box-shadow: var(--shadow-sm);
}

.step h3 {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--color-secondary);
}

.step p {
    color: var(--color-text-muted);
    font-size: 15px;
    line-height: 1.6;
}

/* ==========================================================================
   Final CTA Section
   ========================================================================== */
.final-cta {
    padding: 100px 0;
    background: linear-gradient(180deg, var(--color-background-light) 0%, var(--color-background) 100%);
    text-align: center;
    position: relative;
}

.final-cta::before {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 80%;
    max-width: 600px;
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(0, 0, 0, 0.06), transparent);
}

.final-cta h2 {
    font-size: 42px;
    font-weight: 700;
    margin-bottom: 20px;
    color: var(--color-secondary);
    letter-spacing: -0.02em;
}

.final-cta p {
    font-size: 19px;
    margin-bottom: 32px;
    color: var(--color-text-light);
}

.final-cta p:last-of-type {
    font-size: 15px;
    color: var(--color-text-muted);
}

/* ==========================================================================
   Footer
   ========================================================================== */
.site-footer {
    background: var(--color-secondary);
    color: white;
    padding: 64px 0 32px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 48px;
    margin-bottom: 48px;
}

.footer-section h3 {
    margin-bottom: 20px;
    color: var(--color-primary-light);
    font-size: 16px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.footer-section p,
.footer-section a {
    color: var(--color-text-slate);
    text-decoration: none;
    display: block;
    margin-bottom: 12px;
    font-size: 15px;
    transition: color 0.2s ease;
}

.footer-section a:hover {
    color: var(--color-primary-light);
}

.footer-bottom {
    text-align: center;
    padding-top: 32px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--color-text-muted);
    font-size: 14px;
}

.footer-bottom a {
    color: var(--color-text-muted);
    text-decoration: none;
}

.footer-bottom a:hover {
    color: var(--color-primary-light);
}

/* ==========================================================================
   Page Templates (Privacy & Terms)
   ========================================================================== */
.page-container {
    max-width: 800px;
    margin: 0 auto;
    padding: 60px 24px;
}

.page-container h1 {
    font-size: 36px;
    color: var(--color-secondary);
    margin-bottom: 32px;
    letter-spacing: -0.02em;
}

.page-container h2 {
    font-size: 22px;
    color: var(--color-primary);
    margin-top: 32px;
    margin-bottom: 16px;
    font-weight: 600;
}

.page-container p {
    margin-bottom: 16px;
    color: var(--color-text-light);
}

.page-container ul {
    margin-left: 20px;
    margin-bottom: 24px;
    list-style: disc;
}

.page-container li {
    margin-bottom: 12px;
    color: var(--color-text-light);
}

.page-container a {
    color: var(--color-primary);
}

.page-container a:hover {
    text-decoration: underline;
}

.last-updated {
    color: var(--color-text-muted);
    font-size: 14px;
    margin-bottom: 24px;
}

.compliance-box {
    background: var(--color-background-blue);
    border-left: 4px solid var(--color-primary);
    padding: 24px;
    margin: 32px 0;
    border-radius: 8px;
    font-weight: 500;
}

.back-link {
    display: inline-block;
    margin-top: 40px;
    color: var(--color-primary);
    text-decoration: none;
    font-weight: 500;
}

.back-link:hover {
    text-decoration: underline;
}

/* ==========================================================================
   Emoji Styling
   ========================================================================== */
.emoji {
    font-style: normal;
}

/* ==========================================================================
   WordPress Specific
   ========================================================================== */
.site-main {
    padding: 60px 0;
}

.entry-header {
    margin-bottom: 32px;
}

.entry-title {
    font-size: 36px;
    color: var(--color-secondary);
    letter-spacing: -0.02em;
}

.entry-content p {
    margin-bottom: 16px;
    color: var(--color-text-light);
}

/* ==========================================================================
   404 Error Page
   ========================================================================== */
.error-404 {
    padding: 100px 0;
    background: linear-gradient(180deg, var(--color-background-blue) 0%, var(--color-background) 100%);
    min-height: 60vh;
    display: flex;
    align-items: center;
}

.error-content {
    text-align: center;
    max-width: 600px;
    margin: 0 auto;
}

.error-code {
    font-size: 120px;
    font-weight: 700;
    color: var(--color-primary);
    line-height: 1;
    margin-bottom: 16px;
    letter-spacing: -0.02em;
}

.error-content h2 {
    font-size: 36px;
    font-weight: 700;
    color: var(--color-secondary);
    margin-bottom: 16px;
    letter-spacing: -0.02em;
}

.error-content > p {
    font-size: 18px;
    color: var(--color-text-light);
    margin-bottom: 40px;
}

.error-actions {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 48px;
}

.cta-button-outline {
    display: inline-block;
    background: transparent;
    color: var(--color-primary);
    padding: 16px 40px;
    font-size: 17px;
    font-weight: 600;
    text-decoration: none;
    border-radius: var(--border-radius);
    transition: var(--transition);
    border: 2px solid var(--color-primary);
    cursor: pointer;
}

.cta-button-outline:hover {
    background: var(--color-primary);
    color: var(--color-background);
    transform: translateY(-2px);
}

.error-help {
    background: var(--color-background);
    padding: 32px;
    border-radius: var(--border-radius-lg);
    border: 1px solid var(--color-border);
}

.error-help p {
    font-size: 16px;
    font-weight: 600;
    color: var(--color-secondary);
    margin-bottom: 16px;
}

.error-help ul {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 8px 24px;
    list-style: none;
    margin: 0;
    padding: 0;
}

.error-help li a {
    color: var(--color-primary);
    font-size: 15px;
    font-weight: 500;
}

.error-help li a:hover {
    text-decoration: underline;
}

@media (max-width: 768px) {
    .error-code {
        font-size: 80px;
    }

    .error-content h2 {
        font-size: 28px;
    }

    .error-actions {
        flex-direction: column;
        align-items: center;
    }

    .error-help ul {
        flex-direction: column;
        gap: 12px;
    }
}

/* ==========================================================================
   Responsive Design
   ========================================================================== */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
    }

    .phone {
        font-size: 15px;
        padding: 12px 20px;
        font-weight: 600;
    }

    .logo img,
    .custom-logo {
        height: 36px;
    }

    .hero {
        padding: 60px 0;
    }

    .hero-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .hero-text {
        text-align: center;
    }

    .hero h1 {
        font-size: 36px;
    }

    .hero p {
        font-size: 18px;
    }

    .problem h2,
    .solution h2,
    .technology h2,
    .vpa-text h2,
    .how-it-works h2,
    .final-cta h2 {
        font-size: 32px;
    }

    .problem,
    .solution,
    .technology,
    .vpa-program,
    .how-it-works,
    .final-cta {
        padding: 60px 0;
    }

    .phone {
        font-size: 14px;
        padding: 10px 18px;
    }

    .vpa-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .vpa-image-container {
        order: -1;
    }

    .battery-models {
        grid-template-columns: 1fr;
    }

    .page-container {
        padding: 40px 20px;
    }

    .page-container h1 {
        font-size: 28px;
    }

    .page-container h2 {
        font-size: 20px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 16px;
    }

    .hero h1 {
        font-size: 28px;
    }

    .cta-button,
    .cta-button-white {
        padding: 14px 28px;
        font-size: 16px;
    }

    .vpa-highlight h3 {
        font-size: 36px;
    }

    .problem-points,
    .benefits {
        grid-template-columns: 1fr;
    }
}