/* Shared Variables & Reset */
:root {
    --primary: #0ea5e9;
    --primary-dark: #0284c7;
    --secondary: #6366f1;
    --accent: #06b6d4;
    --dark-bg: #0f172a;
    --section-bg: #1e293b;
    --card-bg: rgba(30, 41, 59, 0.6);
    --text-light: #f8fafc;
    --text-dim: #cbd5e1;
    --text-gray: #94a3b8;
    --gradient-main: linear-gradient(135deg, #0ea5e9 0%, #6366f1 100%);
    --glass: rgba(15, 23, 42, 0.85);
    --glass-border: rgba(255, 255, 255, 0.08);
    --container-width: 1200px;
}

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

body {
    font-family: 'Inter', 'Noto Sans TC', sans-serif;
    background-color: var(--dark-bg);
    color: var(--text-light);
    line-height: 1.7;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

a {
    text-decoration: none;
    color: inherit;
    transition: all 0.3s ease;
}

ul {
    list-style: none;
}

/* Layout Utilities */
.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 2rem;
}

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

.section-title {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 3rem;
    position: relative;
    display: inline-block;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 4px;
    background: var(--gradient-main);
    border-radius: 2px;
}

/* Header */
header {
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    padding: 1rem 0;
    background: var(--glass);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--glass-border);
}

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

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: 0.1em;
    background: var(--gradient-main);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo::before {
    content: '';
    display: block;
    width: 28px;
    height: 28px;
    background: var(--gradient-main);
    border-radius: 6px;
    transform: rotate(45deg);
}

nav ul {
    display: flex;
    gap: 2.5rem;
}

nav a {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-dim);
    position: relative;
}

nav a:hover,
nav a.active {
    color: var(--text-light);
}

nav a.active::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 100%;
    height: 2px;
    background: var(--primary);
    box-shadow: 0 0 10px var(--primary);
}

/* Page Hero */
.page-hero {
    padding: 160px 0 60px;
    background: radial-gradient(circle at 50% 0%, rgba(14, 165, 233, 0.15), transparent 60%);
    text-align: center;
    margin-bottom: 4rem;
}

.page-hero h1 {
    font-size: 3.5rem;
    margin-bottom: 1rem;
    font-weight: 800;
    letter-spacing: -0.02em;
}

/* Contact Info Box */
.contact-info-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    margin-bottom: 6rem;
}

.info-card {
    background: var(--card-bg);
    border: 1px solid var(--glass-border);
    padding: 2.5rem;
    border-radius: 20px;
    text-align: center;
    transition: transform 0.3s ease, border-color 0.3s ease;
}

.info-card:hover {
    transform: translateY(-5px);
    border-color: var(--primary);
}

.info-icon {
    width: 60px;
    height: 60px;
    background: rgba(14, 165, 233, 0.1);
    color: var(--primary);
    border-radius: 15px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.5rem;
    font-size: 1.5rem;
}

.info-card h3 {
    margin-bottom: 1rem;
    font-size: 1.25rem;
}

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

/* Support Process */
.process-section {
    background: var(--section-bg);
    padding: 6rem 0;
    margin: 4rem 0;
}

.process-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 1.5rem;
    position: relative;
}

.process-step {
    text-align: center;
    position: relative;
    z-index: 1;
}

.step-number {
    width: 50px;
    height: 50px;
    background: var(--gradient-main);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    margin: 0 auto 1.5rem;
    font-size: 1.2rem;
    box-shadow: 0 0 20px rgba(14, 165, 233, 0.4);
}

.process-step h4 {
    margin-bottom: 0.75rem;
    font-size: 1.1rem;
}

.process-step p {
    font-size: 0.9rem;
    color: var(--text-gray);
}

/* FAQ Section */
.faq-section {
    max-width: 850px;
    margin: 0 auto 6rem;
}

details {
    background: rgba(30, 41, 59, 0.3);
    border: 1px solid var(--glass-border);
    border-radius: 16px;
    margin-bottom: 1.25rem;
    overflow: hidden;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

details:hover {
    border-color: rgba(14, 165, 233, 0.4);
    background: rgba(30, 41, 59, 0.5);
    transform: translateY(-2px);
}

details[open] {
    border-color: var(--primary);
    background: rgba(15, 23, 42, 0.8);
    box-shadow: 0 20px 40px -20px rgba(0, 0, 0, 0.5);
}

summary {
    padding: 1.5rem 2rem;
    cursor: pointer;
    font-weight: 700;
    font-size: 1.1rem;
    list-style: none;
    display: flex;
    justify-content: space-between;
    align-items: center;
    user-select: none;
    transition: color 0.3s ease;
}

/* Hide default marker in all browsers */
summary::-webkit-details-marker {
    display: none;
}

summary {
    list-style: none;
}

summary::after {
    content: '';
    width: 8px;
    height: 8px;
    border-right: 2px solid var(--primary);
    border-bottom: 2px solid var(--primary);
    transform: rotate(45deg);
    transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    margin-right: 0.25rem;
}

details[open] summary {
    color: var(--primary);
    padding-bottom: 1rem;
}

details[open] summary::after {
    transform: rotate(-135deg);
}

.faq-content {
    padding: 0 2rem 2rem;
    color: var(--text-dim);
    line-height: 1.8;
    border-top: 1px solid var(--glass-border);
    padding-top: 1.5rem;
    animation: fadeInSlide 0.4s ease-out;
}

@keyframes fadeInSlide {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* RMA Section */
.rma-box {
    background: linear-gradient(rgba(30, 41, 59, 0.4), rgba(30, 41, 59, 0.4)), url('https://images.unsplash.com/photo-1581091226825-a6a2a5aee158?auto=format&fit=crop&q=80&w=2070');
    background-size: cover;
    background-position: center;
    border-radius: 24px;
    padding: 4rem;
    margin-bottom: 6rem;
    border: 1px solid var(--glass-border);
    position: relative;
    overflow: hidden;
}

.rma-box::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(15, 23, 42, 0.8);
    z-index: 0;
}

.rma-content {
    position: relative;
    z-index: 1;
}

.rma-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    margin-top: 2rem;
}

.rma-list li {
    margin-bottom: 1rem;
    padding-left: 1.5rem;
    position: relative;
    color: var(--text-dim);
}

.rma-list li::before {
    content: '•';
    color: var(--accent);
    position: absolute;
    left: 0;
    font-weight: bold;
}

/* Footer */
footer {
    background: #020617;
    padding: 5rem 0 2rem;
    border-top: 1px solid var(--glass-border);
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1.5fr;
    gap: 3rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    padding-bottom: 3rem;
    margin-bottom: 2rem;
}

.footer-col h4 {
    color: var(--text-light);
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
}

.contact-list li {
    margin-bottom: 1rem;
    color: var(--text-gray);
    display: flex;
    gap: 12px;
    align-items: flex-start;
}

.copyright {
    text-align: center;
    color: #475569;
    font-size: 0.875rem;
}

/* Responsive */
@media (max-width: 1024px) {
    .process-grid {
        grid-template-columns: repeat(3, 1fr);
        gap: 2rem;
    }

    .contact-info-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .nav-container {
        flex-direction: column;
        gap: 1rem;
    }

    nav ul {
        flex-wrap: wrap;
        justify-content: center;
        gap: 1.5rem;
    }

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

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

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