/* ============================================
   RentPartyHub Landing Page — Design System
   ============================================ */

/* === CSS Variables === */
:root {
    --color-bg: #0a0a0f;
    --color-bg-elevated: #12121a;
    --color-bg-card: #1a1a26;
    --color-bg-card-hover: #22223a;
    --color-surface: #2a2a3e;

    --color-text: #f0f0f5;
    --color-text-secondary: #a0a0b8;
    --color-text-muted: #6b6b82;

    --color-primary: #8b5cf6;
    --color-primary-light: #a78bfa;
    --color-primary-dark: #7c3aed;

    --color-accent: #f472b6;
    --color-accent-light: #f9a8d4;

    --gradient-primary: linear-gradient(135deg, #8b5cf6, #ec4899);
    --gradient-hero: linear-gradient(135deg, #8b5cf6 0%, #6366f1 50%, #ec4899 100%);
    --gradient-card: linear-gradient(180deg, rgba(139, 92, 246, 0.08), transparent);

    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 24px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 8px 40px rgba(0, 0, 0, 0.5);
    --shadow-glow: 0 0 40px rgba(139, 92, 246, 0.15);

    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-xl: 28px;

    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --font: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
}

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

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

a {
    text-decoration: none;
    color: inherit;
}

img {
    max-width: 100%;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* === Navigation === */
#navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(10, 10, 15, 0.8);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    transition: var(--transition);
}

#navbar.scrolled {
    background: rgba(10, 10, 15, 0.95);
    box-shadow: var(--shadow-md);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    font-size: 1.25rem;
}

.logo-icon {
    font-size: 1.5rem;
}

.logo-text {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 32px;
}

.nav-links a {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--color-text-secondary);
    transition: var(--transition);
    position: relative;
}

.nav-links a:hover {
    color: var(--color-text);
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-primary);
    transition: var(--transition);
    border-radius: 2px;
}

.nav-links a:hover::after {
    width: 100%;
}

.lang-btn {
    display: flex;
    align-items: center;
    gap: 6px;
    background: var(--color-surface);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--color-text);
    padding: 6px 14px;
    border-radius: 100px;
    font-size: 0.85rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    font-family: var(--font);
}

.lang-btn:hover {
    background: var(--color-bg-card-hover);
    border-color: var(--color-primary);
}

.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}

.mobile-menu-btn span {
    width: 24px;
    height: 2px;
    background: var(--color-text);
    border-radius: 2px;
    transition: var(--transition);
}

/* === Buttons === */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 14px 28px;
    border-radius: var(--radius-md);
    font-weight: 600;
    font-size: 0.95rem;
    border: none;
    cursor: pointer;
    transition: var(--transition);
    font-family: var(--font);
    white-space: nowrap;
}

.btn-primary {
    background: var(--gradient-primary);
    color: white;
    box-shadow: 0 4px 20px rgba(139, 92, 246, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 30px rgba(139, 92, 246, 0.45);
}

.btn-outline {
    background: transparent;
    color: var(--color-text);
    border: 1px solid rgba(255, 255, 255, 0.15);
}

.btn-outline:hover {
    background: rgba(255, 255, 255, 0.05);
    border-color: var(--color-primary);
}

.btn-block {
    width: 100%;
}

/* === Hero Section === */
#hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: 72px;
    overflow: hidden;
}

.hero-bg-shapes {
    position: absolute;
    inset: 0;
    pointer-events: none;
}

.shape {
    position: absolute;
    border-radius: 50%;
    filter: blur(120px);
    opacity: 0.15;
}

.shape-1 {
    width: 600px;
    height: 600px;
    background: var(--color-primary);
    top: -200px;
    right: -100px;
    animation: float 20s ease-in-out infinite;
}

.shape-2 {
    width: 500px;
    height: 500px;
    background: var(--color-accent);
    bottom: -150px;
    left: -100px;
    animation: float 25s ease-in-out infinite reverse;
}

.shape-3 {
    width: 300px;
    height: 300px;
    background: #6366f1;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    animation: pulse 15s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0); }
    25% { transform: translate(30px, -40px); }
    50% { transform: translate(-20px, 30px); }
    75% { transform: translate(40px, 20px); }
}

@keyframes pulse {
    0%, 100% { opacity: 0.1; transform: translate(-50%, -50%) scale(1); }
    50% { opacity: 0.2; transform: translate(-50%, -50%) scale(1.3); }
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
    padding: 60px 0;
}

.hero-badge {
    display: inline-block;
    padding: 8px 20px;
    background: rgba(139, 92, 246, 0.12);
    border: 1px solid rgba(139, 92, 246, 0.25);
    border-radius: 100px;
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--color-primary-light);
    margin-bottom: 28px;
    animation: fadeInUp 0.6s ease-out;
}

#hero h1 {
    font-size: clamp(2.5rem, 6vw, 4rem);
    font-weight: 900;
    line-height: 1.1;
    margin-bottom: 24px;
    animation: fadeInUp 0.6s ease-out 0.1s both;
}

#hero h1 span {
    display: block;
}

.gradient-text {
    background: var(--gradient-hero);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.15rem;
    color: var(--color-text-secondary);
    max-width: 620px;
    margin: 0 auto 36px;
    line-height: 1.7;
    animation: fadeInUp 0.6s ease-out 0.2s both;
}

.hero-cta {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 56px;
    animation: fadeInUp 0.6s ease-out 0.3s both;
}

.hero-stats {
    display: flex;
    gap: 40px;
    justify-content: center;
    flex-wrap: wrap;
    animation: fadeInUp 0.6s ease-out 0.4s both;
}

.stat {
    display: flex;
    align-items: center;
    gap: 12px;
}

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

.stat div {
    text-align: left;
}

.stat strong {
    display: block;
    font-size: 0.9rem;
    font-weight: 700;
}

.stat span {
    font-size: 0.8rem;
    color: var(--color-text-muted);
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(24px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* === Section Styles === */
section {
    padding: 100px 0;
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-tag {
    display: inline-block;
    padding: 6px 16px;
    background: rgba(139, 92, 246, 0.1);
    border: 1px solid rgba(139, 92, 246, 0.2);
    border-radius: 100px;
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--color-primary-light);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 16px;
}

.section-header h2 {
    font-size: clamp(1.8rem, 4vw, 2.5rem);
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 12px;
}

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

/* === Tabs === */
.tabs {
    display: flex;
    justify-content: center;
    gap: 8px;
    margin-bottom: 48px;
}

.tab {
    padding: 12px 28px;
    border-radius: var(--radius-md);
    border: 1px solid rgba(255, 255, 255, 0.1);
    background: transparent;
    color: var(--color-text-secondary);
    font-weight: 600;
    font-size: 0.95rem;
    cursor: pointer;
    transition: var(--transition);
    font-family: var(--font);
}

.tab:hover {
    background: rgba(255, 255, 255, 0.05);
}

.tab.active {
    background: var(--gradient-primary);
    color: white;
    border-color: transparent;
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
    animation: fadeInUp 0.4s ease-out;
}

/* === Steps === */
.steps-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.step-card {
    background: var(--color-bg-card);
    border: 1px solid rgba(255, 255, 255, 0.06);
    border-radius: var(--radius-lg);
    padding: 36px 28px;
    position: relative;
    overflow: hidden;
    transition: var(--transition);
}

.step-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--gradient-primary);
    opacity: 0;
    transition: var(--transition);
}

.step-card:hover {
    transform: translateY(-4px);
    border-color: rgba(139, 92, 246, 0.2);
    box-shadow: var(--shadow-glow);
}

.step-card:hover::before {
    opacity: 1;
}

.step-number {
    font-size: 0.75rem;
    font-weight: 700;
    color: var(--color-primary);
    margin-bottom: 16px;
    letter-spacing: 2px;
}

.step-icon {
    font-size: 2.5rem;
    margin-bottom: 16px;
}

.step-card h3 {
    font-size: 1.15rem;
    font-weight: 700;
    margin-bottom: 10px;
}

.step-card p {
    color: var(--color-text-secondary);
    font-size: 0.92rem;
    line-height: 1.6;
}

/* === Features === */
#features {
    background: var(--color-bg-elevated);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.feature-card {
    background: var(--color-bg-card);
    border: 1px solid rgba(255, 255, 255, 0.06);
    border-radius: var(--radius-lg);
    padding: 32px 24px;
    text-align: center;
    transition: var(--transition);
}

.feature-card:hover {
    transform: translateY(-4px);
    border-color: rgba(139, 92, 246, 0.15);
    box-shadow: var(--shadow-glow);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: 16px;
    display: block;
}

.feature-card h3 {
    font-size: 1.1rem;
    font-weight: 700;
    margin-bottom: 8px;
}

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

/* === Plans === */
.plans-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    align-items: start;
}

.plan-card {
    background: var(--color-bg-card);
    border: 1px solid rgba(255, 255, 255, 0.06);
    border-radius: var(--radius-lg);
    padding: 36px 28px;
    position: relative;
    transition: var(--transition);
}

.plan-card:hover {
    transform: translateY(-4px);
    border-color: rgba(139, 92, 246, 0.15);
}

.plan-featured {
    border-color: var(--color-primary);
    background: linear-gradient(180deg, rgba(139, 92, 246, 0.08), var(--color-bg-card));
    box-shadow: 0 0 40px rgba(139, 92, 246, 0.1);
}

.plan-badge {
    position: absolute;
    top: -12px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--gradient-primary);
    color: white;
    padding: 6px 20px;
    border-radius: 100px;
    font-size: 0.8rem;
    font-weight: 700;
    white-space: nowrap;
}

.plan-header {
    text-align: center;
    margin-bottom: 28px;
    padding-bottom: 28px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.plan-header h3 {
    font-size: 1.3rem;
    font-weight: 700;
    margin-bottom: 12px;
}

.plan-price .price {
    font-size: 2.2rem;
    font-weight: 900;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.plan-price .period {
    color: var(--color-text-muted);
    font-size: 0.95rem;
}

.plan-desc {
    color: var(--color-text-muted);
    font-size: 0.85rem;
    margin-top: 8px;
}

.plan-features {
    list-style: none;
    margin-bottom: 28px;
}

.plan-features li {
    padding: 8px 0;
    color: var(--color-text-secondary);
    font-size: 0.92rem;
}

/* === Payments / Policy === */
#payments {
    background: var(--color-bg-elevated);
}

.policy-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

.policy-card {
    background: var(--color-bg-card);
    border: 1px solid rgba(255, 255, 255, 0.06);
    border-radius: var(--radius-lg);
    padding: 32px 28px;
}

.policy-icon {
    font-size: 2.2rem;
    margin-bottom: 16px;
}

.policy-card h3 {
    font-size: 1.15rem;
    font-weight: 700;
    margin-bottom: 16px;
}

.policy-card ul {
    list-style: none;
}

.policy-card li {
    padding: 6px 0;
    color: var(--color-text-secondary);
    font-size: 0.9rem;
    line-height: 1.6;
    position: relative;
    padding-left: 16px;
}

.policy-card li::before {
    content: '→';
    position: absolute;
    left: 0;
    color: var(--color-primary);
    font-weight: 700;
}

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

.faq-item {
    border: 1px solid rgba(255, 255, 255, 0.06);
    border-radius: var(--radius-md);
    margin-bottom: 12px;
    overflow: hidden;
    transition: var(--transition);
}

.faq-item:hover {
    border-color: rgba(139, 92, 246, 0.2);
}

.faq-question {
    width: 100%;
    padding: 20px 24px;
    background: var(--color-bg-card);
    border: none;
    color: var(--color-text);
    font-size: 1rem;
    font-weight: 600;
    text-align: left;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-family: var(--font);
    transition: var(--transition);
}

.faq-question:hover {
    background: var(--color-bg-card-hover);
}

.faq-toggle {
    font-size: 1.4rem;
    color: var(--color-primary);
    transition: var(--transition);
    flex-shrink: 0;
    margin-left: 16px;
}

.faq-item.open .faq-toggle {
    transform: rotate(45deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.faq-item.open .faq-answer {
    max-height: 300px;
}

.faq-answer p {
    padding: 0 24px 20px;
    color: var(--color-text-secondary);
    font-size: 0.92rem;
    line-height: 1.7;
}

/* === Notify CTA === */
#notify {
    padding: 80px 0;
}

.notify-card {
    background: var(--gradient-card);
    border: 1px solid rgba(139, 92, 246, 0.2);
    border-radius: var(--radius-xl);
    padding: 64px 48px;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.notify-card::before {
    content: '';
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at center, rgba(139, 92, 246, 0.08), transparent 70%);
    pointer-events: none;
}

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

.notify-content h2 {
    font-size: 2rem;
    font-weight: 800;
    margin-bottom: 12px;
}

.notify-content > p {
    color: var(--color-text-secondary);
    margin-bottom: 32px;
    font-size: 1.05rem;
}

.notify-form .form-group {
    display: flex;
    max-width: 500px;
    margin: 0 auto;
    gap: 12px;
}

.notify-form input {
    flex: 1;
    padding: 14px 20px;
    border-radius: var(--radius-md);
    border: 1px solid rgba(255, 255, 255, 0.1);
    background: var(--color-bg-card);
    color: var(--color-text);
    font-size: 0.95rem;
    font-family: var(--font);
    outline: none;
    transition: var(--transition);
}

.notify-form input:focus {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(139, 92, 246, 0.15);
}

.form-note {
    margin-top: 16px;
    font-size: 0.85rem;
    color: var(--color-text-muted);
}

/* === Footer === */
#footer {
    background: var(--color-bg-elevated);
    padding: 60px 0 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 40px;
}

.footer-brand p {
    color: var(--color-text-muted);
    font-size: 0.9rem;
    margin-top: 12px;
    line-height: 1.6;
    max-width: 300px;
}

.footer-links h4 {
    font-size: 0.85rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--color-text-secondary);
    margin-bottom: 16px;
}

.footer-links a {
    display: block;
    color: var(--color-text-muted);
    font-size: 0.9rem;
    padding: 4px 0;
    transition: var(--transition);
}

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

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    padding-top: 24px;
    text-align: center;
}

.footer-bottom p {
    color: var(--color-text-muted);
    font-size: 0.85rem;
}

/* === Responsive === */
@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: fixed;
        top: 72px;
        left: 0;
        right: 0;
        background: rgba(10, 10, 15, 0.98);
        flex-direction: column;
        padding: 24px;
        gap: 20px;
        border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    }

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

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

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

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

    .hero-stats {
        flex-direction: column;
        align-items: center;
        gap: 20px;
    }

    .footer-grid {
        grid-template-columns: 1fr;
        gap: 32px;
    }

    .notify-card {
        padding: 40px 24px;
    }

    .notify-form .form-group {
        flex-direction: column;
    }

    .hero-cta {
        flex-direction: column;
        align-items: center;
    }
}

@media (max-width: 480px) {
    #hero h1 {
        font-size: 2rem;
    }

    .section-header h2 {
        font-size: 1.5rem;
    }
}