/* ========== GLOBAL & RESET ========== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #18325c;
    --primary-dark: #18325c;
    --primary-light: #4db6ac;
    --accent-color: #ff6f00;
    --text-dark: #1e2a3e;
    --text-light: #5a6e7c;
    --bg-light: #f8fafc;
    --white: #ffffff;
    --card-bg: #ffffff;
    --shadow: 0 12px 30px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 20px 40px rgba(0, 0, 0, 0.12);
    --border-light: rgba(0, 0, 0, 0.05);
}

.dark-mode {
    --primary-color: white;
    --primary-dark: white;
    --primary-light: #4db6ac;
    --accent-color: #ff6f00;
    --text-dark: #eceff1;
    --text-light: #b0bec5;
    --bg-light: #121212;
    --white: #1e1e1e;
    --card-bg: #2d2d2d;
    --shadow: 0 12px 30px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 20px 40px rgba(0, 0, 0, 0.4);
    --border-light: rgba(255, 255, 255, 0.08);
}

body {
    font-family: 'Inter', 'Segoe UI', sans-serif;
    background-color: var(--bg-light);
    color: var(--text-dark);
    line-height: 1.5;
    transition: background-color 0.3s ease, color 0.2s ease;
}

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

/* ========== DARK MODE TOGGLE BUTTON ========== */
.dark-mode-toggle {
    position: fixed !important;
    top: 24px !important;
    right: 24px !important;
    z-index: 9999 !important;

    display: flex;
    align-items: center;
    gap: 8px;

    background: rgba(255, 255, 255, 0.9);
    color: var(--text-dark);

    border: 1px solid var(--border-light);
    border-radius: 60px;

    padding: 12px 18px;

    cursor: pointer;

    font-size: 1rem;
    font-weight: 600;

    backdrop-filter: blur(14px);

    box-shadow:
        0 10px 30px rgba(0, 0, 0, 0.12),
        0 4px 10px rgba(0, 0, 0, 0.08);

    transition:
        transform 0.25s ease,
        background 0.25s ease,
        box-shadow 0.25s ease;
}

.dark-mode .dark-mode-toggle {
    background: rgba(30, 30, 30, 0.9);
    color: white;
}

.dark-mode-toggle:hover {
    transform: translateY(-2px) scale(1.03);

    box-shadow:
        0 16px 40px rgba(0, 0, 0, 0.18),
        0 6px 18px rgba(0, 0, 0, 0.12);
}

/* ========== HERO ========== */
#hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    color: white;
}

.hero-background {
    position: absolute;
    inset: 0;
    background: linear-gradient(125deg, #001f1b 0%, #18325c 100%);
    z-index: -2;
    transition: background 0.3s;
}

.dark-mode .hero-background {
    background: linear-gradient(125deg, #0a2a25 0%, #18325c 100%);
}

.hero-overlay {
    width: 100%;
    background: rgba(0, 0, 0, 0.4);
    backdrop-filter: blur(4px);
    padding: 80px 20px;
}

.hero-content {
    max-width: 850px;
    margin: 0 auto;
    text-align: center;
}

.hero-content h1 {
    font-size: 4rem;
    font-weight: 800;
    letter-spacing: -0.02em;
    margin-bottom: 1rem;
}

.hero-accent {
    color: #ffb74d;
}

.tagline {
    font-size: 1.4rem;
    opacity: 0.92;
    margin-bottom: 2.5rem;
}

.welcome-text {
    background: rgba(255, 255, 255, 0.12);
    border-radius: 32px;
    padding: 2rem;
    backdrop-filter: blur(12px);
    margin-bottom: 2rem;
}

.welcome-text h2 {
    font-size: 1.8rem;
    margin-bottom: 1rem;
}

.welcome-text p {
    font-size: 1.05rem;
    line-height: 1.6;
}

.btn-details {
    display: inline-flex;
    align-items: center;
    gap: 12px;

    background: var(--accent-color);

    padding: 14px 36px;

    border-radius: 60px;

    font-weight: 600;
    font-size: 1.1rem;

    transition: all 0.25s;

    box-shadow: 0 8px 18px rgba(0, 0, 0, 0.2);

    text-decoration: none;
    color: white;
}

.btn-details:hover {
    background: #e65100;
    transform: translateY(-3px);
}

/* ========== DEMO SECTION ========== */
#demo {
    padding: 100px 0;
    background: var(--bg-light);
}

.section-title {
    font-size: 3rem;
    text-align: center;
    font-weight: 800;
    color: var(--primary-dark);
}

.section-intro {
    text-align: center;
    max-width: 700px;
    margin: 1rem auto 4rem;
    color: var(--text-light);
    font-size: 1.1rem;
}

/* ========== 70% WIDTH DEMO LAYOUT ========== */
.demo-vertical-list {
    width: 200%;        
    max-width: 1400px; 
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 48px;
}

.demo-item-vertical {
    display: flex;
    align-items: stretch;
    gap: 40px;

    background: var(--card-bg);

    border-radius: 32px;

    overflow: hidden;

    box-shadow: var(--shadow);

    transition:
        transform 0.35s ease,
        box-shadow 0.35s ease;

    border: 1px solid var(--border-light);

    padding: 32px;
}

.demo-item-vertical:hover {
    transform: translateY(-6px);

    box-shadow:
        0 18px 50px rgba(0, 0, 0, 0.14),
        0 8px 20px rgba(0, 0, 0, 0.08);
}

/* Alternate layout */
.demo-item-vertical:nth-child(even) {
    flex-direction: row-reverse;
}

/* ========== PREMIUM IMAGE CONTAINER ========== */
.demo-image {
    flex: 1.4;

    border-radius: 24px;

    overflow: hidden;

    background: var(--bg-light);

    position: relative;

    box-shadow:
        0 10px 25px rgba(0, 0, 0, 0.12),
        0 25px 50px rgba(0, 0, 0, 0.18);
}

.demo-image img {
    width: 100%;
    height: 100%;

    object-fit: cover;

    display: block;

    border-radius: 24px;

    transition:
        transform 0.45s ease,
        filter 0.35s ease;
}

.demo-item-vertical:hover .demo-image img {
    transform: scale(1.03);
    filter: brightness(1.03);
}

.demo-image::after {
    content: "";

    position: absolute;
    inset: 0;

    background:
        linear-gradient(
            to bottom,
            rgba(255,255,255,0.10),
            rgba(255,255,255,0.02) 35%,
            transparent 60%
        );

    pointer-events: none;

    border-radius: 24px;
}

/* ========== DEMO TEXT ========== */
.demo-caption {
    flex: 1;

    display: flex;
    flex-direction: column;
    justify-content: center;

    padding: 0 10px;
}

.demo-caption h3 {
    font-size: 2rem;
    font-weight: 800;

    color: var(--primary-dark);

    margin-bottom: 16px;
}

.demo-caption p {
    font-size: 1.08rem;
    line-height: 1.8;
    color: var(--text-light);
}

/* ========== VIDEO SECTION ========== */
.demo-video-vertical {
    flex-direction: column !important;
}

.demo-video-wrapper {
    width: 100%;

    overflow: hidden;

    border-radius: 24px;

    background: #000;

    box-shadow:
        0 10px 25px rgba(0, 0, 0, 0.12),
        0 25px 50px rgba(0, 0, 0, 0.18);
}

.demo-video-wrapper video {
    width: 100%;
    display: block;
    border-radius: 24px;
}

/* ========== FOOTER ========== */
#footer {
    background: var(--primary-dark);
    color: #e0f2f1;
    padding: 60px 0 30px;
}

.dark-mode #footer {
    background: #18325c;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));

    gap: 40px;

    margin-bottom: 40px;
}

.footer-section a {
    color: #b2dfdb;
    text-decoration: none;
}

.footer-bottom {
    text-align: center;

    border-top: 1px solid rgba(255, 255, 255, 0.15);

    padding-top: 30px;

    font-size: 0.9rem;
}

/* ========== RESPONSIVE ========== */
@media (max-width: 1200px) {
    .demo-vertical-list {
        width: 85%;
    }
}

@media (max-width: 900px) {

    .hero-content h1 {
        font-size: 2.8rem;
    }

    .section-title {
        font-size: 2.2rem;
    }

    .demo-vertical-list {
        width: 95%;
        gap: 32px;
    }

    .demo-item-vertical,
    .demo-item-vertical:nth-child(even) {
        flex-direction: column;
    }

    .demo-item-vertical {
        padding: 22px;
        gap: 24px;
    }

    .demo-caption {
        text-align: center;
        padding: 0;
    }

    .demo-caption h3 {
        font-size: 1.4rem;
    }

    .demo-caption p {
        font-size: 0.98rem;
    }

    .demo-image {
        width: 100%;
    }

    .dark-mode-toggle {
        top: 18px !important;
        right: 18px !important;
        padding: 10px 14px;
        font-size: 0.92rem;
    }
}

/* ========== AUTO HIDE BUTTONS ========== */
.hide-on-scroll {
    transform: translateY(-120px);
    opacity: 0;
    pointer-events: none;
}

/* ========== SMOOTH ANIMATION ========== */
.dark-mode-toggle,
.back-arrow-container {
    transition:
        transform 0.3s ease,
        opacity 0.3s ease;
}