@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&family=Montserrat:wght@700;800&display=swap');

:root {
    --bg-dark: #0f172a;
    --bg-darker: #020617;
    --bg-card: #1e293b;
    --primary: #38bdf8;
    --secondary: #818cf8;
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --glass-border: rgba(255, 255, 255, 0.12);
    --accent-gradient: linear-gradient(135deg, var(--primary), var(--secondary));
    --intense-glow: 0 0 40px rgba(56, 189, 248, 0.35);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', sans-serif;
}

html {
    scroll-behavior: smooth;
}

body {
    background-color: var(--bg-dark);
    color: var(--text-main);
    line-height: 1.6;
    overflow-x: hidden;
}

h1, h2, h3 {
    font-family: 'Montserrat', sans-serif;
    font-weight: 800;
}

section {
    padding: 120px 0; /* Clear, airy feel */
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* Typography Scales */
.section-title {
    font-size: clamp(2rem, 5vw, 3rem);
    text-align: center;
    margin-bottom: 4rem;
    line-height: 1.2;
}

/* Glassmorphism V3 */
.glass {
    background: rgba(30, 41, 59, 0.5);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: 1.5rem;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

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

/* Navbar */
nav {
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    padding: 2rem 0;
    transition: all 0.4s ease;
}

nav.scrolled {
    background: rgba(15, 23, 42, 0.8);
    backdrop-filter: blur(15px);
    border-bottom: 1px solid var(--glass-border);
    padding: 1.2rem 0;
}

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

.logo {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--text-main);
    text-decoration: none;
    letter-spacing: -0.5px;
}

/* CTA Buttons */
@keyframes pulsateGlow {
    0% { transform: scale(1); box-shadow: 0 0 20px rgba(56, 189, 248, 0.4); }
    50% { transform: scale(1.05); box-shadow: 0 0 50px rgba(56, 189, 248, 0.7); }
    100% { transform: scale(1); box-shadow: 0 0 20px rgba(56, 189, 248, 0.4); }
}

.cta-btn {
    display: inline-block;
    padding: 1.4rem 3.5rem;
    background: var(--accent-gradient);
    color: white;
    font-weight: 800;
    text-decoration: none;
    border-radius: 1rem;
    font-size: 1.1rem;
    animation: pulsateGlow 2.5s infinite ease-in-out;
    border: none;
    cursor: pointer;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.cta-btn:hover {
    filter: brightness(1.1);
    transform: translateY(-3px);
}

/* Hero Section */
.hero {
    padding: 14rem 0 8rem;
    text-align: center;
    background: radial-gradient(circle at 50% 30%, rgba(56, 189, 248, 0.1), transparent 60%);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    width: 600px;
    height: 600px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(129, 140, 248, 0.08) 0%, transparent 70%);
    top: -100px;
    right: -150px;
    pointer-events: none;
}

.hero::after {
    content: '';
    position: absolute;
    width: 400px;
    height: 400px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(56, 189, 248, 0.07) 0%, transparent 70%);
    bottom: -50px;
    left: -100px;
    pointer-events: none;
}

.hero h1 {
    font-size: clamp(2rem, 6vw, 3.2rem);
    line-height: 1.15;
    margin-bottom: 2rem;
    letter-spacing: -1px;
}

.hero p {
    font-size: clamp(1rem, 2.5vw, 1.3rem);
    color: var(--text-muted);
    max-width: 750px;
    margin: 0 auto 4rem;
    font-weight: 400;
}

.hero-sub {
    display: inline-block;
    font-size: clamp(0.95rem, 2vw, 1.15rem);
    font-weight: 600;
    color: var(--text-muted);
    letter-spacing: 0.03em;
    margin-bottom: 1.2rem;
    padding: 0.4rem 1.2rem;
    border: 1px solid var(--glass-border);
    border-radius: 99px;
    background: rgba(255,255,255,0.04);
}

/* Problem Section */
.problems {
    background: var(--bg-darker);
}

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

@media (max-width: 900px) {
    .problem-grid {
        grid-template-columns: 1fr;
        max-width: 520px;
        margin: 0 auto;
    }
}

.problem-card {
    padding: 4rem 3rem;
    text-align: left;
}

.problem-card:hover {
    box-shadow: var(--intense-glow);
    border-color: rgba(56, 189, 248, 0.5);
    background: rgba(30, 41, 59, 0.7);
}

.problem-card h3 {
    margin: 2rem 0 1rem;
    color: var(--primary);
    font-size: 1.5rem;
}

.problem-card p {
    color: var(--text-muted);
}

/* Solution / Showcase Section */
.solution {
    padding: 10rem 0;
}

.mockup-container {
    max-width: 900px;
    margin: 0 auto 6rem;
    display: flex;
    justify-content: center;
}

.mockup-smartphone {
    width: 380px;
    border-radius: 4rem;
    overflow: hidden;
    box-shadow: 0 50px 100px -20px rgba(0,0,0,0.8);
    background: transparent;
}

.mockup-smartphone img {
    width: 100%;
    display: block;
}

/* Pricing Section */
.pricing-v3 {
    background: var(--bg-darker);
}

.price-box-v3 {
    max-width: 650px;
    margin: 0 auto;
    padding: 6rem 4rem;
    border: 2px solid rgba(56, 189, 248, 0.4);
    box-shadow: var(--intense-glow);
}

.price-number {
    font-size: clamp(4rem, 10vw, 6rem);
    font-weight: 900;
    line-height: 1;
    margin-bottom: 1rem;
}

/* Tally Form Section */
.form-section {
    background: radial-gradient(circle at center, rgba(56, 189, 248, 0.05), transparent 70%);
}

.form-container {
    max-width: 850px;
    margin: 0 auto;
    background: var(--bg-card);
    border-radius: 24px;
    padding: 40px;
    border: 1px solid var(--glass-border);
    box-shadow: 0 40px 100px rgba(0,0,0,0.5);
}

.form-container iframe {
    display: block;
    width: 100%;
}

/* Zalo Floating Button */
.zalo-float {
    position: fixed;
    bottom: 2.5rem;
    right: 2.5rem;
    background: #0068ff;
    color: white;
    padding: 1rem 1.8rem;
    border-radius: 4rem;
    display: flex;
    align-items: center;
    gap: 0.8rem;
    text-decoration: none;
    font-weight: 700;
    box-shadow: 0 15px 35px rgba(0, 104, 255, 0.4);
    z-index: 9999;
    transition: all 0.3s ease;
}

.zalo-float:hover {
    transform: translateY(-8px) scale(1.03);
    box-shadow: 0 20px 45px rgba(0, 104, 255, 0.6);
}

/* Animations */
[data-reveal] {
    opacity: 0;
    transition: all 1s cubic-bezier(0.2, 0.8, 0.2, 1);
}

.revealed {
    opacity: 1 !important;
    transform: translate(0, 0) scale(1) !important;
}

/* Media Queries */
@media (max-width: 768px) {
    section { padding: 80px 0; }
    .hero { padding: 8rem 0 5rem; }
    .hero h1 { font-size: clamp(1.7rem, 7vw, 2.5rem); letter-spacing: -0.5px; }
    .hero-sub { font-size: 0.88rem; }
    .mockup-smartphone { width: 100%; max-width: 320px; border-width: 8px; }
    .price-box-v3 { padding: 4rem 2rem; }
    .zalo-float span { display: none; }
    .zalo-float { padding: 1rem; right: 1.5rem; bottom: 1.5rem; }
    .form-container { padding: 20px; border-radius: 16px; }
}

/* ═══════════════════════════════════════
   DEMO LIBRARY — Clean List Design
   ═══════════════════════════════════════ */
.demo-library {
    background: var(--bg-darker);
    padding: 8rem 0;
}

.demo-library-sub {
    text-align: center;
    color: var(--text-muted);
    font-size: 1.05rem;
    margin-top: -2.5rem;
    margin-bottom: 4rem;
}

/* List container */
.demo-list {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

/* Each card */
.dl-card {
    display: grid;
    grid-template-columns: 8px 72px 1fr auto;
    align-items: center;
    gap: 2rem;
    background: rgba(15, 23, 42, 0.85);
    border: 1px solid rgba(255, 255, 255, 0.07);
    border-radius: 1.25rem;
    padding: 2.2rem 2.5rem;
    transition: transform 0.25s ease, border-color 0.25s ease, box-shadow 0.25s ease;
}

.dl-card:hover {
    transform: translateX(6px);
    border-color: rgba(56, 189, 248, 0.4);
    box-shadow: 0 8px 40px rgba(0,0,0,0.5), 0 0 20px rgba(56, 189, 248, 0.06);
}

/* Accent bar */
.dl-accent {
    width: 8px;
    height: 72px;
    border-radius: 99px;
    flex-shrink: 0;
    box-shadow: 0 0 18px rgba(56, 189, 248, 0.5);
}

/* Number */
.dl-num {
    font-size: 2.6rem;
    font-weight: 900;
    font-family: 'Montserrat', sans-serif;
    color: rgba(255,255,255,0.1);
    letter-spacing: -3px;
    line-height: 1;
    text-align: center;
    min-width: 54px;
}

/* Info block */
.dl-info {
    display: flex;
    flex-direction: column;
    gap: 0.35rem;
}

.dl-tag {
    font-size: 0.72rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: var(--primary);
    opacity: 0.9;
}

.dl-name {
    font-size: 1.35rem;
    font-weight: 800;
    color: var(--text-main);
    margin: 0;
    line-height: 1.2;
    letter-spacing: -0.3px;
}

.dl-desc {
    font-size: 0.87rem;
    color: var(--text-muted);
    line-height: 1.55;
    margin: 0;
    max-width: 520px;
}

/* CTA Button */
.dl-btn {
    display: inline-flex;
    align-items: center;
    white-space: nowrap;
    padding: 0.75rem 1.8rem;
    background: transparent;
    border: 1px solid rgba(56, 189, 248, 0.4);
    color: var(--primary);
    border-radius: 0.625rem;
    font-size: 0.88rem;
    font-weight: 700;
    text-decoration: none;
    transition: background 0.2s, color 0.2s, border-color 0.2s;
    flex-shrink: 0;
}

.dl-btn:hover {
    background: var(--primary);
    color: #0f172a;
    border-color: var(--primary);
    text-decoration: none;
}

/* Responsive */
@media (max-width: 768px) {
    .dl-card {
        grid-template-columns: 6px 1fr;
        grid-template-rows: auto auto;
        gap: 1rem 1.2rem;
        padding: 1.5rem;
    }
    .dl-accent {
        grid-row: 1 / 3;
        height: auto;
        align-self: stretch;
        width: 4px;
    }
    .dl-num { display: none; }
    .dl-info { grid-column: 2; }
    .dl-btn  { grid-column: 2; width: fit-content; margin-top: 0.25rem; }
}

/* Delivery Callout */
.delivery-callout {
    display: flex;
    align-items: center;
    gap: 1rem;
    background: rgba(56, 189, 248, 0.06);
    border: 1px solid rgba(56, 189, 248, 0.2);
    border-radius: 1rem;
    padding: 1rem 1.5rem;
    margin: 0 auto 2rem;
    max-width: 600px;
    text-align: left;
}

.delivery-callout .delivery-icon {
    font-size: 1.8rem;
    flex-shrink: 0;
}

.delivery-callout div {
    display: flex;
    flex-direction: column;
    gap: 0.2rem;
}

.delivery-callout strong {
    color: var(--text-main);
    font-size: 0.95rem;
}

.delivery-callout span {
    color: var(--text-muted);
    font-size: 0.82rem;
}



.demo-card {
    text-decoration: none !important;
    color: var(--text-main) !important;
    display: flex;
    flex-direction: column;
    background: rgba(30, 41, 59, 0.7);
    border: 1px solid var(--glass-border);
    border-radius: 1.25rem;
    overflow: hidden;
    transition: transform 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
}

.demo-card * {
    text-decoration: none;
}

.demo-card:hover {
    transform: translateY(-6px);
    border-color: rgba(56, 189, 248, 0.4);
    box-shadow: 0 20px 50px rgba(0,0,0,0.4), 0 0 30px rgba(56, 189, 248, 0.08);
}

/* Thumbnail area */
.demo-thumb {
    height: 180px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    position: relative;
    overflow: hidden;
}

.demo-thumb::before {
    content: '';
    position: absolute;
    inset: 0;
    opacity: 0.15;
    background-size: 40px 40px;
    background-image: 
        linear-gradient(rgba(255,255,255,0.05) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,0.05) 1px, transparent 1px);
}

.demo-thumb-dark {
    background: linear-gradient(135deg, #0f172a 0%, #1e293b 50%, #0f172a 100%);
}

.demo-thumb-platinum {
    background: linear-gradient(135deg, #0a0a0a 0%, #1a1a1a 50%, #0a0a0a 100%);
}

.demo-thumb-light {
    background: linear-gradient(135deg, #1e3a5f 0%, #1d4ed8 50%, #1e3a5f 100%);
}

.demo-thumb-icon {
    font-size: 3rem;
    position: relative;
    z-index: 1;
    filter: drop-shadow(0 4px 12px rgba(0,0,0,0.5));
}

.demo-style-tag {
    position: relative;
    z-index: 1;
    display: inline-block;
    padding: 0.25rem 0.8rem;
    background: rgba(56, 189, 248, 0.12);
    color: var(--primary);
    border: 1px solid rgba(56, 189, 248, 0.25);
    border-radius: 99px;
    font-size: 0.7rem;
    font-weight: 700;
    letter-spacing: 0.1em;
    text-transform: uppercase;
}

/* Card body */
.demo-body {
    padding: 1.5rem 1.6rem 1.8rem;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    flex: 1;
}

.demo-meta {
    font-size: 0.72rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--primary);
    opacity: 0.8;
}

.demo-body h3 {
    font-size: 1.15rem;
    font-weight: 800;
    color: var(--text-main);
    margin-top: 0.1rem;
}

.demo-body p {
    font-size: 0.84rem;
    color: var(--text-muted);
    line-height: 1.6;
    flex: 1;
}

.demo-cta {
    display: inline-block;
    margin-top: 0.8rem;
    font-size: 0.85rem;
    font-weight: 700;
    color: var(--primary);
    transition: gap 0.2s;
    letter-spacing: 0.02em;
}

.demo-card:hover .demo-cta {
    letter-spacing: 0.05em;
}

/* Responsive demo grid */
@media (max-width: 900px) {
    .demo-grid {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 600px) {
    .demo-grid {
        grid-template-columns: 1fr;
        max-width: 420px;
        margin: 0 auto;
    }
    .demo-library { padding: 5rem 0; }
    .demo-thumb { height: 140px; }
    .demo-thumb-icon { font-size: 2.2rem; }
}

/* ═══════════════════════════════════════
   CUSTOM GLASS FORM
   ═══════════════════════════════════════ */
.glass-form-container {
    padding: 3rem !important;
    max-width: 600px;
}

.glass-form {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    text-align: left;
}

.form-group label {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-main);
    letter-spacing: 0.02em;
}

.form-group label .required {
    color: #ef4444;
}

.glass-form input[type="text"],
.glass-form input[type="tel"] {
    width: 100%;
    padding: 1rem 1.2rem;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 0.8rem;
    color: var(--text-main);
    font-size: 1rem;
    font-family: 'Inter', sans-serif;
    transition: all 0.3s ease;
    backdrop-filter: blur(10px);
}

.glass-form input::placeholder {
    color: var(--text-muted);
    opacity: 0.6;
}

.glass-form input:focus {
    outline: none;
    border-color: var(--primary);
    background: rgba(255, 255, 255, 0.08);
    box-shadow: 0 0 15px rgba(56, 189, 248, 0.2);
}

.file-group {
    margin-top: 0.5rem;
}

.file-upload-wrapper {
    position: relative;
    width: 100%;
    height: 120px;
    border: 2px dashed rgba(255, 255, 255, 0.2);
    border-radius: 0.8rem;
    background: rgba(255, 255, 255, 0.02);
    transition: all 0.3s ease;
    cursor: pointer;
}

.file-upload-wrapper:hover {
    border-color: var(--primary);
    background: rgba(56, 189, 248, 0.05);
}

.file-upload-wrapper input[type="file"] {
    position: absolute;
    width: 100%;
    height: 100%;
    opacity: 0;
    cursor: pointer;
    z-index: 2;
}

.file-upload-ui {
    position: absolute;
    inset: 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 0.8rem;
    z-index: 1;
    pointer-events: none;
}

.file-upload-ui i {
    width: 32px;
    height: 32px;
    color: var(--primary);
}

.file-upload-ui span {
    color: var(--text-muted);
    font-size: 0.9rem;
    font-weight: 500;
}

.submit-btn {
    width: 100%;
    margin-top: 1.5rem;
    position: relative;
}

.btn-text {
    position: relative;
    z-index: 2;
}

.loader {
    width: 24px;
    height: 24px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 1s ease-in-out infinite;
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
    z-index: 2;
}

@keyframes spin {
    to { transform: translate(-50%, -50%) rotate(360deg); }
}

.error-msg {
    color: #ef4444;
    font-size: 0.85rem;
    margin-top: 0.5rem;
    font-weight: 500;
}

.status-msg {
    text-align: center;
    font-size: 0.95rem;
    font-weight: 600;
    padding: 1rem;
    border-radius: 0.5rem;
    margin-top: 1rem;
}

.status-msg.success {
    background: rgba(34, 197, 94, 0.1);
    color: #4ade80;
    border: 1px solid rgba(34, 197, 94, 0.2);
}

.status-msg.error {
    background: rgba(239, 68, 68, 0.1);
    color: #f87171;
    border: 1px solid rgba(239, 68, 68, 0.2);
}