:root {
    --primary-color: #0288D1;
    --primary-light: #E1F5FE;
    --accent-color: #4FC3F7;
    --bg-color: #ffffff;
    --section-bg: #f8fafc;
    --text-color: #334155;
    --text-muted: #64748b;
    --border-radius: 16px;
    --container-width: 900px;
    --shadow-soft: 0 10px 25px -5px rgba(0, 0, 0, 0.05), 0 8px 10px -6px rgba(0, 0, 0, 0.05);
    --shadow-strong: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1);
}

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

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

.rtl {
    direction: rtl;
    font-family: 'Inter', sans-serif;
}

.header-top {
    display: flex;
    justify-content: flex-end;
    padding: 20px;
    position: absolute;
    top: 0;
    right: 0;
    width: 100%;
    z-index: 100;
}

#lang-select {
    padding: 8px 12px;
    border-radius: 20px;
    border: 1px solid #e2e8f0;
    background: white;
    font-family: inherit;
    font-size: 0.9rem;
    color: var(--text-color);
    cursor: pointer;
    outline: none;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
    transition: border-color 0.3s;
}

#lang-select:hover {
    border-color: var(--primary-color);
}

.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 24px;
}

/* Header */
header {
    background: linear-gradient(180deg, #f0f9ff 0%, #ffffff 100%);
    padding: 100px 0 80px;
    text-align: center;
}

.logo-area {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px;
    margin-bottom: 24px;
}

.header-icons {
    display: flex;
    gap: 30px;
    align-items: center;
}

.logo {
    width: 90px;
    height: auto;
    filter: drop-shadow(0 10px 15px rgba(2, 136, 209, 0.2));
    transition: transform 0.3s ease;
}

.logo:hover {
    transform: scale(1.1);
}

.logo.pro {
    filter: drop-shadow(0 10px 20px rgba(0, 188, 212, 0.4));
}

h1 {
    font-size: 2.8rem;
    font-weight: 700;
    color: #0f172a;
    letter-spacing: -0.025em;
}

.tagline {
    font-size: 1.25rem;
    color: var(--primary-color);
    font-weight: 500;
}

/* Sections */
.section {
    padding: 100px 0;
}

h2 {
    font-size: 2.2rem;
    margin-bottom: 60px;
    text-align: center;
    color: #1e293b;
    position: relative;
}

h2::after {
    content: '';
    position: absolute;
    bottom: -12px;
    left: 50%;
    transform: translateX(-50%);
    width: 48px;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
    border-radius: 2px;
}

.abstract-content {
    text-align: center;
    max-width: 720px;
    margin: 0 auto;
    font-size: 1.1rem;
}

.highlight-text {
    margin-top: 32px;
    font-size: 1.4rem;
    font-weight: 700;
    background: linear-gradient(90deg, #0288D1, #00BCD4);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

/* Feature Cards */
.feature-card {
    display: flex;
    align-items: center;
    gap: 40px;
    margin-bottom: 60px;
    background-color: var(--section-bg);
    padding: 60px;
    border-radius: 24px;
    transition: transform 0.3s ease, box-shadow 0.3s ease, flex-direction 0.5s ease, padding 0.5s ease;
}

.feature-card.reverse {
    flex-direction: row-reverse;
}

.feature-card.vertical {
    flex-direction: column;
    text-align: center;
    gap: 30px;
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-soft);
}

.feature-text {
    flex: 1.2;
    transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.feature-card.vertical .feature-text {
    width: 100%;
    max-width: 600px;
}

.feature-text h3 {
    font-size: 1.8rem;
    margin-bottom: 24px;
    color: #0f172a;
    display: flex;
    align-items: center;
    gap: 12px;
}

.feature-visual {
    flex: 1;
    display: flex;
    justify-content: center;
    transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.feature-card.vertical .feature-visual {
    width: 100%;
}

/* Responsive */
@media (max-width: 768px) {

    .feature-card,
    .feature-card.reverse {
        flex-direction: column;
        text-align: center;
        padding: 30px;
        gap: 20px;
    }

    .feature-text,
    .feature-visual {
        width: 100%;
    }
}

/* Mobile Frame */
.mobile-frame {
    width: 100%;
    max-width: 280px;
    aspect-ratio: 9 / 19;
    background: #1e293b;
    border: 12px solid #0f172a;
    border-radius: 36px;
    overflow: hidden;
    position: relative;
    box-shadow: var(--shadow-strong);
    transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.mobile-frame.landscape {
    max-width: 640px;
    aspect-ratio: 19 / 9;
    border-width: 8px;
    border-radius: 20px;
}

.video-preview.landscape {
    margin-top: 10px;
    width: 100%;
}

.card-video {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.action-list {
    margin-top: 24px;
    list-style: none;
    display: grid;
    grid-template-columns: 1fr;
    gap: 12px;
}

.action-list li {
    padding: 12px 16px;
    background: white;
    border-radius: 12px;
    font-size: 0.95rem;
    font-weight: 500;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
    display: flex;
    align-items: center;
    gap: 10px;
}

.action-list li::before {
    content: '✓';
    color: var(--primary-color);
    font-weight: bold;
}

/* Feature Grid Cleaned up - Using Feature Cards instead */
.backup-visual {
    width: 200px;
    height: 200px;
    background: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-subtle);
}

.grid-icon.large {
    font-size: 80px;
}

.grid-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-strong);
    border-color: var(--accent-color);
}

.grid-icon {
    font-size: 2.5rem;
}

.grid-card h3 {
    font-size: 1.25rem;
    color: #0f172a;
}

.thumbnail-group {
    display: flex;
    gap: 10px;
    margin-top: 10px;
}

.thumbnail-group img {
    width: calc(50% - 5px);
    border-radius: 8px;
    border: 1px solid #eee;
}

/* Steps */
.step-container {
    display: flex;
    flex-direction: column;
    gap: 40px;
}

.step {
    display: flex;
    gap: 40px;
    background-color: var(--section-bg);
    padding: 40px;
    border-radius: 24px;
    align-items: center;
}

.step-number {
    font-size: 3rem;
    font-weight: 800;
    color: var(--primary-color);
    opacity: 0.25;
    min-width: 60px;
}

.step-content {
    flex: 2;
}

.step-content h4 {
    font-size: 1.4rem;
    margin-bottom: 12px;
    color: #0f172a;
}

.step-visual {
    flex: 1;
    max-width: 200px;
}

.step-video {
    width: 100%;
    border-radius: 16px;
    box-shadow: var(--shadow-soft);
}

/* Table */
.table-wrapper {
    background: white;
    border-radius: 24px;
    padding: 32px;
    box-shadow: var(--shadow-soft);
    border: 1px solid #e2e8f0;
    margin-top: 40px;
}

table {
    width: 100%;
    border-collapse: collapse;
}

th,
td {
    padding: 20px;
    text-align: center;
    border-bottom: 1px solid #f1f5f9;
}

th {
    font-weight: 600;
    color: var(--text-muted);
    font-size: 0.9rem;
    text-transform: uppercase;
}

.plan-icon {
    width: 72px;
    height: 72px;
    display: block;
    margin: 0 auto 12px;
    border-radius: 12px;
}

th {
    vertical-align: bottom;
    padding-bottom: 20px;
}

td strong {
    color: var(--primary-color);
}

/* Pro Link Section */
.pro-link-container {
    margin-top: 40px;
    text-align: center;
    padding-bottom: 20px;
}

.pro-link-button {
    display: inline-flex;
    align-items: center;
    background: linear-gradient(135deg, #2c3e50, #000000);
    color: white;
    text-decoration: none;
    padding: 16px 32px;
    border-radius: 50px;
    font-size: 1.1rem;
    font-weight: 600;
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
    transition: all 0.3s ease;
}

.pro-link-button:hover {
    transform: translateY(-3px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.3);
    background: linear-gradient(135deg, #34495e, #1a1a1a);
}

.btn-icon {
    width: 32px;
    height: 32px;
    margin-right: 12px;
    border-radius: 6px;
}

.pro-link-note {
    margin-top: 12px;
    font-size: 0.9rem;
    color: var(--text-muted);
}

/* Footer & Contact */
.contact-card {
    text-align: center;
    background: linear-gradient(135deg, #0288D1 0%, #00BCD4 100%);
    color: white;
    padding: 60px;
    border-radius: 24px;
    margin-top: 40px;
}

.contact-card .email a {
    color: white;
    font-size: 1.8rem;
    font-weight: 700;
    text-decoration: none;
    border-bottom: 2px solid rgba(255, 255, 255, 0.3);
    transition: border-color 0.3s ease;
}

.contact-card .email a:hover {
    border-bottom-color: white;
}

/* Animation */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 1s cubic-bezier(0.4, 0, 0.2, 1), transform 1s cubic-bezier(0.4, 0, 0.2, 1);
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Note Box */
.note-box {
    margin-top: 40px;
    padding: 24px;
    background-color: var(--primary-light);
    border-left: 4px solid var(--primary-color);
    border-radius: 12px;
    color: #0369a1;
}

/* Footer */
footer {
    padding: 60px 0;
    text-align: center;
    color: var(--text-muted);
}

/* Responsive */
@media (max-width: 850px) {

    .feature-card,
    .feature-card.reverse,
    .step {
        flex-direction: column;
        text-align: center;
        padding: 40px;
    }

    .feature-text h3 {
        justify-content: center;
    }

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

    .action-list {
        text-align: left;
    }

    .step-visual {
        max-width: 100%;
    }
}