/* ROOT VARIABLES & RESET */
:root {
    --bg-dark: #0f1115;
    --bg-card: #161b22;
    --bg-card-hover: #1c2128;
    --text-main: #e6edf3;
    --text-muted: #8b949e;

    /* Communication Module Accents (Purple/Violet/Indigo) */
    --accent-comm: #8b5cf6;
    --accent-call: #3b82f6;
    /* Blue */
    --accent-contact: #10b981;
    /* Green */
    --accent-sms: #f59e0b;
    /* Orange */
    --accent-glow: rgba(139, 92, 246, 0.15);

    --border-color: #30363d;
    --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
}

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

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

/* BACKGROUND */
.page-background {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    z-index: -1;
    background:
        radial-gradient(circle at 10% 50%, rgba(139, 92, 246, 0.08) 0%, transparent 40%),
        radial-gradient(circle at 90% 10%, rgba(59, 130, 246, 0.08) 0%, transparent 35%);
}

.docs-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
}

/* NAVIGATION HEADER */
.page-nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 4rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--border-color);
}

.back-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    background: none;
    border: none;
    color: var(--text-muted);
    font-family: var(--font-sans);
    font-weight: 500;
    cursor: pointer;
    transition: color 0.2s;
}

.back-btn:hover {
    color: var(--text-main);
}

.nav-breadcrumbs {
    font-size: 0.9rem;
    color: var(--text-muted);
}

.crumb-current {
    color: var(--accent-comm);
    font-weight: 600;
}

.crumb-sep {
    margin: 0 0.5rem;
    opacity: 0.5;
}

/* HERO SECTION */
.hero-section {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 4rem;
    margin-bottom: 5rem;
}

.hero-text h1 {
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 1.5rem;
    line-height: 1.1;
    background: linear-gradient(to right, #fff, #a78bfa);
    background-clip: text;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-desc {
    font-size: 1.2rem;
    color: var(--text-muted);
    max-width: 500px;
    margin-bottom: 2rem;
}

.tech-stack-pills {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
}

.pill {
    padding: 0.35rem 0.85rem;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--text-muted);
    background: rgba(255, 255, 255, 0.03);
}

/* NETWORK VISUAL */
.network-visual {
    width: 350px;
    height: 350px;
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
}

.center-node {
    width: 80px;
    height: 80px;
    background: var(--bg-card);
    border: 1px solid var(--accent-comm);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    z-index: 10;
    box-shadow: 0 0 30px rgba(139, 92, 246, 0.2);
}

.center-node .icon {
    font-size: 2rem;
}

.pulse-ring {
    position: absolute;
    width: 100%;
    height: 100%;
    border-radius: 50%;
    border: 2px solid var(--accent-comm);
    opacity: 0;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0% {
        transform: scale(1);
        opacity: 0.5;
    }

    100% {
        transform: scale(3);
        opacity: 0;
    }
}

.satellite-node {
    position: absolute;
    width: 50px;
    height: 50px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.3);
}

.satellite-node .icon {
    font-size: 1.2rem;
}

/* Positioning satellites */
.sat-1 {
    top: 40px;
    color: var(--accent-call);
}

.sat-2 {
    bottom: 60px;
    left: 20px;
    color: var(--accent-contact);
}

.sat-3 {
    bottom: 60px;
    right: 20px;
    color: var(--accent-sms);
}

.connection-line {
    position: absolute;
    width: 100px;
    height: 2px;
    background: linear-gradient(90deg, var(--border-color), transparent);
    z-index: -1;
}

/* CARDS CONTAINER */
.features-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2rem;
    margin-bottom: 5rem;
}

.feature-card {
    background: var(--bg-card);
    padding: 2rem;
    border-radius: 16px;
    border: 1px solid var(--border-color);
    transition: all 0.2s;
    position: relative;
    overflow: hidden;
}

.feature-card:hover {
    border-color: var(--border-color);
}

.call-card:hover {
    border-color: var(--accent-call);
}

.contact-card:hover {
    border-color: var(--accent-contact);
}

.sms-card:hover {
    border-color: var(--accent-sms);
}

.card-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.icon-box {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.call-icon {
    background: rgba(59, 130, 246, 0.1);
    color: var(--accent-call);
}

.contact-icon {
    background: rgba(16, 185, 129, 0.1);
    color: var(--accent-contact);
}

.sms-icon {
    background: rgba(245, 158, 11, 0.1);
    color: var(--accent-sms);
}

.card-header h3 {
    font-size: 1.25rem;
    font-weight: 700;
}

.desc {
    color: var(--text-muted);
    font-size: 0.95rem;
    margin-bottom: 1.5rem;
}

.feature-list {
    list-style: none;
    margin-bottom: 2rem;
}

.feature-list li {
    display: flex;
    gap: 0.5rem;
    color: var(--text-main);
    font-size: 0.9rem;
    margin-bottom: 0.5rem;
}

.feature-list span {
    color: var(--accent-comm);
    font-weight: bold;
}

.api-endpoint {
    background: rgba(0, 0, 0, 0.3);
    padding: 0.75rem;
    border-radius: 8px;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-family: var(--font-mono);
    font-size: 0.8rem;
    border: 1px solid var(--border-color);
}

.method {
    font-weight: 700;
    color: var(--accent-comm);
}

.url {
    color: var(--text-muted);
}

/* LOGIC SECTION */
.logic-section {
    background: rgba(255, 255, 255, 0.02);
    border-radius: 16px;
    border: 1px dashed var(--border-color);
    padding: 3rem;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.section-title {
    font-size: 1.75rem;
    font-weight: 800;
    margin-bottom: 3rem;
}

.flow-diagram {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    margin-bottom: 4rem;
    flex-wrap: wrap;
    justify-content: center;
}

.flow-step {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    padding: 1.5rem;
    border-radius: 12px;
    text-align: center;
    width: 180px;
}

.step-icon {
    font-size: 2rem;
    margin-bottom: 0.5rem;
}

.step-label {
    font-weight: 700;
    color: var(--text-main);
    margin-bottom: 0.25rem;
}

.step-sub {
    font-size: 0.75rem;
    color: var(--text-muted);
    font-family: var(--font-mono);
}

.flow-arrow {
    background: var(--accent-comm);
    color: #fff;
    padding: 0.25rem 0.75rem;
    border-radius: 100px;
    font-size: 0.75rem;
    font-weight: 600;
    position: relative;
    top: -10px;
}

/* CODE PREVIEW */
.code-preview-block {
    width: 100%;
    max-width: 800px;
    background: #0d1117;
    border: 1px solid var(--border-color);
    border-radius: 12px;
    overflow: hidden;
}

.code-header {
    background: rgba(255, 255, 255, 0.03);
    padding: 0.75rem 1rem;
    border-bottom: 1px solid var(--border-color);
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--text-muted);
}

.code-content {
    padding: 1.5rem;
    font-family: var(--font-mono);
    font-size: 0.9rem;
    color: #e6edf3;
    line-height: 1.5;
}

.kw {
    color: #ff7b72;
}

.str {
    color: #a5d6ff;
}

.comment {
    color: #8b949e;
    font-style: italic;
}

/* RESPONSIVE */
@media (max-width: 900px) {
    .hero-section {
        flex-direction: column;
        text-align: center;
    }

    .flow-diagram {
        flex-direction: column;
        gap: 2rem;
    }

    .flow-arrow {
        transform: rotate(90deg);
        top: 0;
    }
}

/* API REFERENCE SECTION */
.api-reference-section {
    display: flex;
    flex-direction: column;
    gap: 3rem;
}

.endpoint-group {
    margin-bottom: 2rem;
}

.group-title {
    font-size: 1.5rem;
    font-weight: 800;
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--border-color);
}

.group-call {
    color: var(--accent-call);
    border-color: rgba(59, 130, 246, 0.3);
}

.group-contact {
    color: var(--accent-contact);
    border-color: rgba(16, 185, 129, 0.3);
}

.group-sms {
    color: var(--accent-sms);
    border-color: rgba(245, 158, 11, 0.3);
}

.endpoint-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    overflow: hidden;
    margin-bottom: 1.5rem;
}

.endpoint-header {
    padding: 1rem 1.5rem;
    background: rgba(255, 255, 255, 0.02);
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    gap: 1rem;
}

.ep-method {
    font-family: var(--font-mono);
    font-weight: 700;
    font-size: 0.8rem;
    padding: 0.25rem 0.6rem;
    border-radius: 4px;
    background: rgba(139, 92, 246, 0.1);
    color: var(--accent-comm);
    border: 1px solid rgba(139, 92, 246, 0.2);
}

.ep-url {
    font-family: var(--font-mono);
    color: var(--text-main);
    font-size: 0.9rem;
    font-weight: 600;
}

.ep-desc {
    margin-left: auto;
    font-size: 0.85rem;
    color: var(--text-muted);
    font-style: italic;
}

.json-box {
    padding: 1.5rem;
    background: #0d1117;
    overflow-x: auto;
}

.json-pre {
    margin: 0;
    font-family: var(--font-mono);
    font-size: 0.85rem;
    line-height: 1.5;
    color: #e6edf3;
    white-space: pre;
}

/* JSON Syntax Highlight */
.j-key {
    color: #79c0ff;
}

.j-str {
    color: #a5d6ff;
}

.j-bool {
    color: #7ee787;
}

.j-num {
    color: #d2a8ff;
}

.j-cmt {
    color: #8b949e;
    font-style: italic;
}

.j-null {
    color: #ff7b72;
}