:root {
    --navy: #071A2F;
    --deep-blue: #0B1F35;
    --blue: #2563EB;
    --cyan: #22D3EE;
    --white: #F8FAFC;
    --muted: #A8B4C7;
    --border: rgba(148, 163, 184, 0.22);
    --warning: #F59E0B;
    --card-bg: rgba(15, 40, 60, 0.82);
}

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

body, html {
    width: 100%;
    height: 100%;
    font-family: 'Inter', -apple-system, sans-serif;
    background-color: var(--navy);
    background:
        linear-gradient(rgba(7, 26, 47, 0.86), rgba(7, 26, 47, 0.92)),
        url("assets/serverless-background.jpg");
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    color: var(--white);
    overflow: hidden;
}

/* Subtle animated background glow */
.bg-animation {
    position: fixed;
    inset: 0;
    z-index: 0;
    pointer-events: none;
    opacity: 0.3;
    background-image:
        radial-gradient(circle at 15% 50%, rgba(37, 99, 235, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 85% 30%, rgba(34, 211, 238, 0.08) 0%, transparent 50%);
    animation: pulse 10s ease-in-out infinite alternate;
}

@keyframes pulse {
    0%   { opacity: 0.2; }
    100% { opacity: 0.45; }
}

/* ===================== Layout ===================== */
.presentation-container {
    position: relative;
    width: 100%;
    height: 100vh;
    display: flex;
    flex-direction: column;
    z-index: 1;
}

.progress-bar-container {
    position: absolute;
    top: 0; left: 0;
    width: 100%; height: 4px;
    background-color: var(--deep-blue);
    z-index: 10;
}

.progress-bar {
    height: 100%;
    width: 0%;
    background-color: var(--cyan);
    transition: width 0.4s ease;
    box-shadow: 0 0 10px var(--cyan);
}

/* ===================== Slides ===================== */
.slide {
    display: none;
    flex: 1;
    padding: 48px 80px 100px;
    overflow-y: auto;
    animation: fadeSlideUp 0.5s cubic-bezier(0.16, 1, 0.3, 1) forwards;
    background-color: rgba(7, 26, 47, 0.78);
}

#slide-1 {
    background-color: transparent;
}

#slide-2 {
    justify-content: center;
    text-align: center;
}
#slide-2 h2 {
    border-bottom: none;
    margin-bottom: 16px;
}

.slide.active {
    display: flex;
    flex-direction: column;
}

@keyframes fadeSlideUp {
    from { opacity: 0; transform: translateY(14px); }
    to   { opacity: 1; transform: translateY(0); }
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* ===================== Typography ===================== */
h1.main-title {
    font-size: 4.5rem;
    font-weight: 700;
    margin-bottom: 14px;
    text-transform: uppercase;
    letter-spacing: 2px;
    
    /* Text reflection gradient for SERVERLESS */
    background: linear-gradient(110deg, rgba(255, 255, 255, 0.7) 38%, #FFFFFF 48%, #FFFFFF 52%, rgba(255, 255, 255, 0.7) 62%);
    background-size: 200% auto;
    color: transparent;
    -webkit-background-clip: text;
    background-clip: text;
    filter: drop-shadow(0 0 15px rgba(34, 211, 238, 0.25));
    animation: textSweep 7s ease-in-out infinite;
}

h1.main-title .title-accent {
    /* Text reflection gradient for COMPUTING */
    background: linear-gradient(110deg, var(--cyan) 38%, #FFFFFF 48%, #FFFFFF 52%, var(--cyan) 62%);
    background-size: 200% auto;
    color: transparent;
    -webkit-background-clip: text;
    background-clip: text;
    animation: textSweep 7s ease-in-out infinite;
}

@keyframes textSweep {
    0%, 10% { background-position: -100% center; }
    90%, 100% { background-position: 200% center; }
}

h2 {
    font-size: 2.2rem;
    font-weight: 600;
    color: var(--cyan);
    margin-bottom: 28px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--border);
}

h3.subtitle {
    font-size: 1.7rem;
    color: var(--muted);
    margin-bottom: 34px;
    font-weight: 300;
}

h3 { font-size: 1.35rem; color: var(--cyan); margin-bottom: 12px; }
h4 { font-size: 1.1rem; color: var(--white); margin-bottom: 6px; }

p  { font-size: 1.15rem; line-height: 1.7; margin-bottom: 16px; color: var(--white); }
ul, ol { font-size: 1.1rem; line-height: 1.8; margin-bottom: 16px; padding-left: 26px; }
li { margin-bottom: 6px; }

.large-list li { font-size: 1.2rem; margin-bottom: 12px; }

.content-center {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    height: 100%;
}

.text-center { text-align: center; }

/* ===================== Presenter Info ===================== */
.presenter-info {
    background: var(--card-bg);
    border: 1px solid var(--border);
    padding: 24px 40px;
    border-radius: 12px;
    backdrop-filter: blur(10px);
    margin-top: 18px;
}
.presenter-info ul { list-style: none; padding: 0; }
.presenter-info p  { color: var(--muted); margin-bottom: 4px; font-size: 1rem; }
.presenter-info li { color: var(--white); font-weight: 600; margin-bottom: 3px; }
.presenter-list { display: flex; gap: 18px; justify-content: center; font-size: 1rem; margin-bottom: 0 !important; }

/* ===================== Grid Layouts ===================== */
.two-column {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 28px;
    align-items: stretch;
}

.grid-3   { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.grid-2x2 { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }

.card-row {
    display: flex;
    flex-wrap: wrap;
    gap: 14px;
}
.card-row > .card {
    flex: 1 1 160px;
    min-width: 140px;
}

.card-layout {
    max-width: 700px;
    margin: 0 auto;
    width: 100%;
}

/* ===================== Cards ===================== */
.card {
    background: var(--card-bg);
    border: 1px solid rgba(34, 211, 238, 0.12);
    backdrop-filter: blur(8px);
    padding: 24px;
    border-radius: 12px;
    height: 100%;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.16);
    transition: transform 0.3s;
}

.card:hover { transform: translateY(-3px); border-color: var(--blue); }
.card.primary   { border-top: 3px solid var(--blue); }
.card.secondary { border-top: 3px solid var(--cyan); }
.card.warning   { border-top: 3px solid var(--warning); }
.card.highlight { border-color: var(--cyan); }

/* ===================== Visuals ===================== */
#slide-1 .content-center {
    transform: translateY(-30px);
}

.hero-visual {
    margin-top: 0px;
    width: 100%;
    max-width: 480px;
    display: flex;
    justify-content: center;
}

/* Roadmap */
.roadmap {
    display: flex;
    justify-content: space-between;
    gap: 14px;
    margin-top: 34px;
    position: relative;
}

/* Connecting line */
.roadmap::before {
    content: '';
    position: absolute;
    top: 36px;
    left: 40px;
    width: calc(100% - 80px);
    height: 2px;
    background: var(--border);
    z-index: 0;
}

.roadmap-step {
    flex: 1;
    background: var(--card-bg);
    border: 1px solid rgba(34, 211, 238, 0.12);
    border-radius: 12px;
    padding: 20px 10px;
    text-align: center;
    backdrop-filter: blur(8px);
    transition: all 0.4s ease-out;
    position: relative;
    z-index: 1;
    opacity: 0;
    animation: fadeStepUp 0.8s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

.roadmap-step:hover {
    transform: translateY(-5px);
    border-color: var(--cyan);
    box-shadow: 0 6px 20px rgba(34, 211, 238, 0.15);
}

.roadmap-icon {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    background: var(--navy);
    border: 1px solid var(--cyan);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 12px;
    font-weight: 700;
    color: var(--cyan);
    font-size: 1.05rem;
    box-shadow: 0 0 10px rgba(34, 211, 238, 0.1);
    transition: all 0.4s ease;
}

.roadmap-step:hover .roadmap-icon {
    background: var(--cyan);
    color: var(--navy);
    box-shadow: 0 0 15px var(--cyan);
}

.roadmap-step h4 {
    color: var(--white);
    margin-bottom: 6px;
    font-size: 1.05rem;
}

.roadmap-desc {
    color: var(--muted);
    font-size: 0.9rem;
    margin: 0;
    line-height: 1.4;
}

@keyframes fadeStepUp {
    from { opacity: 0; transform: translateY(12px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Process Diagram */
.process-diagram { display: flex; justify-content: space-between; align-items: center; margin: 28px 0; gap: 8px; }
.process-node {
    flex: 1;
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 16px 8px;
    text-align: center;
    display: flex; flex-direction: column; align-items: center;
    font-size: 0.95rem;
}
.process-node svg { width: 32px; height: 32px; margin-bottom: 6px; fill: var(--cyan); }
.process-arrow { color: var(--blue); font-size: 1.6rem; flex-shrink: 0; animation: floatRight 2s infinite; }

@keyframes floatRight {
    0%   { transform: translateX(0); }
    50%  { transform: translateX(6px); }
    100% { transform: translateX(0); }
}

/* Vertical Process */
.vertical-process { display: flex; flex-direction: column; align-items: center; margin: 18px 0; }
.vertical-node {
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 12px 26px;
    text-align: center;
    width: 100%; max-width: 360px;
    font-weight: 600;
}
.vertical-node.highlight { border-color: var(--cyan); box-shadow: 0 0 10px rgba(34, 211, 238, 0.2); }
.vertical-arrow { color: var(--blue); font-size: 1.3rem; margin: 6px 0; }

/* Code Block */
.code-block {
    background: #0d1117; color: #c9d1d9;
    padding: 18px; border-radius: 8px;
    font-family: ui-monospace, SFMono-Regular, monospace;
    font-size: 1rem; border: 1px solid #30363d;
    overflow-x: auto; white-space: pre;
}
.code-keyword { color: #ff7b72; }
.code-func    { color: #d2a8ff; }
.code-string  { color: #a5d6ff; }
.code-comment { color: #8b949e; }

/* Comparison Table */
.comparison-table { margin: 8px 0 16px; }
.modern-table { width: 100%; border-collapse: collapse; }
.modern-table th,
.modern-table td { padding: 13px 18px; text-align: left; border-bottom: 1px solid var(--border); font-size: 1.05rem; }
.modern-table th { color: var(--white); font-weight: 600; background: var(--deep-blue); border-bottom: 2px solid var(--blue); }
.highlight-cell { color: var(--cyan); font-weight: 600; }

/* Cold Start Flow */
.cold-start-flow {
    display: flex;
    align-items: center;
    gap: 10px;
    font-family: monospace;
    font-size: 1rem;
    background: var(--navy);
    padding: 12px 16px;
    border-radius: 6px;
    margin-top: 10px;
    flex-wrap: wrap;
}
.cold-highlight {
    color: var(--warning);
    font-weight: bold;
    border: 1px dashed var(--warning);
    padding: 4px 10px;
    border-radius: 4px;
}

/* ===================== Quiz ===================== */
.mc-quiz { max-width: 100%; }
.mc-question {
    display: none;
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 24px;
}
.mc-question.active { display: block; animation: fadeSlideUp 0.4s; }
.mc-options { display: flex; flex-direction: column; gap: 8px; margin: 14px 0; }
.mc-option {
    background: var(--navy); border: 1px solid var(--border); color: var(--white);
    padding: 12px 16px; border-radius: 8px; cursor: pointer;
    font-size: 1rem; text-align: left; transition: all 0.2s;
}
.mc-option:hover   { background: rgba(37, 99, 235, 0.15); border-color: var(--blue); }
.mc-option.correct { background: rgba(34, 211, 238, 0.2); border-color: var(--cyan); color: var(--cyan); }
.mc-option.wrong   { background: rgba(245, 158, 11, 0.2); border-color: var(--warning); color: var(--warning); opacity: 0.7; }

.mc-feedback { margin-top: 14px; font-weight: 600; display: none; padding: 12px; border-radius: 8px; font-size: 0.95rem; }
.mc-feedback.visible { display: block; }
.mc-feedback.success { background: rgba(34, 211, 238, 0.1); color: var(--cyan); border-left: 4px solid var(--cyan); }

/* ===================== Buttons ===================== */
.btn {
    background: var(--blue); color: var(--white); border: none;
    padding: 10px 20px; border-radius: 6px; font-size: 1rem;
    font-weight: 600; cursor: pointer; transition: all 0.2s;
}
.btn:hover { background: #1d4ed8; transform: translateY(-2px); box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3); }

/* ===================== Navigation ===================== */
.controls {
    position: fixed; bottom: 0; left: 0; width: 100%;
    padding: 14px 36px;
    background: rgba(7, 26, 47, 0.92);
    backdrop-filter: blur(12px);
    border-top: 1px solid var(--border);
    display: flex; justify-content: space-between; align-items: center;
    z-index: 100;
}
.nav-group { display: flex; align-items: center; gap: 14px; }
.control-btn {
    background: transparent; color: var(--muted); border: none;
    font-size: 1rem; cursor: pointer; padding: 10px; border-radius: 6px;
    transition: all 0.2s;
    display: flex; align-items: center; gap: 8px;
}
.control-btn:hover { color: var(--white); background: var(--deep-blue); }
.nav-btn { color: var(--white); font-weight: 600; border: 1px solid var(--border); }
.nav-btn:hover { border-color: var(--blue); background: rgba(37, 99, 235, 0.1); }
.nav-btn:disabled { opacity: 0.3; cursor: not-allowed; border-color: var(--border); background: transparent; }
.slide-counter { color: var(--muted); font-variant-numeric: tabular-nums; letter-spacing: 1px; font-size: 0.9rem; }

/* ===================== Responsive ===================== */
@media (max-width: 1024px) {
    .slide { padding: 32px; padding-bottom: 100px; }
    h1.main-title { font-size: 3rem; }
    .two-column, .grid-3, .grid-2x2 { grid-template-columns: 1fr; gap: 16px; }
    .roadmap { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; margin-top: 20px; }
    .roadmap::before { display: none; }
    .process-diagram { flex-direction: column; }
    .process-arrow { transform: rotate(90deg); animation: floatDown 2s infinite; }
    @keyframes floatDown {
        0%   { transform: rotate(90deg) translateX(0); }
        50%  { transform: rotate(90deg) translateX(6px); }
        100% { transform: rotate(90deg) translateX(0); }
    }
}

@media (max-width: 768px) {
    .slide { padding: 16px; padding-bottom: 100px; }
    h1.main-title { font-size: 2rem; }
    h2 { font-size: 1.6rem; }
    .roadmap { grid-template-columns: 1fr; gap: 12px; }
    .controls { padding: 10px; flex-wrap: wrap; justify-content: center; gap: 8px; }
    .left-controls { display: none; }
    .presenter-list { flex-direction: column !important; gap: 2px !important; }
    .card-row > .card { min-width: 100%; }
}

@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}