:root {
    --bg-color: #F6F8FA;
    --text-color: #111827;
    --accent-color: #2563EB;
    --surface-color: rgba(255, 255, 255, 0.8);
    --border-color: rgba(17, 24, 39, 0.1);
    --shadow: 0 10px 30px rgba(0,0,0,0.05);
}

.dark-mode {
    --bg-color: #0F172A;
    --text-color: #E5E7EB;
    --accent-color: #2563EB;
    --surface-color: rgba(30, 41, 59, 0.8);
    --border-color: rgba(229, 231, 235, 0.1);
    --shadow: 0 10px 30px rgba(0,0,0,0.3);
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    overflow: hidden;
    transition: background-color 0.4s ease, color 0.4s ease;
}

/* Loader */
.loader {
    position: fixed;
    top: 0; left: 0; right: 0; bottom: 0;
    background-color: var(--bg-color);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
    transition: opacity 0.5s ease, visibility 0.5s ease;
}

.loader.hidden {
    opacity: 0;
    visibility: hidden;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid var(--border-color);
    border-top: 4px solid var(--accent-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* Top Bar */
.top-bar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    padding: 1.5rem 3rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    z-index: 100;
}

button {
    font-family: 'Inter', sans-serif;
    cursor: pointer;
    border: none;
    background: none;
}

#themeBtn {
    background-color: var(--surface-color);
    color: var(--text-color);
    border: 1px solid var(--border-color);
    padding: 0.6rem 1.2rem;
    border-radius: 20px;
    font-weight: 600;
    font-size: 0.9rem;
    backdrop-filter: blur(10px);
    transition: all 0.2s ease;
    box-shadow: var(--shadow);
}
#themeBtn:hover {
    transform: translateY(-2px);
    background-color: var(--accent-color);
    color: #fff;
}

.clock-container {
    font-variant-numeric: tabular-nums;
    font-weight: 600;
    font-size: 1.1rem;
    opacity: 0.8;
}

/* Slides Container */
.presentation {
    position: relative;
    width: 100vw;
    height: 100vh;
}

/* Slide Base */
.slide {
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 4rem;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.6s ease, transform 0.6s cubic-bezier(0.25, 1, 0.5, 1);
    transform: scale(0.95) translateY(20px);
    z-index: 1;
}

.slide.active {
    opacity: 1;
    pointer-events: auto;
    transform: scale(1) translateY(0);
    z-index: 10;
}

/* Content & Typography */
.content {
    max-width: 900px;
    text-align: center;
    width: 100%;
}

h1 {
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 1rem;
    line-height: 1.2;
    letter-spacing: -1px;
}

h2 {
    font-size: 2rem;
    font-weight: 400;
    margin-bottom: 2rem;
    color: var(--accent-color);
}

p {
    font-size: 1.3rem;
    line-height: 1.6;
    margin-bottom: 1rem;
    opacity: 0.9;
}

/* Animations Triggered by `.active` */
.animate-text {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.5s ease, transform 0.5s ease;
}

.slide.active .animate-text {
    opacity: 1;
    transform: translateY(0);
}

.slide.active h1.animate-text { transition-delay: 0.2s; }
.slide.active h2.animate-text { transition-delay: 0.4s; }
.slide.active p.animate-text { transition-delay: 0.6s; }
.slide.active .scale-in.animate-text { transition-delay: 0.4s; transform: scale(1); }

/* Lists & Staggered Animations */
.stagger-list {
    list-style: none;
    text-align: left;
    margin-top: 2rem;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
}

.stagger-list.center {
    align-items: center;
    text-align: center;
}

.stagger-list li {
    font-size: 1.3rem;
    line-height: 1.6;
    margin-bottom: 1.5rem;
    padding: 1.5rem 1.5rem 1.5rem 4rem;
    position: relative;
    opacity: 0;
    transform: translateX(-20px);
    transition: opacity 0.5s ease, transform 0.5s ease, box-shadow 0.3s ease, border-color 0.3s ease;
    text-align: left;
    background: var(--surface-color);
    border: 2px solid var(--border-color);
    border-radius: 12px;
}

.stagger-list li:hover {
    border-color: var(--accent-color);
    box-shadow: 0 10px 30px rgba(37, 99, 235, 0.2);
}

.stagger-list li::before {
    content: '→';
    color: var(--accent-color);
    position: absolute;
    left: 1.5rem;
    top: 1.5rem;
    font-weight: 800;
    font-size: 1.5rem;
}

.stagger-list .card, .stagger-list .box, .stagger-list .pill, .stagger-list .arrow {
    opacity: 0;
    transform: translateX(-20px);
    transition: opacity 0.5s ease, transform 0.5s ease;
}

.slide.active .stagger-list > *:nth-child(1) { transition-delay: 0.4s; opacity: 1; transform: translateX(0); }
.slide.active .stagger-list > *:nth-child(2) { transition-delay: 0.6s; opacity: 1; transform: translateX(0); }
.slide.active .stagger-list > *:nth-child(3) { transition-delay: 0.8s; opacity: 1; transform: translateX(0); }
.slide.active .stagger-list > *:nth-child(4) { transition-delay: 1.0s; opacity: 1; transform: translateX(0); }
.slide.active .stagger-list > *:nth-child(5) { transition-delay: 1.2s; opacity: 1; transform: translateX(0); }
.slide.active .stagger-list > *:nth-child(6) { transition-delay: 1.4s; opacity: 1; transform: translateX(0); }
.slide.active .stagger-list > *:nth-child(7) { transition-delay: 1.6s; opacity: 1; transform: translateX(0); }

/* Specialty Elements */
.hint {
    font-size: 1rem;
    opacity: 0.5 !important;
    margin-top: 3rem;
}
kbd {
    background-color: var(--surface-color);
    border: 1px solid var(--border-color);
    border-radius: 4px;
    padding: 0.2rem 0.5rem;
    font-family: inherit;
    font-size: 0.9rem;
    box-shadow: 0 2px 0 var(--border-color);
}

/* Cards & Pills */
.card {
    background: var(--surface-color);
    border: 2px solid var(--accent-color);
    padding: 2rem;
    border-radius: 12px;
    box-shadow: var(--shadow);
    backdrop-filter: blur(10px);
    font-size: 1.3rem;
    line-height: 1.6;
    transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
    position: relative;
    overflow: hidden;
}

.card:hover, .box:hover {
    transform: translateY(-8px) scale(1.02);
    box-shadow: 0 20px 40px rgba(37, 99, 235, 0.2);
    border-color: var(--accent-color);
}

.grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 2rem;
    width: 100%;
}

.grid .card {
    display: flex;
    justify-content: center;
    align-items: center;
    font-weight: 600;
}

.inline-list {
    flex-direction: row;
    justify-content: center;
    gap: 1.5rem;
    flex-wrap: wrap;
}
.inline-list li {
    margin: 0; 
    text-align: center;
}
.inline-list li::before { display: none; }

.stagger-list li.pill {
    background: var(--accent-color);
    color: white;
    padding: 1rem 2.5rem !important;
    border-radius: 50px;
    font-weight: 600;
    box-shadow: var(--shadow);
    transition: transform 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275), box-shadow 0.3s ease, background-color 0.3s ease !important;
    cursor: pointer;
    border: none;
}

.slide.active .stagger-list li.pill:hover {
    transform: translateY(-8px) scale(1.05) !important;
    box-shadow: 0 15px 30px rgba(37, 99, 235, 0.4);
    background-color: #1d4ed8;
}

.architecture {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    width: 100%;
}
.box {
    background: var(--surface-color);
    border: 2px solid var(--accent-color);
    padding: 1rem 2rem;
    border-radius: 8px;
    font-weight: 600;
    transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
    box-shadow: var(--shadow);
}
.arrow {
    font-size: 2rem !important;
    color: var(--accent-color) !important;
    padding: 0 !important;
}

/* Demo Button */
.demo-btn {
    display: inline-block;
    padding: 1rem 2.5rem;
    font-size: 1.2rem;
    font-weight: 600;
    color: #fff;
    background-color: var(--accent-color);
    border-radius: 8px;
    text-decoration: none;
    transition: background-color 0.2s ease, transform 0.2s ease;
    border: 1px solid transparent;
}

.demo-btn:hover {
    background-color: #1d4ed8;
    transform: translateY(-2px);
}

/* Console */
.console-text {
    font-family: monospace;
    text-align: left;
    background: #1e1e1e;
    color: #00ff00;
    padding: 1rem 2rem;
    border-radius: 8px;
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
    width: 100%;
    margin-left: auto;
    margin-right: auto;
    box-shadow: var(--shadow);
}
.console-text.prompt::after {
    content: '_';
    animation: blink 1s step-end infinite;
}
@keyframes blink { 50% { opacity: 0; } }

/* Bottom Controls */
.bottom-controls {
    position: fixed;
    bottom: 2rem;
    left: 0; right: 0;
    padding: 0 3rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    z-index: 100;
}

.counter {
    font-weight: 600;
    font-size: 1.1rem;
    opacity: 0.7;
    font-variant-numeric: tabular-nums;
}

.navigation {
    display: flex;
    gap: 1rem;
}

.nav-btn {
    background-color: var(--surface-color);
    color: var(--text-color);
    border: 1px solid var(--border-color);
    padding: 0.8rem 1.5rem;
    border-radius: 8px;
    font-weight: 600;
    font-size: 1rem;
    backdrop-filter: blur(10px);
    transition: all 0.2s ease;
    box-shadow: var(--shadow);
}
.nav-btn:hover:not(:disabled) {
    transform: translateY(-2px);
    background-color: var(--accent-color);
    color: #fff;
}
.nav-btn:disabled {
    opacity: 0.4;
    cursor: not-allowed;
    transform: none;
}

/* Progress Bar */
.progress-bar {
    position: fixed;
    bottom: 0; left: 0; right: 0;
    height: 6px;
    background-color: var(--border-color);
    z-index: 100;
}
.progress-fill {
    height: 100%;
    width: 0%;
    background-color: var(--accent-color);
    transition: width 0.4s cubic-bezier(0.25, 1, 0.5, 1);
}

/* Download Report Button Styles */
.download-btn {
    background-color: var(--accent-color);
    color: white;
    border: none;
    padding: 0.6rem 1.2rem;
    border-radius: 20px;
    font-weight: 600;
    font-size: 0.9rem;
    cursor: pointer;
    backdrop-filter: blur(10px);
    transition: all 0.2s ease;
    box-shadow: var(--shadow);
}

.download-btn:hover {
    transform: translateY(-2px);
    background-color: #1d4ed8;
    color: #fff;
}