/* ==========================================================================
   20241204.com - A Scholar's Chronicle
   Dark academia + forest green immersive scroll experience
   ========================================================================== */

/* CSS Custom Properties */
:root {
    --deep-bg: #0d1a0f;
    --mid-bg: #1a2e1c;
    --evergreen: #2d5a3d;
    --fern-dark: #3a7a4f;
    --aged-gold: #c9a84c;
    --candlelight: #d4a843;
    --parchment: #e8dcc8;
    --forest-fog: #9ba89e;
    --ink-stain: #6b2d3e;

    --font-display: 'Playfair Display', Georgia, serif;
    --font-body: 'Fira Sans', 'Helvetica Neue', sans-serif;
    --font-mono: 'JetBrains Mono', 'Courier New', monospace;

    --text-column-width: 38em;
    --scroll-progress: 0;
}

/* Reset */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-snap-type: y proximity;
    scroll-behavior: smooth;
    background-color: var(--deep-bg);
}

body {
    font-family: var(--font-body);
    font-weight: 300;
    font-size: 18px;
    line-height: 1.72;
    color: var(--parchment);
    letter-spacing: 0.02em;
    background: var(--deep-bg);
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ==========================================================================
   SVG Filters & Grain Overlay
   ========================================================================== */

.svg-filters {
    position: absolute;
    width: 0;
    height: 0;
    overflow: hidden;
}

.grain-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 1000;
    pointer-events: none;
    filter: url(#grain-filter);
    opacity: 0.04;
    mix-blend-mode: soft-light;
}

/* ==========================================================================
   Mid-ground Botanical Layer
   ========================================================================== */

.midground-layer {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 1;
    pointer-events: none;
    opacity: 0.08;
}

.bg-leaf {
    position: absolute;
    opacity: 0.15;
}

.bg-leaf-1 {
    width: 200px;
    top: 10%;
    right: 5%;
    transform: rotate(15deg);
}

.bg-leaf-2 {
    width: 160px;
    top: 40%;
    left: 3%;
    transform: rotate(-20deg);
}

.bg-leaf-3 {
    width: 120px;
    top: 70%;
    right: 15%;
    transform: rotate(35deg);
}

/* ==========================================================================
   Living Bookmark (Vertical Margin Rule)
   ========================================================================== */

.margin-rule {
    position: fixed;
    left: 32px;
    top: 0;
    width: 2px;
    height: 100vh;
    z-index: 100;
    pointer-events: none;
    background: linear-gradient(
        to bottom,
        transparent 0%,
        var(--evergreen) calc(var(--scroll-progress) * 100% - 5%),
        var(--fern-dark) calc(var(--scroll-progress) * 100%),
        transparent calc(var(--scroll-progress) * 100% + 5%)
    );
    opacity: 0.7;
    transition: opacity 0.3s ease;
}

.margin-rule::before {
    content: '';
    position: absolute;
    left: -4px;
    top: calc(var(--scroll-progress) * 100%);
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--fern-dark);
    box-shadow: 0 0 8px var(--evergreen), 0 0 16px rgba(45, 90, 61, 0.4);
    animation: pulse-bookmark 2.4s ease-in-out infinite;
    transform: translateY(-50%);
}

@keyframes pulse-bookmark {
    0%, 100% {
        box-shadow: 0 0 4px var(--evergreen), 0 0 8px rgba(45, 90, 61, 0.3);
    }
    50% {
        box-shadow: 0 0 12px var(--fern-dark), 0 0 24px rgba(58, 122, 79, 0.5);
    }
}

/* ==========================================================================
   Leaf-fall Particles
   ========================================================================== */

.leaf-fall-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 50;
    pointer-events: none;
    overflow: hidden;
}

.falling-leaf {
    position: absolute;
    top: -40px;
    width: 20px;
    height: 28px;
    opacity: 0;
    will-change: transform, opacity;
}

.falling-leaf svg {
    width: 100%;
    height: 100%;
}

.falling-leaf.active {
    opacity: 0.6;
    animation: leaf-drift linear forwards;
}

@keyframes leaf-drift {
    0% {
        opacity: 0;
        transform: translateY(0) rotate(0deg);
    }
    10% {
        opacity: 0.6;
    }
    90% {
        opacity: 0.4;
    }
    100% {
        opacity: 0;
        transform: translateY(100vh) rotate(360deg);
    }
}

/* ==========================================================================
   Hero / Opening Scene
   ========================================================================== */

.hero-scene {
    position: relative;
    width: 100%;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    background: linear-gradient(180deg, var(--deep-bg) 0%, var(--mid-bg) 50%, var(--deep-bg) 100%);
    scroll-snap-align: start;
    z-index: 10;
}

.canopy-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 1;
}

.canopy-svg {
    width: 100%;
    height: 100%;
}

/* Drifting leaves in canopy */
.drifting-leaf {
    will-change: transform;
}

.drift-1 { animation: drift-slow 8s ease-in-out infinite; }
.drift-2 { animation: drift-slow 10s ease-in-out infinite 1s; }
.drift-3 { animation: drift-slow 9s ease-in-out infinite 2s; }
.drift-4 { animation: drift-slow 11s ease-in-out infinite 0.5s; }
.drift-5 { animation: drift-slow 7s ease-in-out infinite 3s; }

@keyframes drift-slow {
    0%, 100% {
        transform: translateY(0) rotate(0deg);
    }
    25% {
        transform: translateY(15px) rotate(3deg);
    }
    50% {
        transform: translateY(30px) rotate(-2deg);
    }
    75% {
        transform: translateY(20px) rotate(4deg);
    }
}

/* Tree rings animation */
.tree-rings .ring {
    opacity: 0;
    transform-origin: center;
    animation: ring-appear 0.8s ease-out forwards;
}

.ring-1 { animation-delay: 0.2s; }
.ring-2 { animation-delay: 0.5s; }
.ring-3 { animation-delay: 0.8s; }
.ring-4 { animation-delay: 1.1s; }
.ring-5 { animation-delay: 1.4s; }
.ring-6 { animation-delay: 1.7s; }
.ring-7 { animation-delay: 2.0s; }

@keyframes ring-appear {
    0% {
        opacity: 0;
        transform: scale(0.5);
    }
    100% {
        opacity: 0.6;
        transform: scale(1);
    }
}

/* Hero Title */
.hero-title {
    position: relative;
    z-index: 10;
    text-align: center;
}

.site-title {
    font-family: var(--font-display);
    font-weight: 700;
    font-size: clamp(3rem, 8vw, 7rem);
    color: var(--aged-gold);
    letter-spacing: 0.06em;
    margin-bottom: 0.3em;
    text-shadow: 0 0 40px rgba(201, 168, 76, 0.3);
    opacity: 0;
    transform: translateY(20px);
    animation: title-reveal 1.5s ease-out 0.5s forwards;
}

.site-subtitle {
    font-family: var(--font-display);
    font-weight: 400;
    font-style: italic;
    font-size: clamp(1rem, 2.5vw, 1.5rem);
    color: var(--forest-fog);
    letter-spacing: 0.12em;
    text-transform: lowercase;
    opacity: 0;
    transform: translateY(12px);
    animation: title-reveal 1.2s ease-out 1.2s forwards;
}

@keyframes title-reveal {
    0% {
        opacity: 0;
        transform: translateY(20px);
        filter: blur(4px);
    }
    100% {
        opacity: 1;
        transform: translateY(0);
        filter: blur(0);
    }
}

/* ==========================================================================
   Fog Transitions
   ========================================================================== */

.fog-transition {
    position: relative;
    width: 100%;
    height: 30vh;
    z-index: 15;
    background: linear-gradient(
        180deg,
        transparent 0%,
        var(--deep-bg) 40%,
        var(--deep-bg) 60%,
        transparent 100%
    );
    pointer-events: none;
}

/* ==========================================================================
   Chapters
   ========================================================================== */

.chapter {
    position: relative;
    min-height: 100vh;
    padding: 8vh 2rem 12vh;
    scroll-snap-align: start;
    z-index: 10;
    contain: layout style;
}

.chapter-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    background: linear-gradient(180deg, var(--deep-bg) 0%, var(--mid-bg) 15%, var(--mid-bg) 85%, var(--deep-bg) 100%);
}

.clearing-bg {
    background: linear-gradient(180deg, var(--deep-bg) 0%, var(--mid-bg) 10%, #1e3520 50%, var(--mid-bg) 90%, var(--deep-bg) 100%);
}

/* ==========================================================================
   Botanical Dividers
   ========================================================================== */

.botanical-divider {
    display: flex;
    justify-content: center;
    margin-bottom: 4vh;
    opacity: 0.8;
}

.divider-svg {
    width: 300px;
    height: auto;
}

.divider-wide {
    width: 600px;
}

.draw-path {
    stroke-dasharray: 1000;
    stroke-dashoffset: 1000;
    transition: stroke-dashoffset 0.05s linear;
}

.draw-path.drawn {
    stroke-dashoffset: 0;
}

/* ==========================================================================
   Chapter Numerals
   ========================================================================== */

.chapter-numeral {
    text-align: center;
    margin-bottom: 3vh;
}

.chapter-left .chapter-numeral {
    text-align: left;
    padding-left: calc(50% - var(--text-column-width) / 2);
}

.chapter-right .chapter-numeral {
    text-align: right;
    padding-right: calc(50% - var(--text-column-width) / 2);
}

.numeral {
    font-family: var(--font-display);
    font-weight: 700;
    font-size: clamp(3rem, 6vw, 5rem);
    color: var(--aged-gold);
    letter-spacing: 0.08em;
    opacity: 0.7;
    display: inline-block;
}

/* ==========================================================================
   Text Column & Content
   ========================================================================== */

.text-column {
    max-width: var(--text-column-width);
    margin: 0 auto;
    padding: 0 2rem;
}

.chapter-left .text-column {
    margin-left: calc(50% - var(--text-column-width) / 2);
    margin-right: auto;
}

.chapter-right .text-column {
    margin-left: auto;
    margin-right: calc(50% - var(--text-column-width) / 2);
}

.chapter-heading {
    font-family: var(--font-display);
    font-weight: 700;
    font-size: clamp(1.8rem, 3vw, 2.4rem);
    color: var(--parchment);
    margin-bottom: 1.5em;
    letter-spacing: 0.02em;
}

/* Drop Caps */
.drop-cap {
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 4.5em;
    float: left;
    line-height: 0.7;
    color: var(--aged-gold);
    margin-right: 0.08em;
    margin-top: 0.08em;
    opacity: 0;
    transform: translateY(8px);
    filter: blur(2px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out, filter 0.6s ease-out;
}

.drop-cap.visible {
    opacity: 1;
    transform: translateY(0);
    filter: blur(0);
}

.body-text {
    font-family: var(--font-body);
    font-weight: 300;
    font-size: 1rem;
    line-height: 1.72;
    color: var(--parchment);
    margin-bottom: 1.5em;
    hyphens: auto;
    -webkit-hyphens: auto;
    letter-spacing: 0.02em;
}

/* Marginalia */
.marginalia {
    margin: 2em 0;
    padding-left: 1.5em;
    border-left: 1px solid var(--forest-fog);
    position: relative;
}

.annotation {
    font-family: var(--font-mono);
    font-size: 0.8em;
    color: var(--aged-gold);
    line-height: 1.6;
    opacity: 0.8;
    display: block;
}

.annotation em {
    font-style: italic;
}

/* Pull Quote */
.pull-quote {
    margin: 3em 0;
    padding: 1.5em 2em;
    position: relative;
}

.pull-quote::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    width: 3px;
    height: 100%;
    background: linear-gradient(to bottom, var(--aged-gold), transparent);
    border-radius: 1px;
}

.pull-quote p {
    font-family: var(--font-display);
    font-weight: 400;
    font-style: italic;
    font-size: clamp(1.1rem, 2vw, 1.4rem);
    color: var(--aged-gold);
    line-height: 1.6;
    letter-spacing: 0.01em;
}

/* ==========================================================================
   Chapter V - The Clearing (Full-Width Finale)
   ========================================================================== */

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

.chapter-clearing .chapter-numeral {
    text-align: center;
    padding-left: 0;
    padding-right: 0;
}

.clearing-content {
    max-width: 56em;
    margin: 0 auto;
    padding: 0 2rem;
}

.clearing-heading {
    font-size: clamp(2rem, 4vw, 3rem);
    margin-bottom: 1em;
}

.clearing-text {
    font-size: 1.05rem;
    text-align: left;
    max-width: 42em;
    margin-left: auto;
    margin-right: auto;
    margin-bottom: 1.8em;
}

.closing-sigil {
    margin: 6vh auto 0;
    width: 80px;
    height: 80px;
    opacity: 0.6;
    animation: sigil-pulse 3s ease-in-out infinite;
}

.closing-sigil svg {
    width: 100%;
    height: 100%;
}

@keyframes sigil-pulse {
    0%, 100% {
        opacity: 0.4;
        transform: scale(1);
    }
    50% {
        opacity: 0.7;
        transform: scale(1.05);
    }
}

/* ==========================================================================
   Leaf Pile (Bottom Accumulation)
   ========================================================================== */

.leaf-pile {
    position: relative;
    width: 100%;
    height: 80px;
    z-index: 10;
    overflow: hidden;
    pointer-events: none;
}

.pile-leaf {
    position: absolute;
    bottom: 0;
    width: 18px;
    height: 24px;
    opacity: 0;
    transition: opacity 0.5s ease;
}

.pile-leaf.visible {
    opacity: 0.5;
}

.pile-leaf svg {
    width: 100%;
    height: 100%;
}

/* ==========================================================================
   Chapter Navigation (Leaf Markers)
   ========================================================================== */

.chapter-nav {
    position: fixed;
    bottom: 30px;
    right: 30px;
    z-index: 200;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.leaf-marker {
    width: 28px;
    height: 36px;
    background: none;
    border: none;
    cursor: pointer;
    color: var(--forest-fog);
    opacity: 0.5;
    transition: opacity 0.3s ease, color 0.3s ease, transform 0.3s ease;
    padding: 0;
}

.leaf-marker:hover {
    opacity: 0.8;
    color: var(--fern-dark);
    transform: scale(1.15);
}

.leaf-marker.active {
    opacity: 1;
    color: var(--fern-dark);
}

.leaf-marker.active .leaf-fill {
    fill: var(--fern-dark);
    fill-opacity: 0.4;
}

.leaf-marker.active {
    animation: pulse-leaf 2.4s ease-in-out infinite;
}

@keyframes pulse-leaf {
    0%, 100% {
        filter: drop-shadow(0 0 0px var(--evergreen));
    }
    50% {
        filter: drop-shadow(0 0 12px var(--fern-dark));
    }
}

.leaf-marker.completed {
    opacity: 0.9;
    color: var(--evergreen);
}

.leaf-marker.completed .leaf-fill {
    fill: var(--evergreen);
    fill-opacity: 0.6;
}

/* ==========================================================================
   Responsive
   ========================================================================== */

@media (max-width: 900px) {
    .chapter-left .text-column,
    .chapter-right .text-column {
        margin-left: auto;
        margin-right: auto;
    }

    .chapter-left .chapter-numeral,
    .chapter-right .chapter-numeral {
        text-align: center;
        padding-left: 0;
        padding-right: 0;
    }

    .margin-rule {
        left: 12px;
    }

    .chapter-nav {
        bottom: 16px;
        right: 16px;
    }

    .leaf-marker {
        width: 22px;
        height: 28px;
    }

    .divider-svg {
        width: 240px;
    }

    .divider-wide {
        width: 400px;
    }
}

@media (max-width: 600px) {
    body {
        font-size: 16px;
    }

    .text-column {
        padding: 0 1rem;
    }

    .clearing-content {
        padding: 0 1rem;
    }

    .margin-rule {
        display: none;
    }

    .chapter {
        padding: 6vh 1rem 8vh;
    }

    .hero-scene {
        height: 100svh;
    }

    .drop-cap {
        font-size: 3.5em;
    }

    .divider-svg {
        width: 200px;
    }

    .divider-wide {
        width: 300px;
    }
}

/* ==========================================================================
   Selection & Utility
   ========================================================================== */

::selection {
    background: var(--evergreen);
    color: var(--parchment);
}

::-moz-selection {
    background: var(--evergreen);
    color: var(--parchment);
}

/* Smooth scrollbar styling for webkit browsers */
::-webkit-scrollbar {
    width: 6px;
}

::-webkit-scrollbar-track {
    background: var(--deep-bg);
}

::-webkit-scrollbar-thumb {
    background: var(--evergreen);
    border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--fern-dark);
}