/* kkaji.com - Flat Design Korean Language Journey */
/* Colors from DESIGN.md */
/* Earth ground: #e8dcc8 | Clean white: #fefcf8 */
/* Flat block 1: #5b8c5a (sage) | Flat block 2: #c4853f (sienna) */
/* Flat block 3: #4a7c9b (slate blue) | Flat block 4: #9b6b4a (umber) */
/* Text on color: #fefcf8 | Text on light: #2d2518 */
/* Watercolor: #8fbc8f, #daa520, #cd853f */

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Noto Sans KR', sans-serif;
    font-weight: 400;
    font-size: clamp(15px, 1.5vw, 18px);
    line-height: 1.75;
    color: #2d2518;
    background-color: #fefcf8;
    overflow-x: hidden;
}

/* ========================================
   SPLIT-SCREEN LAYOUT
   ======================================== */

.split-screen {
    display: flex;
    min-height: 100vh;
    width: 100%;
}

.split-left {
    width: 50%;
    background-color: #e8dcc8;
    padding: clamp(24px, 5vw, 64px);
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.split-right {
    width: 50%;
    background-color: #fefcf8;
    padding: clamp(24px, 5vw, 64px);
    display: flex;
    flex-direction: column;
    justify-content: center;
    position: relative;
}

/* ========================================
   SECTION 1: HERO
   ======================================== */

#hero {
    height: 100vh;
    min-height: 100vh;
    max-height: 100vh;
}

.hero-left {
    display: flex;
    align-items: center;
    justify-content: center;
}

.hero-hangul {
    font-family: 'Commissioner', sans-serif;
    font-weight: 800;
    font-size: clamp(80px, 18vw, 280px);
    color: #2d2518;
    line-height: 1;
    opacity: 0;
    transition: opacity 200ms ease;
}

.hero-hangul.visible {
    opacity: 1;
}

.hero-right {
    position: relative;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
}

.hero-right-content {
    position: relative;
    z-index: 2;
    text-align: center;
}

.hero-romanized {
    font-family: 'Commissioner', sans-serif;
    font-weight: 600;
    font-size: clamp(36px, 6vw, 80px);
    color: #2d2518;
    margin-bottom: 16px;
    letter-spacing: -0.02em;
}

.hero-tagline {
    font-family: 'Karla', sans-serif;
    font-weight: 400;
    font-size: clamp(16px, 2vw, 22px);
    color: #2d2518;
    opacity: 0;
    transition: opacity 400ms ease;
    letter-spacing: 0.02em;
}

.hero-tagline.visible {
    opacity: 1;
}

/* Watercolor splash in hero */
.watercolor-splash {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 1;
    pointer-events: none;
}

.watercolor-layer {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    transition: opacity 300ms ease;
}

.watercolor-layer.visible {
    opacity: 1;
}

.watercolor-layer-1 {
    background:
        radial-gradient(ellipse 80% 70% at 30% 40%, rgba(143, 188, 143, 0.25) 0%, transparent 70%),
        radial-gradient(ellipse 60% 50% at 70% 60%, rgba(218, 165, 32, 0.2) 0%, transparent 65%);
}

.watercolor-layer-2 {
    background:
        radial-gradient(ellipse 50% 60% at 50% 50%, rgba(205, 133, 63, 0.3) 0%, transparent 60%),
        radial-gradient(ellipse 40% 40% at 25% 70%, rgba(143, 188, 143, 0.2) 0%, transparent 55%);
}

.watercolor-layer-3 {
    background:
        radial-gradient(ellipse 35% 35% at 60% 35%, rgba(218, 165, 32, 0.35) 0%, transparent 50%),
        radial-gradient(ellipse 25% 30% at 40% 65%, rgba(205, 133, 63, 0.25) 0%, transparent 45%),
        radial-gradient(ellipse 20% 20% at 70% 70%, rgba(143, 188, 143, 0.3) 0%, transparent 40%);
}

/* ========================================
   SECTION 2: GRAMMAR - 어디까지
   ======================================== */

#grammar {
    min-height: 100vh;
}

.grammar-left {
    justify-content: flex-start;
    padding-top: clamp(48px, 8vw, 96px);
}

.section-title {
    font-family: 'Commissioner', sans-serif;
    font-weight: 600;
    font-size: clamp(28px, 5vw, 72px);
    color: #2d2518;
    margin-bottom: 4px;
}

.section-subtitle {
    font-family: 'Karla', sans-serif;
    font-weight: 400;
    font-style: italic;
    font-size: 14px;
    color: #9b6b4a;
    letter-spacing: 0.02em;
    margin-bottom: clamp(24px, 4vw, 48px);
}

/* Grammar Cards - TRUE FLAT (zero shadow, zero radius, zero gradient) */
.grammar-cards {
    display: flex;
    flex-direction: column;
    gap: 0;
}

.grammar-card {
    padding: clamp(20px, 3vw, 40px);
    color: #fefcf8;
    cursor: pointer;
    position: relative;
    border: none;
    border-radius: 0;
    box-shadow: none;
}

.grammar-card.flat-block-1 { background-color: #5b8c5a; }
.grammar-card.flat-block-2 { background-color: #c4853f; }
.grammar-card.flat-block-3 { background-color: #4a7c9b; }
.grammar-card.flat-block-4 { background-color: #9b6b4a; }

/* Instant hover color swaps - NO transition */
.grammar-card.flat-block-1:hover { background-color: #4a7c9b; }
.grammar-card.flat-block-2:hover { background-color: #9b6b4a; }
.grammar-card.flat-block-3:hover { background-color: #5b8c5a; }
.grammar-card.flat-block-4:hover { background-color: #c4853f; }

.card-badge {
    position: absolute;
    top: clamp(8px, 1vw, 16px);
    right: clamp(8px, 1vw, 16px);
    font-family: 'Karla', sans-serif;
    font-weight: 400;
    font-size: 12px;
    color: rgba(254, 252, 248, 0.7);
    letter-spacing: 0.02em;
}

.card-pattern {
    font-family: 'Commissioner', sans-serif;
    font-weight: 500;
    font-size: clamp(20px, 3vw, 36px);
    line-height: 1.3;
    margin-bottom: 8px;
}

.card-translation {
    font-family: 'Karla', sans-serif;
    font-weight: 400;
    font-size: 14px;
    color: rgba(254, 252, 248, 0.8);
    letter-spacing: 0.02em;
}

/* Grammar Right - Watercolor Scenes */
.grammar-right {
    justify-content: flex-start;
    padding-top: clamp(48px, 8vw, 96px);
    gap: clamp(24px, 4vw, 48px);
}

.watercolor-scene {
    position: relative;
    height: 150px;
    width: 100%;
}

.watercolor-scene .wc-base,
.watercolor-scene .wc-mid,
.watercolor-scene .wc-detail {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    transition: opacity 300ms ease;
}

.watercolor-scene .wc-base.visible { opacity: 1; }
.watercolor-scene .wc-mid.visible { opacity: 1; }
.watercolor-scene .wc-detail.visible { opacity: 1; }

/* Scene 1 - Landscape (place grammar) */
#watercolorScene1 .wc-base {
    background:
        radial-gradient(ellipse 90% 60% at 50% 70%, rgba(143, 188, 143, 0.2) 0%, transparent 70%);
}
#watercolorScene1 .wc-mid {
    background:
        radial-gradient(ellipse 60% 40% at 30% 50%, rgba(91, 140, 90, 0.25) 0%, transparent 60%),
        radial-gradient(ellipse 50% 40% at 70% 60%, rgba(143, 188, 143, 0.2) 0%, transparent 55%);
}
#watercolorScene1 .wc-detail {
    background:
        radial-gradient(ellipse 20% 25% at 25% 45%, rgba(91, 140, 90, 0.35) 0%, transparent 45%),
        radial-gradient(ellipse 15% 20% at 75% 55%, rgba(143, 188, 143, 0.3) 0%, transparent 40%),
        radial-gradient(ellipse 30% 15% at 50% 80%, rgba(91, 140, 90, 0.2) 0%, transparent 50%);
}

/* Scene 2 - Clock face (time grammar) */
#watercolorScene2 .wc-base {
    background:
        radial-gradient(ellipse 70% 70% at 50% 50%, rgba(218, 165, 32, 0.2) 0%, transparent 70%);
}
#watercolorScene2 .wc-mid {
    background:
        radial-gradient(circle 35% at 50% 50%, rgba(196, 133, 63, 0.25) 0%, transparent 60%),
        radial-gradient(ellipse 50% 50% at 50% 50%, rgba(218, 165, 32, 0.15) 0%, transparent 50%);
}
#watercolorScene2 .wc-detail {
    background:
        radial-gradient(circle 10% at 50% 30%, rgba(196, 133, 63, 0.4) 0%, transparent 40%),
        radial-gradient(ellipse 5% 25% at 50% 50%, rgba(218, 165, 32, 0.35) 0%, transparent 45%),
        radial-gradient(ellipse 25% 5% at 50% 50%, rgba(196, 133, 63, 0.3) 0%, transparent 45%);
}

/* Scene 3 - Map outline (extent grammar) */
#watercolorScene3 .wc-base {
    background:
        radial-gradient(ellipse 80% 60% at 50% 50%, rgba(74, 124, 155, 0.15) 0%, transparent 70%);
}
#watercolorScene3 .wc-mid {
    background:
        radial-gradient(ellipse 50% 50% at 40% 40%, rgba(74, 124, 155, 0.25) 0%, transparent 55%),
        radial-gradient(ellipse 40% 35% at 65% 60%, rgba(143, 188, 143, 0.2) 0%, transparent 50%);
}
#watercolorScene3 .wc-detail {
    background:
        radial-gradient(ellipse 20% 30% at 35% 35%, rgba(74, 124, 155, 0.35) 0%, transparent 40%),
        radial-gradient(ellipse 15% 15% at 60% 55%, rgba(74, 124, 155, 0.3) 0%, transparent 35%),
        radial-gradient(ellipse 25% 10% at 50% 70%, rgba(143, 188, 143, 0.25) 0%, transparent 40%);
}

/* Scene 4 - Abstract quantity */
#watercolorScene4 .wc-base {
    background:
        radial-gradient(ellipse 80% 70% at 50% 50%, rgba(155, 107, 74, 0.2) 0%, transparent 70%);
}
#watercolorScene4 .wc-mid {
    background:
        radial-gradient(ellipse 40% 50% at 35% 45%, rgba(205, 133, 63, 0.25) 0%, transparent 55%),
        radial-gradient(ellipse 45% 40% at 65% 55%, rgba(155, 107, 74, 0.2) 0%, transparent 50%);
}
#watercolorScene4 .wc-detail {
    background:
        radial-gradient(circle 15% at 30% 40%, rgba(205, 133, 63, 0.35) 0%, transparent 40%),
        radial-gradient(circle 12% at 55% 50%, rgba(155, 107, 74, 0.3) 0%, transparent 35%),
        radial-gradient(circle 10% at 70% 60%, rgba(218, 165, 32, 0.3) 0%, transparent 35%);
}

/* ========================================
   SECTION 3: INTERACTION - 얼마까지
   ======================================== */

#interaction {
    min-height: 100vh;
}

.interaction-left {
    justify-content: center;
}

.interaction-desc {
    font-family: 'Noto Sans KR', sans-serif;
    font-weight: 400;
    color: #2d2518;
    margin-top: 16px;
    max-width: 360px;
}

.interaction-right {
    justify-content: center;
    align-items: center;
}

.interaction-panel {
    display: flex;
    flex-direction: column;
    gap: 0;
    width: 100%;
    max-width: 500px;
}

.interact-row {
    display: flex;
    gap: 0;
}

.flat-btn {
    flex: 1;
    padding: clamp(20px, 3vw, 36px) clamp(16px, 2vw, 24px);
    border: none;
    border-radius: 0;
    box-shadow: none;
    color: #fefcf8;
    cursor: pointer;
    text-align: left;
    font-family: inherit;
    outline: none;
    background: none;
}

.flat-btn.flat-block-1 { background-color: #5b8c5a; }
.flat-btn.flat-block-2 { background-color: #c4853f; }
.flat-btn.flat-block-3 { background-color: #4a7c9b; }
.flat-btn.flat-block-4 { background-color: #9b6b4a; }

.btn-text {
    display: block;
    font-family: 'Commissioner', sans-serif;
    font-weight: 500;
    font-size: clamp(16px, 2.5vw, 24px);
    line-height: 1.3;
    margin-bottom: 6px;
}

.btn-meaning {
    display: block;
    font-family: 'Karla', sans-serif;
    font-weight: 400;
    font-size: 13px;
    color: rgba(254, 252, 248, 0.75);
    letter-spacing: 0.02em;
}

/* ========================================
   SECTION 4: CLOSING - 끝까지
   ======================================== */

#closing {
    min-height: 100vh;
    width: 100%;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    background-color: #e8dcc8;
}

.closing-watercolor {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 1;
    pointer-events: none;
}

.closing-wash {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

.closing-wash-1 {
    background: radial-gradient(ellipse 100% 80% at 20% 30%, rgba(143, 188, 143, 0.25) 0%, transparent 60%);
}

.closing-wash-2 {
    background: radial-gradient(ellipse 80% 90% at 80% 70%, rgba(218, 165, 32, 0.2) 0%, transparent 55%);
}

.closing-wash-3 {
    background: radial-gradient(ellipse 60% 60% at 50% 50%, rgba(205, 133, 63, 0.2) 0%, transparent 50%);
}

.closing-wash-4 {
    background: radial-gradient(ellipse 50% 70% at 30% 70%, rgba(155, 107, 74, 0.15) 0%, transparent 50%);
}

.closing-wash-5 {
    background: radial-gradient(ellipse 70% 50% at 70% 30%, rgba(91, 140, 90, 0.15) 0%, transparent 45%);
}

.closing-content {
    position: relative;
    z-index: 2;
    text-align: center;
}

.closing-hangul {
    font-family: 'Commissioner', sans-serif;
    font-weight: 800;
    font-size: clamp(40px, 10vw, 120px);
    color: #2d2518;
    line-height: 1.1;
    margin-bottom: 16px;
}

.closing-translation {
    font-family: 'Karla', sans-serif;
    font-weight: 400;
    font-style: italic;
    font-size: clamp(16px, 2vw, 24px);
    color: #9b6b4a;
    letter-spacing: 0.02em;
}

/* ========================================
   RESPONSIVE
   ======================================== */

@media (max-width: 768px) {
    .split-screen {
        flex-direction: column;
    }

    .split-left,
    .split-right {
        width: 100%;
    }

    #hero {
        height: auto;
        max-height: none;
    }

    .hero-left {
        min-height: 50vh;
    }

    .hero-right {
        min-height: 50vh;
    }

    .grammar-right {
        padding-top: clamp(24px, 4vw, 48px);
    }

    .interact-row {
        flex-direction: column;
    }
}