:root {
    --bg: #050816;
    --bg-deep: #030712;
    --panel: rgba(15, 23, 42, 0.92);
    --panel-2: rgba(17, 24, 39, 0.96);
    --blue: #1d4ed8;
    --blue-light: #60a5fa;
    --cyan: #7dd3fc;
    --text: #e5e7eb;
    --text-main: #f8fafc;
    --muted: #94a3b8;
    --line: rgba(148, 163, 184, 0.24);
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    background:
        radial-gradient(circle at 12% 10%, rgba(29, 78, 216, 0.28), transparent 26%),
        radial-gradient(circle at 90% 0%, rgba(96, 165, 250, 0.12), transparent 30%),
        linear-gradient(180deg, #050816 0%, #07111f 46%, #030712 100%);
    color: var(--text);
    font-family:
        system-ui,
        -apple-system,
        BlinkMacSystemFont,
        "Segoe UI",
        sans-serif;
    line-height: 1.9;
}

body::before {
    content: "";
    position: fixed;
    inset: 0;
    z-index: -1;
    opacity: 0.08;
    background-image:
        linear-gradient(rgba(125, 211, 252, 0.32) 1px, transparent 1px),
        linear-gradient(90deg, rgba(125, 211, 252, 0.32) 1px, transparent 1px);
    background-size: 48px 48px;
}

/* Header */

.entry-header {
    position: fixed;
    z-index: 100;
    top: 0;
    left: 0;
    display: flex;
    width: 100%;
    min-height: 64px;
    align-items: center;
    justify-content: space-between;
    padding: 0 32px;
    border-bottom: 1px solid rgba(148, 163, 184, 0.18);
    background: rgba(3, 7, 18, 0.84);
    backdrop-filter: blur(14px);
}

.entry-logo {
    color: var(--text-main);
    text-decoration: none;
    font-size: 15px;
    font-weight: 900;
    letter-spacing: 0.18em;
}

.entry-nav {
    display: flex;
    gap: 24px;
}

.entry-nav a {
    color: rgba(226, 232, 240, 0.68);
    text-decoration: none;
    font-size: 13px;
    font-weight: 700;
}

.entry-nav a:hover,
.entry-nav a.active {
    color: var(--cyan);
}

/* Hero */

.hero-section {
    position: relative;
    min-height: 100vh;
    padding: 112px 24px 72px;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    pointer-events: none;
}

.hero-bg::before {
    content: "CIPHER";
    position: absolute;
    top: 12%;
    left: -3%;
    color: rgba(255, 255, 255, 0.035);
    font-size: clamp(90px, 18vw, 250px);
    font-weight: 900;
    letter-spacing: 0.04em;
    line-height: 1;
}

.hero-bg::after {
    content: "";
    position: absolute;
    right: -12%;
    bottom: 8%;
    width: 48vw;
    height: 48vw;
    border: 1px solid rgba(96, 165, 250, 0.22);
    transform: rotate(45deg);
}

.hero-inner {
    position: relative;
    z-index: 2;
    display: grid;
    max-width: 1160px;
    min-height: calc(100vh - 184px);
    grid-template-columns: minmax(0, 1.05fr) minmax(320px, 0.95fr);
    gap: 44px;
    align-items: center;
    margin: 0 auto;
}

.hero-copy {
    position: relative;
}

.hero-copy::before {
    content: "";
    position: absolute;
    top: -34px;
    left: -28px;
    width: 180px;
    height: 180px;
    border-top: 4px solid var(--blue-light);
    border-left: 4px solid var(--blue-light);
    opacity: 0.64;
}

.hero-label {
    margin: 0 0 10px;
    color: var(--cyan);
    font-size: 13px;
    font-weight: 800;
    letter-spacing: 0.16em;
}

.hero-date {
    margin: 0 0 24px;
    color: var(--muted);
    font-size: 14px;
    font-weight: 700;
}

.hero-copy h1 {
    margin: 0;
    color: var(--text-main);
    font-size: clamp(36px, 5.4vw, 68px);
    line-height: 1.18;
    letter-spacing: 0.02em;
}

.hero-subcopy {
    margin: 30px 0 0;
    color: #cbd5e1;
    font-size: 18px;
    line-height: 2;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 16px;
    margin-top: 40px;
}

.main-button,
.sub-button {
    display: inline-flex;
    min-height: 52px;
    align-items: center;
    justify-content: center;
    padding: 0 24px;
    transform: skewX(-10deg);
    text-decoration: none;
    font-weight: 900;
    transition:
        transform 0.18s ease,
        box-shadow 0.18s ease,
        background 0.18s ease,
        border-color 0.18s ease;
}

.main-button span,
.sub-button span {
    transform: skewX(10deg);
}

.main-button {
    background: var(--blue);
    color: #ffffff;
    box-shadow: 12px 12px 0 rgba(96, 165, 250, 0.18);
}

.sub-button {
    border: 1px solid rgba(96, 165, 250, 0.46);
    background: rgba(15, 23, 42, 0.62);
    color: #dbeafe;
}

.main-button:hover,
.sub-button:hover {
    transform: skewX(-10deg) translateY(-3px);
}

.main-button:hover {
    box-shadow: 16px 16px 0 rgba(96, 165, 250, 0.22);
}

.hero-panel {
    position: relative;
}

.hero-panel::before {
    content: "";
    position: absolute;
    inset: 22px -18px -22px 18px;
    background: rgba(29, 78, 216, 0.22);
    transform: skewX(-6deg);
}

/* Hero image */

.hero-panel {
    position: relative;
    width: 100%;
    max-width: 540px;
    margin-left: auto;
}

.hero-panel::before {
    content: "";
    position: absolute;
    inset: 22px -18px -22px 18px;
    background: rgba(29, 78, 216, 0.22);
    transform: skewX(-6deg);
}

.hero-image-frame {
    position: relative;
    z-index: 2;
    width: 100%;
    aspect-ratio: 1 / 1;
    margin: 0;
    overflow: hidden;
    border: 1px solid rgba(96, 165, 250, 0.32);
    background: rgba(15, 23, 42, 0.92);
    box-shadow: 0 28px 90px rgba(0, 0, 0, 0.3);
}

.hero-image-frame::before {
    content: "";
    position: absolute;
    inset: 22px;
    z-index: 2;
    border: 1px solid rgba(148, 163, 184, 0.22);
    pointer-events: none;
}

.hero-image-frame::after {
    content: "";
    position: absolute;
    inset: 0;
    z-index: 3;
    background:
        linear-gradient(
            180deg,
            rgba(3, 7, 18, 0.04),
            rgba(3, 7, 18, 0.28)
        );
    pointer-events: none;
}

.hero-image {
    display: block;
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: center;
    filter:
        contrast(1.08)
        saturate(0.86)
        brightness(0.82);
}

.scroll-text {
    position: absolute;
    right: 34px;
    bottom: 30px;
    margin: 0;
    color: rgba(226, 232, 240, 0.5);
    font-size: 12px;
    font-weight: 900;
    letter-spacing: 0.2em;
    writing-mode: vertical-rl;
}

/* Sections */

.content-section {
    max-width: 1120px;
    margin: 0 auto;
    padding: 82px 24px;
}

.section-title-block {
    display: flex;
    gap: 24px;
    align-items: flex-start;
    margin-bottom: 30px;
}

.section-num {
    margin: 0;
    color: rgba(96, 165, 250, 0.28);
    font-size: clamp(58px, 8vw, 100px);
    font-weight: 900;
    line-height: 0.85;
}

.section-label {
    margin: 0 0 8px;
    color: var(--cyan);
    font-size: 14px;
    font-weight: 800;
}

.section-title-block h2 {
    margin: 0;
    color: var(--text-main);
    font-size: clamp(30px, 4vw, 48px);
    line-height: 1.28;
}

.text-box,
.guide-box,
.cipher-note {
    border: 1px solid var(--line);
    background: rgba(15, 23, 42, 0.9);
    box-shadow: 0 24px 80px rgba(0, 0, 0, 0.18);
}

.text-box {
    position: relative;
    padding: 38px;
}

.text-box::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 7px;
    height: 100%;
    background: var(--blue);
}

.text-box p {
    margin: 0 0 18px;
    color: #dbe4ef;
}

.text-box p:last-child {
    margin-bottom: 0;
}

.video{
    position: relative;
    width: 100%;
    aspect-ratio: 16 / 9;
    margin-top: 4rem;
    border: 2px solid rgb(21, 35, 77);
    background: rgba(15, 23, 42, 0.92);
}

/* Flow */

.flow-area {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
}

.flow-card {
    position: relative;
    display: block;
    min-height: 280px;
    padding: 30px;
    overflow: hidden;
    border: 1px solid var(--line);
    background: rgba(17, 24, 39, 0.94);
    color: inherit;
    text-align: left;
    cursor: pointer;
    transition:
        transform 0.18s ease,
        border-color 0.18s ease,
        background 0.18s ease,
        box-shadow 0.18s ease;
}

.flow-card::before {
    content: "";
    position: absolute;
    top: 0;
    right: -70px;
    width: 150px;
    height: 100%;
    background: rgba(29, 78, 216, 0.2);
    transform: skewX(-18deg);
}

.flow-card:hover,
.flow-card.active {
    border-color: rgba(96, 165, 250, 0.72);
    background: rgba(23, 37, 84, 0.88);
    box-shadow: 0 24px 64px rgba(0, 0, 0, 0.24);
    transform: translateY(-5px);
}

.card-num {
    position: relative;
    z-index: 2;
    display: inline-block;
    margin-bottom: 20px;
    color: var(--cyan);
    font-size: 38px;
    font-weight: 900;
    line-height: 1;
}

.flow-card h3 {
    position: relative;
    z-index: 2;
    margin: 0 0 12px;
    color: var(--text-main);
    font-size: 22px;
    line-height: 1.4;
}

.flow-card p {
    position: relative;
    z-index: 2;
    margin: 0;
    color: #cbd5e1;
    font-size: 14px;
}

/* Cipher note */

.cipher-note {
    margin-top: 22px;
    padding: 28px 34px;
    border-left: 6px solid var(--blue-light);
    background:
        linear-gradient(90deg, rgba(29, 78, 216, 0.22), rgba(15, 23, 42, 0.94));
}

.note-heading {
    margin: 0 0 12px;
    color: var(--cyan);
    font-weight: 800;
}

#cipherText {
    min-height: 66px;
    margin: 0;
    color: #dbeafe;
    white-space: pre-line;
    transition: opacity 0.16s ease;
}

#cipherText.is-changing {
    opacity: 0.25;
}

/* Guide */

.guide-box {
    padding: 36px 40px;
}

.guide-box ul {
    margin: 0;
    padding-left: 1.2em;
}

.guide-box li {
    margin-bottom: 12px;
    color: #dbe4ef;
}

code {
    padding: 2px 6px;
    border: 1px solid rgba(148, 163, 184, 0.3);
    background: rgba(2, 6, 23, 0.58);
    color: #bfdbfe;
    font-family: Consolas, monospace;
}

/* Start */

.start-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 20px;
}

.start-card {
    position: relative;
    display: block;
    min-height: 220px;
    padding: 34px;
    overflow: hidden;
    border: 1px solid var(--line);
    background: rgba(17, 24, 39, 0.94);
    color: inherit;
    text-decoration: none;
    transition:
        transform 0.18s ease,
        border-color 0.18s ease,
        background 0.18s ease,
        box-shadow 0.18s ease;
}

.start-card::before {
    content: "";
    position: absolute;
    right: -80px;
    bottom: 0;
    width: 190px;
    height: 100%;
    background: rgba(29, 78, 216, 0.22);
    transform: skewX(-18deg);
}

.start-card:hover {
    border-color: rgba(96, 165, 250, 0.72);
    background: rgba(23, 37, 84, 0.88);
    box-shadow: 0 24px 64px rgba(0, 0, 0, 0.24);
    transform: translateY(-5px);
}

.start-card span,
.start-card strong,
.start-card small {
    position: relative;
    z-index: 2;
}

.start-card span {
    display: block;
    color: var(--cyan);
    font-size: 14px;
    font-weight: 800;
}

.start-card strong {
    display: block;
    margin-top: 12px;
    color: var(--text-main);
    font-size: 28px;
    line-height: 1.35;
}

.start-card small {
    display: block;
    margin-top: 12px;
    color: #cbd5e1;
    font-size: 14px;
}

/* Animation */

.reveal {
    opacity: 0;
    transform: translateY(24px);
    transition:
        opacity 0.55s ease,
        transform 0.55s ease;
}

.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Footer */

.entry-footer {
    max-width: 1120px;
    margin: auto;
    padding: 32px 24px 48px;
    color: rgba(226, 232, 240, 0.58);
    font-size: 13px;
    text-align: center;
}

.entry-footer p {
    margin: 0;
    padding-top: 20px;
    border-top: 1px solid rgba(148, 163, 184, 0.18);
}

/* Responsive */

@media (max-width: 900px) {
    .entry-header {
        padding: 0 18px;
    }

    .entry-nav {
        display: none;
    }

    .hero-inner,
    .flow-area,
    .start-grid {
        grid-template-columns: 1fr;
    }

    .hero-panel {
        max-width: 420px;
        margin: 0 auto;
    }

    .hero-section {
        padding-top: 92px;
    }

    .hero-inner {
        min-height: auto;
    }

    .hero-copy::before {
        left: -14px;
    }

    .image-placeholder {
        min-height: 340px;
    }

    .content-section {
        padding: 62px 18px;
    }

    .section-title-block {
        gap: 16px;
    }
}

@media (max-width: 560px) {
    .hero-section {
        padding-inline: 16px;
    }

    .hero-actions {
        flex-direction: column;
    }

    .main-button,
    .sub-button {
        width: 100%;
    }

    .hero-panel {
        max-width: 100%;
    }

    .text-box,
    .guide-box,
    .cipher-note,
    .flow-card,
    .start-card {
        padding: 26px;
    }

    .section-title-block {
        display: block;
    }

    .section-num {
        margin-bottom: 10px;
    }
    
    .scroll-text{
        display: none;
    }
}

/* =========================================================
   Flow card 02 — static display
========================================================= */

.flow-card-static {
    cursor: default;
    transition: none;
}

.flow-card-static:hover,
.flow-card-static:focus,
.flow-card-static:focus-visible {
    border-color: var(--line);
    background: rgba(17, 24, 39, 0.94);
    box-shadow: none;
    transform: none;
    outline: none;
}