* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: "PingFang SC", "Microsoft YaHei", sans-serif;
    color: #2c2c2c;
    background: #faf7f2;
}

a {
    color: #d06c88;
}

.landing {
    min-height: 100vh;
    background-size: cover;
    background-position: center;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 24px;
}

.overlay {
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at center, rgba(0, 0, 0, 0.2), rgba(0, 0, 0, 0.58));
}

.envelope-scene {
    position: relative;
    z-index: 2;
    width: min(94vw, 620px);
    display: grid;
    justify-items: center;
    cursor: pointer;
    opacity: 0;
    transform: translate3d(0, 0, 0);
    backface-visibility: hidden;
    -webkit-backface-visibility: hidden;
}

.envelope-shell,
.letter-card {
    transform: translateZ(0);
    backface-visibility: hidden;
    -webkit-backface-visibility: hidden;
}

.envelope-scene:focus-visible {
    outline: 2px solid rgba(255, 255, 255, 0.8);
    outline-offset: 8px;
    border-radius: 20px;
}

body.intro-start .envelope-scene {
    animation: envelope-shuriken-in 2.8s cubic-bezier(.22, .72, .2, 1) forwards;
    will-change: transform, opacity;
}

body.intro-done .envelope-scene {
    opacity: 1;
    transform: translate3d(0, 0, 0);
}

@keyframes envelope-shuriken-in {
    0% {
        opacity: 0;
        transform: translate3d(250px, 220px, 0) scale(0.22) rotate(-10deg);
    }
    24% {
        opacity: 1;
        transform: translate3d(200px, 165px, 0) scale(0.34) rotate(-8deg);
    }
    52% {
        opacity: 1;
        transform: translate3d(110px, 85px, 0) scale(0.6) rotate(-5deg);
    }
    76% {
        opacity: 1;
        transform: translate3d(34px, 16px, 0) scale(0.84) rotate(-2deg);
    }
    90% {
        opacity: 1;
        transform: translate3d(8px, -6px, 0) scale(1.03) rotate(1.5deg);
    }
    100% {
        opacity: 1;
        transform: translate3d(0, 0, 0) scale(1) rotate(0deg);
    }
}

.envelope-glow {
    position: absolute;
    width: 76%;
    height: 70px;
    bottom: 5px;
    background: radial-gradient(circle, rgba(0, 0, 0, 0.35), rgba(0, 0, 0, 0));
    filter: blur(5px);
    pointer-events: none;
}

.envelope-shell {
    --front-height: 250px;
    --flap-height: 215px;
    position: relative;
    width: min(92vw, 560px);
    height: 420px;
    perspective: 1200px;
}

.envelope-base {
    position: absolute;
    left: 0;
    right: 0;
    bottom: 0;
    height: var(--front-height);
    z-index: 1;
    border-radius: 0;
    background: linear-gradient(145deg, rgba(255, 224, 205, 0.96), rgba(238, 171, 156, 0.95));
    box-shadow: 0 24px 56px rgba(0, 0, 0, 0.35);
    pointer-events: none;
    transition: transform .8s ease;
}

.envelope-pocket {
    position: absolute;
    left: 0;
    right: 0;
    bottom: 24px;
    height: 330px;
    display: flex;
    justify-content: center;
    overflow: hidden;
    z-index: 2;
}

.envelope-front {
    position: absolute;
    left: 0;
    right: 0;
    bottom: 0;
    height: var(--front-height);
    z-index: 4;
    border-radius: 0 0 24px 24px;
    background: transparent;
    pointer-events: none;
    transition: transform .8s ease, opacity .8s ease;
}

.envelope-front::before,
.envelope-front::after {
    content: "";
    position: absolute;
    top: 0;
    width: 52%;
    height: 100%;
    background: linear-gradient(150deg, rgba(255, 243, 235, 0.65), rgba(230, 151, 145, 0.7));
    box-shadow: 0 16px 28px rgba(0, 0, 0, 0.16);
}

.envelope-front::before {
    left: 0;
    clip-path: polygon(0 0, 100% 52%, 0 100%);
}

.envelope-front::after {
    right: 0;
    clip-path: polygon(100% 0, 0 52%, 100% 100%);
}

.envelope-flap {
    position: absolute;
    left: 0;
    right: 0;
    top: calc(100% - var(--front-height) - 2px);
    height: var(--flap-height);
    z-index: 5;
    transform-origin: top center;
    transform: rotateX(0deg);
    transition: transform 1.1s cubic-bezier(.2, .65, .22, 1);
    background: linear-gradient(155deg, rgba(255, 214, 190, 0.96), rgba(244, 166, 149, 0.96));
    clip-path: polygon(50% 74%, 0 0, 100% 0);
    filter: drop-shadow(0 10px 18px rgba(0, 0, 0, 0.22));
    pointer-events: none;
    backface-visibility: hidden;
    -webkit-backface-visibility: hidden;
    transform-style: preserve-3d;
}

.letter-card {
    position: absolute;
    left: 50%;
    bottom: -44px;
    width: calc(100% - 34px);
    max-width: 526px;
    transform: translate(-50%, 60%);
    background: linear-gradient(140deg, rgba(255, 253, 249, 0.98), rgba(255, 247, 238, 0.95));
    border-radius: 22px;
    border: 1px solid rgba(255, 255, 255, 0.55);
    padding: 44px 34px 24px;
    text-align: center;
    box-shadow: 0 24px 54px rgba(0, 0, 0, 0.32);
    transition: transform 1.7s cubic-bezier(.2, .7, .18, 1), box-shadow .25s ease;
    overflow: hidden;
    z-index: 3;
    opacity: 0;
    pointer-events: none;
}

.letter-card > * {
    opacity: 0;
    transform: translateY(8px);
    transition: opacity .35s ease, transform .35s ease;
}

.letter-card::before,
.letter-card::after {
    content: "";
    position: absolute;
    inset: 12px;
    border-radius: 16px;
    pointer-events: none;
}

.letter-card::before {
    border: 1px solid rgba(208, 108, 136, 0.34);
}

.letter-card::after {
    inset: -70px auto auto -70px;
    width: 160px;
    height: 160px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(247, 214, 173, 0.3), rgba(247, 214, 173, 0));
}

.envelope-scene:hover .letter-card {
    box-shadow: 0 28px 60px rgba(0, 0, 0, 0.36);
}

.scene-tip {
    position: absolute;
    left: 50%;
    bottom: 18px;
    transform: translateX(-50%);
    margin: 0;
    color: #fffaf6;
    letter-spacing: 1px;
    font-size: 13px;
    white-space: nowrap;
    text-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}

.envelope-scene.is-opening .envelope-flap {
    transform: rotateX(180deg) translateY(-12px);
    opacity: 0;
    z-index: 1;
    transition: transform 1s cubic-bezier(.2, .65, .22, 1), opacity .7s ease;
}

.envelope-scene.is-opening .letter-card {
    transform: translate(-50%, -46%);
    z-index: 6;
    opacity: 1;
    pointer-events: auto;
}

.envelope-scene.is-opening .envelope-pocket {
    z-index: 6;
    overflow: visible;
}

.envelope-scene.is-opening .envelope-front {
    transform: translateY(28px);
    opacity: 0.88;
}

.envelope-scene.is-opening .envelope-base {
    transform: translateY(28px);
}

.envelope-scene.is-opening .scene-tip {
    opacity: 0;
    transform: translateY(10px);
    transition: all .35s ease;
}

.envelope-scene.is-opened .scene-tip {
    opacity: 0;
}

.envelope-scene.is-opened .letter-card {
    transform: translate(-50%, -48%);
    z-index: 6;
    opacity: 1;
    pointer-events: auto;
}

.envelope-scene.is-opened .envelope-pocket {
    z-index: 6;
    overflow: visible;
}

.envelope-scene.is-opened .envelope-front {
    transform: translateY(36px);
    opacity: 0.78;
}

.envelope-scene.is-opened .envelope-flap {
    opacity: 0;
    z-index: 1;
}

.envelope-scene.is-opened .envelope-base {
    transform: translateY(36px);
}

.envelope-scene.is-opened .letter-card > * {
    opacity: 1;
    transform: translateY(0);
}

.letter-card h1 {
    margin: 0 0 10px;
    font-size: 38px;
    line-height: 1.2;
    color: #8d3c56;
}

.stamp {
    display: inline-block;
    margin-bottom: 14px;
    padding: 4px 14px;
    border-radius: 999px;
    letter-spacing: .8px;
    font-size: 12px;
    color: #8d3c56;
    border: 1px solid rgba(141, 60, 86, 0.35);
    background: rgba(255, 255, 255, 0.8);
}

.dear-text {
    margin: 0 0 10px;
    color: #9e6b61;
    font-size: 14px;
    letter-spacing: .5px;
}

.invite-subtitle {
    margin: 0;
    font-size: 17px;
    color: #7d525f;
}

.invite-date {
    margin: 8px 0 0;
    color: #aa7a4f;
    font-size: 15px;
}

.opening-inline {
    margin: 12px 0 0;
    padding: 0 6px;
    color: #7b525f;
    line-height: 1.75;
    font-size: 14px;
    opacity: 0;
    transform: translateY(8px);
    transition: opacity .45s ease, transform .45s ease;
}

.open-btn {
    display: inline-block;
    margin-top: 18px;
    background: linear-gradient(135deg, #ce5f80, #e48a67);
    color: #fff;
    padding: 11px 26px;
    border-radius: 999px;
    font-weight: 600;
    box-shadow: 0 8px 18px rgba(206, 95, 128, 0.35);
    border: none;
    cursor: pointer;
    transition: transform .2s ease, box-shadow .2s ease, background .2s ease;
}

.open-btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 12px 22px rgba(206, 95, 128, 0.4);
}

.envelope-scene.is-opened .opening-inline {
    opacity: 1;
    transform: translateY(0);
}

.envelope-scene.is-opened .open-btn {
    background: linear-gradient(135deg, #8b5cf6, #6366f1);
}

.hint-text {
    display: block;
    margin-top: 10px;
    font-size: 12px;
    color: #936875;
    letter-spacing: .4px;
}

.opening-modal {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 99;
    padding: 16px;
}

.opening-modal.hidden {
    display: none;
}

.opening-content {
    width: min(92vw, 640px);
    background: #fff;
    border-radius: 14px;
    padding: 28px;
    text-align: center;
    line-height: 1.8;
}

.hero {
    min-height: 44vh;
    background: linear-gradient(120deg, #f8dbe3, #f0ebe8);
    background-size: cover;
    background-position: center;
}

.hero-mask {
    min-height: 44vh;
    background: rgba(0, 0, 0, 0.35);
    color: #fff;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 10px;
    padding: 26px;
    text-align: center;
}

.device-badge {
    margin: 0;
    padding: 4px 10px;
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.2);
    font-size: 12px;
}

.container {
    width: min(1100px, 92vw);
    margin: -50px auto 40px;
    display: grid;
    gap: 20px;
}

.card {
    background: #fff;
    border-radius: 14px;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
    padding: 20px;
}

.card h2 {
    margin-top: 0;
    color: #cb5f7e;
}

.gallery-grid,
.video-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 12px;
}

.gallery-grid figure,
.video-grid figure {
    margin: 0;
}

.gallery-grid img,
.video-grid video {
    width: 100%;
    border-radius: 10px;
    display: block;
    background: #f5f5f5;
}

.gallery-grid figcaption,
.video-grid figcaption {
    margin-top: 6px;
    font-size: 13px;
    color: #666;
}

.empty-text {
    color: #888;
}

.rsvp-form {
    display: grid;
    gap: 12px;
}

.rsvp-form label {
    display: grid;
    gap: 6px;
    font-size: 14px;
}

.rsvp-form input,
.rsvp-form textarea,
.rsvp-form select,
.rsvp-form button {
    border: 1px solid #ddd;
    border-radius: 8px;
    padding: 10px 12px;
    font-size: 15px;
}

.rsvp-form button {
    border: none;
    background: #d06c88;
    color: #fff;
    cursor: pointer;
}

.result-page {
    min-height: 100vh;
    display: grid;
    place-items: center;
}

.result-card {
    background: #fff;
    padding: 28px;
    border-radius: 14px;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
    text-align: center;
}

@media (max-width: 980px) {
    .gallery-grid,
    .video-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

@media (max-width: 640px) {
    .letter-card h1 {
        font-size: 30px;
    }

    .envelope-shell {
        --front-height: 232px;
        --flap-height: 198px;
        height: 390px;
    }

    .envelope-pocket {
        height: 302px;
    }

    .letter-card {
        width: calc(100% - 20px);
        padding: 34px 22px 22px;
    }

    .invite-subtitle {
        font-size: 15px;
    }

    .container {
        width: 94vw;
    }

    .gallery-grid,
    .video-grid {
        grid-template-columns: 1fr;
    }
}

@media (prefers-reduced-motion: reduce) {
    .envelope-scene {
        opacity: 1;
    }

    body.intro-start .envelope-scene {
        animation: none;
    }
}