/* ============================================================
   宋韻 · 独立页外壳 SONGYUN PAGE SHELL
   给 snake / tetris / gobang / fruit-ninja / 作业页 等自带内联样式的
   单文件页面，统一换上宣纸 · 汝窑天青 · 朱砂印的外观。
   用法：在各页 </style> 之后 <link> 本文件，靠层叠顺序覆盖。
   ============================================================ */

:root {
    --sy-paper: #F4F0E6;
    --sy-paper-raised: #FBF8F1;
    --sy-paper-sunk: #EFEADD;
    --sy-ink: #1F1D19;
    --sy-ink-2: #555046;
    --sy-ink-3: #8B8474;
    --sy-celadon: #5F877D;
    --sy-celadon-deep: #40645B;
    --sy-cinnabar: #A6392E;
    --sy-ochre: #A9853F;
    --sy-hairline: rgba(31, 29, 25, 0.13);
    --sy-hairline-strong: rgba(31, 29, 25, 0.26);
    --sy-serif: "Songti SC", "STSong", "Noto Serif CJK SC", "Source Han Serif SC",
                "SimSun", "宋体", Georgia, serif;
    --sy-kai: "Kaiti SC", "STKaiti", "KaiTi", "楷体", var(--sy-serif);
    --sy-sans: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB",
               "Microsoft YaHei", sans-serif;
    --sy-latin: "Optima", "Palatino Linotype", Palatino, Georgia, serif;
    --sy-ease: cubic-bezier(0.16, 0.84, 0.28, 1);
    --sy-grain: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='260' height='260'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.82' numOctaves='4' stitchTiles='stitch'/%3E%3CfeColorMatrix type='saturate' values='0'/%3E%3C/filter%3E%3Crect width='260' height='260' filter='url(%23n)'/%3E%3C/svg%3E");
}

/* ==================== 夜宣（暗底页面用） ==================== */
[data-songyun="night"] {
    --sy-paper: #121310;
    --sy-paper-raised: #1B1C16;
    --sy-paper-sunk: #191A15;
    --sy-ink: #ECE6D6;
    --sy-ink-2: #ADA593;
    --sy-ink-3: #78715F;
    --sy-celadon: #8CB3A7;
    --sy-celadon-deep: #A8C9BE;
    --sy-cinnabar: #CB5A48;
    --sy-ochre: #C6A162;
    --sy-hairline: rgba(236, 230, 214, 0.13);
    --sy-hairline-strong: rgba(236, 230, 214, 0.26);
}

/* 这些页面各自用通用变量名声明主题（metronome / furigana 等），
   本表在其后加载，同特异度后来居上，直接把调色盘换成宋韵夜色 */
[data-songyun="night"] {
    --bg-primary: #121310;
    --bg-secondary: #191A15;
    --bg-tertiary: #22231C;
    --bg-card: #1B1C16;
    --bg-elevated: #202118;

    --accent-primary: #8CB3A7;
    --accent-secondary: #A8C9BE;
    --accent-warm: #CB5A48;
    --accent-warm-hover: #DE7461;
    --accent: #8CB3A7;
    --primary: #8CB3A7;

    --text-primary: #ECE6D6;
    --text-secondary: #ADA593;
    --text-muted: #78715F;
    --text-tertiary: #78715F;

    --border: rgba(236, 230, 214, 0.13);
    --border-color: rgba(236, 230, 214, 0.13);

    --beat-1: #CB5A48;
    --beat-2: #C6A162;
    --beat-3: #8CB3A7;
    --beat-4: #7B9BB6;
}

[data-songyun="night"] body::before {
    mix-blend-mode: screen;
    opacity: 0.075;
}

[data-songyun="night"] body {
    background-image:
        radial-gradient(120% 90% at 50% -10%, rgba(140, 179, 167, 0.09), transparent 58%),
        radial-gradient(80% 60% at 100% 100%, rgba(198, 161, 98, 0.06), transparent 62%);
}

[data-songyun="night"] .btn-restart:hover,
[data-songyun="night"] .btn-primary:hover,
[data-songyun="night"] .control-btn.primary:hover,
[data-songyun="night"] .difficulty-btn.active,
[data-songyun="night"] .level-btn.active,
[data-songyun="night"] .mode-btn.active {
    color: var(--sy-paper);
}

/* ==================== 纸底 ==================== */
body {
    background: var(--sy-paper);
    background-image:
        radial-gradient(120% 90% at 50% -10%, rgba(95, 135, 125, 0.09), transparent 58%),
        radial-gradient(80% 60% at 100% 100%, rgba(169, 133, 63, 0.07), transparent 62%);
    background-attachment: fixed;
    color: var(--sy-ink);
    font-family: var(--sy-sans);
    letter-spacing: 0.012em;
}

body::before {
    content: '';
    position: fixed;
    inset: 0;
    z-index: 0;
    pointer-events: none;
    background-image: var(--sy-grain);
    opacity: 0.055;
    mix-blend-mode: multiply;
}

/* 装裱边 */
body::after {
    content: '';
    position: fixed;
    inset: 12px;
    z-index: 40;
    pointer-events: none;
    border: 1px solid var(--sy-hairline);
}

/* ==================== 标题 ==================== */
body > h1,
h1 {
    font-family: var(--sy-serif);
    font-weight: 600;
    letter-spacing: 0.16em;
    color: var(--sy-ink);
    text-shadow: none;
}

body > h1 {
    position: relative;
    z-index: 1;
    margin-bottom: 28px;
    font-size: clamp(1.7rem, 4.4vw, 2.5rem);
    text-align: center;
}

/* 标题下的朱砂细线 */
body > h1::after {
    content: '';
    display: block;
    width: 44px;
    height: 2px;
    margin: 18px auto 0;
    background: var(--sy-cinnabar);
}

h2, h3, h4 {
    font-family: var(--sy-serif);
    letter-spacing: 0.1em;
    color: var(--sy-ink);
}

/* ==================== 册页容器 ==================== */
.game-container,
.container,
.main-container,
.content-wrapper {
    position: relative;
    z-index: 1;
    background: var(--sy-paper-raised);
    border: 1px solid var(--sy-hairline);
    border-radius: 3px;
    box-shadow:
        0 2px 4px rgba(45, 38, 26, 0.05),
        0 22px 50px -32px rgba(45, 38, 26, 0.4);
}

/* 容器左上角的朱砂角线 */
.game-container::before {
    content: '';
    position: absolute;
    top: 10px;
    left: 10px;
    width: 18px;
    height: 18px;
    border-top: 1px solid var(--sy-cinnabar);
    border-left: 1px solid var(--sy-cinnabar);
    opacity: 0.5;
    pointer-events: none;
}

.game-header {
    padding-bottom: 16px;
    border-bottom: 1px solid var(--sy-hairline);
}

.game-info {
    font-family: var(--sy-serif);
    font-size: 1.02rem;
    font-weight: 600;
    letter-spacing: 0.1em;
    color: var(--sy-ink);
}

.game-instructions,
.instructions,
.tips {
    font-family: var(--sy-kai);
    letter-spacing: 0.14em;
    color: var(--sy-ink-3);
}

/* ==================== 按钮：细框 → 墨填 ==================== */
.btn,
button.btn,
.game-controls button,
.control-btn,
.btn-primary,
.btn-secondary {
    padding: 9px 20px;
    border: 1px solid var(--sy-hairline-strong);
    border-radius: 2px;
    background: transparent;
    color: var(--sy-ink-2);
    font-family: var(--sy-serif);
    font-size: 13px;
    font-weight: 500;
    letter-spacing: 0.18em;
    box-shadow: none;
    transition: color 0.4s var(--sy-ease), background-color 0.4s var(--sy-ease),
                border-color 0.4s var(--sy-ease), transform 0.4s var(--sy-ease);
}

.btn:hover,
.game-controls button:hover,
.control-btn:hover {
    transform: none;
    box-shadow: none;
}

.btn-restart,
.btn-primary,
.control-btn.primary {
    background: transparent;
    color: var(--sy-ink-2);
}

.btn-restart:hover,
.btn-primary:hover,
.control-btn.primary:hover {
    background: var(--sy-celadon-deep);
    border-color: var(--sy-celadon-deep);
    color: #FBF6EC;
    box-shadow: none;
    transform: none;
}

.btn-home,
.btn-secondary {
    background: transparent;
    color: var(--sy-ink-2);
}

.btn-home:hover,
.btn-secondary:hover {
    background: var(--sy-cinnabar);
    border-color: var(--sy-cinnabar);
    color: #FBF6EC;
    box-shadow: none;
    transform: none;
}

/* ==================== 画布 ==================== */
canvas {
    border-radius: 2px;
}

#snake-canvas,
#tetris-canvas,
#gobang-canvas,
#game-canvas {
    border: 1px solid var(--sy-hairline-strong);
    border-radius: 2px;
    box-shadow: inset 0 0 0 1px rgba(251, 246, 236, 0.06),
                0 14px 32px -22px rgba(45, 38, 26, 0.5);
}

/* ==================== 弹窗 ==================== */
.game-over-modal,
.modal,
.overlay {
    background: rgba(31, 29, 25, 0.42);
    backdrop-filter: blur(6px);
    -webkit-backdrop-filter: blur(6px);
}

.game-over-content,
.modal-content {
    position: relative;
    background: var(--sy-paper-raised);
    border: 1px solid var(--sy-hairline-strong);
    border-radius: 3px;
    box-shadow: 0 40px 90px -48px rgba(45, 38, 26, 0.6);
}

.game-over-content::before {
    content: '';
    position: absolute;
    left: 50%;
    top: 0;
    width: 44px;
    height: 2px;
    background: var(--sy-cinnabar);
    transform: translateX(-50%);
}

.game-over-content h2,
.modal-content h2 {
    font-family: var(--sy-serif);
    font-weight: 600;
    letter-spacing: 0.2em;
    color: var(--sy-ink);
}

/* ==================== 难度 / 选择 ==================== */
.difficulty-btn,
.level-btn,
.mode-btn {
    border: 1px solid var(--sy-hairline);
    border-radius: 2px;
    background: transparent;
    color: var(--sy-ink-2);
    font-family: var(--sy-serif);
    letter-spacing: 0.16em;
}

.difficulty-btn.active,
.level-btn.active,
.mode-btn.active {
    background: var(--sy-ink);
    border-color: var(--sy-ink);
    color: var(--sy-paper);
}

/* ==================== 表单 ==================== */
input[type="text"],
input[type="number"],
input[type="password"],
textarea,
select {
    border: 1px solid var(--sy-hairline);
    border-radius: 2px;
    background: var(--sy-paper);
    color: var(--sy-ink);
}

input:focus,
textarea:focus,
select:focus {
    outline: none;
    border-color: var(--sy-celadon);
}

/* ==================== 分数 / 数字 ==================== */
.score,
.score-value,
.high-score,
#score,
#level,
#lines {
    font-family: var(--sy-latin);
    color: var(--sy-ink);
}

/* ==================== 返回落款印 ==================== */
.songyun-seal {
    position: fixed;
    right: 24px;
    bottom: 24px;
    z-index: 41;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 38px;
    height: 38px;
    background: var(--sy-cinnabar);
    color: #FBF6EC;
    font-family: var(--sy-serif);
    font-size: 17px;
    font-weight: 700;
    line-height: 1;
    border-radius: 1px;
    box-shadow: inset 0 0 0 1px rgba(251, 246, 236, 0.3);
    transform: rotate(-2deg);
    opacity: 0.9;
    transition: transform 0.5s var(--sy-ease), opacity 0.4s var(--sy-ease);
}

.songyun-seal:hover {
    transform: rotate(2deg) scale(1.06);
    opacity: 1;
}

@media (max-width: 560px) {
    body::after { inset: 8px; }
    .songyun-seal { right: 16px; bottom: 16px; }
}

@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        transition-duration: 0.01ms !important;
    }
}