Found the following HTML validation problems:
background.html:50:82: Warning: inserting implicit <p>


background.html:57:1: Warning: missing </button> before <p>


background.html:59:4: Warning: inserting implicit <button>


background.html:67:24: Warning: inserting implicit <p>


background.html:76:1: Warning: missing </button> before <p>


background.html:78:4: Warning: inserting implicit <button>


background.html:86:24: Warning: inserting implicit <p>


background.html:133:1: Warning: inserting implicit <p>


background.html:143:1: Warning: inserting implicit <p>


background.html:178:1: Warning: inserting implicit <p>


background.html:197:1: Warning: inserting implicit <p>


background.html:216:1: Warning: inserting implicit <p>


background.html:235:1: Warning: inserting implicit <p>


background.html:254:1: Warning: inserting implicit <p>


background.html:273:1: Warning: inserting implicit <p>


background.html:292:1: Warning: inserting implicit <p>


background.html:311:1: Warning: inserting implicit <p>


background.html:330:1: Warning: inserting implicit <p>


background.html:349:1: Warning: inserting implicit <p>


background.html:368:1: Warning: inserting implicit <p>


background.html:59:4: Warning: Implicit <button> anchor "id" duplicated by Tidy.


background.html:76:1: Warning: <button> anchor "id" already defined


background.html:78:4: Warning: Implicit <button> anchor "id" duplicated by Tidy.


border.html:81:1: Warning: inserting implicit <p>


border.html:88:1: Warning: inserting implicit <p>


border.html:95:1: Warning: inserting implicit <p>


border.html:102:1: Warning: inserting implicit <p>


border.html:109:1: Warning: inserting implicit <p>


border.html:116:1: Warning: inserting implicit <p>


border.html:123:1: Warning: inserting implicit <p>


border.html:130:1: Warning: inserting implicit <p>


border.html:137:1: Warning: inserting implicit <p>


border.html:147:1: Warning: inserting implicit <p>


border.html:167:1: Warning: inserting implicit <p>


border.html:174:1: Warning: inserting implicit <p>


border.html:181:1: Warning: inserting implicit <p>


border.html:188:1: Warning: inserting implicit <p>


border.html:195:1: Warning: inserting implicit <p>


border.html:202:1: Warning: inserting implicit <p>


border.html:212:1: Warning: inserting implicit <p>


display.html:79:1: Warning: inserting implicit <p>


display.html:89:16: Warning: inserting implicit <p>


display.html:119:1: Warning: inserting implicit <p>


display.html:129:1: Warning: inserting implicit <p>


flex.html:93:23: Warning: inserting implicit <p>


flex.html:119:1: Warning: missing </label> before <p>


flex.html:119:42: Warning: inserting implicit <label>


flex.html:136:1: Warning: inserting implicit <p>


flex.html:137:58: Warning: missing </span> before <p>


flex.html:137:1: Warning: missing </label> before <p>


flex.html:137:67: Warning: inserting implicit <label>


flex.html:137:67: Warning: inserting implicit <span>


flex.html:150:1: Warning: inserting implicit <p>


flex.html:160:1: Warning: inserting implicit <p>


flex.html:168:83: Warning: inserting implicit <p>


flex.html:184:29: Warning: inserting implicit <p>


flex.html:210:1: Warning: inserting implicit <p>


flex.html:217:1: Warning: inserting implicit <p>


flex.html:227:1: Warning: inserting implicit <p>


flex.html:230:91: Warning: inserting implicit <p>


flex.html:254:1: Warning: inserting implicit <p>


flex.html:261:1: Warning: inserting implicit <p>


flex.html:271:1: Warning: inserting implicit <p>


flex.html:279:52: Warning: inserting implicit <p>


flex.html:304:1: Warning: inserting implicit <p>


flex.html:311:1: Warning: inserting implicit <p>


flex.html:318:1: Warning: inserting implicit <p>


flex.html:328:1: Warning: inserting implicit <p>


flex.html:329:70: Warning: inserting implicit <p>


flex.html:354:1: Warning: inserting implicit <p>


flex.html:361:1: Warning: inserting implicit <p>


flex.html:368:1: Warning: inserting implicit <p>


flex.html:378:1: Warning: inserting implicit <p>


flex.html:379:85: Warning: inserting implicit <p>


flex.html:404:1: Warning: inserting implicit <p>


flex.html:411:1: Warning: inserting implicit <p>


flex.html:418:1: Warning: inserting implicit <p>


flex.html:428:1: Warning: inserting implicit <p>


flex.html:429:72: Warning: inserting implicit <p>


flex.html:454:1: Warning: inserting implicit <p>


flex.html:461:1: Warning: inserting implicit <p>


flex.html:468:1: Warning: inserting implicit <p>


flex.html:478:1: Warning: inserting implicit <p>


flex.html:479:64: Warning: inserting implicit <p>


flex.html:504:1: Warning: inserting implicit <p>


flex.html:511:1: Warning: inserting implicit <p>


flex.html:518:1: Warning: inserting implicit <p>


flex.html:528:1: Warning: inserting implicit <p>


flex.html:537:83: Warning: inserting implicit <p>


flex.html:562:1: Warning: inserting implicit <p>


flex.html:569:1: Warning: inserting implicit <p>


flex.html:576:1: Warning: inserting implicit <p>


flex.html:586:1: Warning: inserting implicit <p>


font.html:93:16: Warning: inserting implicit <p>


font.html:111:1: Warning: inserting implicit <p>


margin.html:88:75: Warning: inserting implicit <p>


margin.html:108:1: Warning: inserting implicit <p>


padding.html:63:31: Warning: inserting implicit <p>


padding.html:83:1: Warning: missing </label> before <p>


padding.html:83:42: Warning: inserting implicit <label>


padding.html:100:1: Warning: inserting implicit <p>


padding.html:101:58: Warning: missing </span> before <p>


padding.html:101:1: Warning: missing </label> before <p>


padding.html:101:67: Warning: inserting implicit <label>


padding.html:101:67: Warning: inserting implicit <span>


padding.html:117:1: Warning: inserting implicit <p>


padding.html:118:39: Warning: inserting implicit <p>


padding.html:140:1: Warning: missing </label> before <p>


padding.html:140:42: Warning: inserting implicit <label>


padding.html:157:1: Warning: inserting implicit <p>


padding.html:158:58: Warning: missing </span> before <p>


padding.html:158:1: Warning: missing </label> before <p>


padding.html:158:67: Warning: inserting implicit <label>


padding.html:158:67: Warning: inserting implicit <span>


padding.html:174:1: Warning: inserting implicit <p>


padding.html:175:30: Warning: inserting implicit <p>


padding.html:198:1: Warning: missing </label> before <p>


padding.html:198:42: Warning: inserting implicit <label>


padding.html:215:1: Warning: inserting implicit <p>


padding.html:216:58: Warning: missing </span> before <p>


padding.html:216:1: Warning: missing </label> before <p>


padding.html:216:67: Warning: inserting implicit <label>


padding.html:216:67: Warning: inserting implicit <span>


padding.html:232:1: Warning: inserting implicit <p>


padding.html:138:1: Warning: <div> anchor "id" already defined


padding.html:196:1: Warning: <div> anchor "id" already defined


shadow.html:66:1: Warning: inserting implicit <p>


shadow.html:73:1: Warning: inserting implicit <p>


shadow.html:80:1: Warning: inserting implicit <p>


shadow.html:87:1: Warning: inserting implicit <p>


shadow.html:94:1: Warning: inserting implicit <p>


shadow.html:101:1: Warning: inserting implicit <p>


shadow.html:111:1: Warning: inserting implicit <p>


style-pronoun.html:25:61: Warning: inserting implicit <p>


style-pronoun.html:30:92: Warning: inserting implicit <p>


text.html:123:1: Warning: inserting implicit <p>